practical architectures for survivable systems and networks (phase

227

Upload: truongthu

Post on 18-Jan-2017

220 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Practical Architectures for Survivable Systems and Networks (Phase

������������� �������������������������������� ���"!#�!�� $��� &% �'�"�)(*�+� ,�-/.0�1�324�5��6&�

798;:�<�=?>3@BADCFE4GIHKJ�<�LNM�>PO�ERQTSVU

W3XZYV["\"];^VX3XVX_`baNc3dfePgihkj3lfm ^nX3X3XZo�p&qNq�\ m ] g \�r mihsc \"rVtvu

rV\"wyx g ]?]zt e rT{nr h t|rV}�ts]�~ _ c3dfe ts]�x m�� x c3g \ c \ _ c3�Z� ] g _ h rVt g ]z["�i]

� ] m ] g#����� ]?[ � rV\"\aNc3�Zd [ m ] g o _ h ]?\ _ ]��)rn} c3g r mBcVg�eo�p&qNq�\ m ] g \�r mihsc \"rVtvu�p cPc3��� ���9^��fW

WVW3W�p�r�{3]z\"��� cPc w���{3]z\'["]� ]?\�t c � r g��ya ���V�fXf^3�T�WV�f�VW

� ]zts] d�l"c \"]n���z���f�VX����f�V���^VWf 3�¡ r�¢£�I�z��3�VX���3�V���9^n�V�3�

� � � r h tv� � ]z[ � rn\"\R¤ a o�� � � gihK� _ c3�lfm�mBd �¦¥3¥��I�I� � _ ��t � � gihK� _ c3� ¥n\"]?[ � rV\�\

� _ � \ c �&tk]?w j3� ]?\ m�c x�o§[ d"d�c3g9m rV\�w©¨ h � _ t|r hs� ] g � � l"h � g ] d�c3g�m�h ��}�rV�i]zwª[ d�c \«� c3gi� ��[ d"d�c3g�m ]?w} e©mBl ]­¬ � o � � g��;e p&]?�i]?r g _ l �)rn} c3g r mBcVg�e ~®��p¯� � u�["\"w"] gFaNc \ mig r _ m ¨&��° ¡ �V�z��f T� a �XVXf^VX � ��\ ec3d"h \ hsc \"�?u3±�\�w h \ j �?u _ c \ _ ts[�� hsc \"�?u c3g g ] _ c3�Z� ]z\"w�r mihsc \���]�¢ d"g ]z�i��]?w l ] g ] h \�r g ] mBl"c ��] c x mil ]#rn[ mBl"cVgrV\"w²w c \ cVm \"] _ ]?���Br g�h t e«g ]�³�] _ mDmil ]F{ h ]��&� c x mil ]�¬ � o � � gi�;e p¯]z�i]?r g _ l ��rV} cVg r mic3g�eV� � l ] ��c {f�] g \ � ]?\ m _ c \ m r _ m¯h �I��\ mil"c \ eµ´ r g \"]?�;~ ´ r g \"]z�i��¤¶r g t �·�Zh t � uR�z�9 VW3^¸���'^V ¸�9�VXV�3� �

¹ ��º � � � � l"h � g ] d£cVg�m�g ] d"g ]?�i]z\ m ��r«� c3� ]�� l r m�d ] g � c \"rVt5{ h ]�� c xI� cV� ] d�cVm ]?\ mBh rVtst e ]z»£] _ mBh {V]r d"d�gic r _ l ]?� mic �Nr g w�w"]�{3]?t c3d"h \ j u _ c \�± j [ gih \ j u§rV\"w c3d ] g r mih \ jDl"hkj3l t e �i[ g { h {nrV}"ts]¯� e � m ] � rV\"w­\"] m �� c3gi� ]z\f{ hkgic \ � ]z\ m � � q m h � r _?_ ]?��� h }�ts] c \§�¼t h \"] h \ mil"g ]z]½x c3gi� �?u mil ]½± g � m�m � c x c3g¾d"gih \ mih \ j u mBl ] mil"hsg wx c3g½¿ ]?}µ} gic �&� h \ jZh \y\ h _ ]?t e _ gic ���it h \ � ]zw lfmi� tK�

lfmimid �À¥V¥��I�I� � _ �it � � gihv� _ cV� ¥n\�]?[ � rV\"\R¥��i[ g { h {nrV} h t hkm�eV�Ád �lfmimBd �À¥3¥¸�I�I� � _ �it � � g�hv� _ c3� ¥n\"]z[ � rV\"\R¥n��[ g { h {Vrn} h t hkm�e3�·d w�xl'm�mBd �¦¥3¥��I�I� � _ ��t � � g�hv� _ c3� ¥n\"]z[ � rn\"\R¥n��[ g { h {nrV} h t hÂm�e3�·lfmB� t

aNc \�� mBg [ _ mih {V]Dx®]z]?w"}�r _ �µh �&rVtk�Nr e �&�5]?t _ c3� ] � � rV\ eÃmBl rV\ � � � � �¶�¯Ä

Å

Page 2: Practical Architectures for Survivable Systems and Networks (Phase

Page 3: Practical Architectures for Survivable Systems and Networks (Phase

� ���������

��}"� mig r _ m � � l"h � g ] d�c3g�m �i[ �­� r gih�� ]z� mBl ]­rV\�rVt e � h � c x h \§x c3gi� r mBhkc \«� e � m ] � ��[ g { h {Vrn} h t �hÂm�e3� q m _ c \�� h w�] g � l"c � ��[ g { h {Vrn} h t hkm�e�g ]?tsr m ]z� mBcycVmBl ] g¶g ]� P[ hsg ] � ]z\ m �D�i[ _ l rV�¶�i] _ [ gihÂm�e ug ]?t h rV} h t hÂm�e u£rV\"w d ] g x c3g�� rV\ _ ] � q m _ c \�� h w�] g ��r l"h ] g r g _ l"h _ rVt�t|r e ] gih \ jyc x g ]� '[ hkg ] � ]z\ m �?urn�¯�5]?tkt¾rV� h \ m ] g w"] d ]z\"w"]z\ _ h ]?�¶r �Zc \ j�mBl"c �i] g ]� '[ hsg ] � ]?\ m � � q m#h w"]z\ mBh ±"]?� h \�rVw"]� '[�r _ h ]?�h \ ]�¢ h � mBh \ j _ c3�­� ] g _ h rVt½� e � m ] � �­rV\"w mil ]�rV}"�i]z\ _ ] c x _ c3�Zd£c \�]?\ m � mBl r m�l�h \"w"] g�mBl ]r mim r h \ � ]?\ mFc x#��[ g { h {nrV} h t hÂm�e3� q m�g ] _ c3�Z� ]z\"w"��� d ] _ h ± _ r g _ l"hÂm ] _ m [ g rVt½� mBg [ _ m [ g ]?�­rV\"wcnmBl ] g r d"d"g�c r _ l ]z� mBl r m _ rV\ l ]?t d c {3] g _ c3� ] mBl"c �i] h \"rVw"]� '[�r _ h ]z�?u h \ _ ts["w h \ jªg ]?��]�r g _ lrn\"wªw"]�{3]?t c3d"� ]?\ m w hkg ] _ mBhkc \"�&x c3g�mil ];x®[ m [ g ] � q m rnts� c � mig ]?���i]z� mBl ] hk�­d�c3g9m rV\ _ ] c x�� e �9�m ] � c3d ] g r mBhsc \"�?u�]?w"[ _ r mihsc \1u�rV\"w²r��Nr g ]z\"]?���¶rV� d r g9m�c x�r }"rVt|rV\ _ ]?wªr d"d"g�c r _ lªmBc �Nr g wr mim r h \ h \ j �i[ g { h {nrV} h t hÂm�e3�

� l ]#±"]?tsw c x)]?\"w"]?r�{ c3g rVw�w g ]z�i�i]zw h \ mil"h � g ] d�c3g9mIh � h \ l ] g ]z\ m t e­c3d ]?\ ]z\"w"]?w �5� ]z� g ]z�i]�r g _ lyg ]���i[�t m � rV\"w�\"]��+� c x m �½r g ] _ c3�­d�c \"]z\ m � r g ]½r d"d ]�r gih \ j r m r g r d"h w d r _ ] � ¡ c3g)mBl"h � g ]?rV� c \1u mBl ] g ] d�c3g9m� mig ]z�i�i]z��x®["\"w�r � ]z\ m rVts�zu�rn\"w h � h \ m ]?\"w"]zw mBc }£];r j [ h w"] mic _ ] g�m r h \ d"gih \ _ hkd ts]z�#rV\�w©r g _ l�hkm ] _ m [ g rVtw hkg ] _ mBhkc \"��� l�c �i] � e � m ] � r mBh _ ["�i] _ rV\ ts]?rVw mic � e � m ] � � mBl r m r g ] � ]�rV\ h \ j x®["tkt e ��[ g { h {Vrn}"ts] � q�\mBl r m � d"hsg�hkm u mil ] g ] d£cVg�m�h � h \ m ]?\�w"]?w mic �i] g {3]�rn��r _ c3l ] g ]?\ m¶g ]z� c [ g _ ]�x gic3� � l"h _ l©� rV\ e x®[ g9mBl ] gg ]z� c [ g _ ]z� _ rV\µ}£] j tk]�rV\"]zwy} e x c tst c � h \ j;mBl ] _ hkm ]?w g ]�x®] g ]z\ _ ]z��rV\�w�¬�p���� �� l ] g ] d£cVg�m�h � g ]?t|r mBh {V]?t e#�Zc w�]?� m�h \ hkm � h \ m ]?\ m?� q m w c ]?��\ cVm�mig�e�mic � c tk{V]�rVtst mBl ] d"g�c }"ts] � � c x l"c �

mBc w"]?� hsj \1u hk�­d ts] � ]?\ m uVrVw �­h \ h � m ] g u � r h \ m r h \1unrV\"w�[��i] l"hkj3l t e ��[ g { h {Vrn}"ts]5� e � m ] � �5rn\"w�\"] m � c3g�� � �� l"c ��] d"gic }"ts] � � g ]� '[ hkg ]�x®[ m [ g ] g ]z�i]�r g _ l rV\"w j3g ]�r m ] g w h � _ hsd t h \"] h \4� e � m ] � w�]z{3]zt c3d�� ]z\ m rn\"wc3d ] g r mBhkc \"� � � ]z{V] g�mil ]?tk]?���?u mBl ] g ] d£cVg�m&g ] d"g ]z�i]z\ m ��r��i[�}"� m rV\ mBh {V];� m r g9mBh \ j�d£c3h \ m��� l ]Fw c _ [ � ]z\ m _ rV\²}�]F["��]zx®["t mBc w"]�{3]?t c3d ] g � c x � e � m ] � �¶� hÂmBl _ gihÂmBh _ rVt g ]� '[ hkg ] � ]z\ m � � q m _ rV\

rVtk� c }�]�["�i]�x®["t h \ _ c \"\"] _ mBhkc \Ã� hkmil rn\ eVc \"]��NrV\ mBh \ j�micFm ]?r _ l�cVg ts]�r g \ mBl ]�}�rV� h _ � c x)� e � m ] � rn\"w\"] m � c3g�� ��[ g { h {Vrn} h t hkm�e3� � l ]F� g��;e p¯]z�i]?r g _ l ��rV} c3g r mic3g�e rV\"w mil ]�o c x m �½r g ] � \ j3h \"]?] gih \ j q�\"� mBh �m [ m ] l r�{3]D� d�c \"� cVg ]?w�� c3g�� � l"c3d � c \µq�\�x c3g�� r mihsc \�o§[ g { h {nrV} h t hÂm�e ~®q�\�x c o§[ g { ��� q�\ d r g9m rn�#r g ]z�i["t mc x � rV[�t ¿ rVt _ � r ��� ��]z» c3g9m �Zr m ��p¯� g ]?tsr mBh \ jªmBc©mBl�h � d"g�c�� ] _ m uN��]z{V] g rnt¯[�\ h {V] g � hkmih ]?�µ~ � r g9e tsrV\"w1u� ]z\"\"� e tÂ{nrV\ h r§u � ]?\�\"]?���i]?]��°�\ c ¢P{ h tstk]Vu � ] c3gijVh r � ] _ lR�;l rT{V] l rVw _ c [ g �i]z��["� h \ jªmBl ] _ c \ m ]z\ m � c xc [ g¶h \ m ] g�hs� ± g � m � d"l rn�i] g ] d�c3g9m ~KY3rV\'[�r g9e �T�3�3� ��� � d"d ]?\"w h ¢�� _ l r g r _ m ] gih�� ]?�D� c3� ] c x mil ] _ [ g �gih _ ["tk[ ��h �i�i[�]?� g ]?tsr mBh \ j�mBc �i[ g { h {nrV} h t hkm�eV��¿ ] l r�{3] h \ m ]z\ mihsc \"rVtst e \ cnm¯migih ]?w mBc � d ]ztst c [ m � d ] _ h ± __ c [ g ��] � r m ] g�h rVtk��tk] _ m [ g ]�} e ts] _ m [ g ]Vu�}�[ m�g r mil ] g;l r�{3] mBg�h ]zw mBc©d"g�c { h w"] }�rV� h _ w hsg ] _ mihsc \"� mBl r m�i[ _ l _ c [ g ��]?� �­hkj3lfm rVw"w g ]?��� �� gih \ m rV}"tk]¯{V] g � hsc \�� c x mBl"h �Nw c _ [ � ]z\ m _ c \ m r h \ì�p����Nx c3g5� rn\ e­g ]zts]�{Vrn\ m5¿ ]z} g ]z� c [ g _ ]z� � � l ]

} g�c �&�irV}"tk] lfmB� t�{V] g � hsc \ � r e }�] d�g ]zx®] g rV}�ts]�x c3gD¿ ]z} ["�i] g �zu�}�] _ rV["��] hkm _ c \ m r h \"� l�cVm t h \ � � micmBl�c �i] g ]z� c [ g _ ]z� �

Page 4: Practical Architectures for Survivable Systems and Networks (Phase

� �

Page 5: Practical Architectures for Survivable Systems and Networks (Phase

� ����� � �����

8DQ�>�¼<�3> H

AN<�� L®>«E ����E�J£ST>PJ£ST= HKH H

� HK=zSZE �¯AN<�� L >P= ��H H

� HK=zSZE �¯GIH�����Q¸>§= ��HKH H

��� >����S¸H��£>���� ��� <"Q"! H �� l ] � g�c }"tk] � �D���D�D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� h ¢�¶c rVts� ���D�D���D���D�D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ¢ h� d"d�gic r _ l�c x mBl ]Dp&] d�c3g�m �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ¢ hp¯] _ c3�Z� ]?\"w�r mBhsc \"� �D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ¢ hsh� g _ l"hkm ] _ m [ g ]�rV\"wµq �Zd ts] � ]z\ m r mBhkc \ �D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ¢§{aNc \ _ ts["� hsc \"� ���D���D�D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ¢§{

# $ J�STQ¸E&% �'VS¸H®E�J #� � � � gic�� ] _ m#�¶c rVts� �D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �� � ^ ¡ ["\"w�r � ]?\ m rVt aNc \ _ ] d�m � �D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ^

� � ^ � � oP[ g { h {nrV} h t hÂm�eÃ�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ^� � ^ � ^ � m�mBg�h }"[ m ]?� c x o e � m ] � o§[ g { h {nrV} h t hkm�ey�D�D���D���D�D���D�¶���D���D�D���D���D� W� � ^ � W � g [�� m � c3g�mil"h \"]z�i�zu�¨�] d ]z\"w�rV} h t hÂm�e u"rn\"wy�#�i��[ g rn\ _ ] ���D�¶���D���D�D���D���D� �� � ^ � � � ]?\�] g rnt h�� ]?w aNc3�Zd£c � hkmihsc \ �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �� � ^ � � � ]?\�] g rnt h�� ]?wµ¨�] d ]?\�w"]?\ _ ] �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �� � ^ � � oP[ g { h {nrV} h t hÂm�e � hkmBl«� ]?\"] g rVt h�� ]zwy¨�] d ]?\"w�]?\ _ ] �D�D���D�¶���D���D�D���D���D� �¸^� � ^ �   � rV\"w�r mic3g�e � c t h _ h ]?�Nx cVg o§] _ [ gihÂm�e uRq�\ m ] jVgihkm�e uRrV\"wy��{nr h t|rV} h t hÂm�e/�D���D���D� �TW� � ^ � � � ["t mih ts]�{3]zt�o§[ g { h {nrV} h t hkm�e«���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���

� � W aNc3�Zd"gic3�Zh � h } h t hÂm�e rV\"w ��c \ _ c3�Zd"g�c3�­h � h } h t hkm�e²�D���D���D�D���D�¶���D���D�D���D���D� �¸�� � � ¨�]zx®]z\"�i]z��� j r h \�� m�aNc3�Zd"gicV�­h �i]?� �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �T�� � � o c [ g _ ]z� c x�p h � � � ���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ^VX� � � o c3� ]¶p¯]zts]�{Vrn\ m�a rn�i])( h � mBc3g�h ]z� ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ^3^

� � �

Page 6: Practical Architectures for Survivable Systems and Networks (Phase

� �   a rV["��]?��rV\"w � »£] _ m � �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ^V�

� A;:�Q¸>P<§S¸=�S�E ���)Q"��H��"<�� H LKH S ! � �^ � � � l"g ]?r m � mic o§] _ [ g�hkm�e �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� Wf^

^ � � � � ´�e§d rV�i��]?� ���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� W3W^ � � � ^ � ]?� m � gicVj3g r � � ���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� W3�^ � � � W p&]?� c [ g _ ] � h ��["�i] ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �fX^ � � � � aNcV�­d r gih � c \ c x � mim r _ � � c w"]?� �¶���D�D���D���D�D���D�¶���D���D�D���D���D� �fX^ � � � � � ] g � c \�rntÂ� aNcV�­d [ m ] g��#hsg ["�i]z� �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �'^^ � � � � º#mil ] g � mim r _ � � ] mBl"c w"� ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �fW

^ � ^ � l"g ]?r m � mic p&]?t h rV} h t hÂm�e²���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�^ � W � l"g ]?r m � mic � ] g x cVgi� rV\ _ ] ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �f�^ � � � ] g � d ] _ mBh {3] c \ � l�g ]�r m � mBc o§[ g { h {nrV} h t hkm�e ���D�D���D���D�D���D�¶���D���D�D���D���D� �f�

� M >����)H Q¸>��4>PJ£S¸=F<�J'%�A;:�>PH Q $ J�ST>'Q %�>'O�>PJ %�>PJ 3> ���W � � o§[ g { h {nrV} h t hkm�e rV\"wµq m ��o§[�} g ]� P[ hsg ] � ]z\ m � �¶���D�D���D���D�D���D�¶���D���D�D���D���D� �VX

W � � � � oP[ g { h {nrV} h t hÂm�e�aNc \ _ ] d�m � ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3^W � � � ^ oP] _ [ gihkm�e ���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �VWW � � � W p&]?t h rV} h t hÂm�e rV\"w ¡ rV["t m � c ts] g rV\ _ ] ���D�D���D���D�D���D�¶���D���D�D���D���D� �V�W � � � � � ] g x c3gi� rV\ _ ] �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �V�

W � ^ o e � m ] � p&]� '[ hsg ] � ]?\ m �Ix c3g oP[ g { h {nrV} h t hÂm�e ���D�D���D���D�D���D�¶���D���D�D���D���D� �3 W � W ��o e � m ] ���h ]z� c x�oP[ g { h {nrV} h t hÂm�e �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3XW � � � r d"d�h \ j � h �i� hkc \µp¯]� '[ hsg ] � ]?\ m � h \ mic o d ] _ h ± _ � �D���D�D���D�¶���D���D�D���D���D� �f^

� � !�=zST>�� H� $ J�< %)>�����< fH®>P= ��� � � o e � m ] � rV\"w � ] m � cVgi�'h \ j ¨�]z± _ h ]z\ _ h ]?� �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3W� � ^ ¨�]z± _ h ]z\ _ h ]?� h \ mil ]¶q�\�x c3gi� r mihsc \Ãq�\�x g rV� mig [ _ m [ g ] ���D���D�D���D�¶���D���D�D���D���D� �3�� � W º#mBl ] g ¨�]�± _ h ]?\ _ h ]z� �¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �f 

� O O)Q¸ER< n:�>P= �vE�Q�� ��>PQ 3E�� H J'���Ã>�� fH®>PJ fH®>P= ���� � � aNc \ _ ] d�m [�rVt)¬�\"w�] g � m rV\�w h \ j rV\"wµp&]� '[ hkg ] � ]?\ m � �D���D�D���D�¶���D���D�D���D���D�  §�� � ^ o e � m ] � rV\"w � ] m � cVgi�'h \ j � g _ l"hkm ] _ m [ g ]?� �¶���D�D���D���D�D���D�¶���D���D�D���D���D�  §�� � W o e � m ] � ¥ � ] m � c3g��'h \ j � gicVmic _ c ts�&rV\�w aNc3�Zd�c \"]?\ m � ���D�D���D�¶���D���D�D���D���D�  3^� � � aNc \�± j [ g r mihsc \ � rn\�r j ] � ]z\ m&�D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  n�� � � q�\�x c3g�� r mihsc \�q�\�x g rV� mBg [ _ m [ g ] �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  n�� � � o e � m ] � ¨�]z{V]?t c3d"� ]?\ m � g r _ mih _ ] ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  3�� �   o c x m �Nr g ] � \ j3h \"]?] gih \ j � g r _ mih _ ] ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  V�� � � o§["}"� e � m ] � aNc3�­d�c �irV} h t hkm�e �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  3 � � � ¡ c3gi� rVt � ] mBl�c w"� ���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  V�� � �TX � c �Nr g w�p c }"["� m�º�d ]?\§� ´Nc ¢�o c x m �Nr g ] �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���

� � �TX � � ´ t|r _ � � ´5c ¢µo c x m �Nr g ] �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���� � �TX � ^ º�d ]?\§� ´Nc ¢ ~vo c [ g _ ]��¼��{nr h tsrV}"tk] � o c x m �½r g ] �D���D�D���D�¶���D���D�D���D���D� �f^� � �TX � W ¬¯�i] c x aIº � o«o c x m �Nr g ] h \ aNgihkmih _ rVt�o e � m ] � � �D�D���D�¶���D���D�D���D���D� �3�

� � �3� q�\ m ] jVg r mih {3] � r g rVw hsj3� � �D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�

���

Page 7: Practical Architectures for Survivable Systems and Networks (Phase

� � �¸^ ¡ rV["t m � c tk] g rV\ _ ] ���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3X� � �TW�o m r mBh _ o e � m ] � �#\�rVt e � h � �D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���� � ��� º�d ] g r mihsc \�rnt � g r _ mBh _ ] ���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���� � �¸�bp¯]?rVtÂ� mBhk� ]¯�#\�rnt e � h � c x ´ ] l r�{ hsc3g rV\�w«p&]?� d£c \��i] �D���D�D���D�¶���D���D�D���D���D� �f^� � �T��o m rn\"w�r g w"� ���D�D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �f^� � �¸ bp¯]z�i]?r g _ l rV\"wµ¨�]z{V]?t cVd"� ]z\ m­�D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3W� � �T� � w"[ _ r mBhsc \�rn\"w � g r h \ h \ j ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �f�� � �T� �¶c {V] g \ � ]z\ m#º�gij rV\ h�� r mBhkc \"� �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �f�

� �"<"L ��<�S¸H®E�J ��QnH ST>'Q�H < ���

� Q n:)H®S�> VS"�)Q¸>P= �¼ERQ ���)Q"��H��"< �¾H LKH S ! # ���  � � o mBg [ _ m [ g rnt º�g�j rV\ h��?h \ j � gih \ _ hkd ts]z� �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TX§�  � ^ � g _ l"hkm ] _ m [ g rnt)o mBg [ _ m [ g ]z� ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TXV�  � W � g _ l"hkm ] _ m [ g rnt aNc3�­d�c \"]z\ m � �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�V�

  � W � � oP] _ [ g ] º�d ] g r mBh \ j o e � m ] � � ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�V�  � W � ^ � \ _ g�ePd�mihsc \�rV\"w�°�] e � rn\�r j ] � ]z\ m²�D�D���D���D�D���D�¶���D���D�D���D���D� �3�T^  � W � W ��[ mBl ]?\ mBh _ r mihsc \�o§["}�� e � m ] � � �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3��W  � W � � � g [�� m ]zw � r mBl �¯rV\�w«p&]?� c [ g _ ]�q�\ m ] j3g�hkm�e����D���D�D���D�¶���D���D�D���D���D� �3�?�  � W � � ¡ h ts]�o§] g {3] g � �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�?�  � W � � � r � ]Do§] g {3] g � ���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�?�  � W �   ¿ g r d"d ] g � �¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T�  � W � � � ] m � c3gi� � g�cVmBc _ c tk� �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T�  � W � � � ] m � c3gi� oP] g {V] g � �D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T�  � W � ��X ¡ hsg ]��½rntsts�½rV\"wµp c [ m ] g � ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T�  � W � �V� � c \ hkmic3gih \ j �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3���  � W � �T^ � g _ l"hÂm ] _ m [ g rVt aNl rntsts]z\ j ]z� �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T   � W � ��W º�d ] g r mBhkc \�rVt aNl rVtstk]?\ j ]?� ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3�T 

  � � � l ] � c } h ts]�� aNc w"]�� g _ l"hkm ] _ m [ g rnt � r g rVw hsjV� �D�D���D���D�D���D�¶���D���D�D���D���D� �3���  � � � � aNc \�±�\"]zw � ¢§] _ [ mBhsc \ � \f{ hsgic \ � ]z\ m � �D�D���D���D�D���D�¶���D���D�D���D���D� �¸^P�  � � � ^ p&]z{ c _ r mBhkc \µrV\"w º } � ] _ m�a [ gig ]z\ _ e �D�D���D���D�D���D�¶���D���D�D���D���D� �¸^V^  � � � W � g�c§c x|� a r gig9ePh \ jZaNc w"] �D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸^nW  � � � � � g _ l"hÂm ] _ m [ g ]?�¯� _z_ c3�Z�Zc w�r mBh \ j ¬�\ mBg ["� m � c3g9mBlfe � c } h ts] aNc w"] �D���D���D� �¸^nW

  � � � l ] � c3g9m rV}�ts]�� aNc3�Zd [ mBh \ j � g _ l"hkm ] _ m [ g rVt � r g rVw hkj3� �D�D���D�¶���D���D�D���D���D� �¸^nW  � � o mBg [ _ m [ g rnt�� g _ l�hkm ] _ m [ g ]z� ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸^��

  � � � � aNc \'{V]?\ mBhkc \�rVt�� g _ l"hÂm ] _ m [ g ]?� ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸^��  � � � ^ � ["t mih ts]�{3]zt�o§[ g { h {nrV} h t hkm�e � hkmil � h \ hk�­h�� ]zw � g ["� m � c3g�mil"h \�]?�i� �D�D���D���D� �¸^��  � � � W � \"wP�¬���] g o e � m ] � aNc3�Zd£c \"]?\ m � �¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸^V 

� $ � O¾L®>��4>PJ£S¸H J'�²<�J'% ��E£J � � ��Q�HKJ ���¼ERQ �&��Q"��H ��<�� HKL H®S ! # � �� � � ¨�]z{V]?t cVd"h \ j oP[ g { h {nrV}�ts]Do e � m ] � � �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TWVX� � ^ ��o mBg r m ] jVe x c3g oP[ g { h {nrV}�ts]�� g _ l"hkm ] _ m [ g ]?� ���D�D���D���D�D���D�¶���D���D�D���D���D� �TW§�� � W ´ rV��]?t h \"]Do§[ g { h {nrV}"tk]�� g _ l�hkm ] _ m [ g ]z� ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TWVW

Page 8: Practical Architectures for Survivable Systems and Networks (Phase

� ��E£J'fL�� =�H®E�J = # � �� � � p¯] _ c3�Z� ]?\"w�r mBhsc \"�Nx c3g½mil ] ¡ [ m [ g ] ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TWV�� � ^ p¯]z�i]?r g _ l rV\"wµ¨�]z{V]?t cVd"� ]z\ m ¨ hkg ] _ mBhkc \"� �¶���D�D���D���D�D���D�¶���D���D�D���D���D� �TW3 � � W ��]?�i� c \"����]�r g \"]?wyx gic3� � rV� m#� ¢ d ] gih ]?\ _ ] ���D�D���D���D�D���D�¶���D���D�D���D���D� �TWV�� � � � g _ l"hkm ] _ m [ g rnt�¨ hsg ] _ mihsc \"� ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ������ � � � ]z� m }£]zw«� _ mBh { hÂmBh ]?� �¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ������ � � p¯]z� h w"[�rVt � [�ts\"] g rV} h t hÂmBh ]z�½rV\�w�p h � � � ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���f^� �   � d"d t h _ rV} h t hkm�e�mic�mBl ] � aIa q � p¯] _ c3�Z� ]z\"w�r mihsc \�� �D���D�D���D�¶���D���D�D���D���D� ���f^� � � ¡ [ m [ g ] ¿4cVgi�«�D�D���¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���3W� � � ¡ h \"rVt aNc3�Z� ]?\ m � �¶�D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���V�

� J)EPC­L >�% � � >§J�S¸= # ��

O)O�>§J'%)H � �� � ��Q�Q�H��� L®<��¼ERQ ����Q ��H ��<��¾H L H®S ! # � �� � �FoP[ g { h {nrV} h t hÂm�e �p&]?ts]�{nrV\ m&aNc [ g �i]z� ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���f � � ^�� d"d t h _ rn} h t hkm�e�c x¾p¯] �­cnm ]D��]�r g \ h \ j rn\"w aNc tst|rn} c3g r mBh {3] � ]?r _ l"h \ j �D���D�D���D���D� �¸�P�� � W�oP[ �­� r g9e c x � w"[ _ r mBhsc \�rn\"w � g r h \ h \ j�� ]z]?w"� �D���D���D�D���D�¶���D���D�D���D���D� �¸�nW� � � � l ] � [ g�d£c �i] c x � w"[ _ r mihsc \ ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸�nW

O)O�>§J'%)H ��� ��� E£J�<�S¸:�<�J�� H LKL®>PJÂ=FM >P=?>'<"Q �: �;E�J£S�QnH � ��S¸H®E�J = # ���

O)O�>§J'%)H � � � �ÃE � S�ST>��4O�S¸=F<�S ��S�<�J %�<"Q %)H��f<�STH E�J # � �a#� � � l ];Y c3h \ m � ] _ l \ h _ rnt�� g _ l�hkm ] _ m [ g ] �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸�V 

a#� � � � ��c rVts� c x�Y � � � ] g � hsc \�� � X �D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸�V a#� � � ^F�#\"rVt e � h � c x�Y � � � ] g � hsc \«� � X ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸�n�a#� � � WZY � ��� � X�oP] _ mihsc \���u"q�\§x c3gi� r mBhkc \yo§] _ [ g�hkm�e«���D���D�D���D�¶���D���D�D���D���D� �T�VXa#� � � ���#[ j3� ]z\ mBh \ j�mil ]¶� g��;e � g _ l"hkm ] _ m [ g ] aNc \ _ ] d�m#�D�D���D�¶���D���D�D���D���D� �T�3^

a#� ^ � l ]�¨ c ¨ �¶c rVt�o§] _ [ g�hkm�e � g _ l"hÂm ] _ m [ g ] �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �T�VWa#� W­Y c3h \ m � hsg } c3g \"]Do§q � q � � � g _ l�hkm ] _ m [ g ] �D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �T�n�

O)O�>§J'%)H � � � ��E � >� �E�ST>fC;E�QTS¸:�!�M�>��v>PQ¸>PJ'3>§= # �

� H �¾L H E �RQ¸<"O : ! # ��

$ J %�> � � � #

� �

Page 9: Practical Architectures for Survivable Systems and Networks (Phase

� � � � � � � ��� � � �

� � � q�tstk["� mig r mih {3] aNc3�­d�gic3�Zh ��]?� ���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �T�^ � � � ePd ]?� c x aNc3�­d [ m ] g � h �i[��i] �D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� Wf�^ � ^ q�tstk["� mig r mih {3]�p¯]zt h rn} h t hkm�e � l"g ]�r m � ���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �'�W � � o c3� ]Do§[ g { h {nrV} h t hkm�e � mimigih }"[ m ]z�¯r m ¨ h »£] g ]z\ m � cVj3h _ rVt1��r e ] g � �¶���D���D�D���D���D� ���� � � ¨�]zx®]z\"� h {3] � ]�rn�i[ g ]?� �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D�  VX  � � � ePd"h _ rVt�� g _ l"hÂm ] _ m [ g rVt�� hs�Zhkm r mBhkc \"� ���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �3���  � ^ � g _ l"hkm ] _ m [ g rnt � ]?]zw"� �D���D���D�D���D���D�¶���D�D���D���D�D���D�¶���D���D�D���D���D� �¸^V�� o§[ g { h {nrV} h t hkm�e�a [ g�gih _ ["ts[ � aNc3�Zd£c \"]?\ m � �¶���D�D���D���D�D���D�¶���D���D�D���D���D� ���3�

� � �

Page 10: Practical Architectures for Survivable Systems and Networks (Phase

� � � � � � � ����� ��� �

^ � � a t|rV���i]z� c x aNc3�Zd [ m ] g � h �i["��] � ] _ l \ h '["]?� ���D�D���D���D�D���D�¶���D���D�D���D���D� WV�W � � q�tstk["� mig r mih {3]�o§["}"��] m�c x p&]� '[ hkg ] � ]z\ m � ( h ] g r g _ lfe �D���D�D���D�¶���D���D�D���D���D� �§�

��� � �

Page 11: Practical Architectures for Survivable Systems and Networks (Phase

� � � � � � ��� � � � � � � ���

� ���0�����N$���)(

o e � m ] � ��rV\"w�\"] m � c3g�� ��� hÂmBl _ g�hkmih _ rnt§��[ g { h {nrV} h t hÂm�e¶g ]� P[ hsg ] � ]z\ m ��r g ]N]�¢ mBg ] � ]?t e w h _ ["t m mBc � d ] _ �h x e u3w"]�{3]?t c3d u d"g�c _ [ g ]nu cVd ] g r m ]Vu'rV\"w � r h \ m r h \ � � l ] eFm ]z\"w mBc }�]I�i["} � ] _ m mBc¶� rV\ e;mil"g ]?r m �zuft|rVw"]z\� hkmil�g�h � � �zu�rn\"w«w h� _ ["t m¯mic [��i]�� h �i]zt e3�½´5e ��������������� �5] h \ _ tk["w"] c3d ] g r mBh \ j � e � m ] � �zu�w"]zw h _ r m ]zwr d"d t h _ r mBhkc \ � e � m ] � �zu�� e � m ] � � c x � e � m ] � �?u�rV\"wµ\"] m � c3g�� ��{ h ]��N]zw«rV�&� e � m ] � � �¿ ]D}�] jVh \ � hkmil ��]z{V] g rnt c }"�i] g {nr mBhkc \"� �

� aNcV�­� ] g _ h rntst e r�{Vr h t|rn}"ts] � rV�i�� � r gi� ] m � c x m �Nr g ]N� e � m ] � � m ]z\"w mBc }£]N{V] g9e;d�c§cVg � hÂmBlFg ]?� d ] _ mmic ��] _ [ gihkm�e rV\�w g ]zt h rn} h t hkm�e3� � l ] e r g ]�]�{3]z\b� c3g �i]«� hÂmBl�g ]?� d ] _ m mic4c {3] g rVtkt&� e � m ] � rn\"w\�] m � c3gi� ��[ g { h {Vrn} h t hkm�e uI� l"h _ l w"] d ]?\"w�� _ gihÂmBh _ rVtst e c \��i] _ [ g�hkm�e rV\�w g ]?t h rV} h t hÂm�e3� o c x m �½r g ]_ c3�Zd£c \�]?\ m �)r g ] c x m ]?\ h \ _ c3�Zd r mBh }"ts] � hkmBlDc \"]5rV\ cnmBl ] g u�]z{3]z\F� l ]?\ c } m r h \"]zwDx g�c3� mil ]5�ir � ]w�]z{3]zt c3d ] gz� q�\ m ] g�c3d ] g rn} h t hkm�e rV\�w g ]z["�Brn} h t hkm�e r g ] � [ _ l ts]z�i� mBl rn\«� l r m � l"c ["tsw g ]�rn� c \�rn}"t e}�]µ]�¢ d ] _ m ]?w � aNc3�­d r mBh } h t hkm�e � hÂmBl ts] j r _ e � e � m ] � � h �­w gih { h \ j � rV\ e � e � m ] � � h \ mic�mil ] hkgt c �N]z� m _ c3�Z�Zc \�w"]?\ cV�­h \�r mBcVg � � � gic3d"g�h ] m r g9e � e � m ] � �Nrn\"w d�gic3d"g�h ] m r g9e�h \ m ] g x r _ ]&� m rn\"w�r g w"�j ]?\"] g rVtkt eF� r � ] h \ m ] j3g r mBhkc \F� hkmil�cVmil ] g � e � m ] � m�ePd ]?� {3] g9e w h _ [�t m�� � l ] e rVtk� c¶� r � ] c3d ]z\rn\�rVt e � h � c x mBl�c �i]y� e � m ] � ��{3] g�e w h� _ ["t m ~ d"g�c3�­cnmBh \ j �i] _ [ g�hkm�e } e c }"� _ [ g�hkm�e g r mBl ] gFmBl rV\��] _ [ gihÂm�e } eÃh \P��w"] d�mBl rV\"rVt e � h � ��� � c \ j � m ] g�� _ c3�­d r mBh }"ts]�]z{ c tk{nrV} h t hkm�e�h �&rF�i] gihsc ["� d"gic }"ts] ���� l ] g ]?rV� c \��;x c3g¶mBl"h � c {3] g rVtktN� hÂm [�r mBhsc \4r g ]­� h w"]?� d"g ]?rVw1u�rV\"w mil ]�}�t|r � ] � ["� m }�]�� l r g ]?wr �­c \ j w"]z{V]?t cVd ] g �?u j3c {3] g \ � ]?\ m �?u�["�i] g _ c3�Z� ["\ hÂmBh ]z�?u h \�rVw"]� '[�r m ] d"g�c _ [ g ] � ]z\ m#d"g�c _ ]?���i]?�zurn\"w mBl ]¶t|r _ � c x � r g�� ] m&h \ _ ]?\ mBh {3]?�;~®x cVg ]�¢�r �Zd ts] ���

� � l ]F¬ � o ���¶c {V] g \ � ]z\ m rV\"w mBl ]�w"]zx®]z\"�i]F]z� m rV}"t h � l"� ]?\ m�l r�{3]F}�] _ c3� ] h \ _ g ]�rV� h \ j t e w"] d ]z\§�w�]?\ m�c \ _ cV�­� ] g _ h rntst e r�{nr h tsrV}"ts]�� e � m ] � ��� � hkmBl rVtst mil ] hkg �½r g9m �zuI}"ts] �­h � l ]z�?u½rn\"w�x®["\P�w"r � ]z\ m rVt � l"c3g9m _ c3�­h \ j � � ¬¯\�x c3g�m ["\�r m ]?t e u � rV\ eªc x mil ]?��]Z� e � m ] � �Dr g ]�\ cVm rnw�{nrV\ _ h \ j x rV� m]z\ c [ jVl mic � ]?] mZmil ]y\"]?]zw"� c x _ gihkmih _ rVtIr d"d t h _ r mBhkc \"� � � d£c ��� h }"ts]µrVt m ] g \�r mih {3] x cVg _ gihÂmBh _ rVtr d"d t h _ r mihsc \�� h � j r h \ h \ j � c3� ] _ g ]?w h } h t hkm�e �)� c3� ]#� c3g�mNc x�w h � _ hkd t h \"]?wZ]z» c3g9m � micF� r � ] _ ] g9m r h \� c [ g _ ]���r�{Vr h t|rn}"ts]F� c x m �Nr g ] _ c3�Zd£c \"]?\ m �D�i[�}"� m rV\ mBh rntst e«�­cVg ] gic }�["� m u rV\"w mBcµj ]?\�] g r m ]Z\"]z�_ c3�Zd£c \�]?\ m ��� d r g9mBh _ ["tsr g t e � l ] g ] d"g�c3d"gih ] m r g�eyc »R� mil ]��¼� l ]ztkx d�gic w"[ _ m ��r g ];\ cVm rVw"]� P["r m ] �( c �N]�{3] g u mBl r m r d�d"gic r _ l l rV� hkm � c �&\ d�cVm ]z\ mBh rnt g�h � � �zu � l"h _ l w"]z�i] g {3] mic }�]­� m ["w h ]?w rn\"wc {V] g _ c3� ]¶� l ] g ] d�c �i� h }"tk] �

� o e � m ] � w"]�{3]?t c3d"� ]?\ m�d"g r _ mih _ ] h � h \ j ]z\"] g rVt�rV} e � � rVt � ~ p¯] _ ]?\ m ]�¢"r �­d tk]?� c x�±RrV� _ c � g ]zt|r mih \ jmic ¬ � o �&��c {3] g \ � ]?\ m � e � m ] � w"]z{V]?t cVd"� ]z\ m � h \ _ ts["w�] mBl ] _ rV\ _ ]?tkt|r mihsc \"� c x mBl ] ¡ �#� � hsgp c [ m ] � g r _ aNc \ migic tDo e � m ] � _ c \ mBg r _ m u mBl ]�qp�o � r�¢ o e � m ] � � � c w�] g \ h�� r mBhsc \ ]�» cVg�m u

���

Page 12: Practical Architectures for Survivable Systems and Networks (Phase

rn\"w mil ]Z± g � m ¡ ´ q �#a q a �9^VXVX3Xµ±�\ j ] g�d"gih \ m � e � m ] � u g ] d"g ]?�i]z\ mBh \ j«mBl ]��NrV� m ] c x½} h tst hsc \�� c xw c tstsr g � �À� � g ] d"g ]z�i]z\ m r mBh {3]�]�¢�r �Zd ts] c x mBl ]ª{V] g�e }"rVw � m r m ] c x d"g r _ mih _ ]ªrV\"w mBl ] jVg ]�r mw h _ ["t mBh ]?� h \ l ] g ]?\ m�h \ mBg9ePh \ j�mBc rVw�{nrV\ _ ] mBl ]&� m r m ] c x _ c3�­� ] g _ h rVt�� e � m ] � � h � j3h {3]z\­} e�mBl ]� ] g ]5]�¢ h � m ]?\ _ ]IrV\"w d ] g {nrV� h {3]z\"]?��� c x mil ] � ]?r g �^VX3X3X d"gic }"ts] � u¸� hkmil�mBl ] g ]z�i["t mBh \ j ]z\ c3g��­c [��_ c � m � mic ±�¢ } h tst hsc \"� c xIt h \"]?� c x _ c w"] h \ mil ] d�g ]?��]?\ _ ] c xNt h \ j ] g�h \ j w c [�} m �;rV� mic � l ] mBl ] gmil"c ��] r m�m ] �Zd�m �D� c ["tkw4}�]­��[ _?_ ]?�i�9x®["t½[ d mBc rn\"w4]�{3]?\ r�x m ] g¶mBl ] r _ m [�rVt ]�{3]?\ m?� � l ] � ^V°d�gic }"tk] �*h � � ["� m½c \"] �Zc3g ]#]�¢�r �Zd tk] c x�� l"c3g�m ��� hsj3lfm ]zw � e � m ] � w"]z{V]?t cVd"� ]z\ mId"g r _ mBh _ ]nu g r mBl ] gmil rV\+r ["\ h '["] d"g�c }"tk] � ["\ mBc4hkm ��]?tÂxu½rV\"w h � g ]?rVt h � mBh _ rVtkt e ts]z�i� _ c3�Zd ts]�¢ mBl rV\ mBl ] c {3] g rVtst��] _ [ gihÂm�e ¥��i[ g { h {nrV} h t hkm�e­d"gic }"ts] � � �

� � l ] g rV\ j ] c x d�cVm ]z\ mBh rnt mBl�g ]�r m � mic �i[ g { h {nrV} h t hkm�e©mil r m�� ["� m }�] _ c \"� h w"] g ]?w h ��]?\ cVgi�Zc ["�?uh \ _ tk["w h \ j�l r g w��Nr g ] � rVtkx®["\ _ mBhkc \"�zuP� c x m �Nr g ]#³�rT�&�zu"]?\f{ hsg�c \ � ]?\ m rnt l r � r g w"�?u�rV\"w � rVt h _ hkc ["�rn\"w r _?_ h w"]?\ m rVt l [ � rV\ r _ m � � � l ]4tk]z{V]?t c x�r��Nr g ]z\"]?��� c x mBl"g ]�r m �?u�{P["tk\"] g rV} h t hkmih ]?�zu#rn\"wg�h � � � h � j ]?\�] g rntst e w"] d t c3g rn}"ts] � º »�]z\"� h {3] h \�x c3g�� r mihsc \F�Nr g x r g ] h ��}£] _ c3�Zh \ j�g ] _ c3j \ h�� ]zw rV�Nr��] g�hsc ["� d£cVm ]?\ mBh rVt mBl"g ]�r m mic �i[ g { h {nrV} h t hkm�e un}�[ m r mim ] �Zd�m � mBc w"]�{3]zt c3d _ cVgig ]z� d�c \"w h \ j w"]�x®]?\"��]?�r g ]µt|r j3jVh \ j }�rVw�t e3� ¨�]zx®]z\"� h {3] h \�x c3g�� r mBhsc \ �Nr g x r g ]µ�i]z] � � mBc }£]«r �­h �i\ cV� ] g x cVg � l r m� l"c ["tkw cVmBl ] g � h �i]¶}£] _ c \"� h w"] g ]?w d ] g {nrV� h {3]zt e rn�¯��]?\"� h }"tk]¶� m rn\"w�r g w d"g r _ mih _ ]V� h x)�5]¶�5] g ] micw�]z{3]zt c3d rV\"w�["��]½� e � m ] � � rV\"wF\�] m � c3gi� � mBl r m r g ] � ]�rV\ h \ j x®["tkt e �i[ g { h {nrV}"ts]nu3�i] _ [ g ]Vu g ]?t h rV}"tk]Vurn\"w©� cÃc \�u hkm � c ["tsw©w g r � r mBh _ rVtkt e w"] _ g ]�rV��] mBl ] mil"g ]?r m � c x c »�]z\"� h {3] h \�x c3gi� r mihsc \y�½r g x r g ]r j r h \�� m [�� � � rn\ e;c3gij rV\ h�� r mBhkc \"�N~ d ] g�l r d � �Zc � m { h � h }"t e u mBl ] � ]z\ m r j3c \ �¾l r�{3]&}£]z]?\�w"]zts[ j ]zw� hÂmBl r m�m r _ � � c \ mBl ] hsg ¿ ]z}­� hkm ]z� rV\"w _ cV�­d [ m ] g � _ c3�­� ["\ h _ r mBhkc \ h \�x g rn� mBg [ _ m [ g ]z�?u h \ _ ts[�w h \ jd ]?\�] mBg r mBhkc \"�zunw"]z\ h rnts� c x"��] g { h _ ]Vu3rV\"w � gic�� rn\ l"c3g �i]z�¾�i[ _ l rV� � ]?t h �i�ir#rV\"w�q� º ��� � º ¬ mBl r md�gic3d r j r m ]­} e d ] c3d tk] g ]�rVw h \ j ]�� � r h t � ��\"w e ] m {3] g9e x®]�� ��["}"� m rV\ mBh {3]µr _ mBhsc \"�Fr g ] }�] h \ jm r � ]z\ mic�hs�Zd"gic {3] mil ] h \�x c3g�� r mBhsc \ h \§x g rV� mBg [ _ m [ g ]?� m ] _ l \ c t c3j3h _ rVtkt eV�

� � l ]©�T�3�f  g ] d�c3g�mFc x mBl ] � g ]?� h w"]?\ m�� � aNc3�Z�­h �i� hsc \ c \ aNgihÂmBh _ rVt�q�\�x g rV� mBg [ _ m [ g ] � gicnm ] _ mBhkc \~ � aIa q � ��mBc [ _ l ]?� c \ mBl ] mihsd�c x&rV\ ]?\ c3g��­c ["� h _ ]z}£] gij"� q m�c }"��] g {3]?� mil r mDmBl ]Z�i[ g { h {nrV} h tÂ�hÂm�e rV\"w h \ m ] j3g�hkm�e�c x mBl ] _ gihÂmBh _ rVt�\�r mihsc \�rnt h \�x g rn� mBg [ _ m [ g ]z�µ~ ��[ _ l rV� m ]zts] _ c3�Z� ["\ h _ r mihsc \��?ud�c �N] g u ]?\"] gijVe u mBg rV\"� d�c3g9m r mihsc \1u rV\"w�±�\�rV\ _ h rnt���] g { h _ ]z� � r g ]Z{V] g9e4� [ _ l r m�gih � � u rV\�w4x®[ g �mil ] g��­cVg ] mil r m½mil ]?��]�\�r mBhkc \�rVt h \§x g rV� mBg [ _ m [ g ]?�&r g ] l"hkj3l t e­h \ m ] g w"] d ]?\�w"]?\ m¯c \ c \"]¶rn\ cVmBl ] g?�¿�l ] g ]?rV� mil ] g ] d�c3g�m g ] _ c3j \ h�� ]z� mil r m¾mil ] _ gihÂmBh _ rVtf\�r mihsc \"rVt h \�x g rV� mig [ _ m [ g ]?�¾w�] d ]?\"w _ gihkmih _ rVtst ec \ _ c3�­d [ m ] g ��rV\"w _ c3�Z� ["\ h _ r mihsc \��?u mil ] hkg¯g ] _ c3�­� ]?\�w�r mBhkc \"� mic [ _ l«c \"t e t hsj3lfm t e­c \�� l r m�ZhsjVl'm }�]�w c \"] mic � mBg ]?\ jnmBl ]z\ mil ]�["\"w�] g t ePh \ j _ c3�­d [ m ] g � _ c3�Z� ["\ h _ r mihsc \ h \�x g rV� mig [ _ m [ g ]?� �~®�#t mBl"c [ j3l4mBl ] aNc3�Z�­h �i� hkc \ � � h \ hkmih rVt x c _ ["� h \ m ]zts] _ c3�Z� ["\ h _ r mihsc \��D�NrV��\�r g�gic �&t e r hk� ]zwr m�mil ] d [�}"t h _ �9� hkm _ l ]?w©\"] m � c3g�� u mBl ] aNc3�Z�­h �i� hkc \ � � � ] � }£] g �¯w h w�["t mihs� r m ]zt e r mim ] �Zd�m�mic} gic rVw�]?\ mBl ] hsg _ c \ _ ] g \�� mic©h \ _ ts["w"] mil ]Ãq�\ m ] g \"] m rn\"w _ c3�Zd [ m ] g \"] m � c3g��'h \ j"�¦� � l ] � a �a q � g ] _ c3�Z� ]z\"w�r mihsc \���r g ] hk�­d�c3g9m rV\ m rn\"w � ["� m }�] _ c \�� h w�] g ]zw�{V] g9e _ r g ]zx®["tkt e u�rVt mil"c [ jVlmil ] g ] h �¶r m ]?\"w"]z\ _ e©mic �½r g w h \ _ g ]�rV� h \ j }�[ g ]?rV[ _ g r _ eV� ~vo§]z]­o§] _ mBhsc \4� � �T��x cVg��­cVg ] c \ mBl ]aNcV�­�Zh ��� hsc \ÃrV\"w��i["}"��]� '["]z\ m r _ mihsc \"�zu�rV\"w«o§] _ mBhkc \�� �  Fx c3gIl"c � mil"h � g ] d�c3g�m rVw�w g ]z�i�i]z� mBl ]d�gic }"tk] � � h w�]?\ mBh ±�]?wµ} e mBl ] � aIa q � g ] d£c3g9m��¦�

� ��t mil"c [ j3l � hsj \ h ± _ rV\ mFg ]?�i]?r g _ l rV\�w d"gicVmicVm�ePd ]���w"]�{3]zt c3d"� ]?\ m ]�» cVg�m � _ c ["tkw l ]?t d �Zh \ hk�­h�� ]� rV\ e c x mil ]ª]�¢ h � mBh \ j d"g�c }"tk] � ��rV\�w � rV\ e \"]�� d�gic }"tk] � � mil r m \"]?]zw mic }�]ªrVw"w g ]?���i]zw1u{nrVtk[�rV}"tk]¯p��¶¨ rVw§{Vrn\ _ ]z� g ]zt|r m ]?w mic ��] _ [ gihkm�e u g ]zt h rV} h t hkm�e ufrV\"w­�i[ g { h {nrV} h t hkm�e�l rT{V] h \ j ]?\"] g rVt}�]?]z\�]�¢ _ ]?]zw h \ j t e ��t c � h \ñ�\"w h \ j�mBl ] hsg �Nr eyh \ mBc�d"g r _ mih _ ] � � l r m¯� ["� m _ l rV\ j ] �

Page 13: Practical Architectures for Survivable Systems and Networks (Phase

� �5� ��

� l ];rV} c {V] c }"��] g {Vr mBhsc \"� �ZcVmih {nr m ]DrZ� hs�Zd tk]�� m r m ] � ]?\ m#c x mBl ] j3c rVts� c x c [ g�d�gic�� ] _ m rn\"w c x mBl"h �g ] d£cVg�m�� � c �i[ g��­c [�\ m&mil ]?��] g ]�rVt hkmBh ]?�zuP�5]���]?] � mBc� � � r � ] �Zc3g ]N]�¢ d t h _ hÂm¾mBl ] g ]� '[ hkg ] � ]z\ m ��x c3g �i[ g { h {nrV} h t hÂm�e rV\"w hkm � \"] _ ]?���Br g9e �i["} m ]?\"w�]?w d"gic3d �] g�mih ]?���i[ _ l rV���i] _ [ g�hkm�e u g ]?t h rV} h t hÂm�e u)rV\"w d ] g x c3gi� rV\ _ ]Vu rn\"w _ l r g r _ m ] gih�� ] mil ] h \ m ] g r _ mihsc \"�r �­c \ jFmBl ]¶w h »�] g ]?\ m �i[�} g ]� P[ hsg ] � ]z\ m �

^ � q�w�]?\ mBh x e x®["\ _ mBhsc \�rVt hÂm�e � l"c �i]­rV}"��]?\ _ ] _ [ gig ]?\ m t e©d"g ]z{3]z\ m �Frnw"]� '[�r m ]­�ir mBh ��x r _ mBhkc \ c x mBl"c ��]g ]� '[ hkg ] � ]?\ m ��rV\"w g ] _ cV�­� ]?\"w mBl ] w�]z{3]zt c3d�� ]z\ m�c x&� d ] _ h ± _ h \�x g rV� mBg [ _ m [ g rVt _ cV�­d�c \"]z\ m �mil r m r g ] _ [ g�g ]z\ m t ey�Zh ��� h \ j�c3g \ cVm _ c3�­� ] g _ h rVtst e r�{nr h t|rV}"tk]

W ��� ¢ d t c3g ] m ] _ l \ h '["]z� x c3g w"]z� hkj \ h \ j rV\"w w�]z{3]zt c3d�h \ j l�hsj3l t e �i[ g { h {nrV}"tk]«� e � m ] � �yrV\"w+\"] m �� c3g�� �zu£w�]?� d�hkm ] mBl ] d"g ]?��]?\ _ ] c x [�\ mig ["� m � cVg�mBlfe �i["}�� e � m ] � ��rV\"w�["\ mBg [�� m � c3g�mil'e�d ] c3d tk] �� l ] g ]5["\ mBg ["� m � c3g�mil"h \�]?�i� � r e ]?\ _ c3�Zd rV�i� mBl ]�t|r _ ��c x g ]zt h rV} h t hkm�e u h \ m ] j3gihÂm�e uVrV\"w _ c3gig ] _ m \"]z�i�c x¾}�] l r�{ hscVgIc \ mBl ] d r g9m¯c x¾� e � m ] � ��rV\"w d ] c3d tk]

� � p&] _ c3�Z� ]z\"wÃ� d ] _ h ± _ r g _ l"hkm ] _ m [ g rVt�� mBg [ _ m [ g ]?�¯rV\�wµ� mBg [ _ m [ g rVt1r g _ l"hÂm ] _ m [ g ]?� mil r m _ rV\yts]�rnwmic ��[ g { h {nrV}�ts]�� e � m ] � ��rn\"w \"] m � c3g�� � _ r d rn}"ts] c x&] hÂmBl ] g;d"g ]z{3]z\ mBh \ j©c3g�mic ts] g r mih \ j r�� h w�]g rV\ j ] c x mil"g ]?r m �

� ��� ¢ d t c3g ] c3d ] g r mBhkc \�rVt d"gih \ _ hkd ts]z� mBl r m _ rV\µ]?\ l rV\ _ ]D�i[ g { h {nrV} h t hÂm�e� � p&] _ c3�Z� ]z\"wyw hsg ] _ mihsc \��½x c3g½mBl ]�x®[ m [ g ]nu h \ _ ts["w h \ jFg ]?��]�r g _ l rV\"wyw"]�{3]?t c3d"� ]?\ m

���������5����� ��� ������� ���;�5���

q mDh �DrV}"� c ts[ m ]?t e ]?���i]z\ mih rVt mic�g ]�rVt h�� ] mil r m¶mBl ] g ]�r g ]�\ c ]�rn� e rV\"�9�N] g �;x cVg r _ l"h ]�{ h \ j �i[ g { h {nrV}"tk]� e � m ] � �yrV\"w \�] m � c3gi� � � � l"h � g ] d�c3g9m w c ]?� \ cVmÃd"g ] m ]z\"w mBc }�]©r _ c§c3� } c§cV����aNcPc3� } c§c3� r d �d"g�c r _ l ]z�Ir g ]¯w cPc3� ]?w mic x r h tvuf}�] _ rV["�i] c x mil ] h \ migih \"� h _ � ["t mih w hk� ]z\"� hkc \�rVt hkm�eDc x mil ]#��[ g { h {nrV} h t hÂm�ed"g�c }"ts] � �zu mBl ] h \�rVw"]� P["r _ h ]?� c x mBl ]�]�¢ h � mBh \ jyh \�x g rV� mig [ _ m [ g ]?�zu mil ]�x r _ m¶mil r m�mBl ]Z[�\"w"] g�d"h \�\ h \ j �r g ] _ c \ mih \'[�rVtkt e�h \4³"[§¢£u5rn\"w mBl ] x r _ mFmil r m \ c©c \"] � c ts[ mihsc \ cVg � � rVtkt5��] m�c x&� c ts[ mihsc \���± m ��rVtstr d"d t h _ r mBhkc \"� �D¿ ] _ rV\"\ cVm¶� ] g ]zt e x c tst c � migih ]zw§�rn\"w§� mig ["] g ] _ hsd ]?�zu)}�] _ rV["��]Z\ c x cPc t d"gicPc x g ] _ hkd ]z�]�¢ h � m�� ¡ c3g mil ]?��] g ]�rV� c \"�?uP�N]�] �Zd"l rV� h�� ] l ] g ] mBl ]¯\"]z]?w�x c3g h \§��w"] d�mBl ["\"w�] g � m rV\�w h \ j;c x mil ]�}"rV� h _h ���i["]z�?u mil ] g ] _ c3j \ hkmBhkc \©rV\�w d ] g {nrV� h {3]�rVw l ] g ]?\ _ ] mic �i]z\"� h }"ts] d"g�h \ _ hsd tk]?�zu mBl ]Fx®["\"w�r � ]?\ m rVt hk� �d�c3g�m rV\ _ ] c x h \�� hsjVl'm � j ts]?rV\"]zw�x g�c3� d rn� m ]�¢ d ] gih ]?\ _ ]Vu¾rV\"w mBl ]�[ g�j ]?\ _ e²c x d [ g ��[ h \ j � hsj \ h ± _ rn\ mp �D¨ r d"d"gic r _ l ]?�ZrV\�w h \ _ c3gid�c3g r mBh \ j�mBl ] � h \ mBcªd"g r _ mih _ rVtN� e � m ] � � � � l ["�?u �5] h \ _ ts["w"] � rV\ eg ]�x®] g ]?\ _ ]?� mic4d"g�hs� r g�e t hkm ] g r m [ g ]Ã� c [ g _ ]z�?uI� hkmil�mBl ] l"cVd ]z� mBl r m w h t hkj ]?\ m�g ]�rVw"] g �Z� h tst d [ g ��["]mBl ] �µ� � l ]��i[ _z_ ]?����x®["t h \ m ] j3g r mBhsc \ c x mBl ]�}�]?� m#c x mBl ]z�i] _ c \ _ ] d�m � h �¯rV}�� c tk[ m ]zt e x®["\�w�r � ]?\ m rVt micmBl ]½w"]z{V]?t c3d"� ]?\ m u d"g�c _ [ g ] � ]z\ m u'rV\"w�[��i] c xR� e � m ] � � rV\�w�\"] m � c3gi� � mBl r m _ rn\Fx®["tk±�tkt g ]� '[ hkg ] � ]z\ m �x c3gIl"hkj3l �i[ g { h {nrV} h t hkm�eV�� c �Br mih �9x eµmil ] j3c rVts�¯� m r m ]zw²rV} c {V]Vu£�5] m r � ]�r�� mBg�c \ j t e � e � m ] � � c3g�h ]?\ m ]?w²r d"d�gic r _ l�� o§[ g { h {f�

rV} h t hÂm�e«c x5� e � m ] � ��rV\"w�\"] m � c3gi� � h �¶\ cVm rV\ h \ migih \�� h _ t c �½��ts]�{3]zt d"gicVd ] g�m�e²c x5�i["}�� e � m ] � � h \ mBl ]� � rVtkt � q�\�� m ]?rVw1u hÂmIh �&rV\ ��� ��� ��� � ������� ����� � � mil r m&h �zu"r d"g�c3d ] g�m�e mil r m&l rn� � ]?rV\ h \ j�d"gihk� r g�h t eh \ mBl ] c {3] g rVtkt _ c \ m ]�¢ m;mBc � l"h _ l4hkmDg ]?t|r m ]?� � ��� ] gij ]?\ m;d�gic3d ] g9mBh ]z� _ rV\4}�]Zw"]z±�\�]?w h \ m ] gi� � c x

� �

Page 14: Practical Architectures for Survivable Systems and Networks (Phase

mBl ] _ c \ _ ] d�m � c x mBl ] hsg�c �&\ t|r e ] g � c x�rn}"� mig r _ mBhsc \1u5}�[ mZj ]?\"] g rVtkt e \ cVm _ cV�­d tk] m ]?t e4h \ m ] gi� � c xh \�w h { h w�[�rVt _ c3�Zd£c \"]?\ m ��r m t c �N] g t|r e ] g � � � l r m�h �?u�rV\ ] � ] gij ]z\ mZd"g�c3d ] g�m�e4h ��r d"g�c3d ] g�m�e mBl r mr g�h �i]z��rV��r g ]?�i[�t m�c x mBl ] _ c3�Zd�c � hÂmBhsc \ c x¯t c �5] g ��t|r e ] g _ cV�­d�c \"]z\ m ��rV\"w mil r m�h �F\ cVm�cnmBl ] g � h ��]]z{ h w"]?\ m������ ] gij ]?\ mId"g�c3d ] g�mih ]?� � r e }�] d£c � hkmih {V]�~ ��[ _ l rV� l [ � rV\Ã�irnx®] m�e rV\"wÃ� e � m ] � �i[ g { h {nrV} h tÂ�hkm�e��&c3g \�] j r mih {V]Ã~ ��[ _ l rV��["\�x c3g ]?�i]z]?\ h \ m ] g r _ mBhkc \"��r �Zc \ j _ c3�Zd£c \�]?\ m ��� x c3g ]�¢�r �Zd ts]nu _ c {3] g9m_ l rV\�\"]?tk� mil r m ]�¢ h � m;c \�t e � l ]z\ _ cV�­d�c \"]z\ m �;r g ] _ c3� } h \"]zw ��� o hs�Zd t e _ cV�­d�c � h \ j r�� e � m ] � cVg\"] m � c3g��yc [ m�c x hÂm � _ c3�Zd�c \"]?\ m � d"g�c { h w"]?�¯\ c _ ] g9m r h \ m�e � l r m ]�{3] g¯mBl r m�mil ] g ]?��["t mih \ j � l"c tk]¶� h tst� c3gi� rV�;w�]?� hkg ]zw1u�]z{V]?\ h x mil ] _ c3�Zd£c \�]?\ m � mil ] � �i]ztk{V]?�F��]?] � mBc }£] l r�{3] d"g�c3d ] g t e3�«º \�] c x mBl ]�Zc � m¯hs�Zd�c3g�m rV\ m _ l rVtstk]?\ j ]?� _ c \§x gic \ mBh \ j ["� h � mBc }�]DrV}"tk] mic w"] gih {3] mBl ]D] � ] g�j ]?\ m�d"gic3d ] g9mBh ]?� c xr­� e � m ] � h \ mBl ];t|r gij ]�x gicV� mil ] d�gic3d ] g9mBh ]z� c x hkm � _ cV�­d�c \"]z\ m ��rV\�w«x gic3��mil ] � rV\"\�] g#h \µ� l�h _ lmBl ] e r g ] h \ m ] j3g r m ]?w �� l ] g ] h �FrV\ hk�­d�c3g�m rV\ m } c w e c xI� cVgi� w"]z{ cVm ]zw mic w"] d ]z\"w�rV}"tk] � e � m ] � �µ~ ]z� d ] _ h rVtkt e²h \ � [P�

gicVd ] � rV\"w mBc©l�hsj3l ��rV�i��[ g rn\ _ ]Ã� e � m ] � ��~ ]z� d ] _ h rVtkt e�h \ mil ]y¬ � o �¦��� � l ]?�i]µr g ] g ]?rVtst e rn� d ] _ m � c xmBl ]D�ir � ] mil"h \ j"� ��� e � m ] � � l"c ["tswµ}£] _ r d rV}"tk] c x¾�ir mBh ��x ePh \ jZhÂm � g ]� '[ hsg ] � ]?\ m �zuRw"] d ]?\"w"rV}"t e rn\"w� hkmil r d"d"gicVd"gih r m ]yrV���i[ g rV\ _ ]VuN� l r m ]z{V] gZmBl"c ��] g ]� '[ hkg ] � ]z\ m ��r g ] � o§[ g { h {nrV} h t hkm�e h �ZrV\ c {3] g r g �_ l"h \ jÃg ]� P[ hsg ] � ]z\ m�mBl r m�hs�Zd t h ]?�¯�i] _ [ gihÂm�e u g ]?t h rV} h t hkm�e u�rVw"]� '[�r m ] d ] g x cVgi� rV\ _ ]nu�rV\"w � rV\ e«cnmBl ] g�i[�} g ]� P[ hsg ] � ]z\ m � �

� �����N( (*� ,�-��¾�"�N,��

� l ]�x c tst c � h \ jyg ] _ c3�Z� ]z\"w�r mihsc \"��r g ] c3g w"] g ]?w gic [ j3l t e r _?_ cVg w h \ j�micªl"c � mBl ] e r d"d ]?r g;h \ mBl ]w"]�{3]?t c3d"� ]?\ m rV\"w c3d ] g r mBhkc \�rVt _ e _ tk]?� � � l ] hsg�g ]?tsr mBh {3] hs�Zd�c3g�m rV\ _ ] h � _ c \"� h w"] g ]?w r m�mBl ]Z]z\"w c xmBl ]D]z\'[ � ] g r mihsc \ �

� �¾¿ ] � [�� m ]?� m rV}�t h � l©j ]?\�] gih _ �­h �i� hsc \ �Zc w"]?tk� mBl r m _ rn\�}�] g ]?rVw h t eym r h t c3g ]?w mic � d ] _ h ± _ � e ��m ] � �?u�rV\"wªw"]�{3]zt c3d©d"g�c _ ]?���i]?��� l ] g ]z} eªmBl"c �i] �Zc w�]?ts� _ rn\ª}£];["�i]zw h \ª]�{Vrnts[�r mih \ j�mBl ]�rVw"]�� '[�r _ eÃc x g ]� '[ hsg ] � ]?\ m � �

^ �¾¿ ] � ["� m ]?� m rV}"t h � l x®["\"w�r � ]?\ m rVt g ]� '[ hkg ] � ]?\ m �¾x c3g �i[ g { h {nrV} h t hkm�e rV\�w hkm � ��["} m ]z\"w"]zw d�gic3d ] g �mih ]z� mil r m _ rV\ }�]¯w hsg ] _ m t e r d�d t h ]?w mBc � e � m ] � w"]�{3]zt c3d"� ]?\ m �IrV\"w d"gic _ [ g ] � ]?\ m �zu���[ _ h ]z\ m t ew�] m r h ts]zwÃ}"[ m \ cVm&c {V] g t e _ c \�� mBg r h \ h \ j"�

W �¾¿ ] � ["� m w"]z±�\�]¯x r �Zh t h ]z� c x£� e � m ] � rV\�wZ\�] m � c3gi� r g _ l"hkm ] _ m [ g ]?� mBl r m r g ] h \ l ] g ]z\ m t e;gic }�["� m urn\"wyw"] �Zc \"� mBg r m ] mBl ] hk�­d tk] � ]?\ m rn} h t hkm�e�c x mBl"c �i]Dr g _ l�hkm ] _ m [ g ]z� �

� �¾¿ ] � ["� m w�]z{3]zt c3d \"]z��\"] m � c3gi� rV\�w�w h � migih }�[ m ]zw�� e � m ] � d�gicVmic _ c ts��r d�d"gic3d�gih r m ] x c3g�mBl ]w�]z{3]zt c3d�� ]z\ m¯c x l"hkj3l t e �i[ g { h {nrV}"tk]Vu���] _ [ g ]Vu�rV\�w g ]?t h rV}"tk] h \§x c3gi� r mBhkc \ h \�x g rn� mBg [ _ m [ g ]z� �

� �¾¿ ] � ["� m w"]?� hsj \;rV\"w hs�Zd ts] � ]z\ m)c3d ]?\P��� e � m ] � r g _ l"hkm ] _ m [ g rVt _ c3�Zd£c \�]?\ m � mBl r m r g ]5]z�i�i]z\ mBh rntx cVg�gic }"[�� m r g _ l�hkm ] _ m [ g ]z��}"[ m \ cnm�e ] m�g ]?rVw h t e r�{nr h t|rV}"tk] h \ mil ] � r g�� ] mBd tsr _ ]nu�� l�h _ l � l ]?\_ c3�Zd£c ��]?w mBc3j ] mBl ] g _ rV\F�ir mBh ��x e � migic \ j�g ]� P[ hsg ] � ]z\ m � x cVg ��[ g { h {Vrn} h t hkm�e rV\�w h \ m ] gicVd ] g rV} h t hÂm�e3�

� �¾¿ ] � ["� m ]?� m rV}"t h � l r;t h } g r g9e�c x�w"] �­c \"� mig rV}"t e � c ["\�w d"gic _ ]zw"[ g ]z� mBl r m ]?\"rV}"ts] mBg ["� m � c3g�milfe� e � m ] � � mic }£]�}"[ h t m1c [ m�c x§ts]z�i� mig ["� m � c3g9mBlfe _ cV�­d�c \"]z\ m � � � l"h � h � mBl ] _ c \ _ ] d�m)c x ��� ��� ������� ���� � � ���� �������� � l�h _ l �N]D]�¢ d t c3g ] h \ mil"h � g ] d�c3g�m?�

� � �

Page 15: Practical Architectures for Survivable Systems and Networks (Phase

  �¾¿ ] � ["� m ]z� m rn}"t h � l rV\"w _ c \"� h � m ]?\ m t e ["�i]¯� c ["\"w _ g�ePd�mic3j3g r d"l"h _ h \§x g rV� mBg [ _ m [ g ]?� x c3g rV[ mil ]?\P�mih _ r mBhkc \1u _ ] g9mBh ± _ r m ]DrV[ mBl�c3gihÂmBh ]z�?u�rn\"w _ c \�±"w"]?\ mBh rVt hÂm�e3�

� �¾¿ ] � ["� m ±�\"wµ�½r e � mic ]z\ _ c [ g r j ] _ cV�­� ] g _ h rnt1� e � m ] � w"]z{V]?t c3d ] g � mBcZh \ _ g ]�rn�i] mil ]D�i[ g { h {f�rn} h t hkm�e uP�i] _ [ g�hkm�e uRrV\"w g ]zt h rn} h t hkm�e�c x mBl ] hsg � m rn\"w�r g w d"g�c w�[ _ m �?u h \ _ ts[�w h \ j ]?\ _ c [ g r j3h \ jFmil ] �mic ] � } g r _ ] �Zc3g ] jVc§c w g ]z�i]�r g _ l rn\"w�w�]z{3]zt c3d�� ]z\ m¯g ]?�i[�t m � �

� �¾¿ ] � [�� m _ c \"� h w"] g u�rV�&rV\yrnt m ] g \�r mBh {V] mic�d"gic3d�gih ] m r g9e _ t c ��]?w§�¼� c [ g _ ]�� c x m �Nr g ]nu mBl ]�w�]z{3]zt c3d �� ]?\ m rV\"w [��i] c x�� c [ g _ ]���r�{Vr h t|rn}"ts]&� c x m �½r g ]�rV\�w \ c \ d�gic3d"g�h ] m r g9e­h \ m ] g x r _ ]z� � ��t mBl�c [ j3lZmBl"h �r d"d"gic r _ l w c ]?��\ cVm \�] _ ]z�i�ir gih t e ts]�rnw mBc �i[ g { h {nrV}"ts]D� e � m ] � �¶rVtkt�} e�hkm �i]ztkxu hkm�l rV�#]z\ c3g��­c [��d�cVm ]?\ mBh rVt£� l ]z\ _ c3� } h \"]?wÃ� hkmil�cnmBl ] g½m ] _ l \ h '["]z� �

�TX �¾¿ ] � ["� m�d"g�c { h w"]Zx cVgD� ] _ l rV\ h � � �¶x c3g�mBg ["� m � c3g9mBlfe w h � migih }"[ mBhkc \ c x mig ["� m � cVg�mBlfe _ c w"] �h \ _ tk["w h \ jFgic }"["� m¯�Zc } h ts] _ c w"] �

�3� �¾¿ ] � [�� m&g ]�±�\"]¶rV\�w � r � ] d"g r _ mBh _ rVt mBl ] c \ j3c3h \ j p �¶¨ ]z» c3g�m �½x c3g½�Zc \ hkmic3gih \ j u'rV\"rVt e �?h \ j urn\"w g ]?� d£c \�w h \ j²mBc � e � m ] � rV\"w \"] m � c3g�� rV\ c3� rVt h ]?�zu5rn\"w j ]z\"] g rVt h�� ] mil ] � x g�c3� � ] g ]zt eh \ mBg [�� hsc \§��w"] m ] _ mBhkc \ � e � m ] � �zu�� cFmBl r m½mBl ] e rnw"w g ]z�i�¯rF} g�c rVw g rn\ j ] c x)��[ g { h {nrV} h t hÂm�e � g ]zt|r m ]?wmil"g ]?r m �zu h \ _ tk["w h \ j©g ]zt h rn} h t hkm�e²d"g�c }"ts] � �zu�x rn["t m � mBc ts] g rV\ _ ] _ c {3] g r j ]µx r h ts[ g ]?�zu5rn\"w _ t|rn�i� h _ rVt\�] m � c3gi�Ã� rV\�r j ] � ]?\ m��

�¸^ �¾¿ ] � ["� m }�]²rV}"ts] mBc w"]z{V]?t c3d � e � m ] � � mil r m r g ] �Zc3g ]ª]?rV� h t e _ c \§± j [ g ]?w rV\"w � rn\�r j ]zw� hÂmBl"c [ m&d t|r _ h \ j ]�¢ _ ]z�i� h {3]�}"[ g w�]?\"� c \y� e � m ] � rVw �Zh \ h � mig r mic3g � �

�TW �¾¿ ] � ["� m�d [ g ��["] g ]�rVt h � mih _ g ]?��]�r g _ l rV\"w w"]z{V]?t c3d"� ]?\ m«g ]?tsr mBh \ j mBc d"g r _ mBh _ rVt�� e � m ] � h �9���["]?�¶��[ _ l rV� _ c3�Zd£c �irV} h t hkm�e u � r h \ m r h \�rn} h t hkm�e uR]�{ c tÂ{Vrn} h t hkm�e u h \ m ] gic3d ] g rV} h t hkm�eymil r m r g ]�rVts� c� mBg�c \ j t e }�rV��]?w mBl ] c3g ] mBh _ rVtkt e3�

��� �¾¿ ] � ["� m ±"\"w �Nr e � mBc w h ���i] �­h \�r m ] mil ] _ c \ _ ] d�m � c x mBl�h � g ] d£c3g9m � h w"]zt e u h \ _ tk["w h \ jµh \�³�[§�]z\ _ h \ j�mBl ]¶]zw"[ _ r mBhsc \ d�gic _ ]?���i]z��rV\"w hs�Zd"g�c {V]?w mBg r h \ h \ j"�

q m h �¾rntk�Nr e � w�]?� hkg rV}�ts] mic#h \"w h _ r m ] g ]zt|r mih {V] d"g�hsc3g�hkmBh ]?� h \D� l"h _ l ��[ _ l�g ] _ c3�Z� ]?\"w�r mBhsc \"� \�]?]?w mic}�]�rnw"w g ]z�i��]?w1u�rn\"w mil ] hkg g ]?tsr mBh {3]Iw h� _ ["t m�e3� ¬¯\�x c3g�m ["\�r m ]?t e u'�i[ g { h {nrV} h t hkm�e u3�i] _ [ g�hkm�e u�rV\�w g ]zt h rV} h t �hkm�e r g ]I�5]�r � ��t h \ �;d"l ]?\ c3� ]z\�r mBl r m _ rV\�}�] _ c3�Zd"gicV�­h �i]?w h \ � rV\ e w h »�] g ]?\ m �Nr e � � � l ["�zu�rntst mBl ]rV} c {3] g ] _ c3�Z� ]z\"w�r mihsc \"� _ rV\ l rT{V] _ c \"� h w"] g rV}"tk] d r e3c »£� h \ ]�» cVg�m � mic w"]�{3]zt c3d �i[ g { h {nrV}"ts]�� e ��m ] � �zu3x c3g�� rV\ e w h »�] g ]?\ m g ]�rV� c \"� � }£] _ rV[��i] c x mBl ] l"c t h � mBh _ \�r m [ g ] c x mil ]Iw"]?� hsg ]?w g ]� '[ hkg ] � ]z\ m �rV\"w mBl ] h \ l ] g ]?\ m _ cV�­d tk]�¢ hkm�e�c x mBl ] hsgIg ]?rVt h�� r mihsc \ �q mFh �;w h� _ ["t m�micªd"h \ d£c3h \ m�mil ] g ] _ c3�Z� ]?\"w�r mBhsc \"� mil r m��ZhsjVl'm�d"g�c { h w"] mil ] j3g ]�r m ]?� mFd r e3c »£�� d"g ] _ h �i]?t e }�] _ rn["�i] c x mil ]Ã�N]?r � ��t h \ � d"l ]?\ c3� ]?\"r �b´ ]z� h w"]?�zu½�i]?r g _ l"h \ j x c3g ]�rV� e rV\"���5] g � h �

r _ c3�Z�­c \ x r h t h \ j u&]?� d ] _ h rntst ebh \ _ c3�Zd ts]�¢�� hÂm [�r mBhsc \"� h \�� l"h _ l mBl ] g ] r g ]�\ c ]?rV� e rV\����5] g � �( c �5]z{V] g u h \ j ]?\"] g rVt mBl ] j3g ]?r m ]z� m t c \ j � m ] g�� }£]z\"]z± m ���i]z] � mic r _?_ g ["]5x gic3� [ d �vx gic \ m ]�» c3g9m �zu mBl r mh �zu g ]?tsr mBh \ j½mBc ]?� m rV}"t h � l"h \ j � c ["\"w g ]� '[ hkg ] � ]z\ m �?un� e � m ] � w"]?� hsj \"�zu3rV\�w;r g _ l"hkm ] _ m [ g ]?�?u g r mil ] g�mBl rV\x c _ ["� h \ j¯c \D� c x m �Nr g ]�w"]�{3]?t c3d"� ]?\ m u c3d ] g r mBhsc \"�?u mBc3d�h _ rnt d"g ]�{3]z\ mih {V] � ]?rV�i[ g ]?�zu3rV\�w � r h \ m ]?\�rV\ _ ] �� l r mµh � � l'e �5] l r�{3] _ l"c �i]z\ mil ] c3g w"] gÃc x g ] _ c3�­� ]?\�w�r mBhkc \"�Ãrn��rn} c {3]nu hs�Zd t h _ hÂm t e d t|r _ h \ j] �Zd"l rn� h � c \ mBl ] hkm ] � � h \ mBl r m c3g w"] g?� � ]z{3] g�mil ]?tk]?�i�zu mil ] g ]ª� c [�tswb}�] � r ��c3g }�]?\�]z± m � x gic3�rVt �­c � m rVtkt mBl ] hÂm ] � �&rV} c {3] �q�\ d r g9mBh _ ["t|r g u mBl ]©]z� m rV}"t h � l"� ]?\ mÃc x �Zh ��� hsc \ �­c w"]zts�²~� � rV\"w x®["\�w�r � ]?\ m rVt g ]� '[ hkg ] � ]z\ m �

~v^ �;�­hkj3lfm�l r�{3] mBl ] j3g ]�r m ]?� m }�]?\"]�± m � c x#rVtstKu�}£] _ rV[��i] hkm _ c ["tsw d"g�c { h w"] mBl ]y}�rV� h ��x c3g � e � m ] �

� � � �

Page 16: Practical Architectures for Survivable Systems and Networks (Phase

w"]�{3]?t c3d"� ]?\ m � rn\"w d"gic _ [ g ] � ]?\ m � c xR� e � m ] � � � ( c �N]�{3] g u d rV� m ]�¢ d ] gih ]?\ _ ]½� hkmBl�mBl ]I¨ c ¨ � g ["� m ]?waNc3�Zd [ m ] g o§] _ [ gihÂm�e�� {Vrnts[�r mihsc \ aNg�hkm ] gih rµrn\"w � e � m ] � d"gic _ [ g ] � ]?\ m ���i[ jVj ]?� m � mBl r m¶mil"h � h �¶\ cnmrV\©]?rV� e«d r mBl u�rV\"w mBl r m ]z{V]?\ h x��5] l rVw²r ��[ d ] g }��i] m�c x g ]� P[ hsg ] � ]z\ m �?u mil ] e«�­hkj3lfm }�]Ft|r gij ]zt ehsj \ c3g ]zw �

o migic \ j ] g r g _ l"hkm ] _ m [ g ]?�?u _ c3�­d�c \"]z\ m �?u d"g�cVmBc _ c ts�?u rV\"w _ g9ePd�mBc3jVg r d"l�h _ h \§x g rV� mBg [ _ m [ g ]?�Ã~KW�u��"u�§u&��u¯  � r g ]ªrVtkt d�cVm ]?\ mBh rVtst e hs�Zd£cVg�m rn\ mZmBc�mBl ]«w"]z{V]?t cVd"� ]z\ mÃd"gic _ ]z�i� � q�w"]�rVtkt e u mBl ] e \�]?]?w mic}�] �ZcVmBh {Vr m ]?w�} e � mBg�c \ j�g ]� '[ hkg ] � ]z\ m � � q�\ mBl ] rV}"��]?\ _ ] c xI��[ _ l ]�¢ d t h _ hkmDg ]� P[ hsg ] � ]z\ m � h \ mBl ]d rV� m u§� e � m ] � � l r�{3]�w�]z{3]zt c3d ]?w r _?_ c3g w h \ j�mic r���t c � �Zhsj3g r mBhkc \ d r mil�mBl r mNh �5w g�h {V]?\ d"g�hs� r gih t e } ed ] g _ ] h {3]?w � r g�� ] m _ c \"� h w"] g r mBhkc \"�zu'� l�h _ l�l rT{V]#\ cnm _ c \f{3] g�j ]?w c \Z� l r mNh �5\"]z]?w"]zw � q�\ _ ]?\ mBh { h��?h \ j� r h \§�¼� mig ]�r � w"]�{3]zt c3d ] g �«~ � � rV\�w d"g�c3�ZcVmBhkc \ c x�� c [ g _ ]��r�{nr h t|rV}"tk]�� c x m �½r g ]µrV\"w c3d ]?\ � e � m ] � �~K�§uk�TX � r g ]�} cVmBl { hkm rVtvu d r g�mih _ ["t|r g t eZh x mBl ]Dtsr mim ] g½h \"� d�hsg ]z� j3g ]?r m ] g rVw�{nrV\ _ ] � ]?\ m } eÃmil ]�x c3gi� ] gz�p&]�rVt � mBhk� ]FrV\�rVt e � h � c xN� e � m ] � �­c \ hkmBcVgih \ j rV\"w g r d"h w g ]?� d£c \��i]²~�3� � r g ]Z]?���i]z\ mih rVtKu }�[ m;d�gih �

� r gih t e rV�DrµtsrV� m�g ]?� c3g�mDh \ mil ] d"g ]z�i]z\ _ ] c x5{P["tk\"] g rV}"tk]Z� e � m ] � � � q�w�]�rVtkt e u jVg ]�r m ] g ] �­d"l rV� h � c \[ d �vx gic \ m�g ]� '[ hsg ] � ]?\ m �NrV\"w­r g _ l"hÂm ] _ m [ g ]?��� c ["tsw­w hs�Zh \ h � lFmil ]�\�]?]?wZx c3g g ]?rVtÂ� mBhs� ]IrV\"rVt e � h � � r mts]?rV� m � hkmBlyg ]?� d ] _ m&mBc�c [ m � h w"] g r mim r _ � � � ( c �N]�{3] g u mBl"h � h �I\ cnm t hk� ]?t e­mic�l r d"d ]?\Ãx c3g r�t c \ j;mihs� ] �´ [ h tsw h \ j � e � m ] � � mBl r m r g ] �Zc3g ]I]?rV� h t e rnw �­h \ h � m ] g ]?w�rn\"w­� hs�Zd t h x ePh \ j¯mBl ] gic ts] c x£� e � m ] � rVw§�

�Zh \ h � mBg r mBhkc \�~�¸^ � � c ["tkw ePh ]ztsw j3g ]�r m �irT{ h \ j � h \¶t|rn} c3g rV\"w _ c � m uVrV�1�N]ztst'rV� �Zh \ hk�­h��?h \ j ] � ] gij ]z\ _ eg ] � ]zw h r mBhsc \ ~ ]z� d ] _ h rVtst eªh \ _ c3� } h \�r mihsc \ª� hÂmBl²�Zc3g ] h \ m ]?tkt hkj ]?\ m�g ]�rVt � mBhk� ]�rV\�rnt e � h � ��� ( c �N]�{3] g uc [ m � c [ g _ h \ j4c x�rVw �Zh \ h � mig r mic3g � h ��r l"hsjVl t e4gih � � x®["t d�gic3d�c � hÂmBhkc \ � ~ p¯] _ ]z\ m t e u½� e � m ] � rVw �Zh \ h �9�mBg r mBcVg � h \ o§p¯q � � aNc3�­d [ m ] g o _ h ]?\ _ ] ��rV} c3g r mBc3g9e _ c3�­d t|r h \"]?w mic mBl ] hsg _ c ["\ m ] g�d r g9m �µr m ¡ c3g�m(�["r _ l [ _ r g ]zt|r mih \ j«mic r l"c � m � hÂmBl"h \ mBl ] ¡ c3g9m (�["r _ l [ _ r²w c3� r h \ mBl r m �NrV� h �i�i[ h \ j©g ] d ]�r m ]?ww c3� r h \ \�r � ]Z�i] g { h _ ]²~K¨ � o �¶g ]� '["]z� m � mic r � r _ l"h \"]�� hkmBl�h \ c [ gFa o§� \"] m � cVgi�²mBl r m�h ��\ cVm r\�r � ]&�i] g {3] g?� � l ] l [ � rV\ g ]z� d�c \"��]��NrV� h \­]�»�] _ m u'�5]?tstKu hkm h �5rnx m ] g W h \ mil ]�rnx m ] g \ cPc \ c \ ¡ gih w�r e urV\"w c [ g rVw �­h \�]z» c3g9m �Ir g ] c [ m � c [ g _ ]?w mBc r _ c \ mBg r _ mic3g � l"c �i]�r�{nr h tsrV} h t hkm�e;h �5["\ _ ] g�m r h \ � o c3gig9e3�¦�¡ [ g�mil ] g��­cVg ]Vu�t c \ j � m ] gi� g ]?��]�r g _ l rV\"wµw"]�{3]?t c3d"� ]?\ m�h �i��["]?� � ["� m \ cVm }£] hsj \ c3g ]zw ~9�TW ��� o d ]��

_ h ± _ w hsg ] _ mBhsc \"�Nx c3g p �¶¨ r g ]¶w h � _ ["���i]?w h \�o§] _ mBhkc \µ� � ^ c x mBl�h � g ] d£cVg�m��¿�l ]z\«r m�m ] �­d�mih \ j�mBc _ c \§x gic \ m r _ c3�Zd tk]�¢Ã� e � m ] � d"gic }"ts] � u _ c \"� h w"] g rV}�ts]�}�]?\"]�± m _ rV\ g ]z�i["t m

x gicV� _ c \"� h w"] gih \ j mBl ]«� hÂm [�r mBhsc \ h \ mBl ]�t|r g�j ]4~ mBcVd ��w c �&\ � u g r mil ] gZmBl rn\ r mim ] �Zd�mBh \ j mic4d r m _ lmBcVj ] mil ] g r }"["\ _ l c x�]�¢ h � mBh \ j � c ["tsw§�¼}£]©� c ts[ mBhsc \"�²~ } cVm�mBc3� ��[ d���� � l ]�} cVm�mBc3� ��[ d r d"d"gic r _ lm�ePd"h _ rVtst e�� r � ]z� [�\ g ]?rVt h � mBh _ rV���i[ �Zd�mBhkc \"�)rV} c [ m�mBl ] h \"w"] d ]?\�w"]?\ _ ] c x§�i[�} d"gic }"ts] � � � � l ] l"c t h � mih _r d"d�gic r _ lym r � ]?\ l ] g ]Dr mim ] �Zd�m � mBc rVw"w g ]?��� mil ]�� l"c tk]�� e � m ] � u£rn\"w mil ]?\��i]z]¶� l r m _ rV\�}£]�w c \"]mBc¶d r g�mBhÂmBhkc \ mBl ] d�gic }"tk] � � � l"h tk]IrVtk� c w"]�rnt h \ j � hkmBl�mil ] h \ m ] g r _ mBhsc \"��r �Zc \ j�mBl ] _ c3�Zd£c \"]?\ m � � q�\� cV� ] _ rn�i]?�zu hÂm h ��rVw�{nrV\ m r j ] c ["� mBc _ c \"� h w"] g rD� c3� ]�� l r m��Zc3g ] j ]z\"] g rVt d"g�c }"ts] � mBcDj r h \ h \"� hsj3lfm �mBl r m _ rV\"\ cVm }�]Z�i]?]z\4x gicV� mBl ] �Zc3g ]�� d ] _ h ± _ d"g�c }"ts] � ~ ]z� d ] _ h rVtkt e � l ]?\ mil ]­� d ] _ h ± _ d�gic }"tk] �h �D\ cVm �5]?tst�["\"w�] g � mBcPc w ���y¿ ]­}£]zt h ]�{3] mBl r m ��[ _ l rV\ r d�d"gic r _ l4h ��rVw�{nrV\ m r j ] c ["� h \4w"]�{3]?t c3d"h \ j_ cV�­d tk]�¢ � e � m ] � � �q m5h � _ tk]�r g mBl r m � e � m ] � r mBh _ ["�i] c x1� mBg�c \ j rn[ mBl ]z\ mBh _ r mBhkc \«~ h \ _ ts[�w h \ j r�{ cVh w�rV\ _ ] c x�±�¢§]?w d rV�i��

� c3g w"� � _ c ["tkw l r�{3] rV\�]?\ cVgi�Zc ["� hk�­d r _ m rVtkt#} e hÂm �i]ztkx c \�� e � m ] � h \ m ] j3gihÂm�e3� ¡ hsg ]��½rntsts� mBl r mr g ]ª�i] _ [ g ] rn\"w d"gicVd ] g t e rVw �­h \ h � m ] g ]?w+� c ["tkw l ]?t d1� ( hkj3l t e ��[ g { h {Vrn}"ts]ª��] g {3] g �Ã� c [�tsw }�]©r_ c \"� h w"] g rV}"ts]Ã}�]?\�]z± m?� � c3g ] d"g ] _ h �i] g ]� '[ hsg ] � ]?\ m ��� c ["tkw l rT{V]«r � r ��c3gFh \�³�["]z\ _ ] c \ � e � m ] �d"g�c _ [ g ] � ]z\ m �

h x mil"c �i] g ]� P[ hsg ] � ]z\ m �5�5] g ]#�ir mBh ��±�]zw � o§] g�hsc [�� _ c \"� h w"] g r mBhkc \ c x�rV\ cVd ]z\§��w"]z� hkj \d�c t h _ eyc x�]�¢ m ]?\"� h {3]�]?r g t e�g ]z{ h ]�� rn\"w mBl ];["�i] c x � c [ g _ ]���r�{Vr h t|rn}"ts]D� c x m �Nr g ]F� l ] g ]�r d"d"g�c3d"gih r m ]� r e h \ mil ]Ãt c \ j©g ["\ }�]Ã]?���i]z\ mih rVt mic©c {3] g _ c3� ] mBl ]Ãt hs�Zhkm r mBhkc \"� c x d"g�c3d"gih ] m r g�e _ t c �i]zw§��� c [ g _ ]� e � m ] � � mBl r m _ rV\"\ cVm x®["tk±"tst mBl ]²w"]z� hsg ]?w g ]� '[ hsg ] � ]?\ m � � �#t m ] g \�r mih {3]²r g _ l"hÂm ] _ m [ g ]?� h \ _ ts[�w h \ j

� � �

Page 17: Practical Architectures for Survivable Systems and Networks (Phase

r���] _ [ g ] �­c } h ts]�� _ c w"] d r g rnw hsj3� l r�{3] _ c \"� h w"] g rV}"tk] d�gic3�Zh ��]Vu d r g�mih _ ["t|r g t e�h \ _ c \�\"] _ mBhsc \ � hkmilmBl�h \§� _ t h ]?\ m � e � m ] � �ZrV\"w l"hkj3l t e�mBg ["� m � c3g9mBlfe �i] g {3] g � ��´ [ m�mil ]y} cnmimBcV� t h \"] l ] g ] h � mil r m�mBl ]}�rV� h _�_ c3�­d [ m ] g � _ c3�Z� ["\ h _ r mihsc \ h \�x g rn� mBg [ _ m [ g ] h �½x®["\"w�r � ]?\ m rVtst e�h \�rVw"]� P["r m ] mBc w�r e3�

�����£��¼���)���"����� � ,�-��'( ����)( �),N���¾���N,

� l ]�["�i] c x � mBg [ _ m [ g ] h � d r g9mBh _ ["t|r g t e�hs�Zd£cVg�m rn\ m&h \yw"]?� hsj \ h \ j u hk�­d tk] � ]?\ mBh \ j u�rn\"w � r h \ m r h \ h \ j� e � m ] � �IrV\�w�\"] m � c3g�� � � � l ] _ c3� } h \�r mBhkc \ c x�r g _ l"hkm ] _ m [ g rVt d"gih \ _ hkd ts]z�5rn\"w mBl ]�["��] c x j3c§c wZ� c x m ��Nr g ]�]?\ j3h \"]?] gih \ j rn\"w«� e � m ] � ]z\ j3h \"]?] gih \ j­d"g r _ mih _ ] _ rV\«}�]�]�¢ mBg ] � ]zt e ]�»�] _ mBh {3] � q�\ d r g9mBh _ ["t|r g uhkm�h ��{ hÂm rVt mic rVw"w g ]?�i� mBl ]�x®[�tst g rV\ j ] c x&��[ g { h {nrV} h t hÂm�e � g ]zts]�{Vrn\ m�g ]� '[ hsg ] � ]?\ m �;x g�c3�/mBl ] c [ m ��] m��hkm�h � m�ePd"h _ rVtst e {3] g9e w h� _ ["t m�micª� r � ] g ] mBg�c ± m �Ft|r m ] gz� � l ]Ã\ cVmBhkc \ c x j ]?\"] g rVt h�� ]zw w"] d ]z\"w"]?\ _ ]_ c \"� h w"] g ]?w h \ mBl"h � g ] d£cVg�m½d ] g��­hÂm �5["� mBc rT{ c3h w�\"]?]zw h \ jFmicVm rnt£w"] d ]z\"w"]z\ _ ] c \ mil ] _ c3gig ] _ m \"]?��� c x_ ] g�m r h \ cVmil ] g _ c3�­d�c \"]z\ m � � � rV\ eFc x�� l"h _ lZl rT{V]�[�\ � \ c �&\ mig ["� m � c3g9mBl"h \"]?���?u c3g r g ] h \ l ] g ]z\ m t e�i[�� d ] _ m?� � l"h � h � mBl ]F\ cVmBhkc \ c x c } m r h \ h \ j­mig ["� m � c3g9mBl"h \"]?����w"]?� d"hkm ] mil ] g ]zt|r mih {V]�["\ mig ["� m � c3g9mBl"h �\"]z�i� c x _ ] g9m r h \ _ c3�­d�c \"]z\ m � � � l"h � _ c \ _ ] d�m­h � h \ _ g ]�rV� h \ j t e hk�­d�c3g9m rV\ m�h \ l�hsj3l t e w h � migih }"[ m ]zw_ cV�­d [ mBh \ j ]?\f{ hsg�c \ � ]?\ m � � � g ]�{3]z\ mih \ j c3g �i] gihkc ["�it e l"h \"w�] gih \ j w�]?\ h rVtÂ� c x|����] g { h _ ]�r mim r _ � � h �­rd r g9mBh _ ["tsr g t e�hs�Zd£c3g9m rV\ m r g _ l"hÂm ] _ m [ g rVt h �i��["] � � l ] �Zc } h ts]�� _ c w"] d r g rnw hsj3�*c »£] g � � rn\ e�d£cnm ]?\ mih rVtrVw�{nrV\ m r j ]?� h \��i[ _ l ]?\f{ hsg�c \ � ]?\ m �zu¾}"[ mDhÂm rnts� cµg ]� '[ hsg ]?�D� c3� ]�w g r � r mih _ hs�Zd"g�c {V] � ]?\ m � h \ mBl ]�i] _ [ g�hkm�e u g ]?t h rV} h t hÂm�e uPrV\"w gic }"["� m \"]?��� c x _ ] g�m r h \ _ g�hkmih _ rnt _ cV�­d�c \"]z\ m � �

� �N,����9���"�N,��

q m¶h ��r w h _ [�t m _ c [ g ��] mBl r m �N] � ["� m x c tst c � � q m¶h ��]z{ h w"]?\ m t e rÃ\"]�{3] g ��]z\"w h \ j _ c [ g �i]Vu�x c3g rÃ{nr��gih ] m�eyc x g ]?rV� c \�� � �#� mBl ] g ]� '[ hsg ] � ]?\ m � _ c \ mih \'["] mBc }£]D}£] mim ] g ["\"w"] g � mic§c w1u �Zc3g ] h �&w"] � rn\"w"]?w ��#� m ] _ l \ h _ rVt hs�Zd"gic {V] � ]?\ m ��r g ] h \ migic w"[ _ ]zw1uR\"]z�0{P["tk\"] g rV} h t hkmih ]z�Ir g ] m�ePd"h _ rVtst e h \ migic w"[ _ ]?w � ���m ] _ l \ c t c3jVe _ c \ mBh \P[�]?� mBc�c »�] g \"]z��x®[�\ _ mihsc \�rnt c3d"d�c3g�m ["\ hÂmBh ]z�?u5rV\"w�rV��� e � m ] � � m ]?\"w mBc�c3d ] g �r m ] _ t c ��] g�mBcµmBl ] hsg�m ] _ l \ c t c3j3h _ rVt�t hk�­hÂm �zu mBl ]�{P["ts\�] g rn} h t hkmBh ]?�zu mBl"g ]�r m �?u rn\"w g�h � � �;r g ] h \ _ g ]�rV��]?wr _z_ c3g w h \ j t e u g ]� P[ hsgih \ j�� [ _ lZjVg ]�r m ] g _ r g ] � º�d ] g r mBhsc \�rVtPrV\"w�rVw �­h \ h � mBg r mBh {V] _ l rVtstk]?\ j ]z��r g ] _ c \P�mBh \'[�rVtst eµh \ _ g ]�rn� h \ j"� ����� e � m ] � � _ c \ mBh \'["] mBcyj3g�c � h \ _ c3�Zd ts]�¢ hkm�e rV\"w²� h�� ]Vu mil ] gih � � ���i]z] � micj3g�c � r _?_ c3g w h \ j t e3� ���;r g ]?��["t m u¾]�{3] g�j3g ]?r m ] g�g ]?t h rV\ _ ] h � d t|r _ ]?w c \ mil ] cV� \ h � _ h ]?\ _ ]ZrV\"w c3� �\ hkd£cVm ]?\ _ ] c x�� e � m ] � rVw �Zh \ h � mBg r mBcVg � � ��ts� c u c [ g rVw�{3] g �ir gih ]?� r g ]½}£] _ c3�Zh \ j�� [ _ l��Zc3g ]Nr j3h tk]Nrn\"wr g ] _ r d rV}"tk] c x1}�] _ c3�­h \ j¶� [ _ l­�­c3g ]¯r j3j3g ]?�i� h {V] � �#�5r _ c \"��]� '["]?\ _ ]Vu � [ _ l�jVg ]�r m ] g w h � _ hkd t h \"] h �g ]� '[ hsg ]?w mic r _ l�h ]z{V] mil ]�\�] _ ]z�i�ir g�e­j3c rVtk� � � l"h � g ] d£c3g9m r mim ] �­d§m � mBc _ l r g r _ m ] gih�� ]�� l r mNh � \"]?]zw"]?wh \ m ] gi� � c x h \ _ g ]?rV�i]zwªr��½r g ]?\�]?�i�#rV\"wy\"]�� r d"d"g�c r _ l ]z�¯x cVg½mBl ]�x®[ m [ g ] �

� �

Page 18: Practical Architectures for Survivable Systems and Networks (Phase

� � �

Page 19: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

��� � ��� � � � � ���

������� � ��� � � � ��������� ���� � � � ��� � � � ������ ��� � � � � �� � � ��� ��! � � � � � � �"#�%$ � �& � � � � � � � ��� � � ' � � � � ��� ��� ��� � � � � � � � � � ���ts}�] g9m&��h \"� m ] h \1u mBl�g ]?] g ["ts]z� c x � c3gi�

(*)+( � ���-,§����� � ��� ��

� l ] d"g�hs� r g�e�j3c rVt c x mil"h � d"g�c�� ] _ m¯h � mBc � hsj \ h ± _ rn\ m t e rVw�{nrV\ _ ] mBl ]¶� m r m ] c x mBl ]�r g�m&h \ c } m r h \ h \ jl"hkj3l t e ��[ g { h {nrV}�ts];� e � m ] � �DrV\�w©\"] m � c3gi� �zu�� l ] g ]z} e w h � mBg�h }"[ m ]?wª� e � m ] � �DrV\�w©\"] m � c3gi� � c x � e ��m ] � �¯r g ] _ c \"� h w"] g ]?w h \ mBl ] hsgImBcnm rVt hkm�e rV��� e � m ] � � c x � e � m ] � �zu�rn\"wªrV�&\"] m � cVgi� � c x¾\"] m � c3gi� ���g r mBl ] g�mBl rV\ �­cVg ] _ c \f{3]z\ mihsc \"rVt r d�d"gic r _ l ]?� mil r m x c _ [�� c \"t eµc \©�i]zts] _ m ]zw d"gic3d ] g9mBh ]?� c x _ ] g9m r h \�i[�}"� e � m ] � � c3gI�Zc w"["ts]z� h \ h � c t|r mBhsc \ �� c r _z_ c3�Zd t h � l mil r m¯j3c rnt h \ mBl�h � g ] d£c3g9m u aNl r d�m ] g ^�rVw"w g ]?���i]z��r�} gic rnw�� d ] _ mBg [ � c x mBl"g ]�r m �

mBc �i[ g { h {nrV} h t hkm�eV�ªaNl r d�m ] g W _ c \�� h w�] g � mBl ] c {V] g r g _ l"h \ j �i[ g { h {nrV} h t hkm�eªg ]� '[ hkg ] � ]z\ m ��\"] _ ]?���Br g9emBc �i[ gi�Zc ["\ m¶mBl"c ��] mil"g ]?r m �zu¾rn\"w4rnts� c _ c \"� h w"] g � mBl ]Z�i["} c3g w h \�r m ] g ]� P[ hsg ] � ]z\ m � c \²� l"h _ l �i[ g �{ h {nrV} h t hÂm�e ["t mihs� r m ]zt e w"] d ]z\"w"��� h \ _ tk["w h \ jªg ]zt h rV} h t hkm�e u r�{nr h t|rV} h t hÂm�e u)�i] _ [ gihÂm�e ~ _ c \�±"w"]?\ mBh rVt hÂm�e uh \ m ] j3g�hkm�e u�w"]�x®]?\"��]�r j r h \"� m w"]z\ h rVtk� c x �i] g { h _ ]FrV\"w cVmBl ] g�m�ePd ]?� c x �­h �i["��] � u d ] g x c3g�� rn\ _ ]nu h \ mBl ]d"g ]?�i]z\ _ ] c x�r _z_ h w"]?\ m rnt&rV\"w � rVt h _ hkc ["��r _ mBhkc \"�ZrV\"w � rVtkx®["\ _ mBhkc \"� c x#� c x m �Nr g ]«rV\�w l r g w��Nr g ] �aNl r d§m ] g � mBl ]z\ h w�]?\ mBh ±�]?��x®["\"w"r � ]z\ m rVtIw"]�± _ h ]?\ _ h ]z� h \ mil ] m ] _ l \ c t cVjVe r�{nr h tsrV}"ts] mBc w�r e u½rn\"waNl r d§m ] g � � r � ]?� g ] _ c3�Z� ]z\"w�r mihsc \"�Ãx c3gyl"c � mic+c {3] g _ c3� ] mBl�c �i]�w"]z± _ h ]z\ _ h ]?� � o§["}"��]� '["]?\ m_ l r d§m ] g �IrVw"w g ]?��� j [ h w"]?t h \"]z��x c3g w�]z{3]zt c3d�h \ j rV\"w g r d"h w�t e _ c \�± j [ gih \ j;l"hkj3l t e �i[ g { h {nrV}"ts]¯� e � m ] � �rV\"w4\"] m � c3gi� �zu h \ _ ts["w h \ jymBl ] d"g ]z�i]?\ m r mBhkc \ c x j ]?\"] gih _Z_ tsrV�i��]?� c x&r g _ l�hkm ] _ m [ g rVt�� mig [ _ m [ g ]?��rn\"w� cV� ]�� d ] _ h ± _ m�ePd ]z� c x)� e � m ] � � � � d�d ]z\"w h ¢�� _ c \"� h w"] g � l"c � mBl ] _ c \ m ]z\ m � c x mBl"h � g ] d£cVg�m½�ZhsjVl'm±�\"w mBl ] hsg �Nr eyh \ mBc rV\y]zw"[ _ r mBhsc \�rVt _ [ gigih _ ["tk[ �µ�

¨�]?� d"hkm ] mBl ]� '[ cVm ]?wZw h _ m [ � c x���ts}�] g9m�� h \"� m ] h \­r m�mBl ]&}�] j3h \"\ h \ jDc x mil"h � _ l r d�m ] g u'�N] c }"��] g {3]mBl r m¯j ]?\"] g rVt � d [ gid�c �i]�� e � m ] � ��rV\"wµ\"] m � c3g�� � mBl r m�� ["� m }�] l"hsj3l t e ��[ g { h {Vrn}"ts]¶r g ]¶\ cVm t hk� ]?t e­mic}�]D� hs�Zd ts] � ["\"ts]z�i� mBl ] e r g ]D��] g�hsc ["��t e migih { h rVt h�� ]zw � � l ]D\�r m [ g ] c x mBl ] d�gic }"tk] ��h � h \ mBg�h \"� h _ rVtst e_ cV�­d tk]�¢£�©]�¢ d ] g�h ]?\ _ ]ª� l"c �&� mBl r m�� rn\ e {P["tk\"] g rV} h t hkmih ]?��r g ] _ c3�Z�­c \ d t|r _ ]VuIrn\"wb\ cVm ]�rV� e�micr�{ c3h w ��mil ] d£cnm ]?\ mih rVt mBl"g ]�r m �&r g ]�{V] g9e } gic rVw"t e }�rV��]?w � _ c3�Zd ts]�¢ hÂm�eZh � c x m ]?\y}�] e3c \"w mBl ]�� _ c3d ] c xr�� � rVtkt§rn\"w _ t c �i]?t eD� \ hkm w"]�{3]zt c3d"� ]?\ m�m ]�r � �3� rV\�r j ] � ]z\ m�h � c x m ]z\�["\�r��½r g ] c x mBl ] _ c3�Zd tk]�¢ hkmih ]?�

Å

Page 20: Practical Architectures for Survivable Systems and Networks (Phase

rV\"w mil ] hkg¾hs�Zd t h _ r mBhsc \"� �)aNc \��i]� '["]z\ m t e u mil ]&r d"d�gic r _ l�c x mil"h � g ] d�c3g�m h � mic _ c \�x g�c \ m�mBl ] _ l rVtstk]?\ j ]h \ hkm �Fx®["tst j ]?\"] g rVt hkm�e u g r mBl ] g�mil rV\ � ] g ]zt e mic _ r g {V] c [ m r²� hk�­d t e � rV\�r j ]�rV}"tk] � � rVtkt½�i["}��i] m?�p&] � ] � }�] g½mil ]�x c tst c � h \ j '[ cVm ]Vu"� l"h _ l�h �¯rVts� c {3] g9eyd"hkmilfe �

��� ��� � � � � � � � � ����� � � � � � � � � � � � � ��� � � � ��� � � � � � � � � � � ��� ���ts}�] g9m&��h \"� m ] h \��

p&] _ cVj \ h��zh \ j�mBl ] _ cV�­d tk]�¢ hkm�e�h \ l ] g ]?\ m�h \��Br mBh �9x ePh \ j rV\ e�g ]�rVt h � mBh _ �i] m5c x���[ g { h {nrV} h t hÂm�eDg ]� '[ hkg ]��� ]?\ m �zu'�5] l r�{3] _ l"c ��]?\ mic _ c \"� h w"] g�mBl ]I{3] g�e w h� _ ["t m x®["tst e;j ]?\"] g rVt d"g�c }"tk] � c x1r _ l�h ]z{ h \ j¶l"hsj3l t e�i[ g { h {nrV}"tk]�� e � m ] � �¯rV\"wÃ\"] m � cVgi� �&�i["} � ] _ m&mBcFmil ]�� h w�]?� m � d ] _ mig [ � c x mBl"g ]�r m � ��´5eZm r _ � t h \ jFmBl ]j ]z\"] g rVt d"g�c }"tk] � u �5] }£]zt h ]z{3] mBl r m;� [ _ l j3g ]�r m ] g�h \"� hsj3lfm _ rV\ }�] j r h \"]zw rV\"w mil r m;mil ] g ]?��["t m �h \ j r d"d"g�c r _ l ]z� _ rV\ t cPc3� x r g�mil ] g�h \ mBc«mil ]Ãx®[ m [ g ] � q�\ mil"h �;�i]?\��i]Vu��N]y}�]?t h ]z{V] mBl r m�mBl ] g ] h ��r� hkj \ h ± _ rV\ m&c3d�d£c3g9m ["\ hkm�e h \ mBl ]�x r _ ] c x mil ] h \ mBg�h \"� h _ w h� _ ["t mBh ]z� �

(*) � ��,�-�� (*� ,N��� � � �N,����������

´ rV� h _I_ c \ _ ] d�m �5r g ] h w"]z\ mih ±�]zwZrV\"wZw"]z±�\�]?w l ] g ] mil r m r g ]I["�i]zw mBl�gic [ jVl"c [ m�mil ] g ] d�c3g9m u h \ _ ts[�w h \ j�i[ g { h {nrV} h t hÂm�e u#��] _ [ gihÂm�e u g ]zt h rn} h t hkm�e u d ] g x c3gi� rV\ _ ]Vu mBg ["� m � c3g9mBl"h \"]?���?u¶w"] d ]?\�w�rV} h t hkm�e u�rV���i[ g rV\ _ ]nu� rV\"w�r mic3g�e+d£c t h _ h ]z�?u _ c3�Zd£c � hkmihsc \�u�rn\"w w�] d ]?\"w"]z\ _ ] � o§] _ mihsc \ � � W h \ mBgic w"[ _ ]?� mBl ]�\ cVmBhkc \ c x_ cV�­d"g�c3�Zh � h } h t hkm�eV�

# � ����# �&��Q"��H ��<�� HKL H®S !¡ c3g�mBl ] d [ g�d£c ��]?� c x mBl�h � g ] d�c3g9m u � � � � � � � � � ��� � �yh � mil ]«rn} h t hkm�e c x¶r _ c3�­d [ m ] g � _ c3�Z� ["\ h _ r mihsc \� e � m ] � ��}"rV�i]zw r d"d t h _ r mBhkc \ mic �ir mBh ��x e rn\"w mic _ c \ mBh \'["] mic �Br mih ��x e _ ] g9m r h \ _ gihÂmBh _ rVt g ]� '[ hkg ] � ]z\ m �~ ] �Áj�� uP� d ] _ h ± _ g ]� P[ hsg ] � ]z\ m �5x cVg ��] _ [ gihÂm�e u g ]?t h rV} h t hÂm�e u g ]�rVt � mihs� ] g ]z� d�c \"� h {3]z\"]?���?u�rV\�w _ cVgig ] _ m \"]?��� �h \ mBl ]�x r _ ] c xIrVw§{3] g �i] _ c \"w hkmBhkc \"� � o§[ g { h {nrV} h t hÂm�e«� [�� m }£]�w"]�±�\"]?w � hkmBl�g ]z� d ] _ m;mBcymBl ]Z��] m�c xrVw�{V] g � hkmih ]z� mil r m r g ]D�i[ d�d£c ��]?w mic }�]D� hÂmBl � mBcPc w � � ePd ]?� c x�rVw�{3] g � hkmBh ]?� �­hkj3lfm&m�e§d�h _ rntst e h \ _ ts["w"]l r g w��Nr g ];x rn["t m �?u�� c x m �Nr g ]F³�rT�&�zu�r m�m r _ � � c \«� e � m ] � �¶rV\"wª\"] m � cVgi� � d ] gid ] mBg r m ]zw©} e«� rVt h _ hkc ["�["��] g �zu rV\�w ]zts] _ mBg�c3� r j \"] mih _ h \ m ] g x®] g ]z\ _ ] ��� � l ["�zu �5] r g ]Z��]?] �Ph \ j � e � m ] � ��rV\"w \"] m � c3g�� � mBl r m_ rn\ d"g ]�{3]z\ m rµ� h w�] g rV\ j ] c xI� e � m ] �­h _ x r h ts[ g ]?�DrV�¶�N]ztst5rV� d ]?\�] mBg r mBhkc \"�;rV\"w h \ m ] g \�rVt �Zh �i[��i]VurV\"w _ rV\µrVts� c�h \Ã� cV� ]���]?\"��] mic ts] g r m ]�rVw"w hÂmBhkc \�rVtRx r h tk[ g ]z� c3g½�Zh ��["�i]z� mBl r m _ rV\"\ cVm }£] d�g ]z{V]?\ m ]zw ��#� _ [ g�g ]?\ m t e w�]z±�\"]zw h \ d"g r _ mih _ ]Vu g ]� '[ hsg ] � ]?\ m � h \ ["�i] mic w"r e x c3g ��[ g { h {Vrn}"ts]­� e � m ] � �­rn\"w

\"] m � c3g�� � m�ePd"h _ rVtst e x rVtkt"x r g � l"c3g9mNc x�� l r m5h � g ]�rVtkt e \�]?]?w�]?w ��� {3]z\�� cVg �i]nu mil ] _ [ gig ]?\ m t e r�{Vr h t|rn}"ts]c3d ] g r mBh \ j � e � m ] � �ZrV\"w \"] m � c3gi� ��x rVtst5]z{V]?\ x r g�mil ] g � l"c3g�m?� aNc \"��]� '["]?\ m t e u5}£]�x c3g ]µr m�m ] �­d�mih \ jmBc w h � _ ["���F�i[ g { h {nrV}"tk]�� e � m ] � �?u hÂm;h � hk�­d�c3g�m rV\ m¶mBc ]z� m rn}"t h � l r _ c3�Zd"g ] l ]?\�� h {V] �i] m�c x g ]�rVt h � mih _g ]� '[ hsg ] � ]?\ m �Ix c3g ��[ g { h {Vrn} h t hkm�e ~KrV� h \ aNl r d�m ] g W ��� q m&h �&rVtk� c w"]z� hsg rV}"tk] mBc�h w�]?\ mBh x e x®["\�w�r � ]?\ m rVtj r d � h \Ã� l r m&h � _ [ gig ]?\ m t e r�{Vr h t|rn}"ts]F~KrV� h \ aNl r d�m ] g � ���

��h {3]z\�r¯�5]?tktÂ�¼w"]z±�\�]?w��i] m�c x g ]� '[ hkg ] � ]?\ m �?u hkm h � mBl ]?\ hs�Zd�c3g�m rV\ m)mic w"]�±�\"]&r¯x r �­h t e�c x g ]?["�irV}"tk]h \ m ] gicVd ] g rV}"tk]&}�rV�i]zt h \"]�� e � m ] � rV\�w�\"] m � c3g�� r g _ l"hÂm ] _ m [ g ]?� mil r m _ rV\­w"] �Zc \"� mBg rV}"t e r mim r h \ mBl"c ��]

������� ��������� ��� ! " $# %�&�'(# &*)�+(# %�,-.�0/1��21-435/1/467,)"&*,-��98:35%<;�=)�,21/?>@,/A�*�1+B&!C�21,5�*�#D0E &"+B&F,56��*��/G>1,/?�$6�,)F)���'B+H3581+B'B+ �JILK�&�21)�M?+ M53581+B'B+ �JI4%�,21'B>@35' �*��)�/:30�*+ ML��' I.8N� >?��O1/1��>P35&!3��1)*,8:3581+B'B+B&*�*+B%9-��Q35&�2?)��9,56R�1,Q S F��'B'��*�1� =+ ML��/

)���C�21+B)���-���/L��& 35)*��&�30��+B&�O:��>T#�UV,Q F�WML�Q)QKTC�2:35/L��+ ��30�*+ ML��-���35&*21)���&X�*��/1>P��,.8Y��ML��)*I@-�+B&�'B�Q35>1+B/1=[Z\��&��Y��%Q+H35'B' IG V�?�Q/]8:35&*��>^,/]+B/1%�,)*)���%W�,)"21/?6�,21/1>1��>G35&�&�2?-��?��+B,/?&�#`_"�1+B&F+B&"�:35)*�*+B%�21'H35)�' I��*)�21�V V�?�Q/A%�,/1&�+B>1��)*+B/1=a&���%�21)*+ �JI�K� !�1��)��X�*�1�9 !+B>1��&��1)*�Q35>G>1+B&*&���-�+B/:30�*+B,/.,56`3�/1�W V' I>1+B&*%Q,QML��)���>GM�21'B/1��)<3581+B'B+ �JI� b,21'B>G)�35>1+B%Q35'B' I4%<�:35/1=�$���?� �N��)*%Q��+ ML��>@�1)*,8:3581+B'B+ �*+B��&�c`_"��21&QK? F� �?)��W67��)!35/G2?/1C�2135/��*+ O:��>P>1�WO:/1+ �*+B,/T#

Page 21: Practical Architectures for Survivable Systems and Networks (Phase

g ]� '[ hsg ] � ]?\ m � � � hÂmBlªmil ] j3c rVtk� c x�]z\ l rV\ _ h \ jÃmil ] d"gic _ [ g ] � ]?\ m u1w"]z{V]?t c3d"� ]?\ m u _ c \�± j [ g r mBhkc \1urV���i[ g rV\ _ ]nu¶]z{nrVts["r mBhkc \1u�rV\"w cVd ] g r mihsc \ c x�� e � m ] � �ªrV\�w \"] m � c3g�� ��� hkmil _ gihÂmBh _ rVt���[ g { h {nrV} h t hÂm�eg ]� '[ hsg ] � ]?\ m � �� d�g ]?t hs�Zh \�r g�e � _ c3d"h \ j�c x mil ] j ]?\�] g rnt��i[ g { h {nrV} h t hÂm�e¶d"gic }�ts] � �NrV���i[ j3j ]?� m ]zwZ} e r;�T�3�3W g ] d�c3g9m

� gihÂmim ]?\bx c3g�mil ]©� g��;e p&]?��]�r g _ l ��rV} c3g r mBc3g9e ~®��p¯� � u � � � � � � � � � ��� � � � � ��������� � � � � � � � � � � �� � ��� �������� �� ��� � � ��� � �� � � ��� � � �� ��� � ��� � �� � � ���� � � � � � � ¹ ^V� Äv� � l r m¶g ] d�c3g�m¶c [ m t h \"]?�#r_ cV�­d"g ] l ]z\"� h {3] � ["t mih x®["\ _ mBhkc \�rVtn�i] m c x g ]�rnt h � mBh _�_ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mBhsc \��i[ g { h {nrV} h t hkm�e#g ]� '[ hkg ]��� ]?\ m ��rn\"w � r � ]?� g ]?tsr m ]zw g ] _ c3�Z� ]z\"w�r mihsc \��¾r d�d t h _ rV}"tk] mic ¬ � o � � gi�;e rV\"w;w"]zx®]z\"�i]&� e � m ] � � ��� q mrV���i]?���i]z� mBl ]�{P["tk\"] g rV} h t hkmih ]?�zu mil"g ]?r m �zuRrV\"w gih � � �¯rV�i� c _ h r m ]?wy� hkmBl r d�d t h _ r mihsc \"� g ]� '[ hkgih \ j �i[ g { h {f�rV}"tk] _ cV�­d [ m ] g � _ c3�­� ["\ h _ r mBhkc \Z� e � m ] � � � q m w h � _ ["���i]z� mil ] g ]� '[ hsg ] � ]?\ m �zuRrV\"w h w�]?\ mBh ±�]?�½{nr g�hsc ["�c }"� m r _ ts]z� mil r mZ� ["� m }�] c {V] g _ c3� ] � q m­d"g ]z�i]z\ m � g ] _ cV�­� ]?\"w"r mBhkc \"� c \ � d ] _ h ± _ w hsg ] _ mihsc \"�Fx cVgx®[ m [ g ] g ]?��]�r g _ l rV\"w w"]�{3]zt c3d"� ]?\ m½mil r m � c [�tsw � hsj \ h ± _ rn\ m t e r h w h \ mBl ]�w"]z{V]?t c3d"� ]?\ m rV\"w c3d ] g r��mBhkc \ c x�� e � m ] � � _ r d rV}"ts] c x � ]?] mBh \ j rVw�{nrV\ _ ]?w g ]� '[ hkg ] � ]?\ m �5x c3g �i[ g { h {nrV} h t hkm�eV� q m½l rV� d"g�c {3]?\ mic}�]�["��]zx®["t mBc ��p¯� rV�¯r­}"rV�i]zt h \�] m [ mBcVgih rnt�w c _ [ � ]?\ m x c3g } gih \ j3h \ j � gi�;eÃd ] g � c \�\"]?t)[ d�mic � d ]z]?wc \ � e � m ] � {§[�ts\"] g rV} h t hÂmBh ]z�DrV\"w }�rV� h _ _ c \ _ ] d�m � c x¯��[ g { h {nrV} h t hÂm�e3� q m�g ] � r h \�� mBhk� ]zt e3� o c3� ] c xhkm � g ] _ c3�Z� ]?\"w"]zw g ]?��]�r g _ l rn\"w²w"]z{V]?t cVd"� ]z\ m ]z» c3g�m � l r�{3]�� mih tst)\ cVm }£]z]?\ _ r g�gih ]zw c [ m u�rV\"w�r g ]g ]�{ h � hÂm ]zw l ] g ] �� l ] _ [ g�g ]z\ m�m ] _ l \ h _ rVt�r d"d"g�c r _ l h �y� mBg�c \ j t e �ZcVmBh {Vr m ]?w } e r _ c tstk] _ mihsc \ c x l"hsjVl t e w h � _ h �

d t h \"]zw � e � m ] � ��]z\ j3h \�]?] g�h \ j rn\"w � c x m �Nr g ]���]z\ j3h \"]?] gih \ j _ c \ _ ] d�m � mBl r m _ rV\ rVw�w � hsj \ h ± _ rV\ m t e�micmBl ] j ]?\"] g rVt hkm�e rV\"w g ]z["�Brn} h t hkm�e­c x mBl ] g ]?�i[�t m �zuRrV�½�5]?tst1rV� l r�{ h \ j � d ] _ h ± _ r d"d t h _ rV} h t hÂm�eFmBc � gi�;ew"]�{3]?t c3d"� ]?\ m � � �#} c {3] rntstvu c [ g r d"d"g�c r _ l4l ] g ]­� mig ]?���i]z� mBl ] hs�Zd�c3g�m rV\ _ ] c x½� c ["\"w4� e � m ] � rn\"w\"] m � c3g�� r g _ l"hkm ] _ m [ g ]?� mil r m �i] g�hsc [��it e rVw�w g ]z�i� mil ];\"] _ ]z�i�Br g�e ��[ g { h {nrV} h t hÂm�eÃg ]� '[ hsg ] � ]?\ m � � � l"h �r d"d�gic r _ l ]?\ m r h tk�I�i]z{V] g rVt�}�rV� h _�_ c \ _ ] d§m � mil r m r g ] _ c \"� h w"] g ]zw h \ mil ]�x c tst c � h \ j ��["}"��] _ mihsc \�� �

# � ��� � S�S�QnH � ��ST>P=FE � � !�=�ST>�� ����Q ��H ��<��¾H L H®S !� l ]�x c tst c � h \ jÃmBl"g ]?] }"[�tsts] m ]zw hkm ] � � _ c \"� h w"] g�mBl�g ]?] m�e§d ]?� c x h \�x g rV� mig [ _ m [ g ]?�z�µ~9� ��mBl ] _ gihÂmBh _ rVt\�r mihsc \"rVt h \�x g rn� mBg [ _ m [ g ]z�?u¯~K^ ��h \§x c3gi� r mBhkc \ h \�x g rV� mig [ _ m [ g ]?����[ _ l rV� mBl ] q�\ m ] g \"] m u cVg � l r m ]z{V] ghkm¶� r e ]z{ c tk{V] h \ mBc ~Kr � r mihsc \"rVt q�\�x c3g�� r mBhsc \©q�\�x g rV� mBg [ _ m [ g ]nu c3g r � t c }�rVt q�\�x c3g�� r mihsc \©q�\§x g rV��mBg [ _ m [ g ]nu c3g r o c tsr g �o e � m ] � q�\�x c3g�� r mBhsc \ q�\�x g rV� mBg [ _ m [ g ]nu c3g�d ] gil r d �­]�{3]z\ mBl ]�q�\ m ] gij rnt|r _ mBh _q�\�x c3g�� r mBhsc \­q�\�x g rV� mig [ _ m [ g ] � u�rV\"w²~ W � [�\"w"] g t ePh \ j _ c3�Zd [ m ] g � e � m ] � �&rV\"w \"] m � cVgi�'h \ j � c x m �Nr g ] �

� ����Q ��H ��<��¾H L H®S !�E ��S¸:�> 3Q�H®STH 3<�L�J)<§S¸H E�J�<�L�H J'�¼Q¸<�=�STQ � VS ��Q¸>P= � � l ]����3�f  g ] d�c3g9m ¹ �T�V� Ä c xmil ] � g ]?� h w"]?\ m�� � aNcV�­�Zh ��� hsc \ c \ aNgihÂmBh _ rVt�q�\�x g rV� mig [ _ m [ g ] � gicVm ] _ mihsc \ª~ � aIa q � � �i[ �Z� r gih�� ]?�mil ] � aIa q � � � g ] _ cV�­� ]?\"w"r mBhkc \"� g ]?tsr mBh \ j;mBc ] hsjVl'm½� r ��cVg _ g�hkmih _ rnt�\"r mBhkc \�rVt h \�x g rV� mig [ _ m [ g ]?�z�m ]?tk] _ cV�­� [�\ h _ r mBhkc \"� �Rj ]z\"] g r mBhkc \1u mBg rV\"� �Zh ��� hkc \1u�rV\"wªw h � migih }"[ mBhkc \ c x ]?tk] _ migih _ d�c �N] g�� � mBc3g �r j ]IrV\"wZw h � mBg�h }"[ mBhsc \ c x j rV� rV\�w c3h t � �Nr m ] g �i[ d"d t h ]?� �'mig rV\�� d�c3g�m r mBhkc \ � }�rV\ �Ph \ j rV\"w�±�\�rn\ _ ] �] � ] gij ]z\ _ e ��] g { h _ ]?� � rn\"w _ c \ mih \'[ hÂm�e²c x ��c {V] g \ � ]z\ m �i] g { h _ ]?� � � ] gil r d � �­c � m�hs�Zd£c3g9m rV\ mx g�c3� mBl ] d"g ]z�i]z\ myd ] g � d ] _ mBh {V] h � mBl ] g ] _ c3j \ hÂmBhkc \ mil r m {V] g9e �i] gihkc ["�­{P["tk\"] g rV} h t hkmih ]z�­rn\"w

� _!�?�G F,)�;�+B/1=�=)�,21�TK"%��:35+B)���> 8�I��b�:35)*'B�Q&��@��+B/1%<;��� E �]��� �"!��#��!%$'&)(WK +B/1%�'B21>1��> E /L���1,/LI+*F35)�/1��&,� E �]���-��!��#�"!%$.&)(<K E /1>1)��W UV,'B' F3QINc &�21)*+ M?+ M53581+B'B+ �JIX&���2?>?I/�7>?�Q%��Q35&���>TK10 E �/23&)45(WK6�!,8Y��)*� UV��+B//�%�7$8�-49� �;:+<5(<K=*b��)�/135)�>?>V�W !-435/@�%�7$7� 49�A� � (<K1B,�1/?C )���21&*&���D�8$7�-49�E� � (WKF*F35)�)�I �?35'B+B&G�D�8$7�-49�H� � ��I�&*�*�Q-�&I(WK-C �1+B'B'B+B�J<VI�;�&���)�3��D*8�-�R��#$7� E <5(<K-*b�W���K�P35/:35�:35/L� E _FMNU !J_!UF(WKF_"�1,-435&�"��35)*>1,/N�DOX� E &���� U9P5(<K"B,&����1�����*��ML��/1&*,/J�QO9� E &���� U9P5(<K"� 3521)<3/0b35='B+H3,�(� EXE K�&R>9���-49�S(<K�B��/1+T: +B'B&�,/�!)U935'B'B���1��)V� E �S� U9P5(<K<X��/1/1+B&[���*��+B/:3521��)W�Q>X&���_X(<KY�P35)�+H35/1/1�A�� F35/1&�,/+�Q>X&���_F(<K 35/1>ZCR�W����)V>V��21-435/1/]Z V�?,P>1+B> -�,&���,56!�*�1�� V)*+ ��+B/?=1#S4X)�=L35/?+\[�30�*+B,/:35'>1��&�+B=/130��+B,/1&X35)��9=+ ML��/P35&",56R�*�1� >:30�*� ,56 �*�1�$)����Y,)*�^] &"�12181'B+B%Q30�*+B,/@+B/ �^_1_ � #

`

Page 22: Practical Architectures for Survivable Systems and Networks (Phase

mil"g ]?r m � ]�¢ h � m�h \ZrVtkt mBl ]?�i] _ g�hkmih _ rnt h \§x g rV� mBg [ _ m [ g ]?� � � ] gil r d �N]� P["rVtst eFhs�Zd�c3g�m rV\ m�h � mil ] aNc3� ��Zh ��� hkc \ � � g ] _ c3j \ hkmihsc \ mBl r m�mil ]?��] _ g�hkmBh _ rVt h \§x g rV� mBg [ _ m [ g ]?�¶r g ] _ t c ��]?t e�h \ m ] g w�] d ]?\"w"]z\ m rn\"wmil r mImil ] e rntst1w"] d ]z\"w c \µ[�\"w"] g t ePh \ j _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mihsc \ h \�x g rV� mig [ _ m [ g ]?� �

� ����Q ��H ��<��¾H L H®S ! E ��S¸:�> 3E��4O ��ST>'Q�@ 3E���� �)J H�3<�S¸H®E�J H J �¼Q¸<�=zSTQ �'VS �)Q¸>P=ÃE�J C�:)H�n: ST:)>J�<�S¸H®E�J)<"L#H J'�¼Q¸<�=�STQ � VS ��Q¸>P= %)>'O�>PJ %

�= �'n: <�= S¸:�> $ J£ST>'Q�J�>'Sµ<�J'%0H S¸=�>���>§J�S �)<"L�= �'n@

3>P=�=zE�Q�= � � _ c3�­d�g ] l ]?\"� h {3]y� e � m ] � ��rV\�w \�] m � c3gi� �¼� h w"]y�i] m�c x g ]�rnt h � mBh _ g ]� '[ hsg ] � ]?\ m � h �w�]?� hkg ]zw1u ]z\ _ cV�­d rn�i� h \ j �i] _ [ gihÂm�e u g ]zt h rn} h t hkm�e u�x rV["t m�mBc tk] g rn\ _ ]nu g ]�rVt � mihs� ] d ] g x c3g�� rn\ _ ]nu rn\"wrn\ e�cnmBl ] g r m�mBg�h }"[ m ]?� \"] _ ]?���Br g9e x cVg r mim r h \ h \ j rVw"]� '[�r m ]¯� e � m ] � rV\"w�\�] m � c3gi� �i[ g { h {nrV} h t hÂm�e3�¡ g�c3� mBl"h �N��] mIc x g ]� '[ hkg ] � ]?\ m �?u hÂmNh � d�c �i� h }"tk] mic �i]zts] _ m½mBl�c �i] mil r m r g ]�� d ] _ h ± _ rVtkt e�g ]?ts]�{nrV\ mmic rV\ e w"]?� hsg ]?w � e � m ] �µ� � l ]�q�\ m ] g \"] m«h �Ã�i] g�hsc [��it e {P["ts\"] g rV}�ts] mBc w"]z\ h rVt � c x|�¼�i] g { h _ ]©r m �m r _ � �?u§t c ���i]?� c x _ c \§±�w"]?\ mih rVt hkm�e rV\"w h \ m ] j3gihÂm�e�h \ mig rV\�� �Zh �i� hsc \�u�rV\�w _ c tkt|r d �i] c x _ c \"� mihkm [�]?\ m\ c w"]z� � q�\ mBl ]¶x®[ m [ g ]nu _ gihÂmBh _ rVt�r d"d t h _ r mBhkc \"�Ir g ]Dt hs� ]?t e�mBc w"] � rV\"w�rVt m ] g \�r mih {3] h \�x c3gi� r mihsc \h \�x g rn� mBg [ _ m [ g ]z� mBl r m&d�gic { h w"] j3g ]�r m ] g �i[ g { h {nrV} h t hkm�e rV\"w hkm �I�i["} m ]?\�w"]?w g ]� '[ hkg ] � ]?\ m �?u"� hkmild r g�mih _ [�t|r g r mim ]?\ mBhkc \ mic g ]zt h rn} h t hkm�e uRr�{nr h t|rV} h t hÂm�e uRrV\"w©��] _ [ gihÂm�e � _ g�ePd�mic3j3g r d"l"h _ rVtst e }�rV��]?w_ c \�±�w�]?\ mBh rVt hÂm�e rV\�w h \ m ] jVgihkm�e u d"g�cVm ] _ mihsc \µr j r h \"� m w"]?\ h rVtk� c x �i] g { h _ ]nuRrV\"wy}�rV� h _ rVtst e r _ c3� �d ts] m ]?t e \"]�� ��] mZc x d"g�cVmBc _ c tk�Fw"]z� hsj \"]?w � hkmil �i] _ [ g�hkm�e h \ �­h \"w x gic3� mBl ] {3] g9e }�] j3h \"\ h \ j� h \ _ tk["w h \ j �i] _ [ g ] h \ m ] g�c3d ] g rV} h t hÂm�e � hÂmBl²cVmil ] g¶h \§x g rV� mBg [ _ m [ g ]?� � oP[ _ l rÃ\�r mihsc \"rVt h \§x c3g �� r mihsc \ h \§x g rV� mBg [ _ m [ g ]�� c ["tkwª}�] c x�]z\ c3g��­c [���{nrVts[�] mic ¨ c ¨ rn\"w mic�mBl ] _ g�hkmBh _ rVt�\"r mBhkc \�rVth \�x g rn� mBg [ _ m [ g ]z�?uRrV\�wy� c ["tkw«rnts� c }�]�{nrVts[�rn}"ts]#x cVg ]zts] _ mBg�c \ h _�_ c3�Z� ] g _ ] �

� ����Q ��H ��<��¾H L H®S ! E ��ST:)> �)J %�>'Q�L !�H J � 3E��4O ��ST>'Q©= !�=zST>�� =µ<�J % 3E���� �)J H�3<�S¸H®E�J = !�=�@S�> �4= � o§[ g { h {nrV} h t hkm�e4c x mBl ] _ c3�Zd [ m ] g � _ cV�­� [�\ h _ r mBhkc \ h \�x g rV� mig [ _ m [ g ]?��w�] d ]?\"w"� c \bw"]��d ]?\�w�rV}"tk] cVd ] g r mih \ j � e � m ] � rV\"w�\"] m � c3g�� ��] _ [ gihÂm�e u�w"] d ]?\"w"rV}"ts]D� e � m ] � rV\�w«\"] m � c3g��yg ]?t h �rn} h t hkm�e u"rV\"wªw"] d ]z\"w�rV}�ts] cVd ] g r mihsc \�rnt d ] g x c3g�� rV\ _ ] � � [ _ lªc x mil ];] �­d"l rV� h � h \ mBl�h � g ] d�c3g9mh � c \ mBl ]z�i]D}�rV� h _ h \§x c3gi� r mBhkc \ h \�x g rV� mBg [ _ m [ g ]z� �

o e � m ] � r m�mBgih }"[ m ]?� mBl r m r g ] d r g9mBh _ ["t|r g t e�g ]zts]�{Vrn\ m micDmil ]#r mim r h \ � ]?\ m c x��i[ g { h {nrV} h t hkm�e;h \ _ ts["w"]mBl ]¶x c tst c � h \ j"�

� ��>���)Q�H S ! � oP] _ [ gihkm�e � [�� m ]?\ _ c3�­d rV�i�Zw"] d ]?\�w�rV}"tk] d"g�cVm ] _ mBhkc \�r j r h \"� m rVtkt g ]zts]z{nrV\ m _ c \P�_ ] g \"�?u h \ _ tk["w h \ j _ c \�±�w�]?\ mBh rVt hÂm�e u h \ m ] j3gihÂm�e u r�{nr h t|rV} h t hÂm�e w�]?� d�hkm ]�r mim ] �Zd�m ]zw _ cV�­d"g�c3�Zh �i]z�?ud�g ]z{V]?\ mBh \ j w"]?\ h rVtk� c xD�i] g { h _ ]Vu d"g ]z{V]?\ mBh \ j rn\"w w"] m ] _ mBh \ j �Zh ��["�i]nu d"g�c { h w h \ j4mBhk� ]zt e g ]��� d£c \"�i]z� micyd ] g _ ] h {V]?w mBl"g ]�r m �?u�rV\"w g ]?w"[ _ h \ jÃmil ] _ c \"��]� '["]z\ _ ]z� c x�["\�x cVg ]?��]?]z\ mBl�g ]�r m � � q mh \ _ tk["w"]z��} cVmil � e � m ] � ��] _ [ gihÂm�e ~ ] �·j"� u d"gicVm ] _ mBh \ j � e � m ] � �5rV\"wZ\"] m � c3g�� �½r j r h \"� m�m r �­d ] g�h \ jrn\"w cnmBl ] g5�Zh ��["�i] � rV\�w h \§x c3gi� r mBhkc \F��] _ [ gihkm�e ~®] �·j"� u d"g�cVm ] _ mBh \ j w�r m rDrV\"w d"gicVj3g r � ��r j r h \"� mm r �Zd ] gih \ j rn\"w cVmil ] g¯�­h �i["��] ��� q m#� ["� m rV\ mBh _ hkd r m ]DrVtkt g ]?rVt h � mBh _ mBl"g ]�r m �?u h \ _ ts["w h \ jZ�­h �i["��]} e;h \"� h w"] g �?u d ]?\�] mBg r mBhkc \"��} eFc [ m � h w"] g �?uPr _z_ h w"]?\ m rnt�rV\"w h \ m ]?\ mBhkc \�rVt h \ m ] g x®] g ]?\ _ ]�~ ] �Áj"� uf]?tk] _ �migic3� r j \�] mBh _ � u�] � rn\�r mBhkc \"�zu _ c {V] g9m _ l rV\"\"]zts�zu h \�x®] g ]z\ _ ]nu�rV\"w©w�r m r r jVj3g ] j r mBhkc \"� � � l ] g ] h �� [ _ lÃ�­cVg ] mic �i] _ [ g�hkm�e�mil rV\ � ] g ]?t e­d"g�c { h w h \ j _ c \�±"w"]?\ mBh rVt hÂm�e u h \ m ] j3gihÂm�e u�rV\"wyr�{nr h tsrV} h t hkm�eV���tst _ cV�­d�c \"]z\ m � mil r m � ["� m }£] mBg [�� m ]zw h \ c3g w"] g mic r _ l"h ]z{3]½rVw"]� '[�r m ]½� e � m ] � }�] l r�{ hsc3g � ["� mr _ m ["rVtst e }£] mBg ["� m � c3g�milfe3� ~ � l ]�w h � mBh \ _ mihsc \ }£] m �N]z]?\ mil ]?��] m � c _ c \ _ ] d�m � h �Dw h � _ ["���i]?w h \oP] _ mihsc \²� � ^ � W �¦�

� M�>§L H®<��¾H L H®S ! <�J'%*<���<�HKL®<�� HKL H S ! � p&]?t h rV} h t hÂm�e©h � c x m ]z\ w"]z±�\�]?w�rV��r � ]�rV��[ g ] c x l�c � �5]?tstrZ� e � m ] � cVd ] g r m ]?��� hÂmBl"h \ hÂm �#� d ] _ h ± _ r mihsc \�� � ¡ c3g u£]�¢�r �­d ts]Vu�x rV["t m�mic ts] g rV\ _ ] _ rV\ª]?\"rV}"ts];r

Page 23: Practical Architectures for Survivable Systems and Networks (Phase

{nr g�h ] m�e c x¯rVt m ] g \"r mBh {3]?�zu h \ _ ts["w h \ j�g ]�rntÂ� mihs� ]Vu�x r h t ���irnx®]Vu�x r h t ��� c x m u�x r h t �¼x rV� m u rV\"w x r h tÂ�¼�i] _ [ g ]�Zc w"]?� c x c3d ] g r mihsc \ � ��{nr h t|rV} h t hÂm�e w"]?� d"hkm ]�� e � m ] � x r h ts[ g ]?� � [�� m }£] m r h t c3g ]?w mBc rD{nr g�h ] m�e�c x� d ] _ h ± _ \"]?]zw"�?u"� hÂmBl w h »�] g ]z\ mNm ] _ l \ h '["]z��["��]?wÃx c3g w h »£] g ]z\ m x®["\ _ mBhsc \�rVt hÂm�e u§rV�&r d"d�gic3d"g�h r m ] �q m&� ["� m rVw"w g ]?����[�\ h \ m ]z\ mBhsc \�rVt�rV\"w � rVt h _ hkc ["� _ l rV\ j ]z� h \ mil ] c3d ] g r mih \ j ]z\f{ hkgic \ � ]z\ m u h \§�_ ts["w h \ j�mil"c �i] mBl r m�g ]?��["t m x g�c3� d�c �5] g�c [ m r j ]z�5rn\"w d�c �N] g {nr g�h r mihsc \"�zu3]�r g�mBl P["r � ]z�?u§³ c§c w"�?urn\"w cVmBl ] g \�r m [ g rVtNw h �irV� m ] g � � � l ] g ]y� l"c ["tsw }�]µ\ c �i] g�hsc [����5]�r � t h \ � � mBl r m r g ] {P["tk\"] g �rn}"ts] mBcªd ] g _ ] h {3]zw mBl"g ]�r m �?u rV\�w � e � m ] � w�]?� hkj \ � l"c ["tkw }£]­w"]zx®]z\"� h {3]Ã]z\ c [ j3l mil r m;hkm rVts� crnw"w g ]z�i��]?�¯� c3� ] c x mil ] �­cVg ]��i] gihkc ["�&["\�rV\ mih _ hkd r m ]?w mBl"g ]�r m � �

� 8#>PQ �¼ERQ �4<�J'3> � � r g�mBh _ ["tsr g t e²h \ g ]�rVt � mihs� ]­� e � m ] � �zu d ] g x c3gi� rV\ _ ] m ]z\"w"� mic }£]yr _ gihÂmBh _ rVtg ]� '[ hkg ] � ]?\ m?� q�\«� cV� ] _ rV��]?�zu1rVw"]� '[�r m ] d ] g x c3g�� rn\ _ ] � r e }�] _ gihÂmBh _ rVt micZmil ];��[ g { h {nrV} h t hÂm�ec x mBl ]#�i] g { h _ ]z� d"g�c { h w"]?wÃ} e rV\ ]?\ m ] gid�gih ��] c3g rV\Ãr d�d t h _ r mihsc \ � º \ mBl ] cVmBl ] gNl rV\"w1u h \ �Zc � m_ rV�i]z�?u d ] g x c3gi� rV\ _ ] h � hÂm ��]?tkxNw"] d ]?\�w"]?\ m�c \ �i[ g { h {nrV} h t hkm�e rV\"w r�{nr h t|rV} h t hÂm�e � h x½r�� e � m ] �h �;\ cnm �i[ g { h {nrV}"tk]Vu rVw�]� '[�r m ] d ] g x c3g�� rV\ _ ] _ rV\"\ cnm }£] r _ l"h ]�{3]zw � � c r�{ cVh w mBl�h �Fr d"d r g ]?\ mh \ m ] g w"] d ]?\�w"]?\ _ ]²t cPc3d u hkm � c [�tsw }�] d£c �i� h }"ts] mBc g ]zw"]z±"\"] d ] g x c3g�� rV\ _ ] g ]� '[ hsg ] � ]?\ m �yrn�}�] h \ jª� ]�rV\ h \ j x®[�tst e � d ] _ h ±�]?w c \�t e � l ]?\ mil ] g ]zts]�{Vrn\ m � e � m ] � �­r g ]Ãr�{nr h tsrV}"tk] � ( c �N]�{3] g umil"h �5�i]z] � � mBc }�]�r _ c3d � c [ m u§}£] _ rV["��] c x mBl ]�\"]?]zw mBc ]z\"�i[ g ]¶rVw"]� P["r m ] d ] g x c3gi� rV\ _ ] mBl r m½h �hÂm ��]?tkx _ gihkmih _ rVt mic ��[ g { h {Vrn} h t hkm�e3�

¿�l r m�h � hs�Z� ]?w h r m ]zt e c }'{ hkc ["� h � mil r m _ t c �i] h \ m ] gig ]?t|r mBhsc \"� l"hkd �&]�¢ h � m r �Zc \ j�mBl ]�{nr gihkc ["� g ]�� '[ hsg ] � ]?\ m � � ¡ c3g ]�¢�r �­d ts]Vu _ c \"� h w"] g&mil ]�{nr gihkc ["�½x c3g�� � c x r�{Vr h t|rn} h t hkm�e3� ��{nr h t|rV} h t hÂm�e�h � _ ts]�r g t e r�i] _ [ g�hkm�e�g ]� '[ hkg ] � ]?\ m h \�w"]zx®]z\"w h \ j r j r h \�� m�� rVt h _ hkc ["� r mim r _ � � � q m h � _ ts]?r g t e r g ]?t h rV} h t hkm�e�g ]� '[ hkg ]��� ]?\ m h \Fw"]zx®]z\"w h \ j r j r h \"� m l r g w��Nr g ] � rVtkx®[�\ _ mihsc \"�zun[�\�rV\ mBh _ hsd r m ]zwF� c x m �Nr g ]N³Rr��&�?uf]z\'{ hkgic \ � ]?\P�m rnt _ rn["�i]z�?u)rV\"w²r _ m � c x ��c w � q m�h ��rVtk� c r d ] g x c3gi� rV\ _ ] h ���i["]nu h \ mil r m rVw�]� '[�r m ]�rT{nr h t|rV} h t hÂm�e h �]?���i]z\ mih rVt micµ� r h \ m r h \ h \ j rnw"]� '[�r m ] d ] g x c3g�� rV\ _ ]�~KrV\�w _ c \f{3] g �i]zt e u�rVw"]� P["r m ] d ] g x cVgi� rV\ _ ] _ rV\}�]D]z�i��]?\ mBh rVt mBcZ� r h \ m r h \ h \ j rVw"]� '[�r m ]Dr�{nr h tsrV} h t hkm�e uPrV�&\ cVm ]zw«rn} c {3] ���¿�l ] g ]�rn� hÂm�h � _ c \ _ ] d�m ["rVtst e�d�c �i� h }"tk] mBc _ c \"� h w"] g�mBl ]?�i]�w h »�] g ]?\ m�� rV\ h x®]?� m r mBhkc \"� c x"r�{nr h tsrV} h t hkm�e

rV�&�i] d r g r m ] g ]� P[ hsg ] � ]z\ m �?u mBl�h � h �I{3] g�ey�Zh ��ts]�rnw h \ j � }�] _ rV["�i] mBl ] e r g ] _ t c ��]?t e _ c [ d ts]?w h \ mBl ]w"]z� hsj \ rn\"w hs�Zd ts] � ]z\ m r mBhkc \ c x g ]�rVt¾� e � m ] � ��rn\"w²\"] m � c3gi� � � ���¶r _ c \"��]� '["]z\ _ ]nu �5]Z� mBg ]?�i� mBl ]\ cVmihsc \ c x r g _ l�hkm ] _ m [ g ]z� mil r m rVw"w g ]?��� mil ]?��]���]?] �Zh \ j t e w h »£] g ]z\ m�g ]� '[ hkg ] � ]?\ m � h \�rn\ h \ m ] j3g r m ]zw�Nr e�mBl r m&d ] g��­hÂm � mil ] g ]?rVt h�� r mihsc \ c x)w h »£] g ]?\ m&g ]� P[ hsg ] � ]z\ m �I� hkmil"h \yr _ cV�­�Zc \ � mBg [ _ m [ g ] � � l"h �h � d [ g ��["]?wµx®[ g�mil ] g&h \�o§] _ mihsc \µW � � �

# � ��� � ANQ � =zS�C;E�QTS¸:)H J)>P=�=��Ã>PO�>PJ'%)< �¾H LKH S !

�<"J % =�= �)Q¸<�J'3>

¡ ["\"w�r � ]z\ m rVt mBcDmBl"h � g ] d�c3g9m r g ] mBl ]¯\ cVmihsc \"� c x mBg ["� m � c3g�mil"h \�]?�i�zu�w"] d ]z\"w�rV} h t hÂm�e uPrV\"w­rV���i[ g rV\ _ ] �

� A5Q �)=zS�CFERQTS¸:)HKJ�>P=�= ��>'Q�= � =½STQ �)=zS � q�\ mBl ] d"g ]z�i]z\ m _ c \ m ]�¢ m u �� � ��� � � � �& � � ������h �)r � ]?rV�i[ g ] c xl�c �+]�¢ m ]z\"� h {3]zt e r jVh {3]z\ �Zc w"["ts]nuf� e � m ] � u§\�] m � c3gi� u c3g cVmBl ] g ]?\ mBhÂm�e w"]?��] g {V]?� mic }�] mBg ["� m ]?wmic �ir mBh ��x e�hÂm ��� m r m ]zw g ]� '[ hsg ] � ]?\ m ��� l ]z\ _ c \�x gic \ m ]?w�� hÂmBl r g } hkmBg r g�e#mBl"g ]�r m � � q�\ mBl ]5��] _ [ gihkm�e_ c3�Z� ["\ hÂm�e u mig ["� m � cVg�mBl�h \"]z�i� h � g�c [ j3l t e ]� '[ h {nrVtk]?\ m�mic � l r m�h � _ rVtkts]?w��9w"] d ]?\"w"rV} h t hkm�e�� h \mil ]½x rV["t m � mBc tk] g rn\ _ ] _ c3�Z� ["\ hÂm�e ufrnt mBl�c [ j3l w�] d ]?\"w�rn} h t hkm�e �½rV� c3g�hsj3h \�rVtkt e�g ]?ts]�{nrV\ m d"gihk� r g�h t emic­mil ] mBl�g ]�r m � h \ m ]?\"w�]?w mBc }£] _ c {3] g ]?w�} e x rn["t m¯mBc tk] g rV\ _ ]nu�rn\"w©w h w�\ cVm ]z\ _ cV�­d rn�i�#� l r m�5] g ]zx®] gDmic«l ] g ] rn� mBg ["� m � c3g9mBl"h \"]?��� � ~ q�\ mil ] d"g ]?��]?\ m _ c \ m ]�¢ m u � ��� � � � ���� � _ c \"� h w"] g ]?w}�]?t c � � g ]?tsr m ]z� mBcµmBl ] _ ] g9m r h \ m�e � hÂmBl � l"h _ l mig ["� m � c3g9mBl"h \"]?��� c3g w"] d ]?\"w"rV} h t hkm�e _ rV\ }�]

Page 24: Practical Architectures for Survivable Systems and Networks (Phase

}�]?t h ]�{3]?w�u�x c3g ]�¢�r �Zd ts]nu mil"gic [ j3l«mil ];["��] c x m ]?� mih \ j rV\"w«x cVgi� rVt)rV\�rVt e ��]?� �À� q�\ mBl"h � g ] d£cVg�m umil ]#\ cVmBhkc \ c x mBg ["� m � c3g�mil"h \�]?�i�N]?\ _ c3�­d rV�i��]?�&rVtktRrV� d ] _ m � c x1�i[ g { h {nrV} h t hkm�e u h \ _ ts["w h \ j¶mBl ]¯x®["tst� d ] _ mig [ � c x mBl�g ]�r m � mBc �i[ g { h {nrV} h t hÂm�e rV\�w hÂm �I��["} m ]z\"w"]zw g ]� P[ hsg ] � ]z\ m � �� g [�� m � c3g�mil"h \"]z�i� h � d r g9mBh _ ["t|r g t e²g ]?tk]z{nrV\ mFh \ � hkm [�r mihsc \"�¶� l ] g ] mBl ] g ]yr g ] _ gihkmih _ rVt g ]� '[ hkg ]��� ]?\ m �?u mBl r mNh �zu'� l ] g ]#w"] d ]?\"w�]?\ _ ] c \ mBl ] mBg ["� m � c3g9mBl"h \"]?��� c x�� d ] _ h ± _ ]?\ mBhÂmBh ]?� h � _ g [ _ h rnt micmil ] c {3] g rVtkt�}�] l r�{ hsc3gIc x¾rF� e � m ] � c3g \"] m � cVgi�Ãh \ mil ]�t|r gij ]�� d r g�mih _ ["t|r g t e � hÂmBlÃg ]z� d ] _ m¯mic��[ g { h {Vrn} h t hkm�e uR��] _ [ gihkm�e u�rV\"w g ]?t h rV} h t hÂm�e3� q�\ mBl ]Fx rn["t m � mBc ts] g rV\ _ ] _ c3�Z� ["\ hÂm�e u�w�] d ]?\"w�rn} h t hkm�em ]?\"w�� mic }£]Zr � ]?rV�i[ g ] c x l"c � �N]ztst mil ]�� d ] _ h ±�]zw x rV["t m � mBc tk] g rn\ _ ] g ]� '[ hkg ] � ]z\ m �;r g ] � ] m urnt mBl�c [ j3lÃg ] _ ]z\ m ["�ir j ] h � j ]?\"] g rVt h��?h \ jFmBl r mImBc�cVmil ] g&g ]� '[ hsg ] � ]?\ m � �� _ r g ]�x®["t w h � mBh \ _ mBhkc \ h � � rVw"] l ] g ]�}�] m �5]?]z\ mBg ["� m rV\"w mBg [�� m � c3g�mil"h \"]z�i� � � g ["� m;h �¶� c3� ]��mil"h \ j�e3c [ r mimigih }"[ m ] mBc rµ� e � m ] � ]?\ mBhÂm�e u � l ] mBl ] g;mBl r m ]?\ mihkm�e h � mBg [�� m � c3g�mil'e4c3g \ cVm�� �mig ["� m � cVg�mBlfe ]z\ mihkm�eÃh � c \"] mBl r m w"]?��] g {V]?� mBc }£] mig ["� m ]?w �q�\ j ]?\"] g rVt�["�ir j ] h \ mil ]#t hkm ] g r m [ g ]nuPr mBg ["� m ]?wÃ� e � m ] � h � c \"] mBl r mN� [�� m }�] mig ["� m ]zw h \ cVg w"] gx cVg r d"d t h _ r mBhsc \"��["� h \ jymBl ]Z� e � m ] �/mic }�] l r�{V] d"g�c3d ] g t e3� q�w"]�rVtkt e u mig ["� m ]zw4� e � m ] � �;� l"c ["tkw}�] mBg ["� m � c3g9mBlfe u�rVt mBl"c [ j3l�mBl r m&h � c x m ]?\y\ cnmImBl ] _ rV�i] � ¡ c3g ]�¢�r �Zd ts]nu mBl ]�\ cVmBhkc \ c x mBg ["� m ]?w_ c3�Zd [ mBh \ j }"rV�i]z��~Ko§] _ mBhkc \�  � ^ ��h � g ]?rVtst e _ c \ _ ] g \�]?w²� hkmBlªmig ["� m � cVg�mBl�h \"]z�i� c x _ cV�­d�c \"]z\ m �mil r m u1}£] _ rV[��i] c x mBl ] hsg x®["\ _ mBhkc \�rVt hkm�e u l r�{3] mBc }�] mBg ["� m ]?w � rV\"w mBl r m�mBl ] g ]�x c3g ] � [�� m }�]mig ["� m � cVg�mBlfeV�

� �Ã>'O�>PJ %�<�� HKL H S ! <�J'% <"=�= ��Q�<"J 3> � q�\ mBl�h � g ] d�c3g�m uP�5] g ]zx®] g5c \"t e t c§c �i]?t e�mBc � � � ���� � � � ��� � � �rn� mil ]�]�¢ m ]?\ m mic � l�h _ l r j3h {V]?\ g ]� '[ hkg ] � ]?\ m­h � d ] g _ ] h {V]?w mic }�]��ir mBh ��±�]zw1u d r g�mBh _ ["tsr g t e} e mBl ] hk�­d tk] � ]?\ m r mBhsc \ ��� ��� � � � �����h � mil ]?\ mBl ] _ g ]?w h } h t hkm�e4mil r m _ rV\+}£] j3h {V]?\ mic � d ]��_ h ± _ � m r m ] � ]z\ m � c x�w"] d ]z\"w�rV} h t hÂm�e rV\"w mig ["� m � cVg�mBl�h \"]z�i� � � l ["�?uIx c3g ]�¢�r �Zd tk]Vu5�5] �ZhsjVl'mg r mBl ] g � d ] _ h ± _ rVtst e g ]zx®] g½micZmil ]¶rV���i[ g rV\ _ ] c x mBl ]¶w"] d ]z\"w�rV} h t hÂm�e c x mBg ["� m � c3g9mBl"h \"]?���¯� hÂmBl"h \r d r g�mBh _ ["tsr g � e � m ] � w�]?� hkj \ c3g&hkm � hk�­d tk] � ]?\ m r mBhsc \1u�rnt mBl�c [ j3lÃh \ j ]z\"] g rVt1�5];r g ] d"gihk� r g�h t e_ c \ _ ] g \�]?w­� hÂmBl�mBg ["� m � c3g�mil"h \�]?�i� hkm �i]?tÂx1rn\"w�r�{ c3h w mBl ] _ hsg _ [ � t c _ [ mihsc \ � � l ] g ]?rVw"] g � h tst"\ cnm��[�»£] g } e rV���i[ �Zh \ jÃmil r m�mBl ]�rV�i��[ g rV\ _ ] c x mBg [�� m � c3g�mil"h \"]z�i��rV\"w mBl ] d�g ]?w h _ m rV} h t hkm�eµc x5w"]��d ]?\�w�rV} h t hkm�e ~®] �·j"� u ¹ W���W Ä|� r g ] h \"w"]z]?w mBl ]I�ir � ] _ c \ _ ] d§m ~ c3g u'r m ts]?rV� m u _ t c �i]zt e ]?\ c [ j3l�g ]?tsr m ]zwx cVgId"g ]z�i]?\ m�d [ g�d£c ��]?� ���� l ]½x c3g ] j3c3h \ j _ c \ _ ] d§m � � ��[ g { h {nrV} h t hÂm�e un�i] _ [ gihÂm�e u g ]zt h rV} h t hkm�e unrn\"w d ] g x c3g�� rn\ _ ] � \"]?]zw mic}�] hs�Zd tk] � ]?\ m ]zw h \Ã��[ _ l rF�Nr e mBl r m½mBl ]�w�]?� hkg ]zw d"g�c3d ] g�mih ]z� _ rV\y}�]¶r _ l"h ]z{3]zw�w�] d ]?\"w�rn}"t eV�¨�]�x®]?\"� h {V] � ]?rV�i[ g ]?� h \ _ tk["w"]«]z� m rV}"t h � l"� ]?\ mÃc x;r d"d"gicVd"gih r m ] g ]� '[ hkg ] � ]z\ m �?u j3c§c wb� e � m ] �w�]?� hkj \ mil r m�h � _ c \"� h � m ]z\ m � hkmBl�mBl ] g ]� '[ hsg ] � ]?\ m �zu j3cPc w«� e � m ] � w�]z{3]zt c3d�� ]z\ m rn\"w _ c w h \ jd�g r _ mBh _ ] h \ _ ts["w h \ j mBl ]�["��] c x �­c w"] g \ � c x m �Nr g ] ]?\ jVh \"]z] gih \ j rV\"w � c ["\"w d"gicVj3g r �Z�Zh \ jtsrV\ j ["r j ]?��rV\"w©w�] �Zc \"� mig r mihsc \�� mil r m�hk�­d ts] � ]?\ m r mBhkc \"�¯r g ] _ c \�� h � m ]z\ m � hÂmBl«mil ] hkg w�]?� hkj \"�zurn\"w cVd ] g r mihsc \�rnt d"g�c _ ]?w"[ g ]?� mBl r mD� r h \ m r h \ mil ] h \ m ] j3gihÂm�eªc xNw"]?� hsj \ rV\"w hs�Zd ts] � ]z\ m r mihsc \w�]?� d�hkm ] c \ j3c3h \ j w"]?}"[ j3j3h \ j rn\"w � r h \ m ]?\�rn\ _ ] � rV\�w d�cVm ]z\ mBh rnt �Zh �i[��i] �

� =?= �)Q¸<�J'3>4<"J % <"J)<�L�!1S¸H��%�>PO�>PJ'%)< �¾H LKH S ! � º {3] g rVtkt¾� e � m ] � rV\"w©\"] m � cVgi� ��[ g { h {nrV} h t hÂm�e� l"c ["tkw«}�] d�g ]?w h _ m rV}"t e w"] �Zc \"� mBg rn}"ts]D} e�� ] mil"c w"� cnmBl ] g�mBl rV\«� hs�Zd t e m ]?� mBh \ j"� ¡ c3g ]�¢�r � �d ts]Vu1x cVgi� rVt � ] mBl�c w"� _ c ["tsw²}�]�["�i]zw mBc w"] �­c \�� mBg r m ] mil ]ZrVw"]� '[�r _ e²c x mBl ] g ]� '[ hsg ] � ]?\ m �zumil ] _ c \"� h � m ]z\ _ e c x mBl ]y� d ] _ h ± _ r mBhkc \"�;� hÂmBl mBl�c �i] g ]� '[ hsg ] � ]?\ m �zuNrn\"w mBl ] _ c \"� h � m ]?\ _ e c xmil ] hs�Zd ts] � ]z\ m r mihsc \«� hÂmBl²mBl ]Z� d ] _ h ± _ r mBhkc \"�zu r m w h »£] g ]z\ m tsr e ] g � c xIrV}"� mBg r _ mihsc \1u)rV\�w mBl ]_ c \"� h � m ]?\ _ e c x c \�]�tsr e ] g � hkmil rV\ cVmBl ] g?��º#mil ] g _ c \"� mig [ _ mBh {V]ªrV\"rVt e'mBh _ r gij [ � ]z\ m � _ c ["tkw

Page 25: Practical Architectures for Survivable Systems and Networks (Phase

� ]�rn�i[ g ] mBl ]�rV�i��[ g rn\ _ ]#� hÂmBl � l�h _ l r;� e � m ] � r g _ l"hkm ] _ m [ g ] �­hkj3lfm ��[ g { h {3]�� d ] _ h ± _ m�ePd ]z� c xmil"g ]?r m �zu"]z{V]?\µw"]?� d"hkm ]�["\�rV\ mih _ hkd r m ]?wy]z{V]?\ m � � ��\�rVt e'mih _ mic§c tk�½r g ]¶rVts� c ["��]zx®["t h \Ã["\ _ c {V] gih \ j³�rT�&��rV\"w '["]?� mBhkc \�rV}"tk] _ c w h \ jyd"g r _ mih _ ]?� h \²� c x m �½r g ] � � r gihkc ["�Dr d"d"g�c r _ l ]z� mic rV�i��[ g rV\ _ ]]�¢ h � m u h \ _ ts["w h \ j x cVgi� rVt � ] mil"c w��¯w h � _ ["�i��]?w h \�o§] _ mBhkc \�� � � �

� r g�hsc ["� cVmBl ] g r mimigih }�[ m ]z�&r g ]DrVtk� c�l"hsjVl t e w"]?� hsg rV}"ts] h \y]?\"��[ gih \ j w�] d ]?\"w�rn}"ts]¶�i[ g { h {nrV} h t hÂm�e3�

� ��� �¾= !�=zST>�� 3E��4O�E�=?<�� HKL H®S ! � o§["}"� e � m ] � �ZrV\�w _ c3�Zd�c \"]?\ m �F� l"c ["tsw }�] w"]z� hkj \"]?w rn\"whk�­d ts] � ]?\ m ]?w mic ]?\ l rV\ _ ] mBl ]F]?rV�i]F� hÂmBl � l�h _ lªmBl ] e _ rV\©}�] h \ m ] j3g r m ]zw mBc3j ] mBl ] g � hÂmBl"c [ mrnw�{3] g �i]zt e rn»£] _ mBh \ j �i[ g { h {nrV} h t hkm�eV� aNc3�Zd£c �BrV} h t hÂm�e­h � _ c \�� h w�] g ]zw�x®[ g9mBl ] g&h \µo§] _ mBhkc \«� � � �

� $ J£ST>'Q¸ERO�>'Q�< �¾H LKH S ! � q�\ m ] gicVd ] g rV} h t hÂm�e � l"c ["tsw�}£]�]�rV� h t e r mim r h \�rV}�ts]Vu5r _ gic ����w h »�] g ]?\ m \"] m �� c3g�� �zu�� e � m ] � �?u���["}"� e � m ] � �zu�rn\"w r d"d t h _ r mihsc \+�i] g { h _ ]z� � � r gihkc ["� d t|r m x c3gi� � � l�c ["tsw }�]r _?_ cV�­�Zc w"r m ]zw1u h \ _ tk["w h \ j²� r h \�x g r � ]z�?u �­h \ h �zu�� c3gi� � m r mihsc \"�zu d ] g � c \�rVt _ cV�­d [ m ] g �?uIrn\"w_ c3� } h \�r mihsc \"� mBl ] g ] c x � ¡ hkg ]z�NrVtkts�Frn\"w cVmBl ] g _ c \ mBg�c ts�;\"] _ ]?�i�ir g�e x c3g �i] _ [ gihÂm�e � l�c ["tsw \ cnm[�\"w"["t e hs�Zd ]zw"] h \ m ] g�c3d ] g rn} h t hkm�e � l ] g ]ªrV[ mBl�c3gih�� ]?w � p&]?tk]z{nrV\ m � m rV\�w�r g w���� l�c ["tsw�}£] g ]��� d ] _ m ]?w1uR}"[ m¯h \�rVw"]� P["r m ]�� m rV\"w"r g w"� � ["� m }£] g ] d tsr _ ]zw1u�[ d"j3g rVw"]zw1u c3g ]�¢ d t h _ hÂm t e­hkj \ c3g ]?w �

� ��3<�L®<�� HKL H®S ! � � l ]ÃrV} c {3]�� � ]z\ mBhsc \"]?w _ c \ _ ] d�m � � ["� m }�] _ r d rV}"tk] c x&rnw�r d�mih \ jµmBc r g rV\ j ]c x cVd ] g r mihsc \"�zu x gic3� t c _ rnt c3d ] g r mBhkc \ mBc � h w"]?t e w h � d ] g �i]zw�� e � m ] � �zu�x g�c3� r«x®]�� ["��] g � micr _ c \"� h w"] g rV}�ts] _ c3�­� ["\ hkm�eµc x�["��] g �?u1x gicV� r _ t c ��]?w _ cV�­� [�\ hkm�eymBc rV\ c3d ]?\§�¼� e � m ] � ]z\'{ h �g�c \ � ]?\ m�� ¿�l ] g ]¶� h \ j tk]¶r d"d"g�c r _ l ]z�¯r g ]�\ cnm r d"d t h _ rV}�ts]Vu mBl ] d r g r � ] m ] g�h�� ]zw _ c \�± j [ g r mBhsc \� l"c ["tkw d ] gi�Zhkm rVw"r d�m r mBhsc \yr _?_ c3g w h \ j�mBc�mBl ]D� d ] _ h ± _ g ]� '[ hkg ] � ]?\ m � �

� � =zSTQ¸< VSTH E�J � � m ]�r _ lyc x1{nr g�hsc [��Nt|r e ] g � c x)rV}"� mBg r _ mihsc \1u hs�Zd tk] � ]?\ m r mihsc \�� � ["� m }£] d"gic3d �] g t e ~®] �·j"� u���[ g { h {Vrn}"t e u��i] _ [ g ]zt e u5rn\"w g ]zt h rn}"t e�� ]?\ _ r d �i[�t|r m ]?w1u�� hkmil r d"d"g�c3d"g�h r m ] h \§x c3gi� r��mihsc \ l"h w h \ j rV\"w l"hkj3l � h \ m ] j3gihÂm�e hs�Zd ts] � ]z\ m r mBhkc \ � o e � m ] � h \ m ] g x r _ ]?� rn\"w d"gicVj3g r �Z�Zh \ jtsrV\ j ["r j ]?� � ["� m¯d"g�c { h w"]¶�i[ hÂm rV}�ts]¶rV}"� mBg r _ mihsc \"�zu�rV\"w � ["� m }£]�\ c \P} ePd rV���BrV}�ts] �

� 8DQ¸>��£>PJ£STH E�J�%�>'S�> VSTH E�J

�STE�L >'Q¸<�S¸H®E�J

�<�J % Q¸>P<�VS¸H E�J � � ] hÂmBl ] g­d"g ]z{V]?\ mBhkc \b\ c3g w"]��

m ] _ mBhsc \ h �#rVw"]� P["r m ]�} e�hkm �i]ztkx � �#\©r d�d"gic3d�gih r m ]D}�rVt|rn\ _ ] � ["� m }£]Dx c ["\"w«}£] m �N]z]?\ mBl ] m � c u[ mBh t h��zh \ j _ c \"� mig [ _ mBh {3]Iw"]z� hsj \ m ] _ l \ h '["]z� rV� �5]?tkt�rn� d"g�c r _ mih {V]Nw"] m ] _ mBhkc \ c x�]�{3]?\ m � mBl r m¾� r e}�]&�i["� d"h _ hsc [�� � hÂmBlZg ]z� d ] _ m5mBc¶mBl ] g ]� '[ hsg ] � ]?\ m � x c3g �i[ g { h {nrV} h t hÂm�e u3��] _ [ gihkm�e u g ]?t h rV} h t hÂm�e u3rn\"w� c x c3g9mBl1� q�\ rVw�w hkmihsc \1u mic ts] g r mihsc \ c x&rVw§{3] g �i]Ã]�{3]?\ m � mBl r m _ rn\"\ cVm }£] d"g ]�{3]?\ m ]?w � ["� m }�]d t|rV\"\�]?w h \y� e � m ] � w"]z� hkj \1u hsg�g ]z� d ] _ mih {V] c x � l ] mBl ] g w�] m ] _ mihsc \µ�i[ _z_ ]z]?w"� � � g rVw hÂmBhkc \�rVt�x rV["t mmic ts] g rV\ _ ] h � h \ m ]?\�w"]?w mic _ c3� }�r mFg ]?t h rV} h t hÂm�e � g ]zt|r m ]?w mBl�g ]�r m �?u � l ] g ]�rV� hÂm � _ c ["\ m ] gid r g�m�h \��] _ [ gihÂm�e � g ]zt|r m ]?w mBl�g ]�r m � � ["� m }£] mBc � hkmil � m rV\"w mBc � l r m ]�{3] g w"] j3g ]z] d"g r _ mBh _ rV}�ts] � rVt h _ hkc ["�r mim r _ � � mil r m _ rV\"\ cVm }�] d"g ]z{3]z\ m ]?w � ¡ h \�rVtkt e u�� d ]?]zw e�g ]?r _ mihsc \ h ��\"] _ ]?���Br g9e � l ]?\Z� c3� ] mil"h \ jrnw�{3] g �i] l rV�&}�]?]z\�w"] m ] _ m ]zw mil r m _ rV\�\ cVm }£] mic ts] g r m ]?w �

� �Ã>'O�>PJ %�>PJ fH®>P= <�J'% H J£ST>'Q¸Q¸>§L®<�S¸H®E�J =?: H®O¾= � q�\ rV\ e w h � migih }�[ m ]zw�� e � m ] � r g _ l�hkm ] _ m [ g ]nu� l ] mBl ] gyl"h ] g r g _ l"h _ rVtst e tsr e ] g ]?w c3gyl"hsjVl t e�h \ m ] gig ]?t|r mBhsc \�rVtvu hÂmyh �Ã["\�w"]?� hsg rn}"ts] mic l rT{V] micw�] d ]?\"w c \ h \ l ] g ]?\ m t e ts]z�i� mig ["� m � c3g9mBlfe _ cV�­d�c \"]z\ m ��� � hkmil g ]?� d ] _ mZmBc ��] _ [ gihkm�e u g ]?t h r��} h t hÂm�e u�rn\"w4r�{nr h t|rV} h t hÂm�e3� q¼x½�i[ _ l rVw�{V] g �i]�w�] d ]?\"w"]z\ _ ] h ��]z�i�i]z\ mBh rnt mic��Zh \ hs�Zh�� ] c3g _ c \ migic tl r gi� x®["t�]�»�] _ m �?u hkmI� ["� m }�]¶w"] �Zc \"� mBg rn}"t e \ cVm&h \ _ c \�³ h _ m � hkmil mBl ]¶w"]z� hkg ]?w g ]� '[ hsg ] � ]?\ m � �¡ c3g ]�¢"r �­d tk]Vu�w"]?rVw"t c _ � � _ rV\4}�] _ rV["��]?w r _z_ h w"]?\ m rntst eªc3g¶h \ m ]z\ mihsc \"rVtst e u�rV\"w _ rV\ g ]z�i["t m;h \w�]?\ h rVts� c x)�i] g { h _ ]�[�\"ts]z�i� mBl ]#� e � m ] � r g _ l"hkm ] _ m [ g ] m r � ]z�&]�¢ d t h _ hÂm½� ]�rV��[ g ]z� mBc r�{ c3h w mBl ] ���

Page 26: Practical Architectures for Survivable Systems and Networks (Phase

¨�]�{nrV� m r mBh \ j _ c \��i]� '["]z\ _ ]z� _ rV\ g ]z�i["t m x gic3� w�] d ]?\"w"]z\ _ ] c \�[�\ mig ["� m � cVg�mBlfe _ cV�­d�c \"]z\ m �mil r m r g ]�\"]z{V] g�mil ]?tk]?��� h tktÂ��rVw�{ h ��]?w"t eÃmBg [�� m ]zw � q m�h �¶rVts� c w"]?� hsg rn}"ts] micµh w"]?\ mih x e rn\"w4rn\�rVt e � ]mil ] h \ m ] g r _ mihsc \��#r �Zc \ jZmBl ];w h »£] g ]?\ m�g ]� '[ hsg ] � ]?\ m � � � hÂmBlªg ]?� d ] _ m�mBc­mBl ] g ]� '[ hkg ] � ]z\ m �mil ] � �i]ztk{V]?�?u rn�;�N]ztstNrV�;� hkmil g ]z� d ] _ m�mBc _ c \�³ h _ m � mBl r m;� r e r gih �i] h \ mil ] w"]z� hsj \ rV\"w hk� �d ts] � ]?\ m r mBhkc \ � q¼x d£cVm ]?\ mBh rVtst e _ c \�³ h _ mih \ j _ c \"�i]� P[�]?\ _ ]?� _ rn\«r g�h ��]Vu mil ] d�gihscVgihkmih ]z�½\"] _ ]?���Br g9emicyg ]?� c tk{V] mBl"c ��] _ c \�³ h _ m �¶� l"c [�tsw²}£]�]z� m rn}"t h � l ]zw h \�rVw�{nrV\ _ ]Vu h \"� c x r g rV� d�c �i� h }"tk] � ���DrV\]�¢�r �­d ts]Vu _ c \�� h w�] g¾mil ]N["��] c x�rVt m ] g \�r mih {3] _ cV�­d�c \"]z\ m � c3g g ]?w�["\"w�rV\ m _ c3�­� ["\ h _ r mBhkc \ d r mil �micªh \ _ g ]?rV�i] rT{nr h t|rV} h t hÂm�e �¾c \"]�["\"w"]z� hsg rV}"tk] _ c \"�i]� P[�]?\ _ ] _ c ["tsw4}£] h \ _ g ]�rV��]?w ]�¢ d�c �i[ g ]?� mic��] _ [ gihÂm�e r m�m r _ � � g ]?�i[�t mBh \ j x g�c3� mBl ]�rnw"w hkmihsc \"rVt c } � ] _ m � c x�r mim r _ ��� � l"h � h � � ["� m�c \"] �Zc3g ]]�¢�r �­d ts] c x mBl ] hk�­d�c3g9m rV\ _ ] c x�["\"w�] g � m rV\�w h \ j²mBl ]Ãw"] d ]?\"w�]?\ _ h ]?�­rV\"w h \ m ] gig ]?tsr mBhkc \"� l�hsd �mil"gic [ j3l"c [ mImBl ]¶w"]�{3]?t c3d"� ]?\ m _ e _ tk] �

� ��O�>PQ¸<�STH E�J�<�L�O)Q¸< VS¸H�3> � � l ]�}�]?� m w"]?� hsj \�rV\�w hk�­d ts] � ]?\ m r mBhkc \ _ rV\²}£] micVm rntst e _ c3�Zd"gic ��Zh ��]?w©} e }�rnw rnw �­h \ h � mBg r mBh {3]Frn\"w c3d ] g r mihsc \"rVt d"g r _ mih _ ] � o c ["\"w _ c \�± j [ g r mBhsc \ _ c \ mBg�c t h �rn}"� c tk[ m ]zt e ]?���i]?\ mih rVt)rV�¯rV\ h \ m ] j3g rVt d r g9m¯c x¾��[ g { h {Vrn} h t hkm�e3� ~ ¡ c3g ]�¢"r �­d tk]Vu"��]?] ¹ WV��� ÄK�À�

� l ]z�i] _ c \ _ ] d�m �#r g ] _ c \�� h w�] g ]zwµx®[ g�mBl ] g&h \�o§] _ mBhkc \"��  � �DrV\"w«  � ^ �¿�l ] g ]�rn���5] l r�{3] _ l"c ��]?\brªx g r � ]�� cVgi� h \ � l"h _ l �i[ g { h {nrV} h t hkm�e w"] d ]z\"w"� c \ �i] _ [ gihÂm�e u g ]?t h �

rV} h t hÂm�e u�rV\"w d ] g x cVgi� rV\ _ ]­r m�mBgih }"[ m ]?�­~®x c3g ]�¢"r �­d tk] � u � rV\ h x®]?� m r mihsc \"� c x½�i[ g { h {nrV} h t hÂm�e u��i] _ [ g�hkm�e urV\"w g ]?t h rV} h t hÂm�e ]�¢ h � m r m½� rV\ e w h »£] g ]?\ m tsr e ] g � c x�rV}"� mig r _ mBhkc \ � ��t mBl�c [ j3lZmBl ]���[ g { h {Vrn} h t hkm�e�c x�rV\]?\ m ] gid�gih ��] � r e w�] d ]?\"w c \ mBl ]�["\�w"] g t ePh \ j ��] _ [ gihkm�e rV\"w g ]zt h rn} h t hkm�e u mBl ]��i] _ [ gihÂm�e rV\"w g ]zt h rV} h t �hkm�e r m r d r g9mBh _ ["tsr g tsr e ] g#� r eµh \ m [ g \«w"] d ]?\"w mic � c3� ];]�¢ m ]?\ m¶c \ mBl ]F��[ g { h {Vrn} h t hkm�eyc x�r�t c �N] gt|r e ] g?� ¡ c3g ]�¢�r �Zd ts]nu mil ]Ã�i[ g { h {nrV} h t hkm�e c x�]�r _ l c x mBl ]y] hsj3lfm _ gihkmih _ rVtN\�r mBhsc \�rVt h \�x g rn� mBg [ _ m [ g ]z�_ c \"� h w"] g ]?wª} eÃmBl ] � aIa q � w"] d ]?\"w�� mBc � cV� ]D]�¢ m ]z\ m�c \ mBl ]D�i[ g { h {nrV} h t hkm�e rV\"w cVmBl ] g r mimigih }�[ m ]z�c x mBl ]D["\"w"] g t e§h \ j _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mBhsc \ h \�x g rV� mig [ _ m [ g ]?� � o hs�Zh tsr g t e u mBl ]D�i[ g { h {nrV} h t hÂm�e�c x rj3h {3]?\ _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mihsc \ h \�x g rV� mig [ _ m [ g ] � r eµm�ePd"h _ rVtst e w"] d ]?\"w mBc _ c \"� h w"] g rV}�ts]F]�¢ m ]?\ mc \ mBl ]��i[ g { h {nrV} h t hkm�e�c x mBl ]�]zts] _ mBg�h _ d�c �N] g rn\"w m ]?tk] _ c3�­� ["\ h _ r mBhkc \"� h \�x g rV� mig [ _ m [ g ]?� � q�\ d r g�m umBl�h � h �¶r _ c \��i]� '["]z\ _ ] c x mil ]�x r _ m¶mil r m¶mBl ]�w"]�±�\ hÂmBhsc \"�¶["�i]zw l ] g ]Zr g ]�~®\"] _ ]?�i�ir gih t e�� � c3� ]z� l r mc {3] g t|r d"d"h \ j �Rh \ d r g�m u hkm¯h �¯rVtk� c r g ] _ c3j \ hkmihsc \ c x mBl ]Dx r _ m&mBl r m ]?r _ l rV}�� mBg r _ m t|r e ] g¯l rV� hkm � c �&\�i] m¯c x g ]� '[ hkg ] � ]?\ m � mil r m&� ["� m }£] mBg rV\"��t|r m ]?w h \ mBc ��["} g ]� '[ hsg ] � ]?\ m ��r m t c �5] g t|r e ] g � �

º \"] c x mil ] d"gihk� r g�eZj3c rVtk� c x mil ] d"g ]z�i]z\ m � c3gi�­h � mic�h w"]z\ mBh x eZmBl ]#�½r e � h \ � l"h _ lÃmBl ]�{nr g�hsc ["�d"g�c3d ] g�mih ]?��rV\"w mBl ] hsg ]?\�x cVg _ h \ j�hk�­d ts] � ]?\ m r mBhkc \"�½w"] d ]z\"w c \ c \"]�rV\ cVmil ] g u�r m {nr gihkc ["�¯t|r e ] g � c xrV}"� mBg r _ mihsc \µrV\"w�r _ gic ���¯w h »£] g ]z\ m rn}"� mig r _ mBhsc \"�&r m&j3h {3]?\µt|r e ] g � �� l"h � g ] d�c3g�m¾h \D\ c �Nr e r m�m ] �Zd�m � mic }�]½r�w�]z±�\ hÂmBh {3]N��]?tÂx|� _ c \ m r h \�]?w mig ]?r mBh �i] c \F]z{V] g9ePmil"h \ j#mBl r m

\"]z]?w"� mBc }�] � \ c �&\ mBcZd"gic _ [ g ] g ��rV\"w�w"]z{V]?t c3d ] g � c x l"hkj3l t e �i[ g { h {nrV}"tk]D� e � m ] � � � p�r mil ] g u hkm r m �m ] �­d§m � mic�h w"]z\ mih x e rV\"w�["��] _ c \"� mBg [ _ mih {3]zt e � c3� ] c x mBl ]½x®["\"w�r � ]?\ m rVt _ c \ _ ] d�m � [ d�c \�� l"h _ l �i[ _ l� e � m ] � � _ rV\;}�] d�gic w"[ _ ]zw ��� ¢ m ]z\"� h {3]Nx®[ g9mBl ] g }"r _ �'j3gic [�\"w c \ _ c3�Zd [ m ] g � e � m ] ��mig ["� m � cVg�mBl�h \"]z�i�_ rn\�}�]Fx c ["\�w h \ � r mBhsc \�rVt p¯]z�i]�r g _ l4aNc ["\ _ h t g ] d�c3g�m �?u � � � � � � ��� � � �Z� � � � ¹  3^ Ä rn\"w mBl ] �Zc3g ]g ] _ ]z\ m � � � ��� � ��� � ����� � � � �� ¹ WV�'� ÄK� ~vo§]z]¶rVts� c ¹ �TX3� Ä x c3g r g ] _ ]?\ m¯� p a � m ["w e�c \ g ]z�i]�r g _ l \"]?]zw"� �¦�� � c {Vrnts[�rV}�ts]�{ c tk[ � ]?� c \ _ g9e§d§mBc3j3g r d"lfe � � g�c ts] h \ mBg [�� m � c3g�mil'e � e � m ] � ��rV\"w«\"] m � c3gi� �¶r g ] mBl ]� r mBhsc \�rVt�p&]?��]�r g _ l²aNc ["\ _ h t a p&q9o§q9o g ] d�c3g�m � � � � � � � � �� � � � � � � � � � � � � � � � �& � $ � � � � � � � � � �� � � ��� � ¹ �V� Ä rV\"w ´5g [ _ ]�o _ l \"] h ] g�� � � � � ��� ��� � � � � � � � � �� � ¹ WV�'  Äv� � g ]?rVt h � mih _ rV�i��]?��� � ]?\ m¶c x mBl ]gih � � � c x hs�Zd"gic3d ] g t e ] � }£]zw"w"]zw � mBg�c \ j _ g�ePd�mic©h ��x c ["\"w h \ o _ l \"] h ] g�� �F�i["}��i]� '["]z\ m } c§cV� ¹ WV�3� Ä u� � �� ��� � � ���� � ������� � � � ��� � � � � � � � � � ��� ��� � � ��� ����� � � � � �

Page 27: Practical Architectures for Survivable Systems and Networks (Phase

# � ��� � � >PJ)>'Q¸<�L H��f>�% ��E��4O�E�=�H S¸H®E£Jp&]?�i]?r g _ l ]�» cVg�m � l r�{3] m�ePd"h _ rVtkt e _ c \"� h w"] g ]?wÃ� hs�Zd ts] _ cV�­d�c � hÂmBhkc \"� c x �Zc w�["ts]z�?uP�i[ _ l rV�5["\ h w hsg ] _ �mBhkc \�rVt �i] gih rnt _ c \"\"] _ mBhkc \"� c3g�d ] gil r d � _ rntstÂ��rV\"w§� g ] m [ g \ª�i] � rV\ mih _ � � ~voP] _ mihsc \ � � � w h � _ [��i�i]z��� c3� ]c x mBl ]z�i] �À� ( c �N]�{3] g u mBl ]¶]�¢ h � mBh \ j�g ]z�i]�r g _ l«h �½x r g x gicV� g ]?rVt h � mih _ �� l ] _ c \ _ ] d§m c x ��� ��� ������� ��� �� � � � � � � � � � ¹ ^3�§� Ä [��i]?w l ] g ] h \ _ tk["w"]?� _ cV�­d�c � hÂmBhkc \ c x���["}"� e � m ] � �

� hkmil¶� [ m ["rVt3x®]?]zw"}�r _ � u l�h ] g r g _ l�h _ rnt3t|r e ] gih \ j&h \�� l"h _ l r _ c tkts] _ mBhkc \ c x �­c w"["tk]?�1x c3g�� ��rIt|r e ] g�mBl r m_ rn\Ã}£]�["�i]zwµ} e�l"hsj3l ] g tsr e ] g �IrV� h \ mil ] � gic {nrV}"t e oP] _ [ g ] º�d ] g r mih \ j o e � m ] � ~ � o º o � ¹ ��Xf^Pu"^n�f�§u^n�' 'u�^V�3X Ä u�t|r e ] gih \ j r _ l"h ]z{3]zw mil"gic [ j3l²d"gicVj3g r � �Zc w"[�t|r g�hkm�e ¹ �f� Ä u�rV\"w²\"] m � c3g�� ]?w _ c \�\"] _ mBhsc \"�h \f{ c tk{ h \ j _ t h ]z\ m ����] g {V] g r g _ l"hkm ] _ m [ g ]?�?u j r m ]��½r e �?u�["\ h w hsg ] _ mihsc \�rnt£rn\"wÃ} h w hsg ] _ mihsc \�rntR± g ]z�NrVtkts�½rn\"wj [�r g w"�zu�]?\ _ g�ePd�mBhkc \1uRrV\�w cVmil ] g _ c3�Zd£c \�]?\ m � � p&]?tk]z{nrV\ m r d"d"g�c r _ l ]z� h \ _ tk["w"] ¹ Wf §� Äv�q�\ mil"h � d"g�c�� ] _ m u¾�5] _ c \"� h w"] g�j ]?\�] g rnt h�� ]?w _ c3�Zd£c � hkmihsc \�rV� hkmDg ]?t|r m ]?� mBcµmBl ] _ c3�Zd�c �i]zw �i["}P�

� e � m ] � � ��¿ ]¶}�]?t h ]z{V] mBl r m¯mil"h �&r d"d"gic r _ l�mic _ c3�Zd£c � hkmihsc \ h � �­c3g ]¶r d"d"g�c3d"g�h r m ] mBc�mBl ] h \ m ]?\"w�]?wt|r gij ]���� _ rVts]�w h � migih }"[ m ]zw4rn\"w4\"] m � cVgi� ]zw r g _ l�hkm ] _ m [ g ]z� mil rV\ mil ] d"gihk� r g�h t eµmil ] cVg ] mih _ rVt _ c \ m ] � �d�c3g r g9e � c3gi�yc \ �­c w"]zt _ c3�Zd£c � hkmihsc \µrV\�w d�c t h _ e _ c3�Zd£c � hkmihsc \�~ rVt mil"c [ j3lÃmil r m � c3g��Ãh �&t cVj3h _ rVtst e�i[�}"�i[ � ]?w�["\"w"] gImBl ] d"g ]?�i]z\ m r d"d�gic r _ l����

# � ��� � � >PJ)>'Q¸<�L H��f>�% �Ã>'O�>PJ %�>PJ 3>q�\ �T�3 n�"u � r g \�rV� ¹ ^3 V� Ä _ l r g r _ m ] gih�� ]?w�r&{Vr gih ] m�e¶c x %�>'O�>§J'%)= �)O�E�J g ]?tsr mBhkc \"� � ��\ hs�Zd�c3g�m rV\ m �i[ _ lg ]zt|r mihsc \ h � � r g \"rV� � � %)>'O�>PJ'% = ��O�E�J �¼ERQDH®ST=�3ERQ¸Q�>�VS¸J�>P=�=

�� l ] g ]?} e r j3h {3]?\ _ c3�Zd£c \�]?\ m�h � �Br h w

mBc w"] d ]z\"w;[ d£c \DrV\ cVmBl ] g _ c3�Zd£c \"]?\ m�h \ mil ] �i]?\��i] mBl r m)h x mil ] t|r m�m ] g _ c3�Zd�c \"]?\ m w c ]?��\ cVm�� ]?] m�hkm �g ]� '[ hsg ] � ]?\ m �zu mil ]?\ mBl ]Dx c3g�� ] g½� r e \ cVm¯� ]z] m&hÂm � g ]� P[ hsg ] � ]z\ m � �5� ]z[ � rV\"\ ¹ ^3�P� Ä�l rV� g ]z{ h � hkm ]zwmBl ]�\ cnmBhsc \ c x1w"] d ]z\"w"]?\ _ ]Vu � r �'h \ j rDw h � mih \ _ mBhsc \Z}�] m �5]?]z\ mBl ] � r g \�rn� g ]?t|r mBhsc \ %�>'O�>PJ %)= ��O�E�J�¼ERQ)3E�Q¸Q¸>�VS¸J�>§=?= rn\"w�r j ]z\"] g rVt h�� ]zwZ��]?\"��] c x�w"] d ]z\"w"]z\ _ ] h \F� l"h _ l­j3g ]�r m ] g mig ["� m � c3g9mBl"h \"]?��� _ rV\}�] r _ l"h ]z{V]?w w"]z� d"hÂm ] mBl ] d"g ]z�i]?\ _ ] c x½ts]?��� mig ["� m � c3g9mBlfe _ c3�Zd£c \"]?\ m �zu mBl ] g ]z} e r�{ cVh w h \ j�l rT{ h \ jmBc w"] d ]?\"w _ c3�­d ts] m ]?t e c \ _ c3�Zd£c \"]?\ m � c x&["\ � \ c �&\ c3g ["\ _ ] g9m r h \ mBg ["� m � c3g�mil"h \�]?�i� � � c r�{ c3h wl r�{ h \ jymBc �Br e ��w"] d ]z\"w"�D[ d�c \ h \ mil ]Z�i]?\��i] c x j ]z\"] g rVt h�� ]?w�w"] d ]z\"w"]?\ _ ] � u¾�N]�rV}"} g ]z{ h r m ] mBl r mj ]z\"] g rVt h�� ]?w g ]?t|r mBhsc \yrV�I� hk�­d t e %�>'O�>§J'%)=­E�J �� l ]�x c tst c � h \ j ]?\'[ � ] g r mBhkc \ j3h {3]z�¾{nr gihkc ["� d r g rnw hsj3� ��["\"w"] g � l"h _ lFmBg ["� m � c3g�mil"h \�]?�i� _ rV\�r _ m [P�

rVtkt e }�]#]z\ l rV\ _ ]?w1u d"gic { h w h \ j ]�¢�r �Zd ts]z� c x l�c � mil ] j ]?\"] g rVt h�� ]zw�w"] d ]z\"w"]z\ _ ] g ]?t|r mBhsc \ %�>'O�>§J'%)=�@E�J w h »£] g �1x gic3� mBl ] _ c \f{3]z\ mihsc \"rVt %)>'O�>PJ %)=�@ �)O�E�J g ]zt|r mihsc \ � q�\D]�r _ l�c x mBl ]?�i] _ rV�i]z�?u mil ] g ]z�i["t mBh \ jmBg ["� m � c3g9mBl"h \"]?��� m ]z\"w"� mBc }£] j3g ]?r m ] g�mil rV\ mBl r m�c x mBl ] _ c \"� mihkm [�]?\ m _ c3�Zd£c \�]?\ m � � � l ]#t h � m h � �i[ g �d"g�h � h \ j t e t c \ j uPrV\"w � r e�l ]zt d­mic�h tstk["� mig r m ] mBl ] d£c �5] gNc x mBl ]#\ cVmihsc \ c x j ]?\"] g rVt h�� ]?wZw"] d ]?\"w�]?\ _ ] �~ ��t mil"c [ j3l«d r g�mih _ ["t|r g�� ] _ l rV\ h � � � � r e x rVtkt h \ mic � ["t mBhkd ts] m�ePd ]z�?u mBl ]?�i] m�ePd ]?�¶r g ] h \ m ]z\"w"]zw micg ] d"g ]z�i]z\ m�mBl ]Dw h {3] g �i]D\�r m [ g ] c x � ] _ l rV\ h � � � l rT{ h \ j�mBl ] _ l r g r _ m ] gih � mih _ � c x j ]?\�] g rnt h�� ]?wyw"] d ]z\§�w"]z\ _ ] �À�

� � � l ]F["�i] c x ] gig�c3g � _ c3g�g ] _ mBh \ j _ c w"]z�Z~ ] �Áj"� u ¹ �¸^VW Ä �&mBl r m _ rV\©]z\�rV}"tk] _ c3g�g ] _ m _ c3�­� ["\ h _ r mBhkc \"�w�]?� d�hkm ] _ ] g9m r h \ mic ts] g rV}�ts] d r mim ] g \"� c x£] g�gic3g ��~ ] �·j"� u g rV\"w c3� u3rV� eP�Z� ] mBgih _ rV� h \�} hÂm �¼w gic3d�d"h \ jc \"t e uI}"[ g � m�e u c3g�cnmBl ] g � h ��] _ cVgig ]zt|r m ]?w � u h \+}�t c _ � _ c3�­� ["\ h _ r mBhkc \"� c3g ]z{3]z\ h \+{nr g�h rV}"tk]��tk]?\ jnmBl c3g �i]� '["]z\ mBh rnt½]?\ _ c w h \ j � _ l ] � ]?�zuNrV�;t c \ j rV��rV\ e g ]� '[ hkg ]?w g ]?w"["\�w�rV\ _ e w c ]?�F\ cnm_ rV["��] mil ]Nr�{nr h t|rV}"tk] _ l rV\�\"]?t _ r d r _ hÂm�e�mBc }£]�]�¢ _ ]z]?w"]zwµ~®x c tkt c � h \ j½mBl ] j [ h w�rV\ _ ] c x�o l rV\�\ c \ � �h \�x c3g�� r mihsc \ mBl ] c3g�e�� uRrV\"w h \µr gihÂmBl"� ] mih _ c3d ] g r mihsc \��D~ ] �·j"� u ¹ ^n�3� Ä|�

Page 28: Practical Architectures for Survivable Systems and Networks (Phase

^ � � l ]½]�r g t e � c3gi��c x£Y c3l \F{ c \ � ]z[ � rn\"\ ¹ WV�V� Ä rV\"w c x � w � cPc3g ]½rV\"w a t|rn["w"]Io l rV\"\ c \ ¹ ^3^V^ Ä u� l�c � l"c �5]?w l"c � g ]?t h rV}�ts]¶�i["}�� e � m ] � � h \ j ]z\"] g rVt½~ { c \ � ]?[ � rV\"\ � rV\"w g ]?t h rV}"tk] g ]?tsr e _ hsg �_ [ hkm � h \ d r g�mBh _ ["tsr g ~ � c§c3g ]��o l rV\"\ c \ � _ rV\ }�]Z}"[ h t mDc [ mFc x½["\ g ]?t h rV}"tk] _ c3�Zd£c \"]?\ m � � rn�t c \ j rV� mil ] d"gic }�rV} h t hkm�e�c x¯x r h ts[ g ] c x�]�r _ l _ cV�­d�c \"]z\ m�h ��\ cVm�d"g ] _ h �i]zt e c \"]�� l rVtkx¯rn\"w+rn�t c \ j rV� mBl"c �i] d"gic }"rV} h t hkmih ]?�Nr g ] h \�w"] d ]?\"w�]?\ m x g�c3��c \"]�rV\ cnmBl ] g�� rVts� c�g ]?tk]z{nrV\ m�h � mBl ]Z�T�3�VXd r d ] g�c x � rV["t ´ r g rV\ ¹ ^3  ÄRc \ � r �'h \ j¶g ]zt h rV}"ts] _ c3�Z� ["\ h _ r mBhsc \"� w"]z� d"hÂm ]&["\ g ]?t h rV}"tk]½\"] m � c3g��\ c w"]z�?u"� l"h _ l �NrV� h \§³�["]?\ mih rVt h \ mBl ]¶]�r g t e w�r e � c x mBl ]D�#p � �#\"] m��

W � oP]?tkx|�¼� e \ _ l"g�c \ h��?h \ j«m ] _ l \ h '["]z� mBl r m�g ]?��["t m�h \ g r d"h w g ]?� e \ _ l�gic \ h�� r mihsc \ x c tkt c � h \ j \ c \ mic tÂ�] g r m ]?wª] gig�c3g � mBl r m _ rn["�i]Ft c �i� c x�� e \ _ l"gic \ h�� r mBhsc \1u h \ _ tk["w h \ j­h \ mBgih \"� h _ g ]?� e \ _ l"gic \ h�� rV} h t hkm�ec x��i]� '["]?\ mBh rVtst e � mig ]�r � ]zw _ c w"]?� � } e rVw"w h \ j ]�¢ d t h _ hÂm x g r �Zh \ j } hÂm �zu c3g rVw"w h \ j4g ]?w"["\P�w"rV\ _ e�mic;d"g�c { h w"] hs�Zd t h _ hÂm � e \ _ l�gic \ h�� r mihsc \�rV� h \ _ c3�Z� r¸�¼x g ]z] _ c w"]?�zu cVg � hÂmBl"c [ m5l rT{ h \ jDmicrnw"w«rn\ eyg ]?w"[�\"w�rV\ _ eµh \ _ ] g�m r h \y{Vr gih rn}"ts]���ts]z\ jVmil rV\"wµ�i]� '["]z\ mBh rnt _ c w"]z� ¹ ^n�fXPu£^n�"�Vu�^��'^ Ä ~Krn���]?tÂx|� g ]z� e \ _ l"g�c \ h��?h \ j«d"g�c3d ] g�mih ]?� c x _ ] g9m r h \ {nr gih rV}"tk]���tk]?\ jnmBl _ c w"]z� ¹ �TWf� Ä rV\"w h \�x c3g�� r mBhsc \§�t c �i��ts]z�i� ¹ �TW3� Ä ��]� '["]z\ mih rVtI]z\ _ c w h \ j � e � m ] � � � � rV���N]ztstIrn� cnmBl ] g �i]?tÂx|��� m rV} h t h�� r mihsc \ m ] _ l �\ h '["]?��~®] �·j"� u ¹ �f  Ä �

� � p c }"[�� m � e \ _ l�gic \ h�� r mihsc \ rVt j3c3gihÂmBl"� �?uI��[ _ l rn� l"h ] g r g _ l"h _ rVtst e+d"g�hsc3g�hkmih�� ]zwbt c _ �'h \ j � mBg r m ]��jVh ]?� ¹ �n� Ä u m � c � d"l rV��] _ c3�Z�­hÂmB� ]?\ m �zu£\ c \'}"t c _ �'h \ j r mBc3�Zh _�_ c3�Z�­hÂmB� ]?\ m � ¹ W��¸� Ä u�rV\"wªx®[�tk±�tktÂ�� ]?\ m¶mBg rV\"�ir _ mihsc \"� ¹ ^VXf� Ä ��[ _ l rV�¶x r hkg ��]�¢ _ l rV\ j ] d"g�cVmBc _ c ts� j [�r g rV\ m ]z] h \ jµmil r mDd r eP� ]z\ m;h �� rVw"] h x rV\"w c \"t e�h x j3cPc w�� l r�{3]D}£]z]?\µw"]?t h {3] g ]zw

� � � g rnw hkmihsc \�rntNx rV["t m � mic ts] g rV\ _ ]yrVt j3c3gihÂmBl"� ��rV\"w�� e � m ] � _ c \ _ ] d§m � mil r m _ rV\ mic ts] g r m ] _ ] g9m r h \� d ] _ h ± _ m�ePd ]z� c x _ c3�Zd£c \"]?\ mÃc3g �i["}"� e � m ] � x r h tk[ g ]z� rV�yr g ]?��["t mÃc x _ c \"� mBg [ _ mBh {3]©["��] c xg ]?w"[�\"w�rV\ _ e ¹ �T�§u��VX§u ���f�Pu �T�V�§u�^nX3��u�^V^3�§u1WV�3� Ä � rVt mil"c [ j3l x r h tk[ g ]z�#}�] e3c \"w mil ] _ c {V] g r j ]c x mil ]�x rV["t mNmBc tk] g rn\ _ ] � r eÃg ]z�i["t m&h \y["\"� d ] _ h ±"]?w�x r h ts[ g ] �Zc w�]?�

� � ��t m ] g \"r mBh {3]�� _ c3�Zd [ m r mBhkc \ r g _ l�hkm ] _ m [ g rVt�� mig [ _ m [ g ]?�?u&� l"h _ l _ rV\ r _ l"h ]�{3]©�Br mBh �9x r _ mic3g�e }"[ m\ c \"]� '[ h {nrVts]z\ m�g ]?��["t m �N~ � hkmilDd�c ��� h }�t e w�] j3g rVw"]?w d ] g x cVgi� rV\ _ ] � u�w"]?� d"hkm ]�x r h tk[ g ]z� c x l r g w§�½r g ]rn\"w � c x m �Nr g ] _ c3�Zd�c \"]?\ m ��rn\"w x r h ts[ g ] �Zc w"]z� mBl r m ]�¢ _ ]?]zw d t|rn\"\"]?w²x rV["t m _ c {3] g r j ]Vu)�i[ _ lrn� mBl ] � ]�� _ rV� m ts]�p¯] _ c {3] g�e�´ t c _ � �&r d"d�gic r _ l ¹ �¸ §u��T�Pu��TWV� Ä

  � ��t m ] g \"r mBh {3]�� gic [ mBh \ j � _ l ] � ]?� h \ d r _ � ] m �¼��� hkm _ l ]?wZ\"] m � c3g�� �?uf� l"h _ l _ rV\�r mim r h \ j3cPc w d ] g x c3g �� rV\ _ ]¶rV\"wµ]z{V]?\ m [�rnt _ c3�­� ["\ h _ r mBhkc \"�½w�]?� d�hkm ] � r ��c3gIc [ m r j ]z�¯r �­c \ j�h \ m ] gi� ]?w h r m ]�\ c w"]z�rn\"wyw h � m [ g }�rV\ _ ]?� h \ _ c3�Z� ["\ h _ r mBhsc \"� � ]?w h rµ~KrV� h \ mil ]¶��p � ��\"] m¯gic [ mBh \ j�d"gicVmic _ c ts� �

� ��´�e � rV\ mBh \"];x rV["t m � mBc tk] g rn\ m � e � m ] � � mil r m _ rV\ª� hkmil � m rV\"w ´5e � rn\ mih \"]�x rV["t m#�­c w"]z� ¹ �T�V�"u�W3WV��uWn�'^ Ä u�� l ] g ]?} e �i[ _?_ ]z�i�9x®["t c3d ] g r mihsc \ h � d£c �i� h }"ts]#w"]?� d"hkm ] mil ]Dr g } hkmBg r g�e rV\"w _ c3�­d ts] m ]?t e ["\P�d�g ]?w h _ m rV}"tk]�}£] l r�{ hsc3g ~ � rnt h _ hsc [��it eFc3g r _?_ h w"]z\ m rVtkt e���c x [ dÃmBc � c3� ] g r mihsc�c x hÂm � _ c3�­d�c \"]z\ m��["}"� e � m ] � �«~ ] �Áj"� u � c [ m�c x�W ��� � � u�� hÂmBl \ c rV�i��[ �Zd�mBhkc \"� g ] j r g w h \ j²h \"w h { h w"[�rVt�x r h tk[ g ]�Zc w"]?� c x mBl ] _ c3�Zd£c \�]?\ m �i["}"� e � m ] � �

� ��´�e � rV\ mBh \"]¶\"] m � c3gi� �¼t|r e ] g�d"g�cVmBc _ c ts� ¹ ^V�f� Ä�TX ��� \ _ g�ePd�mihsc \²r d�d t h ]?w mic rV\ c3d ]?\ mig rV\�� �Zh �i� hsc \ � ]zw h [ � c3g � mic3g r j ] � ]zw h [ � mil r m#h ��]?rV� h t e

h \ m ] g _ ] d�m ]zw cVg½�­c \ hkmic3g ]zw1uP� l ] g ]z} e mBl ]�]z\ _ g9ePd�m ]zwµx c3g�� h �½� hkj \ h ± _ rV\ m t eZ�­cVg ] h \"� _ g [ m rV}"tk]

��

Page 29: Practical Architectures for Survivable Systems and Networks (Phase

�3� � ¬¯�i] c x h \ m ] jVgihkm�e _ l ] _ � �?u���[ _ l rV� _ g9ePd�mBc3jVg r d"l�h _&_ l ] _ � ��[ � �&rn\"w d�gicPc x|� _ r gig9e§h \ j _ c w"] ¹ ^VW3� Ä u} cVmil c x½� l"h _ l _ rV\ ]z\�rV}"tk] mil ] w"] m ] _ mBhkc \ c x&["\�]�¢ d ] _ m ]?w rVt m ] g r mBhkc \"� mBc � e � m ] � � cVg w�r m rrn\"w l"h \"w�] gImBl ] m r �­d ] g�h \ j�c x¾w�r m r�rV\"w d"g�c3j3g r � �

�¸^ � � h _ rnt h � ��x r hsg�d [�}"t h _ � � ] e _ g9ePd�mBc3jVg r d"l�h _ � _ l ] � ]?� ¹ ^VX3� Ä u h \+� l"h _ l w h »£] g ]?\ m d r g�mih ]?� � ["� m_ c§cVd ] g r m ]½� hkmBl�mil ]&� hs� ["t m rV\"] c ["� d"g ]?�i]z\ m r mihsc \ c x � ["t mihsd tk] � ] e � � rntst c � h \ j _ g9ePd�mBc3jVg r d"l �h _ rVtkt e }�rV��]?w c3d ] g r mBhsc \"� mBc�g ]� '[ hsg ] mil ] d"g ]z�i]z\ _ ] c x � ["t mihsd tk]�rV[ mil"c3g�hkmBh ]?�

�TW � � l�g ]?� l"c tkw � ["t mBhs� ] e � _ g�ePd�mic3j3g r d"lfe � _ l ] � ]?�zu h \�� l�h _ l r m ts]?rV� m � c [ m¾c x �� ] e � r g ] g ]� '[ hsg ]?w

~ x c3g _ c \f{3]?\ mihsc \�rnt�� eP�­� ] migih _ � � ] e w"] _ g�ePd�mBhkc \1u c3g x c3g rV[ mBl ]?\ mBh _ r mihsc \1u cVg x c3g ]?� _ g�c �5]?w g ]��migih ]z{nrVt � � x c3g ]�¢�r �Zd ts]nu"r ´5e � rV\ mBh \�]�w hsj3hÂm rVt ��� hsj \�r m [ g ]¯� e � m ] � ¹ ��� Ä rn\"wyr ´5e � rV\ mih \"] � ] e �]z� _ gic � � e � m ] � ¹ W��T� Ä1mBl r m _ rV\yx®["\ _ mBhkc \y�i[ _z_ ]?����x®["tkt e w�]?� d�hkm ] mil ] d"g ]z�i]?\ _ ] c x¾� c3� ] d r g�mih ]z�mil r m5� r e }�]#["\ mBg ["� m � c3g9mBlfeÃc3g ["\�r�{nr h tsrV}"ts]nu'rV�5�5]?tkt�rn�½r;� hsj \�r m [ g ]#� _ l ] � ] mBl r m _ rn\�x®["\ _ �mihsc \ _ c3gig ] _ m t e w"]?� d"hkm ] mil ] d"g ]z�i]z\ _ ] c x � rVt h _ hkc ["� {3] gih ±"] g � ¹ ^V�3� Ä

��� ��´�e � rV\ mBh \"]��¼� m�e ts]�rn[ mBl ]z\ mBh _ r mBhkc \ d�gicVmic _ c ts� mBl r m _ rV\­� c3g��­d�gic3d ] g t e w"]?� d"hkm ]�["\ mBg ["� m � c3g9mBlfe[��i] g � c3g�� � m r mBhsc \"�?u _ c3�Zd"gic3�Zh ��]?w�rV[ mBl ]?\ mBh _ r mihsc \­�i] g {3] g �?u�rV\�w cVmBl ] g '["]z� mBhkc \�rV}�ts] _ c3�Zd£c �\�]?\ m �;~ ��]?] aNl r d�m ] g   �

�¸� � aNc \"� mig [ _ mBh {V] ["��] c x � ] g \�]?ts�;rV\"w � mBg [�� m ]zw � _ c3�­d [ mBh \ j }�rn�i]?� mBc r _ l"h ]�{3] \ c \"�i["}f{V] g�mih }"tk]r d"d t h _ r mihsc \ d"gicVd ] g�mBh ]?�zuf�i[ _ l rV� h \ZoP]�r �#h ]z�¶uf� l"h _ l w"] �Zc \"� mBg r m ]?w l"c �br � ["t mih tk]z{3]ztÂ�¼�i] _ [ g ]w"r m rV}"rV�i] � rV\�r j ] � ]z\ m � e � m ] � _ rV\�}£] hk�­d tk] � ]?\ m ]zw c \ mBc3dµc x�r � ["t mBh ts]z{V]?t ���i] _ [ g ] � ] g \"]zt� � hkmBl rV}�� c tk[ m ]zt e \ cZg ]� '[ hkg ] � ]?\ m x c3gI� ["t mih ts]�{3]ztÂ����] _ [ gihÂm�eZmig ["� m � cVg�mBl�h \"]z�i� h \ mBl ] º�g r _ ts]w"r m rV}"rV�i] � rV\�r j ] � ]z\ m � e � m ] �µ� ¹ �3�§u����3��u��T�3X Ä ~ � l"h � h � mBl ]¯\ cVmihsc \ c x£}�rVtsrV\ _ ]?w­rV�i��[ g rV\ _ ] �¦�

�T� � � ["t mih t|r m ] g rVt � ] _ l rV\ h � � �&]z\�x c3g _ h \ jZd�c t h _ h ]z� c x � [ m ["rVt��i["� d"h _ hsc \�uR� hÂmBlymBl ]�rV} h t hÂm�e­mic�c3d �] g r m ] _ c3g�g ] _ m t e w"]z� d"hÂm ]DrZtsr _ ��c x mig ["� m r �­c \ j�mil ]�{nr gihkc ["� d r g�mBh ]?� ¹ Wf�§� Ä

�¸  � q�\ m ] gid�c � hkmBhkc \ c x mBg ["� m � c3g�milfe ± g ]��½rVtkts�¶rV\�w j [�r g w�� mBl r m¶� ]?w h r m ]F}£] m �N]z]?\ g ] j3hkc \"� c xN["\P�]� '[�rVt mig ["� m � cVg�mBl�h \"]z�i� � x cVg ]�¢�r �Zd tk]VuP]?\"��[ gih \ jFmBl r m �i]z\"� hÂmBh {3] h \�x c3gi� r mihsc \�w c ]?�½\ cVm tk]�r �c [ m rV\�w mBl r m � g�c�� rV\ l"c3g �i]z�&rV\"w cVmil ] g½l r gi� x®["t�]z»£] _ m �Iw c \ cVm �i\"]?r ��h \1u�w�]?� d�hkm ] mBl ] d"g ]?��]z\ _ ] c x ["\ mBg ["� m � c3g9mBlfe ��["}"� e � m ] � � c3gI� [ m [�rVtst e ��["� d�h _ hkc ["�¯rVw�{V] g �Br g�h ]?�

�T� � ¬¯�i] c x g ["\§� mBhk� ] _ l ] _ � � mBc�d"g ]�{3]?\ mDc3g�� ]zw h r m ]�]�¢§] _ [ mBhsc \ h \ '["]z� mBhkc \�rV}�ts] _ hsg _ [ � � m rV\ _ ]z�~®] �·j"� u5] � }£]zw"w"]zw h \ mil ]y}�rV��] d�gic3j3g r � � c3g�h \ r d�d t h _ r mihsc \ d�gic3j3g r � �?u�rV� h \ mil ] _ rV��]?� c x} c ["\�w"� _ l ] _ � ��rn\"w _ c \"� h � m ]?\ _ e _ l ] _ � � �

�T� � ��w"w hÂmBhsc \ c x�� g r d�d ] g �²~ � hkmBl�c [ m­�­c w h x ePh \ jªmBl ]�� c [ g _ ] c3g­c } � ] _ m _ c w"] c x mil ]�� g r d"d ]?w�Zc w"["ts] � u mic ]?\ l rn\ _ ]Z�i[ g { h {nrV} h t hkm�e u1�i] _ [ g�hkm�e u cVg�g ]?t h rV} h t hÂm�e u c3g�cVmBl ] g � h �i] _ cV�­d ]?\"�ir m ]Fx cVgw�]z± _ h ]?\ m _ c3�Zd£c \"]?\ m ��� ��[ _ l rV�#rVw"w h \ j r � mBg ["� m ]?w d r mBl �ZmBc rV\ h \ l ] g ]z\ m t e ["\ mig ["� m � c3g �milfe � e � m ] � u§]?\�rn}"t h \ j��Zc \ hÂmBc3g�h \ j¶c x cVmBl ] g � h �i]�["\ �Zc \ hkmic3g rn}"ts]Ix®["\ _ mBhkc \�rVt hkm�e u cVg5d"g�c { h w h \ j_ c3�Zd r mBh } h t hkm�e�c x)� g r d"d ]zw�tk] j r _ e d�gic3j3g r � �½� hkmBlycVmil ] g&d"g�c3j3g r � �

^VX � º } � ] _ m � c3g�h ]?\ m ]?w1u�w c3� r h \P��]?\§x c3g _ ] � ]?\ m u�rV\"w�r _z_ ]?���9� _ c \ mBg�c t m ] _ l \ h '["]z� mBl r m ]z»£] _ mih {V]?t e¶� ]��w h r m ] c3g�cVmil ] g � h �i] �­c w h x e;mBl ] h \ m ]z\ mNc x _ ] g�m r h \�r mim ] �Zd�m ]zw c3d ] g r mBhsc \"�?uPw"] d ]?\�w h \ j;c \ mBl ]]�¢§] _ [ mBhsc \ _ c \ m ]�¢ m ¹ �TXf^§u�^V�3X§u"Wf�§� Ä � x c3g ]�¢�r �Zd tk]Vu mil ] _ c \�±"\"]?wµ]?\f{ hsg�c \ � ]?\ m&c x mBl ]DY3r�{nr�#hsg9m [�rVt � r _ l"h \"] ¹ �3�?��u��3�T� Ä rV\"w g ]?tsr m ]zw4� cVgi��c \4x c3g�� rVt � d ] _ h ± _ r mihsc \ ¹ �f Pu5�3�T^ Ä x cVg�mBl ]rn\�rVt e � h � c x mBl ]¶��] _ [ gihkm�e c x¾��[ _ l ]z\f{ hkgic \ � ]z\ m �

Å�Å

Page 30: Practical Architectures for Survivable Systems and Networks (Phase

^§� � ¬¯�i] c x g ]?rVtÂ� mBhs� ]yrV\�rnt e � h � m ] _ l \ h '["]?� ��[ _ l rV� rn\ c3� rVt e rn\"w �Zh �i[��i]µw"] m ] _ mihsc \ mBc w h r j �\ c �i]�t h {V] mil"g ]?r m �#rV\"w g ]?� d£c \�w©r _?_ c3g w h \ j t e u _ r d rV}"tk] c x�w e \"r �­h _ rVtkt e rVt m ] gih \ j � e � m ] � rn\"w\�] m � c3gi� _ c \�± j [ g r mihsc \"�I}"rV�i]zw c \ d ] g _ ] h {3]?w mBl"g ]�r m ��~ ] �·j"� u ¹ WVXV��uRW3X3� Ä|�

� r _ l+c x mBl ]z�i] d r g rnw hsj3� ��w"] �Zc \"� mBg r m ]z� m ] _ l \ h '["]?��� l ] g ]z} e+mBg ["� m � c3g9mBl"h \"]?��� _ rn\b}£]µ]?\P�l rV\ _ ]?w4rV} c {V]­� l r m _ rV\4}�]�]�¢ d ] _ m ]?w c x mBl ] _ c \"� mihkm ["]?\ m �i["}"� e � m ] � � c3g�mBg rn\"� �Zh ��� hsc \ � ]?w h r �´5eZj ]z\"] g rVt h��?h \ jDmil ]#\ cnmBhsc \"� c x�w"] d ]?\�w"]?\ _ ]¶rV\"w mig ["� m � cVg�mBl�h \"]z�i�?u"rV\"w � ["w h _ hkc ["��["�i] c x�� cV� ] c xmBl ]?�i] m ] _ l \ h '["]z�?u��5]��i]z] ��mBcFd�gic { h w"]#r�["\ h x ePh \ j x g r � ]z� c3gi� x cVg�mil ]�w"]�{3]?t c3d"� ]?\ m½c x��i[ g { h {nrV}"tk]� e � m ] � � �¨�] d ]?\�w"]?\ _ ] c \ _ c3�­d�c \"]z\ m ��rV\"w h \�x cVgi� r mBhkc \ c x�["\ � \ c �&\ mig ["� m � c3g9mBl"h \"]?��� h � r d r g�mBh _ ["tsr g t e

�i] gihkc ["� d£cnm ]?\ mih rVt d�gic }"tk] �µ� ~voP]?]�o§] _ mBhkc \"��^ � � � �DrV\�wª^ � � � ^ �¦�¨�] d ]?\�w�rV}"tk] _ t c _ � �F~ ´5e � rV\ mBh \�] c3g�cVmBl ] g � h �i] �&d"gic { h w�];r d r g�mih _ [�t|r g t e h \ m ] g ]?� mBh \ j _ l rVtkts]z\ j ] �

� h \ _ c ts\�u5p&["� l } e uIrV\"w cVmBl ] g � ¹ �T��� Ľd"gic { h w"]µrV\ ]?tk] j rn\ m w"] m r h ts]zw ]�¢�r �Zd ts] c x j ]?\�] g rnt h�� ]?w w"]��d ]?\"w"]z\ _ ] � � l ] e l rT{V]yrV\�rVt e � ]?w r mBl"g ]?]��¼t|r e ] g ]zw �­c w"]?t _ c \"� h � mBh \ jªc x�~� � _ t c _ � � e \ _ l"gic \ h�� r��mBhkc \ ¹ WVWf^ Ä u"~K^ ��´5e � rV\ mih \"]�r j3g ]?] � ]z\ m ¹ �¸ V��uf���3X Ä uVrn\"w ~ W � w h r j \ c � h ��rV\�w g ] �Zc {nrVt c x§x rV[�t m�e _ c3�Zd£c �\"]z\ m � ¹ �T�3X Äv� � l ] e rVtk� c ]�¢ l"h } hkm x c3g�� rVtn{3] g�h ± _ r mBhkc \"��x c3g r&{nr g�h ] m�e�c x lfe } g�h wFrnt j3c3g�hkmil"� � ¹ �T�VX ÄfmBl r m_ rn\ jVg ]�r m t e�h \ _ g ]?rV�i] mil ] _ c {3] g r j ] c x �Zh ��}£] l r�{ h \ j _ cV�­d�c \"]z\ m � � � l�h � mBl�g ]?]���tsr e ] g ]?w h \ m ] j3g r mihsc \c x ��] d r g r m ] �Zc w"]?tk��rV\"w d�gicPc x®� h � c x _ c \"� h w"] g rV}"ts] d"g r _ mBh _ rVt h \ m ] g ]z� m u1rV���N]ztst¾rV� h tkts["� mBg r mBh {3] c xx c3g ]zx gic \ m [��i]?� c x)x c3gi� rVt � ] mil"c w"� ��#\Ã]�¢�r �­d ts] c x j ]?\"] g rVt h�� ]?w w"] d ]z\"w"]z\ _ ] g ]zt|r mih \ jDmBc _ t c _ � w gih x mNh � j3h {V]?\Ã} e ¡ ] m � ] g rV\"w aNg�h �9�

mBh rV\ ¹ �TXV� Äfh \�w"]z{V]?t c3d"h \ j x rn["t m � mBc ts] g rV\ m1l r g w��Nr g ] _ t c _ � � c [ m�c x _ c3�Z� ] g _ h rVt c »�� mBl ]���� l ]?tÂx1~ aIº � o �_ cV�­d�c \"]z\ m �?u�r m tk]�rV� m#c \�] c x � l"h _ l©h ��r � � o g ] _ ] h {3] gz� � x cVgi� rVt)rV\�rVt e � h � c x�r mihs� ]�� mBgihkj3j ] g ]?w_ t c _ � � e \ _ l"g�c \ h�� r mBhkc \µr d"d"g�c r _ lµh � j3h {3]z\�} e ¹ ^V�3� ÄK�� l ]�}�rn� h _ r d"d"g�c r _ lyc x mBl"h � d"g�c�� ] _ m _ c \"� h w"] g �½� hÂmBl"h \Ãr _ c3�Z�Zc \�x g r � ]�� c3g��­� rV\ e w h »£] g ]z\ m

j ]z\"] g rVt h�� ]?wP��w"] d ]z\"w"]?\ _ ] � ] _ l rV\ h � � � mil r m r g ] _ r d rV}"tk] c x1]z\ l rV\ _ h \ jDmig ["� m � c3g9mBl"h \"]?���?u§]?\�rV}�t h \ jmBl ] g ]?�i[�t mBh \ j x®["\ _ mBhsc \�rVt hÂm�e�mic }�] h \ l ] g ]z\ m t ey�Zc3g ] mig ["� m � c3g9mBlfeymBl rn\ cVmil ] g � h �i] �Zhsj3lfm }�]D�Nr g �g rn\ m ]?wµ} e _ c \"� h w"] g r mihsc \ c x c \�t eÃhÂm � _ c \"� mihkm [�]?\ m _ c3�Zd£c \"]?\ m � �

# � ��� �&��Q"��H ��<�� HKL H®S ! C­H S¸: � >PJ)>'Q¸<�L H��f>�% �Ã>'O�>PJ %�>PJ 3>¬�t mBhk� r m ]?t e u c {3] g rVtst � e � m ] � ��[ g { h {nrV} h t hÂm�ey� r e w"] d ]?\�w c \ ~ h \ mil ]F��]?\"��] c x j ]?\"] g rVt h�� ]zwªw"] d ]z\§�w"]z\ _ ]I\ cnm ]?wFrV} c {V] �)mil ]½�i] _ [ g�hkm�e u h \ m ] j3gihÂm�e u g ]?t h rV} h t hÂm�e u¸r�{nr h tsrV} h t hkm�e uTrV\"w d ] g x c3gi� rV\ _ ] _ l r g r _ m ] g �h � mBh _ � c x _ ] g9m r h \ _ g�hkmBh _ rVt d�c3g�mihsc \�� c x mBl ]�["\"w"] g t e§h \ j _ c3�­d [ m ] g � _ c3�Z� ["\ h _ r mihsc \ h \�x g rV� mig [ _ m [ g ]?� �q�\ mBl�h � g ] d�c3g�m u c [ g \ cVmihsc \ c x �i[ g { h {nrV} h t hkm�e ]�¢ d t h _ hkm t eÃh \ _ tk["w"]z� mBl"h � _ c \ m ]�¢ m¶c x j ]?\"] g rVt h�� ]zwªw"]��d ]?\"w"]z\ _ ] �

� � � ����� � � � ��� � ��� � � � � � � � ��� � ��� � � � � � � �Ic3g � ��� � ��� � � � ~ ��]?]«o§] _ mBhsc \ � � W²rV\"w ¹ ^3�VXPu�^3�§�Vu^V�f  Ä � u � l ] mBl ] g;� rVt h _ hkc ["� c3g \ cnm u _ rV\ �i["}f{3] g�m ��[ g { h {Vrn} h t hkm�e [�\"ts]z�i� d�g ]z{V]?\ m ]zw c3g r � ]?t hkc3g r m ]?w} e�mil ]�r g _ l"hkm ] _ m [ g ]Vu hkm � hk�­d tk] � ]?\ m r mBhsc \1uRrV\"w mil ] c3d ] g r mBhkc \�rVt d"g r _ mih _ ] � ¬�\§x c3g�m ["\�r m ]?t e u _ c3� �d"g�c3�­h �i]z�5x gicV� c [ m � h w"]�~®] �·j"� u§]�¢ m ] g \�rntst e u c3g�hsj3h \�r mih \ j x gicV� l"hkj3l ] g t|r e ] g � c x rV}"� mig r _ mBhkc \ c3g x gic3�cVmil ] g ]?\ mihkmBh ]?�¯r m&mBl ]D�ir � ]Dtsr e ] g&c x rV}"� mBg r _ mBhkc \1u cVg x g�c3� ��[ d"d�c �i]zw"t e ��] _ [ gihkm�e �¼\"]?[ mig rVt)r d�d t h _ r��mBhkc \"� �5c x m ]z\ _ rV\yts]?rVw mBc _ cV�­d"g�c3�Zh �i]z�Nx gicV� � hkmil"h \�~ rn»£] _ mih \ jFmil ] hs�Zd ts] � ]z\ m r mihsc \ c x r d r g�mih _ �["tsr g&� ] _ l rV\ h � ���&c3g x gicV� }£]zt c � ~ ��["}f{3] g9mBh \ j r � ] _ l rn\ h � � } eµm r �­d ] g�h \ j � hkmilªhkm �&["\"w"] g t ePh \ jw"] d ]z\"w"]?\ m _ c3�Zd�c \"]?\ m � ��� º \"] c x mBl ]Ãx®["\�w�r � ]?\ m rVt _ l rVtkts]?\ j ]?��rVw�w g ]z�i�i]zw l ] g ] h � mBc }�]yrV}"ts]mBc w"]z� hkj \1u hs�Zd tk] � ]?\ m u�rn\"w c3d ] g r m ]��i[ g { h {nrV}"tk]�� e � m ] � ��w"]z� d"hÂm ] mBl ] d"g ]z�i]?\ _ ] c x _ c3�Zd£c \�]?\ m �zu

Å �

Page 31: Practical Architectures for Survivable Systems and Networks (Phase

h \§x c3gi� r mBhkc \1u�rV\"w h \"w h { h w"[�rVtk� c x5["\ � \ c �&\ mig ["� m � c3g9mBl"h \"]?��� � rV���5]?tst�rV�¶�irV} cnm ]?[ g ��~ ] �·j"� u _ e �}�] g�m ] g�gic3g�h � � ¹ W3X3^ Ä|� u5rV\"w mBl ] g ]?} e mBc²d"g ]z{V]?\ m u½w�]zx®]?\�wbr j r h \"� m u c3g r m ts]?rV� m w�] m ] _ m r mim ] �Zd�m ]zw_ cV�­d"g�c3�Zh �i]z�Dx g�c3�/c [ m � h w"]Vu¾� hÂmBl"h \1u c3g }�]?t c � � � l"h � h � h \ ]?���i]?\ _ ] � l r m �N] � ]?rV\4} e �i[ g { h {f�rV} h t hÂm�e � h \ mBl ] _ c \ m ]�¢ mZc x j ]?\"] g rVt h�� ]?w w"] d ]?\�w"]?\ _ ] c \ d�cVm ]z\ mBh rntst e ["\ � \ c �&\�]?\ mBhÂmBh ]?� � ¡ c3g]�¢�r �Zd tk]Vu§r d r g9mBh _ ["t|r g t e w h _ ["t m _ l rVtstk]?\ j ] h � mBc ]z\"�i[ g ] mBl r m½mBl ]#] � }£]zw"w h \ j � c x�� c ["\"w _ g�ePd�mBc �j3g r d"l"h _ rVt j3c3gihÂmBl"� � _ rV\�\ cVm }�] _ cV�­d"g�c3�Zh �i]zwª}�] _ rn["�i] c x h \ l ] g ]?\ m �5]�r � \�]?�i��]?� h \ mil ]F["\"w�] g t e �h \ j _ c3�Zd [ m ] g � _ cV�­� [�\ h _ r mBhkc \ h \�x g rV� mig [ _ m [ g ]?�¶~®] �·j"� u l r g w§�½r g ]Vu �Zh _ gic _ c w"]Vu c3d ] g r mBh \ j � e � m ] � �zuw�r m rV}�rV��] � rV\"r j ] � ]?\ m u�rV\"wµ\"] m � c3g��Ph \ j'� � rV�&w h � _ [��i�i]zw h \ ¹ ^n�f� Äv�

o§[ g { h {nrV} h t hkm�e�h ��rV\ ��� ��� ��� ��d"g�c3d ] g�m�e�c x mil ] c {3] g rVtkt�� e � m ] � ��rV\"wª\�] m � c3gi� � � � l r m#h �?u hkm¯h �\ cVm w"]�±�\�rV}�ts]�rV\"wªrn\�rVt e � rV}"ts] h \ mil ]D� � rVtstKu"}£] _ rV[��i] hÂm¯h � mBl ] _ c \"�i]� P[�]?\ _ ] c x mil ] _ c3�Zd£c � hkmihsc \c x mBl ]��i["} m ]?\"w�]?wbx®["\ _ mBhkc \�rVt hkm�e �Ihkm�� [�� m }�] _ c \"� h w"] g ]zw h \ mBl ]µt|r gij ] � q�\ cVmil ] g � c3g w"�zu hkm�h �\ cVm r d"g�c3d ] g�m�ebmil r m _ rV\ }�] h w"]z\ mBh ±"]?w � hkmil rn\ e�c x mil ] _ c \"� mBhÂm ["]z\ m _ c3�­d�c \"]z\ m � � q�w"]?rVtst e uhkm � l"c ["tkw+}�]�w�] gih {nrV}"ts] h \ m ] g�� � c x d"gic3d ] g9mBh ]?� c x mil ] _ c \"� mBhkm ["]?\ m x®["\ _ mBhsc \�rVt hÂm�e c \ � l"h _ l+hkmw"] d ]z\"w"�?uPrV� w"]?� _ g�h }�]?w h \ mil ]��T�3 VXV� � c3g���c x�p c } h \"� c \�rV\"w���]z{ hÂmim ¹ Wf^3^ Ä�c \ mil ]&o�p&q'( h ] g r g _ l"h _ rVt¨�]z{V]?t c3d"� ]?\ m � ] mil"c w c t c3jne ~ (�¨ � � rV� d r g9m c x mil ] � o º o�]z» c3g9m�� � q�\ d"g r _ mih _ ]nu hkm � r e \ cVm }�]¯� cw"] gih {nrV}�ts]VuPrV� h \ mBl ] _ rV�i] c x _ c {V] g�m _ l rV\"\"]zts� mBl r m r gih �i] c \"t e }�] _ rV["��] c x �Zc w�["ts] _ cV�­d�c � hÂmBhkc \ �

o m ] d"l rn\ h ] ¡ c3gig ]?� m#h \ l ] g�h \ mBg�c w"[ _ mBhkc \ mBc�mil ]��T�V��� a½� �)o d"gic _ ]z]?w h \ j � ¹ �TX3� Ä u � rV\ _ e ��]z{3]��� c \ ¹ �¸ VW Ä u (�]?r mBl ] g ( h \ mBc \ ¹ �¸^3 Pu#�¸^V� Ä u��1r �'h \ mil"h \ c � rV\"w ��]?] ¹ W3�V� Ä u�rV\"w�¨ � ° � � g rn�BrVw ¹ W3X3� Äd"g�c { h w"]F� cV� ]�}�r _ �'j3gic ["\"w c \©] � ] g�j ]?\ m�d�gic3d ] g9mBh ]z� � �1r �Ph \ mBl"h \ c ��rn\"w²��]?]Fw"]�±�\"]�rV\©] � ] gij ]z\ md"g�c3d ] g�m�e rV� c \�] mBl r m�hkm � _ c \"� mihkm [�]?\ m _ cV�­d�c \"]z\ m ��w c \ cnm �Br mBh �9x e3� � g rn�BrVw©w g r��&� c \ � ]�rV��[ g ]��� ]?\ m�mil ] cVg�e rV\"w�w"] _ h � hsc \�rV\�rVt e � h � ¹ W3Xf  Ä)mic � l"c � mBl r m ��[ _ lªd"g�c3d ] g�mih ]z��r g ]D\ cVm _ c3�Zd�c � hÂmBhsc \�rVtrV\"wµrVtk� cFmil r m �i[ _ l�d"g�c3d ] g�mih ]z�&r g ]�\ cnm�� rV}�� c tk[ m ] � � w h »�] g ]?\ m � m r � ] l"c tkw"] g � � r e�l rT{V]�w h »£] g ]z\ mh w�]�rV�5rV} c [ m mBl ] � ]?rV\ h \ j¶c x mBl ] d"g�c3d ] g�m�eV� (�] g5mBl ]?� h ��� c3g�� rnts� cDd"g ]?�i]z\ m � mil ] � ] mil"c w c x � ["t mih �_ g�hkm ] gih rDw�] _ h � hkc \ � r �'h \ j ~ h \­r�� d ] _ h ± _ x g r � ]z� c3g���� rV�NrV\ r d�d"gic r _ l x c3g mBl ] � ]?rV�i[ g ] � ]?\ m ~ c \�r� c ["\"w mBl ] c3g ] mBh _ rVtR}�rn� h � ��c x1�i[ _ lyd"g�c3d ] g�mih ]?� � ( h \ mBc \ ¹ �¸^V� Ä�c }"�i] g {3]z� mBl r m ["\"w�]?� hkg rV}�ts]#] � ] gij ]z\ m}�] l r�{ hsc3gIh � c x m ]z\ mil ] g ]z�i["t m�c x h \ _ c3�Zd tk] m ]#� d ] _ h ± _ r mBhsc \1u�rV\"w _ rn\µ}�]�x c3gi� rVtkt e rV\�rVt e � ]?w �

# � ��� � � <"J %�<�STERQ"!b8�E�L H fH®>P= �¼ERQ ��>���)Q�H S !�$ J£ST>�RQ�H®S !

�<�J % ��<�H L <�� H LKH S !

� l ]¯\ cVmihsc \"� c x � ["t mBh ts]z{V]?t"��] _ [ gihÂm�e ¹ Wf^Pu'W3W�u'WV�§u§W3�Pu'W3� Ä u � ["t mBh tk]z{V]?t h \ m ] j3g�hkm�e ¹ �'^ Ä uPrV\"w � ["t mBh ts]z{V]?tr�{nr h tsrV} h t hkm�e ¹ ^V�f  Ä _ l r g r _ m ] gih�� ] l"h ] g r g _ l"h _ rVt � rV\"w"r mBc3g9e d�c t h _ h ]?�;x c3g _ c \�±�w�]?\ mBh rVt hÂm�e u h \ m ] j3gihÂm�e urV\"w r�{nr h tsrV} h t hkm�e u g ]?� d ] _ mih {3]zt eV� q�\ � � � � � � � � � � � � � � � � � ~ � �)o � u h \�x c3g�� r mihsc \ h ��\ cVm�d ] gi�Zhkm�m ]zwmBc ³ c � x gic3� c \"]�]?\ mihkm�eªmic rV\ cVmil ] g ]?\ mihkm�e«mil r m¶l rn�D}�]?]z\4rn�i� hkj \"]zw rÃt c �5] g ��] _ [ gihÂm�e ts]z{V]?t � q�\� � � � � � � � � � � � � � � � � � ~ � ��q � u \ c ]?\ mBhÂm�eªh � d ] gi�Zhkm�m ]zw mBc w"] d ]z\"w²[ d£c \²rV\²]?\ mBhÂm�e�mil r m�l rn��}£]z]?\rV��� hsj \"]?w�rÃt c �5] g�h \ m ] j3g�hkm�e ts]z{V]?t � q�\ � � � � � � � � � � � � ��� ��� � � ��� � � ~ � ��� � u1\ c ]?\ mBhÂm�eªh � d ] gi�Zhkmim ]?w micw"] d ]z\"w c \µrV\µ]?\ mihkm�e mil r m&l rV�&}�]?]z\«rV��� hkj \"]?w�r�t c �N] g r�{Vr h t|rn} h t hkm�e ts]�{3]zt ��#t mBl"c [ j3l�hkm�l rV��}�]?]z\ mil ]��i["} � ] _ m c x _ c \"� h w"] g rV}"ts] g ]?��]�r g _ l;h \��i] _ [ gihÂm�e�d�c t h _ h ]z��rn\"w � ] g \"]?t h�� ]?w

� e � m ] � r g _ l"hÂm ] _ m [ g ]?�zu�rV\"w l"hkj3l t e mic [ m ]?w�} e+mBl ]²¨�] d r g9mB� ]?\ myc x�¨�]zx®]z\"�i] ~®�i]z] aNl r d�m ] g � � u� ["t mBh ts]z{V]?t��i] _ [ g�hkm�e�l rV� g ] � r h \"]?wµ{3] g9e w h� _ ["t m�mic r _ l"h ]z{3] h \ g ]�rVt h � mBh _ � e � m ] � �¶rV\�wª\"] m � c3g�� � �� l"h � h �Iw"["] mic�� rV\ e x r _ mic3g �zu h \ _ ts["w h \ jFh \�rVw"]� '[�r _ h ]?� h \ mil ]¶¨ c ¨ _ g�hkm ] gih r�u"rn\Ã["\f� h tst h \ j \"]?��� c x_ cV�­� ] g _ h rnt)� e � m ] � d"g�c { h w"] g � mBc w"]�{3]zt c3d � e � m ] � �zu�rV\"w²rV\©["\f� h tst h \ j \"]z�i� c x \ c \§��¨ c ¨ � e � m ] �r _ P[ hsg ] g � mBc _ c \"� h w"] g ��[ _ l � e � m ] � � � � g _ l"hÂm ] _ m [ g rVt�rVt m ] g \�r mih {3]z�¯r g ] _ c \"� h w"] g ]?w h \ aNl r d§m ] g   �� UF<9� >1�Q35' �! !+ �*�G��-���)�=��/L�V�?)�,�Y��)*�*+B�Q&" !+ ���?,2?�!&�,a/:35-�+B/?=��*�1��-@#

Å#`

Page 32: Practical Architectures for Survivable Systems and Networks (Phase

o migih _ m�� [�t mBh ts]�{3]?t h \ m ] j3g�hkm�e�h � mil"c [ j3lfm�mic }£]�r�� � �Nr g w mBc ]z\�x c3g _ ] h \ d"g r _ mih _ rVt � e � m ] � �zu�}£]��_ rn["�i] l"hsj3l � h \ m ] j3g�hkm�e ["�i] g �½rn\"w d"g�c _ ]?���i]?� c x m ]z\­w"] d ]z\"w c \­]?w hÂmBc3g �?u _ cV�­d"h ts] g �?uft h } g r g�e;gic [ mBh \�]?�?uw"]�{ h _ ]­w gih {3] g �?u�rn\"w � c�c \1u mil r m r g ] m�ePd"h _ rVtst e \ cVm \"] _ ]?���Br g�h t e²mig ["� m � c3g9mBlfe rV\"w mil ] g ]zx c3g ] r g ]gih � �fe�mBc w�] d ]?\"wÃ[ d�c \ � ( c �N]�{3] g u mBl r mNh � d"g ] _ h �i]zt e�mBl ]�x®["\"w"r � ]z\ m rVt h \ m ] j3gihÂm�e�d"gic }"ts] � h \ �Zc � m� e � m ] � r g _ l"hkm ] _ m [ g ]?� � � l ] hs�Zd t h _ hÂm �5]?} c x mBg [�� m � l"c [�tswÃx c3g _ ] mBl"c ��]�[ mBh t hkm�e x®["\ _ mBhkc \"� mBc }�]�r mts]?rV� m rn� mBg [�� m � c3g�mil'e � hÂmBl�g ]z� d ] _ m5micDh \ m ] jVgihkm�e u3}�] _ rn["�i] mBl ] e�� ["� m rVtst§}£] _ c \"� h w"] g ]?w�� hkmil"h \ mBl ]d ] gihk� ] m ] g¯c x mBg ["� m � c3g9mBl"h \"]?��� � � l ]�\ cVmBhkc \ c x j ]z\"] g rVt h�� ]?wµw"] d ]z\"w"]?\ _ ] h � c \"]D�Nr eµc x¾� c3gi�'h \ j� hkmil"h \ mil r m _ c \"� mig r h \ m � hkmBl�c [ m ] hkmBl ] g �Br _ gih ± _ h \ j�mBl ] d�c �N] g&c x mil ]�}�rV� h _�_ c \ _ ] d�m � c3gIc x h \ migic �w"[ _ h \ j \"]�� {P["ts\�] g rn} h t hkmBh ]?� mBl r m&g ]?��["t m x gicV� h \§x c3gi� rVt�w"]z{ h r mBhsc \"�½x gic3� � mBg�h _ m&h \ m ] gid"g ] m r mBhsc \"� �

# � ��� � � �)L S¸HKL®>���>§L ���)Q"��H��"<�� H LKH S !q�\ mil"h � g ] d£c3g9m u¾�5] _ c \"� h w"] g�mBl ] _ c \ _ ] d�m [�rntN["��] c x mil"h � �'h \"w c x � rn\"w�r mic3g�e }�rn� h �Dx c3g �i[ g { h {f�rV} h t hÂm�e3� o mBgih _ m t e � d ]�r �'h \ j u mBl�h �N� c ["tkwµtk]�rVw mic r�t|r m�mBh _ ]��¼}�rV�i]zw � rn\"w�r mic3g�e­d£c t h _ e x c3g½� ["t mBh ts]z{V]?t�i[ g { h {nrV} h t hÂm�e�mBl r m w hsg ] _ m t eDhs�Zhkm r m ]z� mil ] � �)o£u � ��q ufrV\"w � ��� d�c t h _ h ]?� � ¡ c3g � hs�Zd t h _ hÂm�e u¸�N] g ]zx®] gmBc&mBl�h � d£c t h _ e rV�)� hk�­d t e � � � � � � � � � � � � � � � � � � � ��� � � ~ � � � ��� q�\;rV\ c {3] g � hs�Zd t h ±�]?w¶x c3gi� ["t|r mihsc \ c x mBl ]� ["t mBh ts]z{V]?t"��[ g { h {Vrn} h t hkm�e�d£c t h _ e uf\ c � e � m ] �*c3g \"] m � c3g�� ]?\ mBhÂm�e�h ��rVtkt c �N]zw mBc w"] d ]?\"w c \­rV\­]z\ mBhkm�emBl r mIl rV�N}£]z]?\µrV�i� hsj \�]?wyr;t c �5] g �i[ g { h {nrV} h t hkm�e tk]z{3]zt ~ [�\"ts]z�i�IrV\Ã]�¢ d t h _ hkmNj ]?\�] g rnt h�� ]?w§�¼w"] d ]?\�w"]?\ _ ]� ] _ l rV\ h � �/h ��]z� m rV}"t h � l ]zw mil r m�d ] gi�Zhkm � mBl ]­["��] c x � ] _ l rV\ h � � � c x½t c �N] gDmig ["� m � cVg�mBl�h \"]z�i�?u rn�h tkts["� mBg r m ]zw h \©o§] _ mBhkc \ � � ^ � � ��� � l ]z�i] _ c \ _ ] d�m ��r g ] _ c \"� h w"] g ]?w h \ mil"h � g ] d�c3g9m#mBc­h \ _ ts["w�] j ]z\"] g �rVt h�� ]zwÃw"] d ]?\�w"]?\ _ ] �¡ c3g w"]?� _ gihkd�mBh {3] d [ gid�c �i]z�?u��5] hk�­d t h _ hkm t e rn�i�i[ � ] mBl ] d�c ��� h } h t hÂm�e�c x _ c3�Zd r g�mi� ]z\ m � h \�]?r _ lÃc x

mBl ]?�i] d�c t h _ h ]?��~ � �)o£u � ��q u � ����u�rV\"w � � � � u�rVt mil"c [ jVl �N]�w"]z� _ g�h }�] mBl ] d�c t h _ h ]?� h \ m ] gi� � c xts]�{3]zts�­~®� hÂmBl"c [ m _ r m ] j3cVgih ]z� ����´ ] _ rV["�i] c x mBl ] _ c3�­d r g�mi� ]z\ m �Z~®x r �Zh t h r gImic r _ h rV\"rVw c � c x � �)orV\"w � ��q � u mil ] c3g w"] g�h \ j�c \ mBl ]�ts]z{V]?tk�FrV\"w _ c3�Zd r g�mi� ]z\ m � j ]?\"] g r m ]?��r � r mBl ] � r mBh _ rVt�tsr mimih _ ]h \ ]?r _ l�h \"� m rV\ _ ] � � l ["�?u�� l ]?\��N] g ]zx®] g mBc � rV\"w�r mic3g�e�d�c t h _ h ]z� h \ mBl"h � _ c \ m ]�¢ m u¯�N] hk�­d t et|r mimBh _ ]���}�rV��]?w d�c t h _ h ]z� g r mBl ] gImBl rV\ � ["� m _ c3�Zd ts] m ]zt e cVg w"] g ]?wµts]�{3]zts��~®� hÂmBl"c [ m _ c3�Zd r g9mB� ]?\ m � ���q�\ mBl ]�rn}"�i]z\ _ ] c x j ]?\"] g rVt h�� ]?w©w"] d ]z\"w"]?\ _ ]Vu � migih _ m � � � c3g w�] gih \ j � c ["tsw �Zc � m t hs� ]?t e ��[�»�] g

mBl ]��ir � ] �Ph \"w c x d"gic }�ts] � � mBl r m r gih �i] h \ mil ] d"g r _ mih _ rnt�["�i] c x�� migih _ m � ��q � \"r � ]zt e u mBl ]g ]?rVt h�� r mihsc \ mil r m ]?\ cVgi�Zc ["� d£c3g9mBhkc \"� c x�rV\ eZj3h {3]?\­w h � mBg�h }"[ m ]?wZ� e � m ] � � ["� m }�] c x l"hsjVl�h \ m ] j3g�hkm�erV\"w l�hsj3l ��[ g { h {Vrn} h t hkm�e3� � l ]©\ cVmihsc \ c x j ]?\�] g rnt h�� ]?w w"] d ]z\"w"]z\ _ ] mBl ] g ]�x c3g ]ªrVtst c �&� mBl ]«� mBg�h _ md r g9mBh rVt c3g w"] g�h \ jImic }�] g ]zt|r�¢§]?wDt c _ rntst e � l ]z\"]z{V] g hkm�h � d�c ��� h }�ts] mic r _ l�h ]z{V] j3g ]?r m ] g�mig ["� m � cVg�mBl�h \"]z�i�c [ m�c x�tk]?��� mig ["� m � c3g9mBlfe _ c3�Zd£c \"]?\ m �zu�rn� h tkts["� mBg r m ]zw h \ªoP] _ mihsc \ � � ^ � ��� � hkmBl�c [ m�g ]?tsr�¢ h \ jZhkm¯h \mBl ]Dtsr gij ] �

¡ c3g g ]?rVw"] g �N� l"c � l ["w"w"] g r mNmil ] _ c3�Zd ts]�¢ hÂmBh ]?��rV\"w h \ _ c \f{3]?\ h ]?\ _ ]?� h \ mBgic w"[ _ ]?w } eZ� ["t mBh ts]z{V]?td�c t h _ h ]z�?u��5] l rV� m ]?\ mBc rVw"w mBl r m�mBl ] � � � d"gicVd ] g�m�e¶h � _ c \"� h w"] g ]?w c \"t e rV�)r&� mig [ _ m [ g rVt c3gij rV\ h��zh \ j_ c \ _ ] d�m#g r mBl ] g&mBl rV\�rV��rV\µ]�¢ d t h _ hÂm&j3c rVt c x¾w"]?� hsj \�rV\"w hs�Zd tk] � ]?\ m r mihsc \ � ¡ [ g�mBl ] gi�Zc3g ]Vu�]z{V]?\ h x� � � �N] g ] h \ m ] gid"g ] m ]zw;��] gihkc ["��t e u mBl ] g ] h ��rntk�Nr e � r¯t hs� ]?t hkl"cPc w mil r m�mBl ]5tk]z{3]zts�)rV\"w _ cV�­d r g�mB� ]?\ m ��Zhsj3lfm }�]¶�i] m [ dµh \y�i[ _ l r��½r eÃmBl r mImBl ] g ]¶� c ["tswµ}£]DrFx®["\"w"r � ]z\ m rVt _ c \�³ h _ m r �Zc \ jFmBl ] � � o�u� ��q u � ���;u¯rV\�w � � � _ c \"� mig r h \ m � mBl r m � c ["tkw d"g ]z{V]?\ m ]�¢ d ] _ m ]zw g ]z�i["t m �yx gic3� l r d"d ]?\ h \ j"�aNc \"��]� '["]z\ m t e u � � � h � h \ migic w"[ _ ]?w c \"t e�mic ]?\ _ c [ g r j ] mBl ] h \ m [ hÂmBh {3]&w"]?� hsj \ c x�� e � m ] � � h \Z� l�h _ l�5];r�{ cVh wy["\"\"] _ ]z�i�Br g�e w"] d ]?\�w"]?\ _ ] c \ _ cV�­d�c \"]z\ m � mBl r m r g ] h \ l ] g ]z\ m t e ts]?���&�i[ g { h {nrV}"ts]Z~ h \ mBl ]�i]z\"�i] c x j ]?\�] g rnt h�� ]?wyw"] d ]z\"w"]?\ _ ] ���� l"h � h \ hÂmBh rnt5w h � _ ["�i� hsc \ g ] d"g ]z�i]z\ m � rª± g � m r d"d"g�c ¢ hk� r mBhsc \ mBc � l r mZh ��r _ m [�rVtst e \�]?]?w�]?w � q�\

Å �

Page 33: Practical Architectures for Survivable Systems and Networks (Phase

aNl r d§m ] g  Pu��N]�rnw"w g ]z�i� mBl ] d£c ��� h }"ts] _ c \�³ h _ m �¶r �Zc \ j�mil ]��i["} g ]� '[ hkg ] � ]z\ m � c x��i[ g { h {nrV} h t hkm�eµh \mBl ] _ c \ m ]�¢ m�c x j ]?\�] g rnt h�� ]?wyw"] d ]z\"w"]?\ _ ] �

(*)�� � �5( �����N( 9���$�9�9�� % � ,�- .0�5,����N( �����N( �"9$���9�� %

� c�h tkts["� mBg r m ] mBl ] hs�Zd£cVg�m rn\ _ ] c xRw"] d ]z\"w"]z\ _ ] c \ d"gic3d ] g9mBh ]?� c x�["\"w"] g t e§h \ j rn}"� mig r _ mBhsc \"�?u _ c \"� h w"] gmBl ]�\"] _ ]?�i� hkm�e²c x�w"] d ]z\"w h \ jÃc \�r t h x®]�� _ gihÂmBh _ rVt�� e � m ] � x cVg#mBl ] d�gicVm ] _ mihsc \ c x l [ � rV\²�Br�x®] m�e3��� q�\�i[ _ l rI� e � m ] � uV�irnx®] m�e [�t mBhk� r m ]?t e %)>'O�>PJ %)= �)O�E�J mBl ] _ c \�±�w�]?\ mBh rVt hÂm�e u h \ m ] j3gihÂm�e u¸rV\�w;r�{nr h tsrV} h t hkm�ec x5} cnmBl©mBl ]�� e � m ] � rn\"w hkm ��w"r m r � q m¶� r e rVtk� c w"] d ]z\"w c \ h \�x c3gi� r mihsc \��i[ g { h {nrV} h t hkm�eV� q m¶� r ex®[ g9mBl ] g %�>PO�>PJ'% ��O�E�J _ c3�­d�c \"]z\ m rV\"w�� e � m ] � g ]?t h rV} h t hÂm�e u�rV\"w c \ g ]?rVtÂ� mBhs� ] d ] g x cVgi� rV\ _ ] � q mrVtk� c ["��[�rVtst e %�>'O�>§J'%)= ��O�E�J mBl ] _ c3gig ] _ m \"]?��� c x � [ _ lDc x mBl ] r d"d t h _ r mihsc \ _ c w"] � q�\ mil ] �i]z\"�i] mBl r m]�r _ l t|r e ] gNh \�r l"h ] g r g _ l"h _ rVt�� e � m ] � w"]z� hsj \ %)>'O�>PJ'% = ��O�E�J mBl ] d"g�c3d ] g�mih ]?� c x mil ]#t c �5] g t|r e ] g �zumBl ]y�Nr e h \ � l"h _ l�mBg ["� m ]?w _ c3�Zd [ mih \ j }�rn�i]?�­r g ]µtsr e ] g ]?w�}£] _ c3� ]?� hs�Zd�c3g�m rV\ m x c3g w"]�{3]?t c3d"h \ jw"] d ]z\"w�rV}"t e �irnx®]�� e � m ] � � � d r g9mBh _ ["tsr g t e©h \ mBl"c ��] _ rV�i]z� h \ � l�h _ l mBl ] j ]z\"] g rVt h�� ]?w %)>'O�>PJ'% =E�J g ]?tsr mBhkc \ _ rn\«}�]D[��i]?w �­cVg ]Dr d"d"g�c3d"g�h r m ]?t e�h \"� m ]?rVw c x %�>PO�>PJ'% = �)O�E�J mBc r _?_ c3�Z�­c w�r m ]¶rV\hs�Zd tk] � ]?\ m r mihsc \­}�rV��]?w c \µtk]?��� mig ["� m � cVg�mBlfe _ cV�­d�c \"]z\ m � �� l ]©�ir � ]©w�] d ]?\"w"]z\ _ ] � hÂm [�r mihsc \ h � mBg ["] c x��i] _ [ g ]�� e � m ] � �zu h \ � l"h _ l ]�r _ l t|r e ] gÃh \ mBl ]

rV}"� mBg r _ mihsc \ l"h ] g r g _ lfe ~®] �·j"� u _ c \"� h � mih \ j©c x#r � ] g \"]?tKuNr mig ["� m ]?w _ cV�­d [ mBh \ j }�rV��] x c3gFd"g�hs�ZhkmBh {3]�i] _ [ g�hkm�e u5w�r m rV}�rn�i]?�zuNr d"d t h _ r mihsc \ � c x m �Nr g ]Vu½rn\"w ["�i] g � c x m �Nr g ] �F� ["� m ]z\�x c3g _ ]Ã� cV� ]Ã��] m�c x��i]��_ [ gihkm�e4d"gicVd ] g�mBh ]?� � � l ] d"g�c3d ] g�mih ]z� � r e w h »£] g x g�c3� t|r e ] gFmBc t|r e ] g u�rV\�w {nr g�hsc [�� mBg ["� m � c3g�milfe� ] _ l rV\ h � � � � r e ]�¢ h � m r m ]?r _ l tsr e ] g u }"[ m�mil ] d"gic3d ] g9mBh ]?�Dr m r d r g�mih _ [�t|r g tsr e ] g r g ]Zw�] gih {nrV}"ts]x gicV� t c �5] g ��t|r e ] g&d"gicVd ] g�mBh ]?� �q�\ mBl ]y��] _ [ gihkm�e _ c \ m ]�¢ m u � rV\ e \ cVmihsc \�� c x _ c3�Zd"gic3�Zh ��] ]�¢ h � m�� ¡ c3g ]�¢"r �­d tk]Vu _ cV�­d"g�c3�Zh �i]

�Zhsj3lfm ]?\ m r h t�r _z_ ]?��� h \ j �i[ d"d£c �i]?w�t eµg ]z� mBg�h _ m ]?w«w�r m r§u h \"�i] g�mih \ j ["\f{nrVt h w�r m ]zw _ c w�] h \ mic r mBg ["� m ]?w]?\f{ hsg�c \ � ]?\ m u§rVt m ] g�h \ j ]�¢ h � mih \ j ["�i] g w�r m r c3g c3d ] g r mih \ j ��� e � m ] � d r g r � ] m ] g �?u _ rV["� h \ j rDw�]?\ h rVt c x�i] g { h _ ]Vu�±"\"w h \ j rV\Ã]?� _ r d ]#x g�c3� r l"hsj3l t e�g ]z� migih _ m ]zw � ]z\P[ h \ m ] g x r _ ]nu c3g5h \"� m rVtkt h \ j¶c3g½�Zc w h x ePh \ jr g ["tk] h \µr g ["tk]��¼}�rV�i] mil r m&g ]z�i["t m � h \y��["}f{3] g � hkc \ c x¾rV\µ]�¢ d ] g�m � e � m ] ���� l ] g ] h �&rV\ hs�Zd£cVg�m rn\ m w h � mBh \ _ mihsc \y}�] m �5]?]?\ l r�{ h \ j�mBc w"] d ]z\"w c \µt c �5] g ��t|r e ] g x®["\ _ mBhsc \�rVt hÂm�e

~®� l ] mBl ] g hÂm h � mBg ["� m � c3g9mBlfeFc3g \ cVm � rV\"w l r�{ h \ j � c3� ] � ]?rV\ h \ j x®["tPrV���i[ g rV\ _ ] mil r m mBl ]5t c �N] g �¼t|r e ] gx®["\ _ mBhkc \�rVt hkm�eµh ��r _ m ["rVtst e \ c \ _ cV�­d"g�c3�Zh � h }"ts]¶["\�w"] g r�� h w�] g rV\ j ] c x5r _ m [�rVt mBl"g ]�r m � �F�¯c \ _ c3� �d"g�c3�­h � h } h t hkm�e�h � d r g�mih _ [�t|r g t eZhs�Zd£cVg�m rn\ m � hkmBlyg ]?� d ] _ m�mic �i] _ [ gihÂm�e uR�Br�x®] m�e uRrn\"w g ]?t h rV} h t hÂm�e3�� cnm ]?\ mih rVtkt e u"r­�i[ d"d£c �i]?w�t e � c [�\"wª� e � m ] � _ c ["tsw�}£] g ]z\"w"] g ]?w«["\"� c ["\"w h \ªrV\ eyc x mBl"g ]?];}"rV� h _

�Nr e �z�� ��E��4O)Q¸E �4HK=?> �vQ�E�� E���S¸=�H�%)> ~ h \ m [ hÂmBh {V]?t e u rn} c {3] c3g tsr m ] g rVtkt e

x g�c3� ]?tk�i]z� l ] g ]yr m;mBl ]�ir � ]¶rV}"� mig r _ mBhkc \yt|r e ] g �

� ��E��4O)Q¸E �4HK=?> �¼Q¸E�� C­H®S¸:)H J ~ h \ m [ hÂmBh {V]?t e u h \"� h w"]¶r _ c3�Zd�c \"]?\ m¯c3g tsr e ] gB�

� ��E��4O)Q¸E �4HK=?> �¼Q¸E�� ��>PL EPC ~ h \ m [ hÂmBh {V]?t e u�[�\"w"] g \"]�r mBlR�� r _ l�c x mBl ]z�i]&� hÂm [�r mihsc \�� _ c ["tsw�}�] _ rV["��]?w h \ m ]z\ mBhsc \�rVtst e u�}"[ m _ c ["tswZrVtk� c�l r d"d ]z\Zr _?_ h w"]z\ m rVtst e3�

~ ¡ c3g w"]?� _ g�hsd�mih {3]N� hs�Zd t h _ hÂm�e u�r � � ��� � r e }£]Ir d ] g � c \1u'r d"g�c _ ]?�i�zu'rV\�r j ]?\ m u'r#��["}"� e � m ] � uPrV\ cnmBl ] g� e � m ] � u c3g rV\ eÃcVmil ] g _ c3�­d [ m ] g � g ]?tsr m ]zwµ]z\ mBhkm�eV�À�

�0_!�?+B&!&*��%��*+B,/@+B&!35>:35�?�*��>G6�)�,-�� � � ��� #

Å �

Page 34: Practical Architectures for Survivable Systems and Networks (Phase

� aNcV�­d"g�c3�Zh �i]�x g�c3� c [ m � h w"] m�ePd"h _ rVtst e²c3gihkj3h \"r m ]z�¶x g�c3� rV\ r _?_ ]z�i� d�c3h \ mDmBl r mFh �D\ c3�Zh \"rVtst e]�¢ m ] g \�rVt mic�mil ] _ c3�Zd�c \"]?\ m }�] h \ j _ c3�Zd"gic3�Zh ��]?w �

q�\ _ rV�i]z� c x d [ gid�c �i]�x®["t _ c3�Zd"g�c3�­h �i]�x gicV� c [ m � h w"]nu mBl ] d ] gid ] mBg r mBhkc \ h � m�ePd"h _ rVtst e mBl r mc x r _ c3�Zd tk] m ]zt e ["\ d�gih { h ts] j ]?wÃ["��] gIc3g r d r g�mBh rVtst e�d"gih { h ts] j ]?w�["�i] g � l"c�j r h \��Ir _?_ ]?��� micd ] gid ] mig r m ]Ãr«x®[ g9mBl ] g _ c3�Zd"g�c3�­h �i] � q�\ j ]z\"] g rVtvu�rn[ mBl"cVgih�� r mBhkc \ � r e }£] [�\"\"] _ ]?���Br g9e ud�c �i� h }"t e }�] _ rn["�i] c x#rV\ ]�¢ d t c3hkm rV}"ts]Z³Rr�� h \ mBl ]y� m rV\"w�r g w h \ m ] g x r _ ] �½h \ � c3� ] _ rn�i]?�zurV[ mil"c3g�h�� r mBhsc \ � r e }�]¶} e§d rV�i��]?w �

q�\ _ rV��]?� c x½r _?_ h w"]?\ m rVt _ c3�Zd"g�c3�­h �i]Fx g�c3� c [ m � h w"]Vu mil ] _ c3�Zd"gicV�­h �i] � r e©g ]z�i["t m x gic3�rV\ h \�rnw�{3] g�m ]z\ m#d"g�c3j3g r � ] g�gic3gIh \«r l"hkj3l ] g tsr e ] gImil r m � c3� ] l�c � rn»£] _ m �#r�t c �5] g t|r e ] g uc3gIh \�rn\ cVmBl ] g&�­c w"["tk]�r mImil ]¶�Br � ]¶t|r e ] g x c3g � l"h _ lµmBl ] g ] h � h \�rVw"]� '[�r m ] h � c tsr mBhkc \ �

� aNcV�­d"g�c3�Zh �i] x gicV� � hÂmBl"h \ m�ePd"h _ rVtst e�cVgihsjVh \�r m ]?� h \"� h w"]Nr d r g�mih _ ["t|r g _ cV�­d�c \"]z\ m¾mBl r m h � _ c3� �d�gic3�Zh ��]?w1u§]�¢ h � mBh \ j r m r j3h {3]z\�tsr e ] gIc x rV}"� mBg r _ mBhkc \ �

q�\ _ rn�i]?� c x d [ gid�c ��]zx®["t _ c3�Zd"gic3�Zh ��]¯x g�c3� � hkmil"h \1u mBl ] d ] gid ] mig r mihsc \ h � d ] g x c3gi� ]?w } e r["��] g c3g d"g�c3j3g r ��mil r m�l rV��� c3� ] l�c � j r h \"]?w�r _?_ ]z�i��~®� hÂmBl�c3g � hÂmBl"c [ m rV[ mil"c3g�h�� r mBhsc \ ��micmBl ] h \ m ] g \�rVts� c x�r _ c3�Zd£c \"]?\ m uR��[ _ l rV� d"g�h { h tk] j ]zw � r h \ m ]?\�rn\ _ ]Dr _z_ ]?��� mic r�w�r m rV}�rV��]� rV\�r j ] � ]z\ m � e � m ] � u�\"] m � c3g�� _ c \ migic tkts] g u cVg rV[ mic3� r mBh _ m ]ztsts] gN� r _ l"h \"] � � l ] _ c3�Zd£c �\"]z\ m _ c ["tkw }�] _ c3�Zd"g�c3�­h �i]zw4} e rn\ rV[ mil"c3gih�� ]zw ["�i] g � l"cªh � �Zh �i[�� h \ j«d"g�h { h tk] j ]z�?u cVg} e r d ]?\"] mBg r mBc3g �Rc \ _ ]�r d ] g�d ] mBg r mBc3g&l rn� j r h \"]zw«r _z_ ]z�i� micZmil ] _ c3�Zd£c \"]?\ m�h \ m ] g \�rVtk�?u�i[ _ l r«w h � mih \ _ mBhkc \ � r e }�]yr _ rnw"] �Zh _ u }£] _ rV[��i] mBl ] d ]z\"] mig r mic3gFh ��\ c � �Zc3g ] c3g tk]?���h \�w h � mBh \ j [ h � l rV}"tk]#x gicV� rV\ h \"� h w"] g?� � l ["�?u _ c3�Zd"g�c3�­h �i]#x g�c3� � hÂmBl"h \ � r e x c tkt c ��x gic3�r _ c3�Zd"g�c3�­h �i]�x g�c3� c [ m � h w"] mBl r m ]?\�rV}�ts]?�¯r��i[�}"�i]� P[�]?\ m�d ]?\"] mBg r mBhsc \ �

q�\ _ rn�i]?� c x)r _?_ h w"]z\ m rVt _ c3�Zd"g�c3�­h �i]&x gic3� � hÂmBl"h \1u mBl ] _ c3�Zd"gic3�Zh ��] _ c ["tkw h \f{ c tk{V]#³Rr��&�c3gI� rVtkx®[�\ _ mihsc \"�½rV�i� c _ h r m ]?wy� hkmBlÃmil ] d r g�mih _ ["t|r g � e � m ] � _ cV�­d�c \"]z\ m?�

� aNcV�­d"g�c3�Zh �i]�x g�c3� }£]zt c � h � h \ hÂmBh r m ]zw4r m r«t c �5] g t|r e ] g;c xIrV}"� mig r _ mBhkc \ mBl rV\ mBl ]�t|r e ] g r m� l�h _ l�mil ] _ c3�Zd"gicV�­h �i] c x�r j3h {V]?\ _ c3�Zd£c \"]?\ m c _z_ [ g � ��aNcV�­d"g�c3�Zh �i]�x g�c3� }£]zt c � � r e¶g ]z�i["t mx g�c3� � rVt h _ hkc ["�¶r _ mBhsc \ c3g r _z_ h w�]?\ m rVt�x r h ts[ g ] c x&rV\ ["\"w"] g t ePh \ j�� ] _ l rV\ h � � c \ � l"h _ l4mBl ]d r g�mih _ [�t|r g _ c3�Zd£c \"]?\ m w"] d ]z\"w"� � q m�m�ePd"h _ rVtkt e rn»£] _ m � mBl ] d r g�mih _ [�t|r g _ c3�Zd£c \"]?\ m } e rVt m ] g�h \ jmil ]²� m r m ] c x�t c �5] g �¼t|r e ] g x®["\ _ mihsc \"rVt hÂm�e u c3gÃh \�� cV� ] _ rn�i]?� � ] g ]zt e } e�j r h \ h \ j r _z_ ]?��� mich \�x c3g�� r mihsc \ h \�r¶t c �5] g �¼t|r e ] g rV}"� mBg r _ mBhkc \ZrV\"w�["� h \ j�mBl r m�h \�x c3g�� r mBhsc \ h \�� c3� ]¯[�\"]�¢ d ] _ m ]?w�Nr e3� � l"h � h � gic [ j3l t e ]� '[ h {Vrnts]?\ m&h \ � ]�rn\ h \ jFmic � � � � ��� � � � � �

q�\ _ rV��]?� c x d [ gid�c �i]�x®["t _ c3�Zd"gicV�­h �i]#x g�c3� }�]?t c �¶u mil ] d ] gid ] mBg r mBhkc \ h � d ] g x c3gi� ]?wy} e r["��] g � l"cµl rV�¶� c3� ] l�c � j r h \"]?w²r _z_ ]z�i��~®� hkmil²c3g � hkmil"c [ m rV[ mBl"c3g�h�� r mBhkc \ �&mic t|r e ] g � c xrV}"� mBg r _ mihsc \²["\"w�] g t ePh \ j r d r g�mih _ ["t|r g _ c3�Zd£c \"]?\ m¶mBl r m¶h �¶}£] h \ j _ c3�­d�gic3�Zh ��]?w1u�� l�h _ l_ rn\ mBl ]?\�}�]&["\"w"] gi�Zh \"]zw­� hÂmBl"c [ m r mim r _ �'h \ j¶mBl ] _ cV�­d�c \"]z\ m�hÂm �i]ztkx �¾� ¢�r �Zd tk]?� h \ _ ts["w"]~9� ��c } m r h \ h \ j½mBl ]�[�\"]?\ _ g�ePd�m ]?w;x c3g�� c x�rV\¶]?\ _ g�ePd�m ]?w � ]?���Br j ]�} e�g ]�rVw h \ j r m ] �­d�c3g r g�e±�tk] h \;� mic3g r j ]Vu"~v^ � ±�\"w h \ j rV\ c _?_ [ gig ]?\ _ ] c xRr d r g�mih _ ["t|r g � c3g w h \;r g ]z� migih _ m ]zwFw�r m rV}�rV��]mBc � l"h _ l r _?_ ]?�i� h �¶\ cVm�d ] gi�Zhkm�m ]?w�} e � _ rn\"\ h \ j�mBl ]�w h � �©c \�� l"h _ l4mil r m w�r m rV}�rV��] h �� mic3g ]zw1u§rV\"w�~KW � ]zw hkmih \ j�mil ] g r�� m ]�¢ m�c x�rV\�]z\ '["]?["]zw � r h t � ]z�i�Br j ]¯rnx m ] g�hÂm�h � g ]?tk]�rV��]?w} e r­["��] g }"[ m }£]�x c3g ] hkm¯h ��r _ m [�rVtkt e �i]?\ m#c [ m } eymil ] � r h ts] gz� � l ["�zu _ c3�­d�gic3�Zh ��]�x gic3�}�]?t c � � r e x c tst c ��x g�c3� r _ c3�Zd"gic3�Zh ��]½x gic3� c [ m � h w"] c3g _ c3�Zd"g�c3�­h �i]Ix gicV� � hkmil"h \ mBl r m]?\"rV}"ts]z�¯r���["}"��]� '["]?\ m�d ]?\�] mBg r mBhkc \ mBc�mBl ]Dt c �N] g ��tsr e ] g&� ] _ l rn\ h � � � �

Å �

Page 35: Practical Architectures for Survivable Systems and Networks (Phase

a rV��]?� c x¶r _?_ h w"]z\ m rVt _ cV�­d"g�c3�Zh �i] x g�c3� }�]?t c � c x m ]z\ h \'{ c tk{V] mil ] g ]?��["t m � c x�³Rr��&� cVg� rVtkx®["\ _ mBhkc \"�Zr m t c �N] g tsr e ] g � c x¶rn}"� mig r _ mBhsc \ mBl r m�h \+� cV� ]µ�½r e rVt m ] gZc3g­cnmBl ] g � h ��]rn»£] _ m�mil ]�]�¢ d ] _ m ]zw }£] l r�{ hsc3gDc x mil ] d r g�mih _ [�t|r g _ c3�­d�c \"]z\ m�� ¡ c3g ]�¢�r �Zd ts]nu _ c \"� h w"] gr g r mBl ] g w g r � r mih _ ] g�gic3g¶mBl r m;c _?_ [ gig ]?w h \ mil ]�]?r g t e �T�3�VXV� h \ mil ] � q � aNc3�­d r mBh }"ts]� hs� ]��o l r g�h \ j o e � m ] � ~ a � o"o ��� � l ]Z]?\ mBhkg ]�["\"]z\ _ g9ePd�m ]zw4±�ts] c xN["��] gDd rV����� c3g w"�¶�NrV�d"g�h \ m ]zw c [ m rV� mBl ] � ]z�i�Br j ] c x mBl ]�w�r e x c3g ]�r _ l \"]���["�i] g t c3j3h \ � � l"h � g ]?�i[�t m ]zw­x g�c3� r� l�c3g�m � hsjVl'm ]?w�\�r �Zh \ j _ c \f{3]?\ mihsc \ h \ mBl ] _ c \ m ]�¢ m ]zw hkmic3g }�] h \ j ["��]?w«r m&mBl ]¶�Br � ] mBhk� ]} e�m � c w h »£] g ]?\ m�cVd ] g r mic3g � h \©r�� l r g ]?w©� e � m ] � w hsg ] _ mic3g�e ¹ ^3�VX Äv� � � cÃm ] �­d�c3g r g�e ±�tk]\�r � ]?���5] g ] mBl ]µ�Br � ]yx c3g ]�r _ l+h \f{ c _ r mihsc \ c x mBl ]µ]?w hÂmBc3g u½rV\�w mBl ] m ] �Zd£c3g r g�e ±�ts]z�}�] _ r � ] h \ m ] g _ l rV\ j ]?w }�] m �5]?]z\ m � c w h »£] g ]?\ m [��i] g � h \ mBl ] �ir � ]�w hkg ] _ mBc3g9e3�«��cVm rV}"ts]]�¢�r �Zd tk]?� c x l r g w§�½r g ]�³Rr��&� h \ _ tk["w"] mBl ] � ]?\ mih [ � ³ c r mih \ j w h { h w"]D³�rT� ~®w h � _ ["���i]?w h \mBl ]Np h � � � ¡ c3g [ � h \�p&q9o�°Do'� �T� � �3 T�9�V��uÁ���3uÁ�3��uÁ�f §uÁ�3��u¦ §�3u¦ 3^§uÁ���3u�x c3g ]�¢�r �Zd tk] � rV\"wD�i] _ [ g�hkm�e �g ]zts]�{Vrn\ m ³Rr��&� h \ cVmil ] g&d"g�c _ ]?��� c3g �F~®] �·j"� u ¹ Wf�3  Ä ���

� l ]�w h � mih \ _ mBhkc \"�5r �­c \ j�mil ]?��] mBl"g ]?] �Zc w"]?� m ]?\�w mBc w h �Br d�d ]?r g5h \ � e � m ] � � mil r m r g ]�\ cnm �5]?tst� mig [ _ m [ g ]?w1u h \²� l"h _ l h \"� h w"]ZrV\�w c [ m � h w"]­r g ] h \�w h � mBh \ j [ h � l rV}"tk]y~Krn� h \ � e � m ] � �D� hkmil c \�t e©c \�]d"g�cVm ] _ mBhkc \4� m r m ] � u c3gDh \²� l"h _ l4c [ m � h w"]­rV\"w }£]zt c �*r g ] � ] g�j ]?wb~KrV� h \²³Rr m � e � m ] � � mBl r m;l rT{V]\ c _ c \ _ ] d�mDc x l"h ] g r g _ l'e���� q�\ rnw"w hkmihsc \�u _ cV�­d"g�c3�Zh �i]z�#x gicV� c [ m � h w"] � r e �i["}��i]� '["]z\ m t e ]z\�rV}"tk]_ cV�­d"g�c3�Zh �i]z� x gic3� � hkmil"h \1u'rn\"w _ c3�Zd"gic3�Zh ��]?� x g�c3� c [ m � h w"] c3g � hkmil"h \ � r e �i["}��i]� '["]z\ m t e ]z\�rV}"tk]_ cV�­d"g�c3�Zh �i]z��x g�c3� }£]zt c � � � l ]�w h � mih \ _ mBhkc \"�5r g ]�rnts� c�� [ g��'e­h \ _ rV��]?� c x�] � ] gij ]z\ _ e�c3d ] g r mBhsc \"� �¡ [ g�mil ] g��­cVg ]Vu�rV\�] j3g ] j3hsc ["� d"gic _ ]z�i��� l ] g ]?} e {3]z\"w c3g � _ rV\¶w h �BrV}"tk]�� c x m �Nr g ] g ] �ZcVm ]zt e�h �1w h � _ ["�i��]?wh \�o§] _ mihsc \�^ � � �

a ] g9m r h \br m�m r _ � �Zc w�]?� � r e c _z_ [ g­h \brn\ e c x mil ]?��]«x c3g�� � c x _ c3�­d�gic3�Zh ��] � ¡ c3g ]�¢�r �­d ts]Vu_ c \"� h w"] gImBl ]¶x c tst c � h \ j � gic�� rV\P� l"c3g �i] d ] gid ] mig r mihsc \��?u�� l"h _ l _ rV\ m r � ] d t|r _ ] h \Ã]�r _ l x c3gi�µ�

� aNcV�­d"g�c3�Zh �i]Fx g�c3�/c [ m � h w"]V��rµts] mim ] g } c3� } ~ ] �Áj�� u ]?ts] _ migic \ h _ � r h t c3g¶¿4c3g w � r _ g�c { hkg ["� �mil r m � l ]?\ g ]�rVw cVg�h \ m ] gid�g ] m ]?w _ rV\ g ]z�i["t m h \�["\�rV\ mih _ hkd r m ]?wb]�¢�] _ [ mihsc \��?u c3g r � d�c§c ±"\ jr mim r _ ��mBl r m&d"hsj3jne }"r _ � � c \«r�t h \"] c3g&g ] d tsr e �¯r � ]z�i�ir j ]

� aNcV�­d"g�c3�Zh �i]�x g�c3� � hkmil"h \1�Fr«�i[ g�g ] d�mBhÂmBhsc ["� _ c w�] d r m _ l mBl r m;� r h \ m r h \"�Dr l�h w"w"]z\ migih _ � tk]±"ts] c x �i]z\"� hÂmBh {V] h \�x c3g�� r mBhsc \­� hkmil"h \ mil ] d"gic3jVg r � w�r m r

� aNcV�­d"g�c3�Zh �i] x g�c3� }�]?t c �¶�)r&� hsg ] m r dDhs�Zd tsrV\ m ]?w h \"� h w"]�r m ]zts] d"l"c \"]���� hÂm _ l u c3g °¶]z\ � l"cV�­d �� c \ � � \ c �½� _ tsrV�i� h _ rnt c } � ] _ m � _ c w"] �­c w h ± _ r mihsc \ c x mBl ] a _ c3�Zd"h tk] g�mil r m)d ] gi�Zhkm�m ]?wDr mBg r d w c§c3gg�c [ mih \"] mic }£] d tsrV\ m ]zw h \ mBl ]�t c3j3h \ ¹ Wf V^ Ä ~®� l ] g ]z} eyhkm }�] _ cV� ]z� _ ts]?r g½mBl r m � e � m ] � ��] _ [ gihkm�ernts� c %�>'O�>PJ %)=���O�E£J mil ] _ c3�Zd"h tk] gB��� � l�c3�­d � c \ � � � g�c�� rV\ l"c3g �i]y�½rn� h \"�i] g�m ]?w h \ mBc©mBl ]� � � � �� _ c w"] c x mil ] a _ cV�­d"h ts] g ~ � hkmBl \ c _ l rV\ j ] h \ mBl ]�� c [ g _ ] c x mBl ] a _ cV�­d"h ts] g � u'tk[ gi�'h \ j[�\ mih t mil ]µ\"]�¢ m­g ] _ c3�Zd"h tsr mBhkc \ c x mBl ]yt cVj3h \ g�c [ mBh \"]Vu�� l ]?\ hkm _ g ]�r m ]?w+r mig r d w cPc3g�h \ mBl ]� � � � �� _ c w"] c x mil ]&t c3j3h \ gic [ mBh \�]D~®� hkmil \ c _ l rV\ j ] mBc¶mBl ]&� c [ g _ ] _ c w�] c x mil ]�t c3j3h \ gic [ mBh \�] ���� l ] � gic�� rn\ l"cVg �i] d tsr _ ]zw h \ mil ] _ c3�Zd"h tk] g �NrV� _ r d rV}"ts] c x g ] h \"��] g9mBh \ jDhÂm ��]?tkx h \ micDmil ] c } � ] _ m_ c w�] c x ��[ _?_ ]?�i� h {V] g ] _ c3�­d�h t|r mBhsc \"� c x mBl ] _ c3�Zd"h ts] g&hÂm �i]ztkxu£rV\"w mil ["�#�NrV� hkm �i]ztkx���[ g { h {nrV}�ts]��� l�h �½��[ j3j ]z� m � mil r m _ c3�­d�h ts] g � l r�{3]¶� c3� ]�� d ] _ h rnt d"gic }"ts] � � c x mBl ] hsg½c �&\1uRrV� _ c \"� h w"] g ]zw h \oP] _ mihsc \�� � �TX �

� rV}"ts]µ� � ����[ �­� r g�h�� ]z��� c3� ] d"g�c3d ] g�mih ]?�D� l"c ��] \ c \"�ir mBh ��x r _ mBhkc \ _ c ["tkw d�cVm ]z\ mih rVtkt e _ c3�Zd"gic ��Zh �i]�� e � m ] � }£] l r�{ hkc3g u�} e _ c3�Zd"gic3�Zh � h \ j _ c \�±"w"]?\ mBh rVt hÂm�e u h \ m ] jVgihkm�e u�r�{nr h tsrV} h t hkm�e u g ]�rntÂ� mihs� ] d ] g �x c3g�� rV\ _ ]Vu c3g _ c3g�g ] _ m \"]z�i� c x�r d"d t h _ r mBhkc \ � c x m �Nr g ]nu#] hkmBl ] g r _z_ h w"]?\ m rntst e c3g�h \ m ]z\ mihsc \"rVtst e3� � c

Å �

Page 36: Practical Architectures for Survivable Systems and Networks (Phase

��������� ÅÁÅ� � ��������������� ��� ������������� � ����� �!�"$#%'&$( )*&,+.-/%�&,+10324# )�&$+.-/%�&,+5062�# )*&,+.-/%�&,+10324#!87 2�9:%�!�;<9403&$= (>%?&$+@&$A�9�2403B/#,C (6%�&$+EDF0G94H�06=IC (>%?&$+E7�#KJ6&LD'C

MN����O��P� � ��Q � ��O ��R Q MN�:�4O��P� R O8��Q � ��O ��R Q MN����O��P� R O8�:�SQ � ��O ��R QT �8��� � O8� UWVX���P�<Y[Z\�8O^] ��_��:� R ��K`L��a>� ��b �� R � � ��� R �c� R � ���<����_,d�,� b �4�:] O � ����e�S�:���PV:�<�,���4O

� � Q�_K� R���R Q,]8�f��V �L`g�����:���h���P���$�:�����S�����ij����� kl���SdK���:����O��:��� UWV:V � O�� R �S���^� � ���S� b ����m UN����� � V:�<� � � R ��`8�������n���8���<Q�

�oR �S� R � � � R �<�^� � ������� ���N���:� � � V:�\O8� R � �<�UW����� � V���� � � R p � R �:������� � � R �h�<Y p �S��Q����<�c� ��R Q������S����� UN����� � V:�<� � � R.q � Q ]�r\stkvu�w

�<����� � V:�<� � � R ����� � � Vf� ��R �<����� � V:�<� � � R Vf�8O8� � R O8����� ��R ��Oyx � ��_ ��R��R �S�:Q�� � �e` ���$�:����� ��R QF��`8�e�S�:�F� q T u8��w

k � O�O8���:xt�<�S� p � R �:������� � � R �<Y �z�S�<{�� R _���S� ��R Q���Y uL��� � ���S� � � R ��Y/� � O�O8���:xt�<�S�|}���~� R Oyrjstkvu |}���'� R Oyrjstkvu YG���� T u���� R �:�ex��� b����� � �:��� ����� � �:��� ���$�:����� � � R �

MW�f�exh��� b���R Q p � R �:������� � � R �<Y �z�S�<{�� R _���S� ��R Q���Y �h�<�8�S���S�\��Y V:��`L�8�S�����8�����S��]K���S�:xt�<������m R �f�exh��� b ����Y��exh����� b ��`L�tx � ��_ ��R ��_�� T u�mrW� R � �<���t�<Y[����� � � Vf� � � ����� � �S�<� � � R �<Y�����xh�:�

���S�<���8V:���^���?`��:���T �$�:����� ��R Q p � R �:������� � � R �h�<Y T u��L` �����?xh��O T ug���<Y��ext�<�S��m T u�� R O8����� ��R ��OgYG������`8�e�S�:� � R ���8��_��� ��� �4Og�,�����S� �z�S�<{�� R a>_��������4O T u�m x � �S_ ��R _��<��O8xt�<�S� �

�������$�:� ��R Qc�K` Y3�<�����S�N� � Vf����O ��R Q�Y3�<�������� ��� � ���:Q��O ��������S� R Vf�m8_��<��O8xt�<�S������8V:���S���4� �,�?xN�t���N�S�<�$�<���<Q�

�j�<��O8xh����� � � ����� R �<����`FQ� R ���S�<����O sh�Og_,�<��O8xh������O8�4� � Q R �oR ���:� R ���^�,��xh�:��:����Vf���S���F�<Q R �f� � Vj��� � R O � �c�����:�c� R ����� � � R m � �S�S�:Q�������� � � � ����<�S_��:� ��R ���:��YG�:�S� R Vf��m �W�<��O8xt�<�S�\���S�<{�� R _�����������m� � ����� R �<���,��xh�:��a i R �S��V:� � �:���<�����WY3�<�����S��m�8� � � � �e`�Q�� � ��V�_���� �oR �S�:� R �<� ��R ������YG����� R Vf�

�oR � � O8� kl�<� � V � �����t�� �oR �S�:� R �<�^�$��xh�:�P��������� � �4�:]� R � � ��� R �c� R � ��V�V � O8� R �S������Vf�S� ��� � ���$��Oy���S��� b ���S��]

i p u,�?���<��������`cY3� � �����S���

Å �

Page 37: Practical Architectures for Survivable Systems and Networks (Phase

h tkts["� mBg r m ]���[ _ l _ cV�­d"g�c3�Zh �i]z�?u mBl ] m rn}"ts]DrVtk� cZh \"w h _ r m ]?� d£c �i� h }"ts] _ c3�­d�gic3�Zh ��]?� � � l ] mBl ] g�mil ] eh \f{ c tk{V] �­c w h ± _ r mihsc \ ~ m r �­d ] g�h \ j'��c3g \ cnm � mBl r m _ rV\ c _?_ [ g x gic3��c [ m � h w"]Vu3x g�c3� � hÂmBl"h \1u c3g x gic3�}�]?t c �¶u3x c3g ]�r _ l�g ] d"g ]z�i]z\ m r mBh {3]¯t|r e ] g c x£rV}"� mBg r _ mihsc \ � � l ]&w h � mBh \ _ mihsc \"�¾r g ]I\ cVm rVtÂ�½r e � d"g ] _ h �i]V�¾rd ]?\"] mBg r mBc3g�� r e _ c3�Zd"gic3�Zh ��]Ix gic3� c [ m � h w"]nu§}"[ mNc \ _ ] l r�{ h \ j;d ]?\�] mBg r m ]zw1u h � mBl ]z\ h \ d�c � hÂmBhsc \ mic_ cV�­d"g�c3�Zh �i]�x g�c3� }£]zt c � c3g x gic3� � hÂmBl"h \ � � l [��?u c \"] m�ePd ] c x _ c3�Zd"g�c3�­h �i] � r e }�]N[��i]?w mic ]z\�rV}"tk]rV\ cnmBl ] g?� ¡ c3g¾mil"h � g ]�rV� c \1u mil ] m rV}"tk] _ l r g r _ m ] g�h�� ]z� c \"t eDmBl ] d�gihs� r g9e��Zc w"]?� c x _ cV�­d"g�c3�Zh �i] � ¡ c3g]�¢�r �Zd tk]Vu)rÃ["�i] g ]z\ m ] g�h \ jÃmBl�gic [ jVl r g ]z� c [ g _ ]­r _?_ ]?��� _ c \ mBgic t d r _ � r j ]��i[ _ l rV�Dp¯� a ¡ c3gDa �&�� c3d o§] _ g ] m u cVg�mBl�gic [ jVl r��i[ d ] g ["��] g�� ] _ l rV\ h � � u1rn\"w j r h \ h \ j r d�d r g ]z\ m t e tk] j3hÂmBhs� r m ]¶r _?_ ]?�i� micmBl ]�["\�w"] g t ePh \ jZc3d ] g r mBh \ j � e � m ] � � r e mil ]?\�}£]�rV}"tk] mBc ["\"w"] gi�Zh \"]¶} cVmBl�c3d ] g r mBh \ j ��� e � m ] ��h \§�m ] j3gihÂm�e ~ _ c3�Zd"gicV�­h �i]Nx g�c3� � hÂmBl"h \ � rV\"w�w�r m rV}�rn�i] h \ m ] j3gihÂm�e ~ _ c3�Zd"gicV�­h �i]Nx g�c3� }�]?t c � h x mil"gic [ j3lmBl ] c3d ] g r mBh \ j � e � m ] ��� u�]�{3]z\ mil"c [ jVl4mBl ] c3gihkj3h \�rnt _ c3�Zd"gicV�­h �i] h �¶x gic3� c [ m � h w"] � o hs�Zh t|r g t e u�r� c x m �½r g ] hs�Zd ts] � ]z\ m r mBhkc \ c xNrn\�]z\ _ g9ePd�mBhkc \4rnt j3c3g�hkmil"� c3g�c xNr _ g�ePd�mic3j3g r d"l"h _�_ l ] _ � ��[ � ["��]?wrV��rn\ h \ m ] j3gihÂm�e �i]�rnt _ rn\©}£] _ c3�Zd"gicV�­h �i]?w«} e � cV� ] c \"] j r h \ h \ j r _?_ ]z�i� mic�mBl ];["\"]?\ _ g�ePd�m ]?w h \§�x c3g�� r mihsc \ h \ � ] �­cVg�e­c3gImBc�mBl ]¶]z\ _ g9e§d§mBhsc \ � ] _ l rn\ h � � hkm �i]ztkxu�r m r�t c �5] g tsr e ] gIc x¾rV}"� mBg r _ mihsc \ ��0["��] g ]�¢ d t c3hkmih \ j rn\Ãq�\ m ] g \"] m � gicVmic _ c t g�c [ m ] g {P["ts\"] g rV} h t hÂm�eZ� r e h \ hkmih rVtkt e }£]¶rV}�ts] mBc _ c3�Zd"gic ��Zh �i]&r¶� e � m ] � x g�c3� � hkmil"h \ mil ]&t c3j3h _ rVt§t|r e ] g c x hÂm ��\"] m � c3g��'h \ j � c x m �Nr g ]nu§}�[ m �i["}"��]� '["]z\ m t e­� r e_ g ]�r m ]�x®[ g�mil ] g _ c3�Zd"gic3�Zh ��]?�Nx g�c3� c [ m � h w"] cVg }£]zt c � � � l ] � l"c3�Zd � c \ _ c3�Zd"h tk] g � g�c�� rV\ l"c3g �i] h �r d r g�mih _ [�t|r g t eªh \ m ] g ]?� mBh \ j _ rn�i]Vu¾}£] _ rV["��] hkmD� r e \ cVm \ c3gi� rVtst e }�] mil"c [ jVl'm;c x&rV� _ cV�­d"g�c3�Zh �i]x gicV� }�]?t c � h x mBl ] _ c3�­d�h ts] g;h �;\ cVm [�\"w"] g � mic§c w mBc }�]Ã� c3� ] mil"h \ j«mBl r m�h �Fw�] d ]?\"w"]zw�[ d£c \ x cVghkm � _ cVgig ] _ m }�] l rT{ hkc3g?� q�\"w"]z]?w1u hkm;h ��r«{V] g9e }�rVw d�c t h _ e©mic ["�i]yrV\ [�\ mig ["� m � cVg�mBlfe _ c3�­d�h ts] gDmicj ]z\"] g r m ]­rV\ cVd ] g r mih \ j � e � m ] � u rn\"w mil ] g ]zx c3g ] mil ] _ c3�Zd"h tk] g�� ["� m }�] _ c \"� h w"] g ]zw ��}�]?t c � � ~ cVg]?tk�i] mil ]Iw"] d ]?\�w"]?\ _ ] � ["� m }�] _ c \"� h w"] g ]?wZrV� r#{ hsc tsr mBc \ c x�t|r e ] g ]zw mig ["� m � cVg�mBl�h \"]z�i�?u§rV� h \ � � � ���q�\"w"]z]?w1u mBl ]�]?\ mBhkg ]#� c x m �Nr g ]�w�]z{3]zt c3d�� ]z\ m½d"gic _ ]z�i� h �Nr l [ j ] c3d"d�c3g�m ["\ hÂm�e x c3g _ c3�Zd"gic3�Zh � h \ j¶mBl ]h \ m ] j3g�hkm�e c x mil ] g ]?��["t mih \ j � e � m ] � ~ h \ m ]?\ mBhkc \�rVtkt eZc3g r _?_ h w"]z\ m rVtkt e����¡ gic3�0mil ] m rn}"ts]nun�5] c }"�i] g {V] mil r m r�� e � m ] � � r e }�] h \ l ] g ]?\ m t e _ c3�Zd"gicV�­h � h }�ts]Vu h \�r#{nr gih ] m�eDc x

�Nr e � � � l ] d [ gid�c ��] c x�� e � m ] � w"]z� hsj \ h ��\ cVm mic¶� r � ] mBl ]¯� e � m ] � _ cV�­d tk] m ]?t e \ c \ _ c3�Zd"gicV�­h � h }�ts]~®� l�h _ l²h � hs�Zd£c ��� h }"ts] � u�}"[ m�g r mBl ] g�mBc d�gic { h w"]�� c3� ]FrV�i��[ g rV\ _ ] mBl r m�mBl ] �­c � m t hs� ]zt e rV\"w �Zc � mw"]�{Vrn� m r mBh \ j _ c3�­d�gic3�Zh ��]?� r g ] d"g�c3d ] g t e rVw"w g ]?���i]zw } e w"]?� hsj \"�zu�r g _ l"hÂm ] _ m [ g ]?�zu§w"]�{3]zt c3d"� ]?\ mNd"gic �_ ]z�i��]?�?u"rV\"w cVd ] g r mihsc \�rnt d"g r _ mBh _ ]?�zu�rn\"w � h x _ c3�Zd"g�c3�­h �i]z��w c�c _?_ [ g � mBc }�]�rV}"tk] mBc w"] m ] gi�Zh \�]mBl ] _ rn["�i]z��rV\"wª]�»�] _ m �?u mic t hk�­hÂm½mBl ];\"] j r mBh {3] _ c \"��]� '["]z\ _ ]z�?u�rV\"w mBc­m r � ]Fr d"d"g�c3d"gih r m ]Dr _ mBhkc \"� �� l ["�?u hkm&h �¯w�]?� hkg rV}�ts] mBc­d"gic { h w"]D["\"w�] g t ePh \ jZ� ] _ l rV\ h � � � mBl r m r g ] h \ l ] g ]?\ m t e w h� _ ["t m&mic _ c3� �d"g�c3�­h �i]nu§rn\"w mic }"[ h tsw _ c \"� h � m ]z\ m t eZc \ mBl"c �i] � ] _ l rV\ h � � � ��º \ mil ] cnmBl ] g5l rn\"w1u h \ mBl ] d"g ]z�i]?\ _ ]c x ["\"w"] g t e§h \ j�� ] _ l rV\ h � � � mBl r m r g ] h \ l ] g ]z\ m t e _ c3�Zd"gicV�­h � h }�ts]Vu hkm&� r e � mBh tkt1}�] d£c ��� h }"ts] mBc ["��]´5e � rn\ mih \"]���t hs� ]I� mBg r m ] j3h ]z� mic�� r � ] mil ] l"hsjVl ] g ��t|r e ] g�� ] _ l rV\ h � � � ts]z�i� _ c3�Zd"g�c3�­h � h }"ts] � ( c �N]�{3] g u³Rr��&� mBl r m½d ] g��­hÂm _ c3�­d�gic3�Zh ��] c x mil ]�["\�w"] g t ePh \ j t|r e ] g �Ir g ] h \ l ] g ]?\ m t e�g�h � �'e ["\"tk]?��� mBl ]#]z»£] _ m �c x �i[ _ l _ c3�Zd"g�c3�­h �i]z� _ rV\µ}£]�� mBg�h _ m t e _ c \ m r h \"]zw �

(*) � � �����),������ ���5� 9,��P� � �5( �����5( 9�§�)�

� gicVm ] _ mBhsc \�r j r h \�� mImBl ] mil"g ]z]Dx cVgi� � c x _ c3�Zd"gic3�Zh ��]�\ cVm ]?w h \�o§] _ mBhkc \²� � W�� _ cV�­d"g�c3�Zh �i]�x gic3�c [ m � h w"]Vu _ c3�Zd"g�c3�­h �i]¾x g�c3� � hÂmBl"h \1u�rV\"w _ c3�Zd"g�c3�­h �i]¾x g�c3� }�]?t c � � r g ] g ]zx®] gig ]zw mic¯h \ mBl"h � g ] d�c3g9mrV� ��� � � � � � � � ���� � � � � � � � rV\"w � �� ��� � � � � � �'g ]z� d ] _ mBh {V]?t e � mil r m h �?u d"g�c { h w h \ j¯c [ m � h w"]5}"r gig�h ] g

Å �

Page 38: Practical Architectures for Survivable Systems and Networks (Phase

w"]�x®]?\"��]?�?u h \ m ] g \"rVt1w"]�x®]?\"��]?�?u£rV\"wµw"]�x®]?\"��]?� mBl r m¯d"g�cVm ] _ m ["\"w�] g t ePh \ j�� ] _ l rV\ h � � �?u g ]?� d ] _ mih {3]zt eV� �q�\ j ]z\"] g rVtvu�rVtst mBl"g ]?] m�ePd ]?� c x d"g�cVm ] _ mBhkc \yr g ]�\"] _ ]?���Br g9e3� � r gihkc ["�½r d"d"gic r _ l ]?�¯r g ] _ c \"� h w"] g ]?w

h \ aNl r d�m ] g �N�§u§ §uPrV\"w­� � ¡ c3g mBl ] d [ gid�c �i]z� c x mBl�h � _ l r d�m ] g u � ["� m r¶x®]�� h tkts["� mBg r mBh {3]½]�¢"r �­d tk]?��r g ]j3h {3]?\ l ] g ]Vu g ]?tsr mBh \ jDmic rDx®]�� c x mBl ]#t|r e ] g � c x)rV}"� mBg r _ mihsc \­� l"c �&\ h \ � rn}"ts]�� � � � �#� h \"w h _ r m ]?w­} emBl�h �N��[ �Z� r g9e u§� c3� ] c x mil ] m ] _ l \ h P[�]?�¯r g ] P[ hkm ]#w h »£] g ]?\ m x gicV� c \"] _ rn�i] mBc rn\ cVmBl ] g u�rVt mil"c [ jVlcVmil ] gIm ] _ l \ h P[�]?��r g ] �Zc3g ] j ]z\"] g�h _ rVtst e r d�d t h _ rV}"tk] �

� � � E �£H®Q % H J � � ¨ c3� r h \�r g _ l"hkm ] _ m [ g ]z� d"g�cVm ] _ mBh \ j � e � m ] � �#x g�c3� mBl ] hsg ["�i] g �?u£± g ]��½rVtkts� d"gic �m ] _ mBh \ j�c \�]­� e � m ] � x g�c3� rV\ cVmil ] g u rV[ mBl ]z\ mih _ r mBhkc \ � ] _ l rV\ h � � � d"g ]z{3]z\ mBh \ jªd ]z\"] mig r mihsc \��r m w h »�] g ]?\ m tsr e ] g �?u&["��] c x¶]?\ _ g�ePd�mihsc \bx c3g _ c \§±�w"]?\ mih rVt hkm�e rV\"w h \ m ] j3g�hkm�e c x h \�x c3gi� r mihsc \mig rV\�� �Zh �i� hsc \�u�]?tk] _ mBgicV� r j \"] mih _ � l"h ]ztsw h \ j

� � J %�E �£H®Q % H J � � _ c3�Zd"h ts]�� mBhk� ])rV\"w g ["\§� mihs� ] _ l ] _ � �¾�i[ _ l rV��} c ["\"w�� _ l ] _ � � rn\"w m�e§d ] _ l ] _ � �mic��Zh \ hk�­h�� ] mil ];]�»�] _ m � c x�] g�g rV\ m�d�gic3j3g r � �?uRx rV["t m¯mBc ts] g rV\ _ ]Vu h \ m ] j3gihÂm�e _ l ] _ � � mBc d�g ]z{V]?\ mrn\"w w�] m ] _ m � gic�� rV\ l"c3g �i]z�?u¾[��i] c xN]z\ _ g9ePd�mBhkc \�x cVg _ c \�±�w�]?\ mBh rVt hÂm�e rV\"w h \ m ] j3g�hkm�eªc xN� mBc3g ]?wh \�x c3g�� r mihsc \�u �­c \ hkmBcVgih \ j­c x d"g�c3j3g r � }£] l r�{ hkc3g#mic w"] m ] _ m¶�­h �i["��] c3g rV}�] g�g rV\ m � e � m ] � c3d �] g r mihsc \

��� J'%)>'Q ��H Q %)HKJ � � ["�i] c x1��] _ [ g ] � ] g \"]zts� mic¶d"g ]�{3]?\ mNl"hsj3l ] g �¼t|r e ] g _ c3�Zd"gicV�­h �i]?�zu mBg ["� m � c3g�milfecVd ] g r mih \ j � e � m ] � ��rV\�w l"hkj3l � h \ m ] jVgihkm�e#l r g w��½r g ] mic ��[ d"d�c3g�m _ g�hkmBh _ rVtf� c x m �Nr g ]�x®["\ _ mihsc \"rVt hÂm�e u[��i] c x � d ] _ h rVtÂ� d [ gid�c ��] l r g w��Nr g ]y~®] �·j"� u _ c � d"gic _ ]z�i� c3g �¶rV\�w _ g9e§d§mBc3j3g r d"l"h _ ]?\ j3h \"]z� �¯mic r h wtk]?��� mBg [�� m � c3g�mil'eµl"hkj3l ] g ��tsr e ] g � e � m ] � �

(*)�� �N�����������5� ����6&�

o c3� ] c x mBl ] � rV\ e � m r j ]?� c x5� e � m ] � w�]z{3]zt c3d�� ]z\ m rn\"w²["�i]�w"[ g�h \ j � l�h _ l�gih � � � � r e r gih �i]�r g ]t h � m ]?wµ}£]zt c �¶u�rnt c \ j � hkmil r�x®]z�0]�¢"r �­d tk]?� c x¾� l r m��Zhsj3lfm¯j3c � gic \ j ~KrV\"w�u h \ �Zc � m _ rn�i]?�zu£� l r ml rV� j3c \�]Z� g�c \ j«h \ mil ] d rV� m ��� � l"h ��t h � m ��[ �Z� r g�h�� ]?�D� c3� ] c x mBl ] � r h \ mil"g ]?r m � � oP] _ mihsc \ � � �j3h {3]?�&]�¢"r �­d tk]?� c x � d ] _ h ± _ h tkts["� mBg r mBh {3] _ rV�i]z� �

8DQ�E � L >�� =¶H J S¸:)>y= !�=zST>�� %�>���>§L®ERO � >§J�SFO)Q�E�3>§=?= h \f{ c tk{3] d ] c3d tk]�r m ]�r _ l � m r j ]Vu"rn\"wÃr g ]h tkts["� mBg r m ]zwÃ} e�mBl ]�x c tkt c � h \ j ]�¢�r �Zd ts]z�?�

� � !�=zS�> � 3E£J'3>'O)S"�)<�L H �f<�S¸H®E£J � h \�r d"d"gicVd"gih r m ]©["��] c x m ] _ l \ c t c3jVe � l ]z\ mBl ] gih � � ���5] g ]r _ m ["rVtst e­mic§c�j3g ]�r m uRrV\"w�rV}"��]?\ _ ] c x _ cV�­d [ m ] g�h�� r mBhkc \ � l ]?\ hkm � c ["tkw l r�{3]D}£]z]?\«]z�i��]?\ mBh rVt

� M�> � � H®Q¸> � >§J�S¸= %)>��¾J H S¸H®E�J � ] gig�c \"] c ["�?u h \ _ c3�Zd ts] m ]nu"rV\"w h \ _ c \"� h � m ]?\ m¯g ]� '[ hsg ] � ]?\ m �� �0E&%�>PLK= �½x rVts��];rV���i[ �Zd�mihsc \"�#rV} c [ m¯mBl ] d�l'e � h _ rnt � c3g tkw1u mil ] cVd ] g r mih \ j ]?\f{ hsgic \ � ]z\ m u1rn\"wl [ � rV\y}�] l r�{ hsc3g

� � !�=zS�> � %�>P=�H���J � x®["\"w�r � ]z\ m rVt �Zh � _ c \ _ ] d�mihsc \"�&rn\"w�w�]?� hkj \óRr��&�� $ �4O L >��4>PJ£S�<�S¸H®E£J � d"g�c3j3g r � }"[ j �?u c3�Zh �i� hsc \��?u�rV\�w � gic�� rn\ l"c3g �i]z� _ rV["� h \ j ["\�rV\ mBh _ hkd r m ]zw]�»�] _ m �

� &J/a���1+B&`21&�35=�LK���21/1>?�Q)*=+B)�>1+B/?=�� �:35& + �*& /:30�*21)�35' !J'H35/1=2:35=�V-���35/?+B/1=���� �?,=+B)*>1+B/1=�� �<35;��&b,/a�*�1�"�1)*+B-435)*I$-��Q35/1+B/1= ,56���=+B)�>1+B/?=��1K��,3QML,+B>A%�,/?672?&�+B,/A !+ �*�G+ �*&",5���1��)!-��Q35/1+B/1=&������/1>1,=+B)�>?+B/1=���+B&"+B/��*)�,�>121%���>@35&V35/G+B/L����)*-��Q>?+H30���9%�,/1%����?�!Z /1��+ ���?�Q)!,2?�*&�+B>1�$/1,)"8Y��'B,� $K812?�!)�30���1��)!+B/��*��)�/:35'(#

� �

Page 39: Practical Architectures for Survivable Systems and Networks (Phase

� ����O O�ERQTS�= !�=zST>�� = � d�c§c3g d"g�c3j3g r �­�Zh \ j t|rV\ j [�r j ]z�?u3x rV[�t m�e _ c3�­d�h ts] g ��rn\"w�w"]z}"[ j3j ] g �zu�rn\"w�Zh ��ts]?rVw h \ j w"]�{3]?t c3d"� ]?\ m�mBcPc tk�¾� l"c ��]I["�i] �Zhsj3lfm d ] g��­hÂm mBl ]Iw"]z{V]?t cVd"� ]z\ m c xR�N]?r � � e � m ] � �

� A5>§=�S¸HKJ ��<�J % ��>'Q�H � 3<�S¸H®E�J � h \ _ c3�­d ts] m ] m ]z� mBh \ j u h \ _ cV�­d tk] m ] c3g ] g�gic \�] c ["�&{3] gih ± _ r mihsc \� � �£E�L���STH E�J ����t c3d"dfe�� r h \ m ]z\�rV\ _ ]Vu �­h � _ c \ _ ] h {3]zw � e � m ] � [ d"j3g rVw"]z�?u h \ migic w"[ _ mBhsc \ c x½\"]z�³�rT�&� h \�r mim ] �­d§m � mBc ±�¢ c tsw ³Rr��&�

� �£ST<���J�<�S¸H®E�J � h \�x®]?rV� h }"ts]�]�¢ d rV\"� hsc \ c x�r � e � m ] � }£] e3c \�w hÂm � h \ hkmih rVt g ]� '[ hsg ] � ]?\ m � ~®] �·j"� u}�] _ rV["��]�� c x m �½r g ]D}"t c r m u�t c �i� c x � ] eµd ] g � c \"\�]?tvu c3g ["\"rT{nr h t|rV} h t hÂm�e�c x _ c3�Zd r mBh }"ts] l r g w§�½r g ]hk�­d ]?w�]?�I[ d"jVg rVw"]z�¯rV\"w g ] migic ± m � �

� �Ã>�3E���� H =�=�H®E�J � d"g ] � r m [ g ] g ] �­c {nrVt c x�r d"g�hs� r g�e�c3g }�r _ � [ d x r _ h t hkm�e u l"h w"w"]z\;w"] d ]z\"w"]?\ _ ]c \­rn\ c tsw�{3] g � hkc \ mBl r m h ��\ c t c \ j ] g r�{nr h tsrV}"tk]N}"[ m mil r m h � g ]� '[ hkg ]?w«~ ] �Áj�� ufx c3g _ c3�Zd r mBh } h t hkm�e��

8DQ�E � L >�� =;HKJb= !�=zST>�� ERO�>PQ¸<�STH E�J+<�J'% �)=?> h \f{ c tk{3] d ] cVd ts]¶rV\�w�]�¢ m ] g \�rVt�x r _ mic3g �zu�rV\"w�r g ]h tkts["� mBg r m ]zwÃ} e�mBl ]�x c tkt c � h \ j ]�¢�r �Zd ts]z�?�

� � <"Q %�C;<"Q¸> �4<"L�� �)J'VS¸H E�J u"w"["] mic�

� \f{ hkgic \ � ]z\ m rVt�x r _ mic3g �&��[ _ l rV�¯t hkj3lfm \ h \ j u�]?r g�mil '[�r � ]?�?u£]�¢ mBg ] � ] m ] �Zd ] g r m [ g ]z�?uR]?tk] _ �mBg�c3� r j \"] mBh _ rV\"w cVmBl ] g�h \ m ] g x®] g ]z\ _ ] h \ _ ts[�w h \ j _ c � �­h _ g rVw h r mBhkc \Frn\"w­��["\"� d£cVm r _ mBh { hÂm�e urV\ hk� rnts��~®� l r gi� �?u g r m �zu�rV\"wµ� '[ hkgig ]zts�&r g ] h \ _ ts["w�]?w h \ mil ] _ rV��] l"h � mBc3g�h ]?�zu§x c3g ]�¢�r �­d ts] �rV\"w � rV\ e \�r m [ g rVt�w h �BrV� m ] g � � ¡ cVg�g ] _ ]?\ m ( c ["��] m ]?� mihs�Zc \ e�c \Z� c3� ] c x mil ] gih � � � c x�p ¡h \ m ] g x®] g ]z\ _ ]nu£��]?] � � � � � � � ��� � �������� � � � � � � � ��A ��� ��� � ��� � � � � �?�J � � ��� � � ��� $ � � � �� � ��& � � �� � � � ��� l'm�mBd �¦¥3¥��I�I� �·l"c [��i] �·j3c {�¥ � ] _ ¥ l ]?r gih \ j � ¥nXf^¸�9^V�¸�� l��ÁlfmB����� o e � m ] � �Dw"]z{V]?t �c3d ]?w h \ mBl ]Fx cVgi� ] g o c { h ] m ¬¯\ hsc \«�N] g ] d"g ]z{ hsc [��it e w h � _ [��i�i]zw²} e©� ]z\"] g rVt�o _ l �5] hÂm � ] g~ lfm�mBd �¦¥3¥ �9e r � _ c3� ¥ g x �½� � ] _ �·lfmB�����

� c �i� c x¾]?tk] _ migih _ rVt d£c �5] g�

aNc3�Zd£c \"]?\ m¯� rntkx®["\ _ mBhkc \1� r j3h \ j u mBg rV\"� h ]?\ m }�] l r�{ hsc3g u c3g&h \"rVw"]� '[�r m ]¶w"]?� hsj \� ��E �vS�CF<"Q¸> �4HK= ��>P:�<���H ERQ �©x c3g ]�¢�r �­d ts]Vu&w"[�] mBc d"g�c }"tk] � � h \ mil ]ª� e � m ] � w"]z{V]?t c3d"� ]?\ md�gic _ ]?���?uRrV�&\ cnm ]?w�rV} c {3]

� � � � <�J ��>P:)<���H®ERQ�H J4= !�=�ST>�� �)=?> uf� l ] mil ] g5h \�� e � m ] � c3d ] g r mBc3g �?uPrVw �Zh \ h � mig r mic3g �zu3� m rn»¾u[��i] g �?u c3g ["\��i["� d ] _ mBh \ j } e � m rV\"w"] g �zuRx cVg ]�¢�r �Zd ts]nu h \

q�\"� m rVtkt|r mihsc \1� hk�­d"g�c3d ] g _ c \�± j [ g r mihsc \�u h \ _ c3�­d r mBh }"ts]�{3] g � hsc \"�zu5] gig�c \"] c ["� d r g r � ] m ] g�i] mimih \ j �zu c3g t h \ � r j ]�] gig�c3g �

� h �i["��] c x mBl ] c {V] g rntst1]z\'{ hkgic \ � ]?\ m¯c3gImBl ] _ c3�Zd [ m ] g � e � m ] � �?u h \ _ ts[�w h \ j� ¬�\ h \ m ]z\ mihsc \"rVt �Zh ��["�i]�~ h \ _ tk["w h \ j [�\ mihs� ]?t e ["�i] � �&]?\ mig�e�c x hs�Zd"g�c3d ] g&h \ d [ m �?u �­h �9�h \ m ] gid�g ] m r mBhkc \ c x c [ mBd [ m �zu c3g ]�¢§] _ [ mBhkc \ c x mil ]�� gic \ j x®["\ _ mBhkc \

� q�\ m ]z\ mihsc \"rVt �Zh ��["�i]n� d ]?\"] mBg r mBhkc \ } e ["\"rV[ mBl�c3gih�� ]?w cVg ["\ h \ m ]?\�w"]?w ["��] g �zu �­h �i["��]} e rV[ mil"c3gih�� ]zwµ[��i] g �?u h \��i] g9mBhkc \ c x � gic � rV\ l�c3g ��]?�?u c3g x g rV["w

� l ]FtsrV� m �i["} _ r m ] j3cVg�e � h \ m ]z\ mBhsc \�rVt �­h �i["��] � g ] d"g ]?�i]z\ m ��r d r g9mBh _ ["t|r g � c3gig�h � c3� ]Fr g ]?r c x_ c \ _ ] g \ªrn\"w h � _ c \"� h w"] g ]?w h \�o§] _ mBhsc \«^ � � �

�TÅ

Page 40: Practical Architectures for Survivable Systems and Networks (Phase

(*)�� �N(*��� � ���!�� ,N� � ������� 9�'�"���R�)�

¿ ] _ c \"� h w"] gDl ] g ] � ["� m rµx®]�� h tkts["� mBg r mBh {V] d"g�c }"ts] � � mil r m�l r�{3]�}�]?]z\4]z\ _ c [�\ m ] g ]?w h \ mil ] d rn� m u�i[ j3j ]?� mBh \ jªmBl ] g r mBl ] g�d ] g {nrV� h {V]Ã\�r m [ g ] c x mBl ]Ã�i[ g { h {nrV} h t hkm�e²d"g�c }"tk] � � � hkmil � rV\ e w h {V] g ��]_ rn["�i]z�#rV\�w�]�»�] _ m � �� l ]I± g � m �i]�{3]?\ hkm ] � ��t h � m ]?w�}�]?t c � h \f{ c tk{V]?w � rV��� h {3] c [ m r j ]z� migihkj3j ] g ]?wZr _z_ h w�]?\ m rVtkt e } e t c _ rVt

]z{V]?\ m �zu�]?r _ l­c x£� l"h _ l _ c3�Zd"gicV�­h �i]?w c {V] g rntst�� e � m ] � rn\"w�\"] m � c3gi� ��[ g { h {Vrn} h t hkm�e3� � l ]&] hkj3lfmBl �NrV�mBg�hsj3j ] g ]zwÃ} e rF� h \ j ts] l [ � rV\y] g�gic3g u"}"[ mImil ]¶]z»£] _ m � d�gic3d r j r m ]zw mBl"g�c [ j3l"c [ mImBl ]Do§rV\ ¡ g rV\ _ h � _ c´ r e � g ]�r � � l ]­\ h \ mBl²h \f{ c tk{V]?w ryt c _ rVt c [ m r j ] mil r m �NrV� '[ h _ � t e _ c3g�g ] _ m ]zw1u }�[ m � l"c �i]­rnx m ] g �]z»£] _ m � _ c \ mBh \P[�]?w mBc­d"gicVd r j r m ]Dx cVg#� rV\ eyl"c [ g � � � l ]?�i] _ rV��]?� h \'{ c tk{V]?w l [ � rV\«x r _ mBcVg ��rn���5]?tstrV� cVmil ] g _ rV["�i]z� �

� M�8 J�>'S)3E�L L <"O =?> � º \y^V  º _ mBc }£] g �T�3�VX�u mil ]#�#p � �#\"] m r _z_ h w�]?\ m rVtkt e � l [ mIhkm �i]?tÂx�w c �&\j t c }�rntst eV�)aNc tstsr d ��]VunrV\�rVt e � h �zu3rV\"w g ] _ c {3] g9e;mic§c3� rn} c [ m � l�c [ g � � � l ] d"gic }�ts] � �NrV�¾w�["] mBc rl r g w��Nr g ]½w"]?� hsj \ cV�­h �i� hkc \Ã~ mBl ]&rn}"�i]z\ _ ] c x d r gihkm�e _ l ] _ �Ph \ j¶h \ � ] �Zc3g9e"� u l r g w��Nr g ]½x r h ts[ g ]?�~ mBl ] _ c ]�¢ h � m ]z\ _ ] c x m � c } c3j [��5{3] g � hsc \"� c x�r;\ c w"]�� m r m ["� � ]z�i�Br j ] g ]?�i[�t mBh \ j x g�c3�*� ] �­cVg�e] gig�c3g � � u&rV\"wbrV\ c {3] g t e j ]z\"] g�c ["�Ãrnt j3c3g�hkmil"� x c3gZj r g }�r j ] _ c tkts] _ mBhkc \ c x�� m r m ["� � ]z�i�Br j ]?� �� r _ l \ c w"] h \ mBl ]D\�] m � c3gi� }�] _ r � ] _ c \ m r �Zh \�r m ]?w�u � ] �Zc3g�e�c {V] g ³ c �N]zw1u1rV\�w mil ]¶\"] m � c3g��}�] _ r � ]�["�i]zts]?��� �

� $ J£ST>'Q�J�>'S =?>'Q"��H 3>²E���ST<��R>P= � º \²^VWZ� d"g�h t��T�3�f Pu£q�\ m ] g \"] m �i] g { h _ ] d"g�c { h w"] g ��t c � m _ c \ m r _ m� hÂmBl \"]�r g t e rVtktR¬ � o � q�\ m ] g \"] m }"r _ � } c \�] c3d ] g r mBc3g � � ���½r g ]?��["t m u � [ _ l c x mil ]#q�\ m ] g \"] m �NrV�w h � _ c \"\"] _ m ]?w1u§� c3� ] d r g�m ��x c3g ^VX �Zh \'[ m ]?�?uP� cV� ]&x c3g rn�5t c \ j rn�½W l�c [ g � � � l ] d"g�c }"tk] � �NrV�r mimBg�h }"[ m ]?w mBc � ��q � ] m � c3g�� oP] g { h _ ]?� h \ � _ ��]?rV\1u �#hsg�j3h \ h r²~®�I�I� �·� r hv� \"] m � u � l�h _ l4j rT{V]o d"gih \ m rn\"w cVmBl ] g }�r _ � } c \"] d"gic { h w"] g � h \ _ c3g�g ] _ mDgic [ mBh \ j m rV}"tk]?�zu mBl ] g ]?�i[�t mDc x � l"h _ l �NrV�mil r m � �#q��½rV��³ cPc w"]?wF� hÂmBlFmBg r _ � q�\ZrVw�w hkmihsc \1u mBl ]Iq�\ m ] gB� q a w hkg ] _ mBcVg�eFh \ _ cVgig ] _ m t e t h � m ]zw¡ t c3g�h w�rZq�\ m ] g \"] m;� ¢ _ l rV\ j ]ZrV� mBl ] c �&\�] g¶c x mBl ] gic [ mBh \ j�m rn}"ts]z� � � � m ] _ l \ h _ rVt¾}"[ j � �NrV�rnts� c }"tsr � ]zwZx cVg _ rV["� h \ j;c \"] c x � �#q � � ´ r e­� ] m � cVgi� � gic [ m ] g �N\ cVm5mic w"] m ] _ mNmil ]#] gig�c \"] c ["�w"r m r � ¡ [ g�mil ] g��­cVg ]Vu mBl ] gic [ mBh \ j¯m rV}"ts]z� o d"gih \ m¾g ] _ ] h {3]zwF�N] g ]Nw�]?� hkj \�r m ]?w�rn� c3d�mihs� rVtvu�� l�h _ lj rT{V] mBl ] �/l"hsj3l ] g _ g ]?w h } h t hkm�eµmBl rn\ cnmBl ] g � h ��] � o c3� ] mil"h \ j t hs� ]Z�nX�u¦XVX3X gic [ mBh \ j rnw"w g ]z�i��]?�rntst d�c3h \ m ]?w mBc � ��q �

� $ J£ST>'Q�J�>'S %�E � <�HKJ � L E� � <��R> � º \ �T�4YV[�t e �T�V�f §u � ] m � c3g�� o c ts[ mBhsc \"��q�\ _ � r mim ] �Zd�m ]zwmic�g ["\ mil ]­rV[ mBcVj ]?\"] g r mihsc \ c x mBl ] mBcVd ��tk]z{3]zt w c3� r h \ �?c \"]Z±"ts]?�zu)� l�h _ l4g ]?��["t m ]?w x g�c3� mBl ]x r h ts[ g ] c x�r d"g�c3j3g r � _ c \'{V] g9mBh \ j q�\ j3g ]?�)w�r m r h \ mBc&mBl ]N¨ � o m rV}"ts]z�?u _ c3g�g [ d�mih \ j&mBl ] � _ c3� rn\"w� \"] m w c3� r h \"� h \ mBl ] mBc3d �¼ts]�{3]?t�w c3� r h \ \"r � ]#�i] g {3] g ~ ¨ � o � u � r h \ m r h \"]?w�} e � o§q ��� [�rnt hkm�e �rn�i�i[ g rV\ _ ]�rnt|r g�� �#�5] g ]­]�{ h w"]z\ m t e©hkj \ c3g ]?w�rV\"w mBl ] _ c3gig [ d�m ]?w²±�ts]z�¶�5] g ] g ]?tk]�rV��]?w r m ^§�¦WVX� � � � � ¨ � c \ �¸  YV["t e � � hÂmBl � h w"]?� d"g ]?rVw²]z»£] _ m � �;º#mBl ] g �i] g {3] g � _ cVd"h ]zw mBl ] _ c3gig [ d�m ]?w±"ts]?��x g�c3� mBl ] � o§q�{V] g � hsc \ ��aNc3gig ] _ m ]?w²±�tk]?���5] g ] h �i�i[�]?w�� l"c [ g �Dtsr m ] g u�rnt mBl�c [ j3l {nr g�hsc ["�d�gic }"tk] � �½t h \ j ] g ]?w �

� � E�J'�"@ % H =zST<"J 3> 3<�L L HKJ � � L E� � <��R> � º \��¸�;Y3rn\P["r g�e �T�3�VX�u mil ]#� � � � t c \ j �¼w h � m rV\ _ ]&\"] m �� c3g�� �i[�»£] g ]?wÃrD\�r mBhkc \f� h w"] _ c \ j ]z� mBhkc \ d"gic }�ts] � mil r m ]z»£] _ mBh {3]?t e � l [ m w c �&\­t c \ j ��w h � m rV\ _ ]_ rVtst h \ j x c3g#�­c3g ] mil rV\²� l�c [ g � � � l ] d"g�c }"ts] � �½rV� mig r _ ]?w mic r�³Rr�� h \ mil ] g ] _ c {3] g�e � c x m ��Nr g ] h \µ]�r _ l o hsj \�rVt h \ j o e � m ] �  Z�9� hkm _ l�mBl r m ]?\"rV}"ts]zwª]�r _ l \"] hkj3l } cVgih \ j �9� hkm _ l«mBc _ g rn� l� l ]?\ g ] _ ] h { h \ jÃmBg r _ x gicV� ry\"]z�&t e _ g rn� l ]zw4��� hÂm _ l�mBl r mDl rnw4r m�m ] �­d�m ]?w mBcµg ] h \ hÂmBh rnt h�� ]

� �

Page 41: Practical Architectures for Survivable Systems and Networks (Phase

hÂm ��]?tkx � � l"h � _ g rV� l d"l ]z\ c3� ]?\ c \ d"gicVd r j r m ]?w g ] d ]?r m ]zw"t e²mBl�gic [ jVl"c [ m¶mBl ]­]z\ mihsg ]­\"] m � cVgi� urn\"w g ]?��["t m ]?w h \µrVt �­c � m \ c t c \ j ��w h � m rV\ _ ] _ rVtkts� j ] mimih \ j�mBl�gic [ jVl1�

� A � A �¼Q¸< � >f@iQ¸>PL <�! E ��ST<��R> � º \0��W � d"g�h t;���3�3��u&� � � � � � d r _ � ] m ��w"r m r x g r � ]�� g ]zt|r e\�] m � c3gi� _ c tkt|r d �i]?w mBl"g�c [ j3l�c [ m�mil ]ª¬¯\ hkm ]?w�o m r m ]?� � � l"h �­\"] m � c3g��+h �Z["��]?wbx c3g }"["� h \"]?���_ ["� mic3� ] g �zu _ g ]?w hkm � _ r g wªr _ mBh { hÂmBh ]?�?uR}�rn\ �ÃmBg rn\"�Br _ mBhkc \"�?u mBg r�{3]?t g ]z�i] g {nr mBhkc \"�?u�r �Zc \ jZcVmBl ] g � �� l ] c [ m r j ] g ]z�i["t m ]?wÃx g�c3� r;x rn["t m�e � c x m �Nr g ]�[ d"j3g rnw"] c x r _ hsg _ [ hÂm _ r g w h \yr�� h \ j tk]#�9� hkm _ l urn\"wF]z»£] _ mBh {3]?t e _ g ]?r m ]zw�r�}"t|r _ � � l"c ts]���t hs� ] d r mBl;mil r m � l [ m w c �&\ mBl ]N]?\ mBhkg ]½\"] m � cVgi� u h \F� c3� ]_ rV�i]z�¯x cVg rV�It c \ j rn�¯^V� l�c [ g � �

��� >P=zST>'Q�JbO�E§C;>PQ�E ��ST<��R>P= � � tk] _ migih _ d�c �N] g�c [ m r j ]?� c \©^ZYV["t e ���3�3��rn»£] _ m ]?w©r m tk]�rV� m �TX¿ ]?� m ] g \©� m r m ]z� � � l ] c [ m r j ]��NrV� g ] d�c3g�m ]?w"t eÃmBg�hsj3j ] g ]zwª} e r�� h \ j ts] mBg ]z] h \«q�w�r l�c _ c3�Zh \ jh \ _ c \ m r _ m � hkmil r mig rV\"� �­h �i� hsc \ t h \"]Vu�rVt mBl"c [ j3l � rV\ e cVmBl ] g ]z{V]?\ m � _ c \"� d"hsg ]?w mBc _ g ]�r m ]mil ] � rV�i� h {V] d"gic3d r j r mihsc \ � ¡ [ g9mBl ] g�� ¢ m ]?\"� h {V] ¿ ]?� m­aNc rV� m�c [ m r j ]?� c \ ��Xª�#[ j [�� m �T�3�V�r�»�] _ m ]zw«� �Zh tkt hsc \ _ ["� mic3� ] g � h \µ��� m r m ]z�?u a rV\�rnw�r�uRrV\"w ´ r � rµ~ � ]�¢ h _ c'���

� � <�L®< � ! $�� =?<�ST>PL LKH ST> �¼<�H L��)Q¸> � � l ]�t c �i� c x mBl ] c3gih ]?\ m r mBhsc \ c x mBl ] (¯[ j3l ]z� (#o��3X�� � rnt|r�¢ eq � �ir m ]ztst hÂm ] c \��T� � r e �T�3�3�µ~ g ]?��["t mih \ j x gic3� r � rVtkx®[�\ _ mihsc \ c x¾} cVmilµmil ] d"gihk� r g9e � e � m ] �� ���mBl ]�}�r _ � [ d � e � m ] � � _ rV["��]?w©rV� � rn\ e rV�¯�fX �­h tst hkc \ d r j ] g � e � m ] � � mBc x r h t�r _ gic ��� mBl ]¬¯\ hkm ]?w�o m r m ]z�?uRrV�½�5]?tkt�rV� mBl ]�t c �i� c x � rV\ eÃcVmBl ] g �i] g { h _ ]?��rVts� c�d"gic { h w"]zwy} eÃmil r m �ir m ]ztst hÂm ]� r�»�] _ mBh \ j d£cVh \ m � c x|���irVts]�w"]z{ h _ ]?�zu l"c � d�hkm rnt c3d ] g r mBhsc \"�?u#rV\"w cVmBl ] g r _ mih { hkmih ]z� � q mÃmBcPc3���]z{V] g rnt½w�r e � mBcªg ] _ c \�± j [ g ] mBl ] _ c3�Z� ["\ h _ r mihsc \��?u¾[�� h \ jªcVmBl ] g �ir m ]ztst hÂm ]�x r _ h t hÂmBh ]?� � ~ � � ccnmBl ] g x r h ts[ g ]?� c x (¯[ j3l ]z��(#o��3X��D�Br m ]?tkt hkm ]?� c _?_ [ gig ]?w � � rVtsr�¢ e � qiq c \����­YV["\"]Z�T�3�V�Zrn\"wrn\ cVmBl ] gFc \ ��YV[�t e ���3�3�ªrn»£] _ mBh \ j W �   �­h tst hkc \²¨ hsg ] _ � � �i["}"� _ g�h }�] g � � }"[ m�mBl ]Ã}�r _ � [ d� e � m ] � �&� c3gi� ]?w d�gic3d ] g t e h \y} cVmilyc x mil"c ��] _ rV�i]z� �¦�

� ��<�JªG�Q¸<�J'fHK= 3E � <�! Q¸>P<�O�EPCF>'Q#E���ST<��R> � � m ���Â�¸� � � � � c \ mBl ] �Zc3g \ h \ jIc x"��¨�] _ ] � }£] g���3�3��unr d�c �N] g �i[ g�j ] g ]?��["t m ]?w;x g�c3� rV\Fr mim ] �­d§m mic�g ] _ c \"\�] _ m r d�c �5] g � m r mBhkc \ mic�mBl ] j3g�h w �}�[ m � hkmil"c [ m ± g � mIl r�{ h \ j�g ] �Zc {3]?wyr m ] �Zd£cVg r g9e­jVgic ["\�w _ c \"\�] _ mihsc \ � � c3g ] mBl rV\yr �­h tst hkc \d ] cVd ts]��5] g ] rn»�] _ m ]?w1u � c3� ] c xN� l"c3� �N] g ]�� hÂmBl"c [ mDd£c �5] g x c3g rV��t c \ j rV�;� l"c [ g � � o§rV\¡ g rV\ _ h � _ c � hsg�d£c3g9m �½rn� _ t c �i]zwZx cVg � � � l"c [ g � � � l ] � r _ h ± _ o mic _ ��� ¢ _ l rV\ j ]Vu�p�r d�h w � g rV\"� hkm u� �¯� �?u c _ ]z�?u)rV\"w l�c � d"hÂm rVtk���5] g ]�� hÂmBl"c [ m�d�c �5] gz� � r gihsc ["���i] _ c \�w�r g�e ]z»£] _ m �Dr gic �i] � x cVg]�¢�r �­d ts]Vu mBl ]­�i[ g�j ] _ rV["�i]zw o�p&q c \"t e r �Zc3� ]?\ m r g�e }"t hsd u)}"[ m�mBl r m �½rn�F]?\ c [ j3l mBcµm r � ]� rV\ e _ c3�Zd [ m ] g �&w c �&\�x cVgIl"c [ g � � ~vo§]z]Dp¯q9o�°Do£u"{ c t � ^nX�u"\ c � � �3�DrV\"w��¸^ �¦�

��� <�J)=?<�=��FH S !0O�E§C;>'Q E���ST<��R>+STQ�H ���R>'Q�=ªJ�<�S¸H®E£J�<�LD<�H Q�@�STQ¸<�� =�J�<"Q�L � � m;mil ]ð¶rV\"�irV�aNhÂm�e ~ º tsr mBl ] � � hsg p c [ m ] � g r _ aNc \ mBgic t a ]?\ m ] g u½r m ���ÁX3W � � � � a o � c \��T�²¨�] _ ] � }£] g���3�f §uPr m ] _ l \ h _ h rV\ g�c [ m ]?w d�c �N] g5mBl�gic [ jVl l rVtÂx c x mil ] g ]?w"[�\"w�rV\ m ��[�\ h \ m ] gig [ d�mBh }"ts] ��d�c �N] g� e � m ] � u d"g ] d r g r mBcVg�e�mBc²d ] g x c3g��­h \ j rn\"\'[�rVt d"g ]z{V]?\ mBh {3] � r h \ m ]?\"rV\ _ ] c \ mBl ] cVmil ] g�l rVtkx �¬¯\�x c3g9m ["\�r m ]?t e u l ]yr d"d r g ]?\ m t e4d [�tsts]zw mBl ] � g�c \ j _ hsg _ [ hkm } c r g w1u�rV\�w mBcPc3� w c �&\ mil ] g ]��� r h \ h \ j�l rVtkx1rV�5�5]?tkt � � l ] � r h \ m ]z\�rV\ _ ] d"g�c _ ]?w"[ g ]�rnts� c } ePd rV�i��]?w mBl ]#� m rV\"w"} eZj ]z\"] g r mBc3g �rn\"w ] � ] gij ]?\ _ e }�r m�m ] g�h ]z� � � l ] g ]?�i[�t mBh \ j©c [ m r j ] mic§c3��c [ m�g rVw hkc _ c3�Z� ["\ h _ r mihsc \���� hkmilr hsg _ g rnx m u g rVw�r g�h \�x c3g�� r mBhsc \1u¾rn\"w d"l"c \�] t h \"]?� mBcªcVmil ] g _ c \ mBg�c t _ ]?\ m ] g � � � c �5] g �NrV� c [ mx cVgNc \"t e � �­h \'[ m ]z�?u _ c3�Z� ["\ h _ r mihsc \"� �5] g ] g ]?� mBc3g ]?wy� l"cVg�m t e­mil ] g ]�rnx m ] g u"rV\"wÃ}"r _ � [ dyg rVw�r g�NrV��� c3gi�'h \ j } e �§�À^VX � � � � ( c �5]z{V] g u¾r m ts]?rV� m WVX3X d t|rn\"]?���5] g ] h \ mil ] º t|r mil ]�� _ c \ migic tkts]?wr hsg � d r _ ]«r mZmBl ] mihs� ]Vu½rn\"w mBl ]�]�»�] _ m � d"h tk]?w [ d \�r mihsc \f� h w"] � (¯["\"w g ]?w"� c x#³ hkj3lfm �­�5] g ]

��`

Page 42: Practical Architectures for Survivable Systems and Networks (Phase

_ rV\ _ ]?ts]zw1uRw h {V] g9m ]?w�u c3g w"]zt|r e ]zw � � rV\ e w"]zt|r e �¯�5] g ]FrV�¯t c \ j rn��^ l"c [ g �?uR� hkmil � c3� ]¶w"]zt|r e �_ c \ mBh \P[ h \ j�h \ mic�mBl ]¶]z{V]?\ h \ j"�

� l ] g ] � r h \ h \ j _ rn�i]?��\ cVm ]zw l ] g ]Ãr g ]�]�¢�r �Zd tk]?� c x cVmBl ] g�m�ePd ]?� c x&r _?_ h w"]?\ m rVtN��[ g { h {nrV} h t hÂm�ed"g�c }"ts] � �zu�rVt mBl"c [ j3l ts]z�i�I� h w"]z� d"g ]�rVw h \ mBl ] hsgIg ]?��["t mih \ j ]�»�] _ m � �

� µ<���!�E�J�@ ��ER<"Q % O Q¸E �¾L®>�� = � � � c � h _ c \"w"] g�c3j r�� _ tsrV�i� _ g [ h �i] g �Z~ mBl ]�¬#o"o�(�["] aNhÂm�e rn\"w¬#o"o ��h _ � ��}"[ g�j'� �N] g ] d [ m¶c [ mDc x _ c3�­�Zh ��� hkc \ª}�] _ rn["�i] c x5w h _ [�t mBh ]?� h \ h \ m ] j3g r mBh \ j \"]z�c \§��} c r g wb�N]?r d£c \§� _ c \ mBgic t�� e � m ] � � c x m �Nr g ]Vu h \'{ c tk{ h \ j � �­h tst hkc \ t h \�]?� c x _ c w"]�~Kp&q9o�°Do{ c t � �T��uP\ c"� �V� ��� � l ] � r�{ e � � ¿�h \"w c �&� � � }�rn�i]?wÃo � r g�m o l"hkdZm ] _ l \ c t c3jVeZh �5rnts� c _ rn["� h \ jd�cVm ]?\ mBh rVtst e ��] gihkc ["�)w h _ ["t mih ]?� � ¡ c3g ]�¢"r �­d tk]Vu h \;o§] d§m ] � }£] g �T�3�3 §u mBl ]��#] j3h � �­h �i� h ts] _ g [ h �i] g¬#o"o � c3gi�fmBc �&\D�i[�»£] g ]?w;r&� e � m ] � ��x r h ts[ g ] w"[ g�h \ j&� rV\"]?[§{3] g � c » mBl ] _ c rV� m�c x a r d ] aNl r g tk]?�?u�#hsg�j3h \ h r�uRrV� mBl ] g ]?��["t m�c x�rV\ª["\ _ l ] _ � ]zw4w h { h w"]���} e � � ] gic h \©rV\ � � r d"d t h _ r mBhsc \ � � l ]F� l"hkd�NrV�Dw"]�rnw h \ mBl ]Z�Nr m ] g x cVg ^ l"c [ g ��rV\"w��'� �Zh \'[ m ]?� � �#\�]�r g t h ] g t c �i� c x d"g�c3d ["tk� hkc \�rVts� cc _?_ [ gig ]?w c \�^ � r e �T�3�f y~Kp&q9o�°Do�{ c t � �T��u�\ c�� �3� ���

� A5E � <�:)<fC � � H =�=�H L >²<���ERQTS � º \ ^ �#[ j ["� m ���3�3��u�r � c3� r l r�� �«�Zh ��� h tk]���["w"w"]z\"t eª� rVw�]rµ� c x m t|rV\�w h \ j�h \ mBl ] �Zh w�w"ts] c x¯rV\ r d"d r g ]?\ m t e �i[ _z_ ]?����x®["tItsrV["\ _ l�� � l ]Ãrn} c3g9m ��]� '["]z\ _ ]�NrV�Nr _?_ h w"]z\ m rVtst e�mBg�hsj3j ] g ]zw�rV�Nr g ]z�i["t mNc x�r;} hÂm w gic3d"d ]?w�} eZmBl ] l r g w��Nr g ]nu d�c �i� h }"t e w"["] mic� mBg r e ]?tk] _ mBgicV� r j \"] mih _ g rVw h r mihsc \«~Kr _ c � �Zh _ g r eZl"hkmNc3gNcnmBl ] g x c3g�� c x h \ m ] g x®] g ]?\ _ ] � �Fc \ mBl ]_ c3�Zd [ m ] g?��� ~ º \©� ¨�] _ ] � }�] g �T�3�3��u�rV\ª]?r g t h ] g � c3� r l r�� � _ g [ h �i] �Zh ��� h tk] _ g rV� l ]?w²w"[ gih \ jtsrV["\ _ l }�] _ rV["�i] hkm � �­h w _ c [ g ��] d"gic3jVg r ��l rVwy}£]z]?\ªr _?_ h w"]?\ m rVtst e ] g rV��]?w c \µt c rVw h \ j"�¦�

� � L®< � � <fC � :)>PL H 3ERO�ST>'Q 3Q¸<�=?:)>P= � q�\ m ]?� m �?u g rVw hsc �½r�{V]?� mBg�hsj3j ] g ]zw r _ cV�­d tk] m ] lfe �w g rV["t h _ x r h tk[ g ] c x5rì�(I��3X ´ t|r _ �'l r�� �ªl ]zt h _ c3d�m ] g u�]z»£] _ mBh {3]?t eªj ]z\"] g r mBh \ j x rVtk�i]F]zts] _ mBg�c \ h __ c3�Z� rV\�w"� � � �5]?\ m�e � m � c d ] c3d tk]��N] g ] �'h tstk]?w h \y±�{3] ´ t|r _ � (#r�� � _ g rV� l ]z��}�]zx cVg ]¶� l"h ]?tkw h \ j�NrV��rVw"w"]zw micµmil ]�]?ts] _ migic \ h _�_ c \ mBg�c ts� � ¡ r h ts[ g ]?� h \ cVmil ] g � e � m ] � � l r�{3] rnts� c }�]?]z\4t h \ � ]zwmic ]?ts] _ migic3� r j \"] mBh _ h \ m ] g x®] g ]?\ _ ]�rn\"w g�cVmBcVg _ c \ mBg�c t x r h ts[ g ]?� � ~ º \��TWµ¨�] _ ] � }�] g �T�V�3��u����� � � � � ���Ng ] d£c3g9m ]zw mil r m¯g ] d ]?r m ]zw�\ cnmBh _ ]?� c x)x r h tk[ g ]z� l rVwµ\ cVm }�]?]z\ªr _ m ]zw�[ d�c \ �¦�

� �FS¸:)>'Q&>PL >�VSTQ¸E��4<���J�>fS¸H �HKJ�ST>'Q �v>PQ¸>PJ'3>D<� > VSTHKJ � %)>�¼>PJ)=?>F= !�=zST>�� = � � r mBgihkcVm w"]�x®]?\"��]?�rn\"w � g ]?w"r mBc3g [�\ � rn\"\"]?wyrn] gih rVt£{V] l"h _ tk]?� g ] d£cVg�m ]zw"t e _ rn\"\ cVm � c3g�� d"gicVd ] g t eZh \ _ ] g9m r h \ x c3g �] hsj \ _ c [�\ migih ]?�y~ � ] gi� rV\ e u�Y3r d rV\1u o c [ mBl ° c3g ]�r�u¾rV\"w ´ r l"g r h \ r g ] d r g�mBh _ ["tsr g¶h \"� m rV\ _ ]?� �}�] _ rV["��] c x�x g ]� '["]z\ _ e _ t|rV� l ]?� � ¡ c3g ]�¢�r �Zd tk]Vu � r mBgihkcVm��Zh ��� h tk];� e � m ] � g rVw hsc �zu g rVw�r g �?u�rn\"ww"r m r��¼t h \ �Zm ] g��­h \�rVts� _ t|rn� l � hÂmBl ° c3g ]?rV\ _ ]?tkts["tsr g½d"l"c \"]?� �£d r j ] g � c x¾¬ � o � x c3g _ ]?� _ tsrV� l � hkmilY3r d rV\"]z�i]yrV] gic \�rn[ mBh _ rVt�� e � m ] � � � _ gih } �­c \ hkmBcVg �D["�i]zw c \ ¬ � o � }�rV��]?� _ t|rV� l � hkmBl � ] g�� rn\m ]?tk] d"l"c \"]��i] g { h _ ] � q�\ ´ r l�g r h \1u�o � o'�¼�fXyrV\"w o � o'���3� g rVw�r g �¶r g ]�["\'["�BrV}�ts]�}£] _ rV[��i] c x h \§�m ] g x®] g ]z\ _ ]�x g�c3� mil ]¶\�r mBhkc \�rVt m ]zts] _ c3�Z� ["\ h _ r mihsc \��N�i] g { h _ ]?� � ~Ko§]?] mBl ] ��� � ��� � � � ��� �#h �i��["]g ]?tk]�rV��]?w«^V� º _ mBc }�] g ���3�3� �¦�

� 8�:�E���E�=FO)Q¸E���>«L E�=�=z>§= � � l ] � l"c } c �Iq d�gic }�]��½rn�¯w c§c3� ]?wÃ} e r�x rn["t m�e � c x m �Nr g ]D[ d w�r m ]Vu� l�h _ l _ rV["�i]zwµr;t c ��� c x�� c t|r g5c3g�h ]z\ m r mBhkc \1uf� l"h _ lÃh \ m [ g \ g ]?��["t m ]?w h \ w h � _ l r g�j ] c x mil ]�� c t|r g}"r mim ] gih ]?� � � l�c } c �¯q�q5]z\ _ c ["\ m ] g ]?w©r�� hs�Zh t|r g x r m ]�� l ]?\ mBl ]DrV[ mBc3� r mBh _ rV\ m ]z\"\�r g ] c3gih ]?\ m r��mihsc \�x r h tk]?w1u _ rV[�� h \ j r d ] gi� rV\"]?\ m t c �i� c x _ c3�Z� ["\ h _ r mihsc \�� � o§]�{3] g rVt�� hs�Zh t|r g _ r m rn� mBg�c3d"l ]z�r g ]�t h \ � ]zw mBc x rV["t m�e�� r h \ m ]z\�rV\ _ ] �

_!�?� %�352?&��$,56 ���?+B&X358Y,)*�!+B&"&*�*+B'B'N21/1;�/1,� !/G�*,�-��#3&(6 IL,2G;�/1,� �*�1� )���&�2?' ��&!,56 ���?�$O1/:35' 35/:35' I�&�+B&QK��� �������X'B�W�!-��9;�/?,� $#

� �

Page 43: Practical Architectures for Survivable Systems and Networks (Phase

� �FS¸:)>'Qy=?O)< 3> 3<�=?>P= � º#mBl ] g _ rV�i]z� c x�\ c \"�i[ g { h {nrV}"tk]�� e � m ] � ��r g ];rVts� c � c3g�mil \ cVmih \ j ��~9� �mil ] _ c � �Zh _ g r e } c3� }�r g w � ]z\ m�c x � ¨�p�o h \ �T�3�V�²~ � l"h _ l _ [ m�mil ] aNl rntsts]z\ j ] g�� � _ cV�­� [�\ h �_ r mBhkc \"� h \ l rVtkx � u�~K^ �NmBl ] h tstÂ�vx r m ]zw aNl rVtkts]z\ j ] g tsrV["\ _ lµh \²�T�V�3��w"["] mBc rV\ º � gih \ j �N]?r � ��t h \ �d�gic }"tk] � u1~ W � ��["\"� d£cVm r _ mBh { hkm�e�mBl r m rn»£] _ m ]?w mBl ] _ c3�Zd [ m ] g �&rV\"wyrVt m ] g ]?wyo �'e tsrV} � � c3g } hÂm½h \���f V��u�rV\"w4~ � � rV\µ� m tsrV�9� a ]?\ m rn[ g � l"c ��] d"g�c3j3g r � �NrV��rVt m ] g ]zwy} e t hsj3lfm \ h \ j��

� 8#<�STQ�H E�S�� HK=?=�HKL®> %�>�¼>PJ =?> � q�\brVw�w hkmihsc \1u � rn\ e _ rV�i]z� l r�{3] c _z_ [ g�g ]?w h \�� l�h _ l � e � m ] �x®[�\ _ mihsc \�rnt hkm�e _ c \ mBh \P[�]?w²}"[ m�mil ] c {3] g rVtkt d ] g x c3g�� rn\ _ ];�NrV��\ c t c \ j ] g _ c \"� h � m ]?\ m � hkmBl ]�¢'�d ] _ m r mihsc \�� � ��\+]�¢"r �­d tk] h � d"gic { h w�]?wb} e mBl ] � r mBg�hscVm � c x m �½r g ]�� l"c �i] _ t c _ � w g�h x m ]zw x r g]z\ c [ jVl mBc�d"g ]z{3]z\ m�hÂm x gicV� rVw�]� '[�r m ]?t e­mBg r _ �'h \ jFmil ] h \ _ c3�Zh \ j o a ¬#¨ �Zh �i� h tk] mil r mIl"hÂm½mBl ]¨ l r l"g rn\�}�r g�g r _ � � � q m½�Zhsj3lfm }£]��Br h w mil r m�mBl ] _ c3�Zd [ m ] gNl r g w��Nr g ]��i[ g { h {3]zw�~ hÂm _ c \ mBh \P[�]?wmic w c�hÂm � _ c3�­d [ m r mihsc \�� � un}"[ m mil ]I\"] _ ]?���Br g9e r d"d t h _ r mBhkc \�x®[�\ _ mihsc \�rnt hkm�e w h w�\ cVm �i[ g { h {3] c {3] gmil ] �TXVX l"c [ g � mBl r m#mil ]�� e � m ] � l rVw©}�]?]?\ g ["\"\ h \ j ~ h \"� m ]�rVw c x mBl ] �?� l"c [ g ��� d ] _ h ±�]zw²} emil ] g ]� '[ hsg ] � ]?\ m � ��� � l�h � h tkts["� mBg r m ]z� mBl ] x r _ mFmil r m �5] � ["� m rVtk�Nr e ��w�]z±�\"]y��[ g { h {nrV} h t hÂm�e� hÂmBlÃg ]?� d ] _ m&mBc � d ] _ h ± _ g ]� '[ hsg ] � ]?\ m � c3g ]�¢ d ] _ m r mBhkc \"� c x mBl ]Dr d�d t h _ r mihsc \1u'\ cnm � ["� m&c x mBl ]� e � m ] � � c x m �Nr g ] �

� ��<�� L®> ���ST= � q�\;\P[ � ] gic ["� _ rV��]?�zu'r�� h \ j tk] _ rV}"ts] �NrV� _ [ m un� hÂmBl r � r �zh \ j t e w h � d ] g �i]zw�]z»£] _ m �� h \ c \"] _ rV�i] g ]z�i["t mBh \ j�h \ d"gic t c \ j ]zw�w�]?t|r e ��r m rVtst mil"g ]z];r hsgid�c3g9m � h \ mBl ] � ]z� � c3g��µaNhkm�er g ]�r � � l ] g ] l r�{V] rVtk� c }£]z]?\ _ rV�i]z� h \�� l"h _ l � ["t mBhkd ts] _ hsg _ [ hÂm � l r�{3]­}£]z]?\ ��]z{3] g ]zw � hs� ["tÂ�m rV\"] c ["�it e3� q�\��T�V�3��u mil ]�]?\ mBhkg ] �¯c3g�mil ]�rV� mDc x mBl ]Z¬�\ hkm ]zw�o m r m ]?���NrV�¶�i] d r g r m ]?w²x gicV� mBl ]g ]?� mIc x mBl ]���p � ��\"] m }�] _ rV["��]¶rVtst��i]�{3]?\ _ hkg _ [ hkm �½r _ m [�rVtkt e �5]?\ mImBl�gic [ jVl mBl ]��ir � ] _ c \"w"[ hÂmh \ ¿�l"hÂm ] � t|r h \"� � q�\ �T�3���Vu m � c ±�}�] g � c3d§mBh _ t h \�]?� h \ª�#\"\"rV\"w�rVtk]Vu �#hsgijVh \ h r�u mil r m�l rVw²}£]z]?\h \ m ]?\ mihsc \�rntst e�d t|r _ ]?w h \µ�i] d r g r m ] _ c \"w"[ hkm � mBc rT{ c3h w��i[ _ l � h \ j ts]¶�N]?r � t h \ � �¯�5] g ];� hk� ["t m r��\�] c ["��t e �i]z{V] g ]?w1u rn»£] _ mih \ j �VX�u¦XVX3X m ]zts] d"l"c \"] _ hsg _ [ hÂm ��~ h \ _ ts["w h \ j�mil ] � ]z\ m r j3c \ rV\"w²\"]��&���] g { h _ ]z� ��� q�\ mBl ]�t|rV� m �5]?] �«c x5YV["\�]�^VX3X3X§u£w"[ gih \ j _ c \"� mig [ _ mBhsc \ d"g ] d r gih \ j x cVg _ c \"\"] _ mBh \ jmil ] ´ r e � g ]�rDp�r d�h w � g rV\"� hÂm ~ ´ �#p � � mBc¶mBl ]�o�rV\ ¡ g rV\ _ h � _ c � hkgid�c3g�m u'rDw g�c3d tk] m�c x��5]?tkw h \ j� r m ] gih rVt h \ r � rn\ l"c tk] � ["� m � c [ mBlÃc x o§rV\ ¡ g rV\ _ h � _ c _ rV["��]?wµr�± g ] mBl r m w"]z� mBg�cTe ]?w d�c3g�mihsc \"�c x ^3  _ rV}�ts]?�zu�� hsd�h \ jFc [ m½m ]zts] d"l"c \"]#�i] g { h _ ] mic ^3�§uÁX3X3X _ ["� mic3� ] g � �"mBl ] d"gic _ ]z�i� c x g ] d t|r _ h \ j�VX3X�x®]?] m&c x _ rV}�ts]�rV\�w _ c3gig ] _ m t e�g ] _ c \"\�] _ mih \ j�mil ] � rn\ eZmBl�c ["�Brn\"w"� c x�� hsg ]?�½�NrV�I]�¢ d ] _ m ]?wmic�m r � ]�r m ts]�rn� m&m � c �5]?] � � �

� ]�¢ m u"�5] _ c \"� h w"] g rFx®]z� _ rV��]?��r mimigih }"[ m ]zw mBc�� rnt h _ hsc [��½r _ m � �� �Ã>PJ)H <�L|@iE�� @ =?>'Q"��H�3>­<§S�ST< � =¶E£J $ ��8;=¶<�J'% =?>'Q"�£>'Q�= � � l ] � � � q � q9o � �i[�»£] g ]?wÃr¶�i]�{3] g ]w�]?\ h rVt c x �i] g { h _ ] g ]?��["t mih \ j x gicV� r = !�J � E1E&%)HKJ � r m�m r _ � ~ p¯q9o§°�of� �T� � �'�§ulfm�mBd �¦¥3¥ _ r m tk]?�i� � \ _ t � r _ � [ � ¥Vp h � � � ¥§�T� � �'� �ÁlfmB� t ���¾¿ ]?} aNc3� w h wµrVts� c ~Kp&q9o�°Do'� �T� � �3�§ulfm�mBd �¦¥3¥ _ r m tk]?�i� � \ _ t � r _ � [ � ¥Vp h � � � ¥§�T� � �3� �ÁlfmB� t ��� o§[ _ l ³ cPc w h \ j rV\"w g ]z� c [ g _ ]���]�¢ l rV["� mihsc \4r m �m r _ � �¯r g ] g ]zt|r mih {V]?t e ]�rn� eÃmBc�d ] g�d ] mBg r m ]Vu�}�] _ rV["��] mil ] e w c \ cnm�g ]� '[ hkg ]DrV\ e rV[ mil ]?\ mih _ r mBhsc \� hÂmBl"h \ mBl ]Dr m�m r _ � ]?w�� e � m ] � � �

� �yH =zSTQ�H � ��ST>�% %)>PJ)H <�L =�E � =?>'Q"��H 3> � ¿�hkmil"h \�r mBl�g ]?]���w�r e�d ] g�hsc w h \ ¡ ]?} g [�r g9e ^VX3X3X§ufr mim r _ � ��5] g ] m r g�j ] m ]?w r m¶� rn\ e � hÂm ]?� � h \ _ tk["w h \ j � r l"cPc u�� � r �zc \1u�] ´ r e u a½����� _ c3� u ´ [ eV� _ c3� u�1¨ � ] m u ��� � g rVw"]nu§rn\"w � ¢ _ hkm ] � _ c3�µ� � l ]?��]¯r mim r _ � � �5] g ]�tsrV["\ _ l ]?w�x gic3� h \ m ] gi� ]?w h r g�e � hÂm ]z�~ �?c3� } h ]z� �¯mil r m¶l rVw²}�]?]z\ _ c3�­d�gic3�Zh ��]?w©]�¢ m ] g \"rVtst e u1� l"h _ l�� rVw"] hÂm w h� _ ["t m#mBcÃmBg r _ �«mBl ]d ] g�d ] mBg r mBc3g � � ~Ko§]?]�p¯q9o§°�of�9^VX �  V��ulfm�mBd �¦¥3¥ _ r m tk]?�i� � \ _ t � r _ � [ � ¥Vp h � � � ¥3^VX �  V� �ÁlfmB� t �¦�

� �

Page 44: Practical Architectures for Survivable Systems and Networks (Phase

� 8#>PQ�=?E�J�<�L�3E��4O ��ST>'Q ��H®Q � =Ã<�S?ST< � = � ~vo§]z]Zo§] _ mBhsc \4^ � � � ^­x c3g }"r _ �'j3gic [�\"w c \ d ] g � c \�rVtÂ�_ c3�Zd [ m ] g { hsg [��i]?� �À� q�\ mil ] d ] g � c \�rVt _ cV�­d [ m ] g � c3g tkw c x � h _ g�c � c x m � c x m �Nr g ]nu mil ] g ] h �¶rV\]�¢ mBg r c3g w h \�r g�h t e t|r gij ]�\'[ � }�] gDc xI["��] g � d"g�c3d r j r m ]?w � g�c�� rV\ l"c3g ��]?�zu ["�i["rVtst e©g ]�x®] gig ]?w mBc rn�{ hkg ["��]?�?u�rV\"w l ] g ] h \ g ]�x®] g�g ]?w mBc rV� � a { hsg [��i]?�µ]z{V]?\ mBl"c [ j3l mil ] e r g ] m ] _ l \ h _ rVtst e \ cnm{ hkg ["��]?�#~ }�] _ rn["�i] mil ] hkg d"gic3d r j r mihsc \ g ]� '[ hsg ]?� l [ � rV\�r _ mihsc \"� ��� o c3� ] c x mBl ]z�i]�{ hkg ["��]?� l rT{V]g ]?��["t m ]?w h \;�i] gihkc ["� _ c \"��]� '["]?\ _ ]?� ��[ _ l rV�¾w h �Brn}"t h \ j � e � m ] � � � º x d r g9mBh _ ["t|r g \ cVm ]�� c3g9mBl"h \"]?���r g ] mBl ] ¿4c3g w � r _ g�c � h \ mil ] � ]?t h �i�ir«r m�m r _ � �Ã~ p¯q9o§°�of�9^VX � ^V��u¦^V����WV�"uÁW3��u·�fX�u·�3�"u·�'� � rn\"w mBl ]� _ g�hsd�mih \ j r m�m r _ l�� ]z\ m � h \ mBl ]�q� º ��� � º ¬*{ hkg ["�Z~®� � r e ^nX3X3X�u�p&q9o�°Do'�9^nX � �V�ÃrV\"w�t|r m ] g �rn\"w hÂm � _ cVd'e _ r m � d"h \ c »��zu�} cVmil�c x¾� l"h _ l ]�¢ d t cVhkm ]zwµx®[�\"w�r � ]?\ m rnt1�N]?r � \"]?���i]?� h \ � h _ g�c � c x mº [ m t cPc3� � c x m �½r g ] g ]?t|r mBh \ jZmic­mBl ];]�¢§] _ [ m rV}"ts];\�r m [ g ] c x r mim r _ l"� ]?\ m � � ~ � l ];q� º ��� � º ¬{ hkg ["�¯r _ m [�rVtkt e�h \�x®] _ m ]zw�� c3� ] _ t|rV��� h ±�]?wµ� e � m ] � ��rV\�w�\"] m � cVgi� �?uR� l"h _ l�c x _ c [ g �i] h �I� hk�­d t e\ cVm �i[ d"d�c ��]?w mic�l r d"d ]?\1u rVt mil"c [ jVl �5] � \ c � mil r mDc3d ] g r mBhkc \�rVtkt eymBl ] _ c3�­d ts] m ] h � c t|r mihsc \c x _ t|rV��� h ±"]?wy� e � m ] � � h �&r ��ePmil1�¦�

� �)=zSTQ¸<�L H®<�Jy=?<���E�ST<��R> � � � rV��� h {V] _ c3�Z� ["\ h _ r mihsc \���}"tsr _ �Vc [ m�h \�o e w"\"] e uV��["� mig rVt h r�u c \�^3^�¯c {3] � }£] g ���3�f N�½rn� _ rV["�i]zw;} e r � \ c �&ts]?w j ]�rV}�ts] �BrV} cVm ]?[ g � l"c�l rVwD}£]z]?\�r&x c3g�� ] g � ]?ts] _ c3�] �­d t cTe ]z] � � l ]&r mim r _ � ] g ��]z{V] g ]zw ^�� � r h \ _ rV}"ts]z� h \Ã��X#w h »£] g ]?\ m t c _ r mBhsc \"�?u¸� l"h _ l�l rnw�}£]z]?\_ r g ]�x®["tst e ��]?tk] _ m ]?w mBcÃl r�{V] � r�¢ hs� [ � ]�»�] _ m?� � l"h �¶r m�m r _ �«� \ c _ � ]?w c [ m Wf�§uÁX3X3X m ]?ts] d"l"c \�]t h \"]z�?u½� l [ mimih \ j w c �&\ � rV\ e _ c3�Zd [ m ] g �zu&}�rV\ � �?u m ]zts] d"l"c \"] c _ ]?�zu�� �¯� �?u d£cVh \ m � c x|���irVts]� e � m ] � �zuR� mBcVg ]?�zu m ]?tk]�¢§]?�zu�x r _ � hs�Zh ts]nu�rn\"w�}�] m�mBh \ j � c _ ]��i] g { h _ ]?� �N´ ] _ rV["��]FrVtkt h \ m ] g \"r mBhkc \�rVt��] g { h _ ]z��r g ] gic [ m ]?w mBl"g�c [ j3l o e w"\"] e u mBl ]­]z»£] _ m �;�5] g ]�\ cVm � ["� m t c _ rVt � q m �NrV�F�i[�� d ] _ m ]?wmil r m�mil ]Zr mim r _ �«l rVw²}£]z]?\�}�rV�i]zw c \ ^¸� e ]�r g � c tkw h \�x c3g�� r mBhsc \1u£}�] _ rV["��] mil ]��Br � ]�r m�m r _ � ^e ]�r g �&]�r g t h ] g � c ["tsw l r�{3]D}�]?]?\ _ cV�­d tk] m ]?t e w"]z{nrV� m r mih \ j�� �

� ��<�J�G�Q�<"J fH = 3E � L <� � E���S«<�S�STQ�H � ��ST>�% STE�=?< ��ERS�<��R> � �¸^V��uÁX3X3X _ [�� mBcV� ] g � h \²\ c3g9mBl ] g \o§rV\ ¡ g rn\ _ h � _ c ]�¢ d ] gih ]?\ _ ]?w�r d£c �5] g¾c [ m r j ]�x c3g rV� t c \ j rV� W � � l"c [ g �¾}�] jVh \"\ h \ j r m �§�k�¸� � � � �c \µ^3� º _ mic }£] g �T�3�f PuP� l ]z\µ±�{3] mBg rV\"�9x c3gi� ] g �Ir m rF� h \ j tk] d�c �N] g � m r mihsc \�� mBcVd"d ]zwÃ� c3g��'h \ j"�� l ] ¡ ´ q _ c ["\ m ] g�m ] gig�c3gih � � ["\ hÂm�h \f{3]z� mBhkj r m ]?w�� l r m�hkm _ c \"� h w"] g ]?w mBc }£]&�Brn} cVm r j ]nu'� l ] g ]z} eWV� c x mil ];�f^Z��� hÂm _ l ]z��r m�c \"]��i["}"� m r mihsc \ªr d"d ]�r g ]?w mic�l r�{3];}£]z]?\ � rV\'[�rVtkt eÃc3d ]?\�]?w � ~vo§]z]p&q9o�°Do'�B�T� � �'^ �¦�

� � < � >�% � >� =?H®ST>P= � � rV\ e�cVgij rV\ h�� r mBhsc \"�¾\ c ��w"] d ]?\�w c \ mBl ] hsg ¿ ]z}­� hkm ]z� x c3g w h �i�i] �­h \�r��mihsc \ c x mihs� ]?t e rV\�w g ]?t h rV}"tk] h \§x c3gi� r mBhkc \ � ( c �5]z{3] g u��i] gihsc ["� gih � � �¯]�¢ h � m&c x¾w�r m rV}�rn�i]?�¯}�] h \ jrnt m ] g ]zw�} eyh \ mig ["w"] g � � � rV\ e _ rV��]?� c x d"g rV\ � ��rV\"w«\'[ h �BrV\ _ ]Fr _ m ��rVtk� c _ tk]�r g t e w"] �­c \"� mig r m ]l�c ��{P["ts\�] g rn}"ts]F� e � m ] � �Dr g ] mBc r mim r _ ��� o§[ _ l�h \ mBg ["� hkc \"� _ c \ mBh \P[�] mBcÃc _?_ [ g u�}�] _ rn["�i] mBl ]� e � m ] � � g ] � r h \�{P["tk\"] g rV}"tk] � (�] g ] r g ] ryx®]z� g ] _ ]z\ m _ rV��]?� � ��t mBl�c [ j3l�mBl ] e �5] g ] �Zc � m t eh \ m ]?\�w"]?w4rV� d"g rV\ � � g r mil ] g�mil rV\ � rVt h _ hkc ["�#r _ mih { hkmih ]?�zu hkm¶h � _ ts]�r g¶mil r mDd ]?\"] mBg r mBhsc \"�D�5] g ]h \f{ c tÂ{3]?w�uRrV\"w mBl ]¶w�r � r j ]?� _ c ["tsw l r�{V]�}�]?]z\ � [ _ l � c3g ��] � ]?� d ] _ h rVtkt e�h \ _ rn�i]?� h \ � l�h _ lmil ] g ]��5] g ]Ã\ c ± g ]��½rVtkts� h � c t|r mih \ jymBl ]z�i] ¿ ]?} � hÂm ]z�;x gic3� h \ m ] g \�rVtN� e � m ] � �zu c3g � l ] g ] mBl ]± g ]z�NrVtkts�½�5] g ] hs�Zd"g�c3d ] g t e _ c \�± j [ g ]zw �� a q�� ~Kp&q9o�°Do'� �T� � �f� �� YV["� mih _ ]�¨�] d r g9mB� ]?\ m ~Kp&q9o�°Do'� ��� � W3� �� ¡ ´ q#~Kp&q9o�°Do'�9^nX � �3W �

� �W�?358Y,5����21)A_ )�+B��> _ , *b'H35%<;�4X2?� E 21&���)�35'B+H3 � +B/���� ������� � � � ���:K �1� >V,QML�Q-�8Y�Q) �^_ � � KX��I�>1/1�WILK E 21&*�*)<35'B+H3?K"��# � K � /1> ��>1+ �*+B,/TK)����1)*+B/��*��>G+B/ E �-���������� ��� ��������� �����!���"���$#%�� � ��K?ML,'(# � � K?/1,1# � K BL35/�2:35)*I �^_ ��� K:�1��# � � ! � � #

� �

Page 45: Practical Architectures for Survivable Systems and Networks (Phase

� ¨�] d r g�mB� ]?\ m&c x q�\ m ] gihscVg ~ p¯q9o§°�of�9^VX � �fW �� � l"g ]z]�� gi�;e­¿ ]z}«� hkm ]z�D~Kp&q9o�°Do'� ��� � �VW �� � hkg ¡ cVg _ ]Z~ p¯q9o§°�of� �T� � �V� �� � ��o§� ~Kp&q9o�°Do'� �T� � �3� �� o d r _ ]�o m r mihsc \ d"g�c }"tk] � g ] d�c3g�mih \ j w�r m rV}�rn�i]­~Kp&q9o�°Do'�9^nX � �f ¸���f� �� � r mihsc \"rVt aNc tkts] j3h r m ]#� mil ts] mBh _ ���i� c _ h r mihsc \ ~Kp&q9o�°Do'�B�T� � �3� �� ¬ � o � q�\�x c3g�� r mBhsc \ � j ]z\ _ e ~ p¯q9o§°�of�9^VX � �T� �� � ] c3gij ] ¿ �R´ ["� l _ r �Zd r hkj \ � hkm ]nu d"l"cVmic�g ] d t|r _ ]?w4~Kp&q9o�°Do'�9^VX � �V� �� � rntsts[ dyº�gij rV\ h�� r mBhsc \�~Kp&q9o�°Do'�9^VX � �3W �� Y3r d rV\"]z�i] ��c {3] g \ � ]?\ m o _ h ]z\ _ ]�rn\"w � ] _ l \ c t c3jne � j ]?\ _ e u _ ]?\��i["��w"r m r�] g rV��]?w ~ p¯q9o§°�of�^nX �  V  �� oP�5]?w h � l«� ]�r mBd r _ � ] g � hÂm ]­~Kp&q9o�°Do'�B�T� � ��� �� oP�5]?w h � lª� r mBhkc \�rVt ´Nc r g w c x (¯]�rVt mBl rV\"w ¿ ]?tkx r g ]Z~Kp&q9o�°Do'�^VX � �f  �� � r mihsc \"rVt�( c _ � ] e ��]�r j [�]Dw�]?\ h rVt c x �i] g { h _ ]Vu£�¸��w"r e�c [ m r j ]Z~Kp&q9o�°Do'�^VX � �3� �

q�\�rVw�w hkmihsc \1u1rµ¬ � o �)� ]z\"] g rVt�� _z_ c ["\ mih \ j�º _ ]�� m ["w e ["\ _ c {3] g ]?w � c3� ] g r mil ] g ] j3g ] j3hsc [����] _ [ gihÂm�e {P["tk\"] g rV} h t hkmih ]z� h \ mil ] ¿ ]z}Ã� hkm ] c x mBl ] � \'{ hkgic \ � ]?\ m rVt � g�cVm ] _ mihsc \­� j ]z\ _ eV� ¿�l ]?\mil"g ]?r m ]z\"]?wZ� hkmil ]�¢ d�c �i[ g ] c x mBl�c �i]&{P["ts\"] g rV} h t hÂmBh ]?� } e rV\Z]?\f{ hsgic \ � ]z\ m rVtkt e ["\�� eP�­d r mBl ] mBh _aNc \ j3g ]z�i� � rV\�u mil ] � � � _ l"c �i] mic­g ] �Zc {3] hkm � ¿ ]?}ª� hkm ]¶x g�c3��mBl ] � ] m rVt mic3j ] mil ] g ~ p¯q9o§°�of�^nX �  V  ���� l ] g ]y�NrV�ZrVts� c r g ] d£cVg�m�h \ � ��� ��� ��� � � � � � � ��� � ��� � mil r m r�¨ c ¨ }"t cPc w m�e§d ]yw�r m rV}�rV��]l rVw }�]?]?\4�i["}f{3] g�m ]?w�rV\"w }"t c§c w m�ePd ]­w�r m r«rnt m ] g ]zw�~Kp&q9o�°Do'� ��� � �3  � � l�c �5]z{V] g u mil r m;g ] d�c3g9m�NrV����["}"�i]� '["]?\ m t e _ c3g�g ] _ m ]zw1��\ c �i[ _ l d ]z\"] mig r mihsc \ l rVw c _z_ [ g�g ]zw1u�rVt mil"c [ j3l r g ]?w m ]�r �l rVw h w"]z\ mih ±�]zw mil ] d£c �i� h } h t hkm�e�c x��i[ _ l rV\�r mim r _ � rV\"w _ c \ m ] �Zd tsr m ]zw hÂm � d�c �i� h }"tk]Ã]z»£] _ m �~ p¯q9o§°�of�9^VX � Xf^ ��� � l ]Dx rVtstsr _ hkc ["� g ] d�c3g�m r d"d r g ]z\ m t e w h w _ rV["��] mBl ] � ]z\ m r j3c \ mBcZg ] _ c \"� h w"] g� l r m&h \�x cVgi� r mBhkc \ h � d [ m¯c \ hkm � ¿ ]?}µ� hÂm ]z� �

� G�< � >�% >3@ �4<�H L � ��h {V]?\ mBl ]�]?rV�i]F� hÂmBl � l"h _ l ]�� � r h t _ rV\²}£]F� d£cPc x®]zw1u hkm#h ��\ cnm �i[ g�d"gih � h \ jmic ±"\"w�{nr g�hsc ["� _ rV�i]z� h \f{ c tk{ h \ jZd�l"c \ e \�r � ]?�?uR]�� � r h t�rnw"w g ]z�i��]?��rV\�w«q � rVw"w g ]?���i]z�?u�} c3j [��_ c \ m ]z\ m uPrV\"w�]z{V]?\ rnt m ] g ]zw m ]�¢ m�c \�ts] j3hkmihs� r m ] � ]?���Br j ]z� � rV���N]ztst�rn� g r �Zd rV\ m � d r � � x gic3�} c3j [��&rVw"w g ]?�i��]?�zu£� _ r � �?uRrV\�w cVmil ] g rn\"\ cTe rV\ _ ]?� �

� �FS¸:)>'Q �4<"LKH�fH E��)=�<§S�ST< � = � � rV\ e � e � m ] � c [ m r j ]z� l r�{V] g ]z�i["t m ]zw�x gicV� � rnt h _ hsc [���r m �m r _ � � � q�\ mil ]Z� c3g tsw c x _ c \f{V]?\ mBhkc \�rVt _ c3�Zd [ m ] g � e � m ] � �?u mil ] g ] l r�{V] }£]z]?\4{nr g�hsc [�� � rVt h �_ hsc [��#r m�m r _ � ��["� h \ j�d ]?\"] mBg r mBhkc \"��rn\"w � gic�� rn\ l"c3g �i]?�zu h \ _ tk["w h \ j r�{nr gih ] m�eµc x�t c3j3h _ } c3� }��rn\"w mihs� ]�} cV� }"� h \"��] g�m ]?wµ} e w h � jVg ["\ m tk]?wµ] �Zd t cTe ]?]?�zu�r m r �­d ] g ]?wµw�r m rn}�rV�i] mBl r m rn»�] _ m ]?w� ]?\�] g rnt ¨ e \�r �­h _ � � �¯� m t|rn� g�c _ � ] m ~ g ]?��["t mih \ jZh \ mBl ] _ c \'{ h _ mBhkc \ c x mBl ] d ] gid ] mig r mic3g � �i]z]p&q9o�°Do'�B�3� � �f� � u r«��[ gig ] d�mihkmBhkc ["��t e _ l rV\ j ]?w d rn�i��� c3g w mil r m ]z»£] _ mih {V]?t e }"t c _ � ]?w ["�ir j ] c x&r¿ rV� l"h \ jnmBc \1u§¨ a _ hÂm�e _ c3�­d [ m ] g � e � m ] � ~ h \ g ] m rnt h r mBhsc \Zx c3g rVtstk] j ]zw g ]?r _ mihsc \�� mBcFmil ]��Brn} c �m ]?[ g�� � _ g�hkmih _ h � � c x l"h ����[ d ] gihkc3g � � u rn\"w mil ]�r d"d r g ]?\ m t e²h \ m ]z\ mihsc \"rVt � rnt h _ hsc [���w"]?tk] mBhkc \ c xmil ]Frn\"\'[�rVt ±"\�rV\ _ h rVt g ] _ c3g w"�#x c3g r mBc �&\ h \«� gih��?c \"r � q�\ � rV\ e�cVmBl ] g _ rV�i]z�?u�r � e � m ] � �i[P�d ] g ± _ h rVtst e r d"d ]�r g ]?w mBc }£] cVd ] g r mih \ j _ c3gig ] _ m t e u�}"[ m&l rVwµr _ m [�rntst e }�]?]?\ m r �­d ] g ]?wÃ� hkmilµcVgd ]?\�] mBg r m ]zw h \y�i[ _ l r��Nr eÃmBl r m&� [ _ lµj3g ]?r m ] g w"r � r j ] _ c [�tsw l r�{3] c _z_ [ g�g ]zw �

p&]zx®] g ]?\ _ ]?� mBc�mil ]?��]�rn\"w � rV\ e�cVmBl ] g � hk�­h t|r g _ rn�i]?� c x)\ c \��i[ g { h {nrV}"ts]�� e � m ] � �¯rV\�wµ\�] m � c3gi� �

� �

Page 46: Practical Architectures for Survivable Systems and Networks (Phase

_ rn\Z}�]Ix c ["\"w h \ � ]?[ � rV\"\ � � � $ � � � } c§c3� ¹ ^V�VX Ä rn\"w h \ mBl ] c \P��t h \"]½r g _ l"h {3]?� c x mBl ]�p h � � � ¡ cVg [ �r m&lfmimid �¦¥3¥ _ r m ts]z�i� � \ _ t � r _ � [ � ¥Vp h � � �B¥§u"� l ] g ] e3c [ _ rV\y} g�c �&�i]�rV\"wy�i]?r g _ lymBl"g�c [ j3l p&q9o�°Do h �i��["]?� �� _ c3�Zd ]z\"w h [ � c x�� l�c3g�m u �Zc � m t e�c \�]���t h \"] g ufw"]z� _ gihsd§mBhsc \"� c x _ rV��]?�¶~ ¹ ^3�n� Ä£h ��} gic �&�Brn}"ts] c \§��t h \"]&r mlfmimid �À¥V¥��I�I� � _ �it � � gihv� _ cV� ¥n\�]?[ � rV\"\R¥ h tstk["� mig r mih {V] �·l'mi� t�rV\"w h \Ãx mid x c3g�� x c3g _ c3�Zd r _ m&d�gih \ mih \ jx mBd �À¥3¥¸x mBd1� _ ��t � � gihK� _ c3� ¥ d ["}R¥�["�i] g � ¥�\"]?[ � rV\"\�¥ h tkts["� mBg r mBh {V] �·d �IrV\�wx mBd �À¥3¥¸x mBd1� _ ��t � � gihK� _ c3� ¥ d ["}R¥�["�i] g � ¥�\"]?[ � rV\"\�¥ h tkts["� mBg r mBh {V] �·d w§x �

~ º#mil ] gI� \ c �&\ _ rV�i]z� l r�{V]�}�]?]z\ g ] d�c3g�m ]?w h \�x c3g�� rntst e u§}�[ m \ cVm w c _ [ � ]?\ m ]?w d ["}"t h _ t e3�¦� o c3� ]_ rn�i]?� c xR\ c \"��[ g { h { h \ j � e � m ] � � r g ]½r m�mBgih }"[ m rV}"ts] mBc � c x m �Nr g ]5³Rr��&� h \ mBg�c w"[ _ ]?w;} e � e � m ] � w"]?� hsj \1u} e � e � m ] � � c x m �½r g ]µw"]z{V]?t cVd"� ]z\ m u cVg } e � r h \ m ]?\�rV\ _ ]Vu5r m {nr g�hsc ["� d�c3h \ m � h \ mBl ]y� e � m ] � t h x®]_ e _ ts] � o c3� ]��N] g ]Dw"["] mBcZl r g w��½r g ]Vu cVmil ] g � mic ]?\f{ hsgic \ � ]z\ m rVt�x r _ mBc3g �¯��[ _ l rn�¯]zts] _ mBg�c3� r j \"] mBh _g rnw h r mihsc \�u cVmil ] g ��� hs�Zd t eZmBc�l [ � rV\Ãx c3h }�ts]?� �

� rVt h _ hsc ["�#� e � m ] � �­h �i["��] h �¶rÃ{3] g9e �i] g�hsc [�� d�cVm ]?\ mBh rVt d"gic }"ts] � ~ ]z� d ] _ h rVtst e � l ]z\ hÂm _ rV\ g ]���i[�t m¶h \©� e � m ] � rV\"w²\"] m � cVgi� _ c tst|r d �i] � u�rVt mBl"c [ j3l©�Zc � m�c x mil ] d ]z\"] mig r mihsc \©]�» cVg�m � g ] _ c3g w"]zw micw�r m ]��N] g ]�r mim r _ � � c \ _ c3�­d [ m ] g � e � m ] � � mil ] � �i]ztk{3]z� g r mBl ] gImBl rn\ c \ _ gihkmih _ rVt1r d�d t h _ r mihsc \"� mBl r m["��]?w _ c3�­d [ m ] g � �½� ]z{V] g9mBl ]zts]?���?u£�i] g�hsc [�����] _ [ gihkm�e {P["tk\"] g rV} h t hkmih ]z�½]�¢ h � m#h \ � rV\ eÃ�Zh ��� hsc \§� _ gihkmih _ rVt� e � m ] � �?u � rV\ eÃc x)� l"h _ l _ c ["tsw g ]z�i["t m¯h \Ãt c �i� c x �i[ g { h {nrV} h t hkm�eV�¿�hkmil rntst mBl ]�x®[ g�c3g�c {V] gFd ]?\"] mBg r mBhkc \"� c x ¿ ]?} � hkm ]z�?u w"]?\ h rVtÂ� c x|����] g { h _ ]Zr m�m r _ � �?u rV\"w d"g�c3d r��

j r mih \ j � gic � rV\ l�c3g ��]?� h \ ]�� � r h tvu�w�]?] d ] g�h �i�i[�]?�Z�i]?] � t c � m�h \ mBl ]µ� l [��Z] � q�\ mil ] _ rV��] c x mBl ]d ]?\"] mBg r mBhsc \"��rV\"w4w h � mBgih }"[ m ]?w w"]z\ h rVt � c x|�¼�i] g { h _ ]�r m�m r _ � �zu hkmFh � c }f{ hsc ["� mBl r m�c3d ] g r mBh \ j � e � m ] ��i] _ [ g�hkm�e rn\"w�\"] m � c3gi�'h \ j�g�c }"["� m \"]z�i�µr g ] h \�rVw�]� '[�r m ] � q�\ mBl ]�]�� � r h t _ rn�i]?�zu mBl ]ª{§[�ts\"] g rV} h tÂ�hkmih ]z� ]�¢ d t c3hkm ]?w h \ mil ] � o ¿4c3g w � r _ gic { hsg ["� h \ � h _ g�c � c x m�º [ m t cPc3� rV\"w º [ m t c§c3��� ¢ d"g ]z�i�l r�{3]Ã}�]?]z\ r gic [�\"w x c3g rªt c \ jµmBhs� ] rn\"w r g ]�t hs� ]?t e©mBc }�]Ãr gic ["\"w x c3g rªt c \ j�mBhs� ] � �#t mil"c [ jVl� cV� ] d rVtkt h r mBh {3]«±�¢§]z�«r g ]4r�{nr h t|rV}"tk]Vu mBl ]�x®["\�w�r � ]?\ m rVt d�gic }"tk] � � g ] � r h \ � ¡ cVg ]�¢�r �Zd ts]nu#±�tÂ�m ] g �µw"]?tk] mih \ j ]�� � r h t�� hÂmBl �Bo§["} � ] _ m ��q �Zd�c3g�m rV\ m � ]?�i�ir j ]²x gic3� �k�Â� � r g ] c \"t e d r g�mih rVtkt e ["�i]��x®["tKu h \ t hkj3lfm�c x�{Vr gih rn\ m {3] g � hkc \"� c x � ]zt h �i�Br�� hkmBl oP["} � ] _ m � t h \"]z� mil r m r g ]ªw h »�] g ]?\ mÃcVg ]z{V]?\}"tsrV\ �R� � l ]F�Br � ] d�gic }"tk] � g ] d ]?r m ]zw hkm �i]?tÂx�r e ]�r g t|r m ] g � hkmBl q� º ��� � º ¬ rV\"w hÂm �#��["}"��]� '["]?\ m_ t c \"]z� � � l ]�}�rV� h _ � e � m ] � h \�x g rV� mig [ _ m [ g ] h � h \ _ r d rV}"tk] c x�rVw�]� '[�r m ]?t e«d"gicnm ] _ mBh \ jÃhkm �i]?tÂx�r j r h \"� mrVtkt �'h \"w�� c x �­h �i["��]?�?u�rV\�w mil"h � d r g�mih _ ["t|r g ]�¢ d t c3hkm;h � � ["� m rV\ cVmil ] gFg ] �Zh \"w�] g;mil r m�� rV\ e x c t � �\"]z]?w mBc �½r � ]Ã[ d1� � l ] � hkm ["r mBhkc \ _ c ["tkw l r�{3]Ã}�]?]z\ � [ _ l � c3g �i]Vu�}�[ m ["\§x c3g�m ["\�r m ]?t e�� rV\ e²c xmBl�c �i] � l"c w"] d ]z\"w c \ � e � m ] � � mBl r m r g ] h \ l ] g ]?\ m t e h \�rVw"]� P["r m ] w c \ cVm�j ] m�mBl ] d"g�c3d ] gF� ]?���Br j ]?��� l ]?\ mBl ]ª� hÂm [�r mihsc \ h � � � � r m ] g�gih }"ts]µw h �irV� m ] gz�0º \ mBl ] cVmBl ] g�l rV\"w1u&]z{V]?\ h x��N]ª�5] g ]mBc l r�{3] m ] g�gih }"ts]Ãw h �BrV� m ] g �?u hÂm r d"d r g ]?\ m t e � c ["tsw \ cVm }£]µ]?\ c [ j3l1� � rV\ e�c x mBl ] _ c \"� mig [ _ mBh {V]ts]z�i� c \"� mBl r m � l�c ["tsw l r�{3] }£]z]?\ ts]?r g \�]?w x g�c3� p c }�] g9m � r d"d rV\ � cVgigih � � �ªq�\ m ] g \"] m�¿ c3g�� h \�T�3�V�ÃrV\"w²�i["}��i]� '["]z\ m ]z{V]?\ m ��r g ]�� mBh tst ["\"ts]?r g \�]?w � ~Ko§]?] �;e �T�3�f Pu �T�3�3�§u�rV\"w ^VX3XVX m ]?� mBhk�­c \ h ]?�x c3g mil ]#¬ � o � ( c ["��]�YV[�w h _ h r g9e�aNc3�Z�­hÂmim ]?]Ir m�lfmimid �¦¥3¥��I�I� � _ �it � � gihK� _ c3� ¥�\"]?[ � rV\"\�¥ l"c ["��]��f  �ÁlfmB� tvulfmimid �À¥V¥��I�I� � _ �it � � gihv� _ cV� ¥n\�]?[ � rV\"\R¥ l"c ["��]��3� �·lfmB� tvu lfmimid �À¥V¥��I�I� � _ �it � � gihv� _ cV� ¥n\�]?[ � rV\"\R¥ l"c ["��]�X3X �·lfmB� tvug ]z� d ] _ mBh {V]?t e u�� l"h _ l w h � _ [��i� mBl ]Dr � r �?h \ j t|r _ � c x d"gic3jVg ]?���¯x g�c3� c \"] e ]�r g¯mic�mil ]¶\"]�¢ m?��¿ gihÂmim ]z\rV\"�9�N] g � mBc p&] d"g ]?��]?\ m r mih {V]?� � '["]z� mBhkc \"� c \ mil ]&�T�3�f  m ]?� mBhs�Zc \ e r g ] rVtk� c½c \P��t h \"]V� l'm�mBd �¦¥3¥��I�I� � _ ��t � � g�hv� _ c3� ¥n\"]z[ � rº \"] c x mBl ] � r ��c3g tk]?�i� c \"� h \f{ c tk{V]?� mBl ] g�h � ��c x �Zc \ c _ [�t m [ g ]?�zu mBl r m&h �zu d [ m�mBh \ j rntst eVc [ g ] j3j �

h \ c \"] }�rV� � ] m � d r g�mih _ ["t|r g t e � l ]z\ mil r m }"rV� � ] mZh � h \ l ] g ]?\ m t e {P["tk\"] g rV}"tk] � � �i] _ c \"w ts]z�i� c \h � mil r m � l ]z\©r d£cVm ]?\ mBh rVtst e w"rV\ j ] gic ["�&{P["ts\�] g rn} h t hkm�e­h �&]�¢ d t c3hkm ]?w h \µr g ]?tsr mBh {3]zt e l r gi� ts]z�i�I�½r e ud"g�c r _ mih {V] � ]�rV��[ g ]z��� l"c [�tswF}�] m r � ]z\ mic r�{ c3h w � [ _ l�jVg ]�r m ] g w�r � r j ] h \ mil ]Nx®[ m [ g ] � � l ] � ]?t h �i�irrV\"wµq� º ��� � º ¬ � a { hsg ["�i]z��} cVmil ]�¢ d t c3hÂm ]?w mil ]�� _ g�hsd�mih \ j _ r d rV} h t hkmih ]z� c x � h _ gic � c x m�º [ m t c§c3�R�� l ]¯t|r m�m ] g _ rV��]�� l"c ["tkw l rT{V]#}�]?]z\­\ c �i[ gid"g�h �i]nu§}�[ m mBl ]&w�r � r j ] _ c ["tkw l rT{V]#}�]?]z\ � [ _ l�j3g ]�r m ] g?�

� �

Page 47: Practical Architectures for Survivable Systems and Networks (Phase

� mBl"hkg w�ts]?��� c \ h � mBl r m �5] l rT{V]�� mBh tkt \ cVm �i]z]?\ ]z\ c3g��­c [��it e w"]?� mBg [ _ mBh {3] � a { hkg ["��]?�?u rV\"w l rT{V]c \"t e }£] j ["\ mic ±�\"w d�c t eP�Zc3gid�l"h _ d ]?� m½d"gic3jVg r � � mil r m _ rV\ mig rV\���x c3g��*mil ] � �i]ztk{V]?� _ c \ mih \'[�rVtkt e�h \c3g w"] gImBc�l"h \"w"] g w"] m ] _ mihsc \ �

(*) � � � ���§���b� ,�-����;�)�����

´Ng ]�r � w c �&\"� h \�� e � m ] � �i[ g { h {nrV} h t hkm�e r g ] c x m ]z\Ãr mimigih }"[ m ]zw mBc ] hÂmBl ] g �i] _ [ g�hkm�e­d"gic }"ts] � � c3g5g ]?t h r��} h t hkm�e�d"g�c }"ts] � � � ( c �N]�{3] g u mil ] g ] h ��rV\ h \ m ] g ]?� mBh \ j _ gic ��� c {3] g }�] m �5]?]z\ mBl ] m � c¯m�ePd ]?� c x d�gic }"tk] � �?u� l ] g ]?} e _ rV[��i]?�NrV\"w­]z»£] _ m � � r e }£] g ]zt|r m ]?w­rV\"w h \­� c3� ] _ rV�i]z� h \ m ] g��­h ¢�]zw � � l ]&x c tkt c � h \ j ]z\'[§�� ] g r mBhsc \«�i[ j3j ]?� m � mBl�h � _ c [ d t h \ j"� q m�h tstk["� mig r m ]?� mBl ]Fw h � mih \ _ mBhkc \"��rn\"w©� hk�­h t|r g�hkmBh ]?�I}�] m �5]?]z\ mBl ]m � cZm�ePd ]?�?u�rV\�w j3h {3]z��r d"g ]?t hs�Zh \�r g9e { h ]z� c x¾� c3� ] c x mil ] h \ m ] g w"] d ]z\"w"]?\ _ h ]z� �

� M�>§L H®<��¾H L H®S !�O)Q�E � L >�� =«ST:)<�S²<"LK=?E 3E�� L�%�:)<���> ��>'>PJ =?>����QnH S !0O)Q�E � L >�� = � q�\ � c3� ]_ rV�i]z�?u�x r h tk[ g ]z� mil r m#l r�{3]F}�]?]z\ mBg r _ ]zw mBc � e � m ] � g ]?t h rV} h t hÂm�e�d"g�c }"tk] � � _ c ["tsw«rVt m ] g \�r mBh {3]zt el rT{V]�}£]z]?\ _ rn["�i]zwµ} e�� rVt h _ hsc ["� l [ � rV\yr _ mihsc \�� � ¡ c3g ]�¢�r �­d ts]Vu§} cnmBl�mil ]D^3  º _ mic }£] g �T�3�VX�#p � �#\"] m _ c tkt|r d �i]½rn\"w mBl ]��T��Y3rV\'[�r g�e �T�3�3X�� � � � _ c tkt|r d �i] _ c ["tkw l r�{3]&}£]z]?\ � rVt h _ hsc ["�it emigihkj3j ] g ]?w1uPrVt mBl"c [ j3l­mil ]#� e � m ] � l r g w��Nr g ]#rV\"w � c x m �Nr g ]#³�rT�&� mBl r m5d ] gi�Zhkm�m ]zw mBl�c �i] d"gic }P�tk] � �1�N] g ]5rVt g ]�rVw e�h \ d tsr _ ]nu h \�rVw�{V] g�m ]?\ m t e3� q�\ mil ]�x cVgi� ] g _ rn�i]Vu hkm � c ["tkw l r�{V]N}�]?]?\ d£c �i� h }"ts]mic�� rVt h _ hkc ["��t e�h \"��] g�m } c3j ["��� m r m ["� � ]z�i�ir j ]?� h \ mBc¶mBl ]�\ c w"] mBg r _ u§rV\"w _ g ]?r m ]�]�¢�r _ m t e�mBl ]�ir � ];]z»£] _ m�c x��ir m [ g r mih \ j ]�{3] g�e \ c w"] h \ mil ];\�] m � c3gi�R� q�\ mBl ]Ft|r m�m ] g _ rV�i]nu � ]z[ � rn\"\«�NrV�mic tsw4} e4m � c²e3c [�\ j²h \ mBg ["w"] g ��� l"c3g9m t e rnx m ] g �Nr g w mil r mFmil ] e l rVw }£]z]?\ ]�¢ d ] gihk� ]z\ mBh \ j©c \mil ]¶± g � m ��� hÂm _ l � l ]?\ mil ] h \ hkmih rVt _ g rV� lªc _?_ [ gig ]?w �£h \ mBl r m _ rV�i]nu hÂm�h � _ c \ _ ] h {nrV}�ts] mBl r m¯mBl ]r _ � \ c �&tk]?w j ]?w g ]zt h rn} h t hkm�e d"gic }�ts] � � r e r _ m [�rntst e l rT{V]©}£]z]?\ migihsjVj ] g ]?w rV��rV\�r _z_ h w�]?\ m rVt} ePd"g�c w"[ _ m½c x)r��i] _ [ g�hkm�e­d ]z\"] mig r mihsc \ � h x mBl ] eZl rVw _ rV["��]?w mBl ] h \ hkmBh rVt _ g rV� l1� q�\"w"]z]?w1u�rn\ ew h � migih }"[ m ]zw²� e � m ] � � hkmil g ] �ZcVm ] � r h \ m ]?\�rV\ _ ]�x r _ h t hÂmBh ]z� l rn��� hs� ["t m rV\�] c ["� d�cVm ]?\ mBh rVts�#x cVg[�\ g ]zt h rn} h t hkm�eµ�­c w"]z�;rV\�w � rVt h _ hsc ["� _ cV�­d"g�c3�Zh �i]z� � g ] �ZcVm ] � r h \ m ]?\�rV\ _ ] h �¶{3] g9e _ c3�Z�­c \h \ � rV\ e � e � m ] � �?u h \ _ tk["w h \ j { h r w h rVtÂ�¼[ d t h \"]z��rV\"w©q�\ m ] g \"] m r _?_ ]?�i��~ h \©rVw"w hkmBhkc \ micÃl r g wP�� hkg ]zw _ c \"\�] _ mihsc \�� ��� o hk�­h t|r g t e u mBl ] g ] l r�{3]�}�]?]z\ � rV\ e�h \�rVw§{3] g9m ]z\ m _ rV�i]z� c x5r _?_ h w"]z\ m rVtkt e��]z{V] g ]zw _ rn}"ts]z�¶� l ] g ] mBl ]­�ir � ]�]�»�] _ m _ c ["tkw l r�{3]Z}£]z]?\ r _ l"h ]�{3]?w h \ m ]z\ mihsc \"rVtst e � h x c \�]� \"]�� � l ] g ] mBc w hkj"��º \ _ ]­rn\ r _?_ h w"]?\ m rVtst e ]�¢ d t c3hÂm rV}"tk]�{P["tk\"] g rV} h t hkm�e }£] _ c3� ]?� � \ c �&\1u hkm� r e }�] g ]?tsr mBh {3]zt e ]�rV� eÃmBc _ g ]�r m ]D� hs�Zh tsr g _ c \"w hÂmBhkc \"� � rVt h _ hsc ["�it e3�

� ��>���)Q�H S !bO)Q�E � L >�� =ZS¸:)<§S 3E �)L�% <�L =?E�:)<���> ��>P>PJ Q¸>PL H <�� H LKH S !�O)Q¸E �¾L®>�� = � q�\ _ ] g9m r h \_ rV�i]z�?u�� e � m ] � w h � g [ d�mBhkc \"� mil r m¶l r�{V]­}�]?]z\ mig r _ ]?w mBcy� rnt h _ hsc [�� l [ � rV\�r _ mihsc \�� _ c ["tkw�rVtÂ�m ] g \�r mBh {3]zt eyl r�{3];}£]z]?\ _ rV["�i]zw©} e�l r g w��Nr g ] c3g � c x m �Nr g ] � rVtÂx®["\ _ mBhsc \"� � � l�h � h ��]z� d ] _ h rVtkt emig ["]¶� hkmil w"]z\ h rVt � c x|�¼�i] g { h _ ]�r mim r _ � � h \µ� l"h _ l rn\ h \ m ]?\ mBhkc \�rVtkt e ]�¢ d t c3hÂm ]?w�� h \ j ts]��5]�r � t h \ �_ c ["tkw � ["� m rV���5]?tkt l r�{3]Fx r h ts]zwªr _z_ h w"]?\ m rntst eV� q m�h �#]�{3]?\ mBg ["];� l ] g ] � ["t mihsd tk]D]�{3]z\ m � _ c ["tkwl rT{V]�}�]?]z\ migihkj3j ] g ]?wy} e r�� h \ j ts]�["\�w"] g t ePh \ j _ rV["�i] � rV� _ c ["tsw l r�{3]D}�]?]?\ mBl ] _ rV�i] h \ mBl ]o§rV\ ¡ g rV\ _ h � _ c²d£c �5] g�c [ m r j ]y\ cVm ]?w rV} c {V] h x mBl ] g ] l rVw }£]z]?\�r d"g ]�{ hkc ["��t e ["\ h w"]z\ mih ±�]zw_ c3�Z�­c \P� �Zc w"]¯x r h tk[ g ] �­c w"] mil r m r _?_ h w"]z\ m rVtkt eZmBgihkd"d ]?w � ["t mBhsd ts]#�9� hkm _ l ]?� �

� M�>§L H®<��¾H L H®S !²O)Q�E � L >�� =DS¸:)<§S�<"Q¸>«L®>P=�=FL H � >PL !�STE�E&����QZ<"=Z=z> ���Q�H®S !4O Q¸E �¾L®>�� = � o c3� ]_ rV�i]z� l rT{V] g ]?��["t m ]?w x gic3� rV\ c }"� _ [ g ] _ cV� } h \"r mBhkc \ c x � rVtÂx®["\ _ mBhsc \"� c3g�cVmil ] g�g ]?t h rV} h t hkm�ed�gic }"tk] � � mil r m _ c ["tsw \ cVm�g ]?rVt h � mih _ rntst e«l r�{3]µr g�h �i]z\ x gic3� � rVt h _ hsc ["� l [ � rV\ r _ mBhkc \"� � ¡ c3g]�¢�r �­d ts]Vu h \ mil ] ��p � ��\"] m _ c tstsr d ��]Vu mil ] g ]��½rn��r«x®["\"w�r � ]?\ m rVt5w�]?� hkj \ w"] _ h � hsc \ mBc©c3�Zhkm

� �

Page 48: Practical Architectures for Survivable Systems and Networks (Phase

l r g w��Nr g ]�� hk�­d ts] � ]?\ m ]?w d r gihÂm�e _ l ] _ �'h \ j�c x�� mBc3g ]?w � m r m ["��� c3g w"� ~ d r gihÂm�e _ l ] _ �'h \ j �NrV�d�g ]?��]?\ m x cVg�mBg rn\"� �Zh ��� hsc \"� � u¾rV\�w4rÃ�N]?r �²j r g }�r j ] _ c tsts] _ mihsc \²rVt j3c3g�hkmBl�� h \ � c x m �½r g ] � � l ]g ]?��["t m �NrV� _ tk]�r g t e r²\�] m � c3gi� �¼� h w"] g ]?t h rV} h t hÂm�e²d"gic }"ts] � mBl r m �½rn�Z[�\"t hk� ]?t e4mic�l rT{V]y}£]z]?\_ g ]?r m ]zw h \ m ]?\ mBhkc \�rVtkt e rV�Nr � gic�� rV\ l"c3g �i] c3g h \"� m rVtkts]?w�w e \�r �­h _ rVtkt eDmBl"g�c [ j3l rD��] _ [ gihÂm�e­d ]?\P�] mBg r mBhkc \ � � l ] g ]��5] g ] � [ _ l ]�rV� h ] g �½r e � mBc;mig rV� lÃmBl ]�\�] m � c3gi�R� ~ º \ mBl ] cVmBl ] gIl rV\"w�u c \ _ ]mil"h � {§[�ts\"] g rV} h t hÂm�e;l rnwZ}�]?]z\ g ] _ c3j \ h�� ]?w�u hÂm � c ["tsw l r�{3]&}�]?]z\Z{V] g�e ]?rV� e;mBc�mBg�hsj3j ] g¾mBl ]¯�ir � ]x r h ts[ g ] �Zc w"] � rVt h _ hsc ["�it e u"rn��\ cnm ]?w h \ mil ]¶± g � m }"["tkts] m ]?w hkm ] � h \ mBl�h �¯�i] _ mBhkc \ �¦� o hk�­h t|r g t e umil ] � r migihkcVm��Zh �i� h tk] _ t c _ � �¼w gih x m�d"gic }"ts] � �½rn�­r©��["} m tk] hs�Zd ts] � ]z\ m r mBhkc \4³Rr�� mBl r m � c ["tkw\ cVm t hs� ]?t eÃl r�{3]D}£]z]?\ _ g ]?r m ]zw h \ m ]?\ mBhkc \�rVtkt e � ["\�ts]?��� mil ]Dw"]z{V]?t cVd"� ]z\ m�d"g�c _ ]?�i� hkm �i]ztkx l rVw}�]?]z\���["}f{3] g9m ]zw ��mBl ]¯{P["tk\"] g rV} h t hkm�e �½rV� x r hkg t e �i["} m ts]nu�rn\"w�r gic ��] c \�t e }�] _ rV["�i] c x d�gic t c \ j ]zw[��i] c x mBl ] �­h �i� h ts] d t|r m x c3g�� � h \ mil ]��Br � ]�t c _ r mBhkc \1uf� hkmil"c [ m½mil ]�]�¢ d ] _ m ]?w g ] h \ hÂmBh rVt h�� r mihsc \ �� ]z{V] g�mil ]?tk]?���?u h \y�i[ _ l _ rV��]?� c x c }"� _ [ g ] d"g�c3j3g r �­�Zh \ j }"[ j �zu hkm&h � d�c ��� h }�ts] mBl r m rZw h � jVg ["\§�m ts]zw d"g�c3j3g r �­� ] g _ c ["tsw l rT{V] d tsrV\ m ]?wªr � [ _ l � hs�Zd ts] g ["\"w"] m ] _ m rV}�ts] � gic�� rn\ l"c3g �i] h \ mBl ]� c x m �Nr g ] mBc r _ l�h ]z{V] _ c3�Zd r g rn}"ts] g ]?��["t m � �

� ��>���)Q�H S ! O Q¸E � L >�� =;S¸:�<�S�<"Q¸>«L >P=�=�L H � >PL�!4STE�E&����Q­<�=�Q¸>PLKH®<�� HKL H®S !�O)Q�E � L >�� = � a rV��]?�mil r mDg ]z�i["t m x g�c3� ]�¢ mig ] � ]zt e ]?tsrV} cVg r m ] � rVt h _ hsc ["� l [ � rV\4r _ mihsc \���r g ] � [ _ l tk]?���;t hk� ]zt e«mic}�] _ rV["��]?wÃ} eZ� rVtÂx®["\ _ mBhsc \"� � ¡ cVg ]�¢"r �­d tk]Vu _ c \�� h w�] g r _ c3�Zd t h _ r m ]?wZ�i]� P[�]?\ _ ] c x��i[ _z_ ]z�i� h {3]d ]?\�] mBg r mBhkc \"�yrV\�w � rV\ hkd ["tsr mBhkc \"� c x d�gic3j3g r � �ÃrV\"w w�r m r�~ ] �·j"� u _ g r _ �'h \ j u l r _ �'h \ j u�rn\"w� gic � rV\ l"c3g � h \ jf� u g ]?t ePh \ j r m ]�r _ l � m ] d�c \ � \ c �&ts]?w j ] j r h \�]?wÃx gic3� mBl ]¶]�» c3g9m � mil [��¯x r gz� q�\��[ _ l _ rV��]?�zu'x g ]�r � r _?_ h w"]z\ m � r g ] � [ _ l ts]z�i� d"g�c }�rV}"tk] mil rV\ h \ m ]ztst hsj ]z\ m t e _ c§cVg w h \�r m ]zw�r mim r _ � �~ rV� h \ mil ] _ rV��] c x mBl ]D��["� mig rVt h rV\Ã�irV} cVm r j ]�\ cVm ]zw«rn} c {3] ���

q�\ mihs� ] c x _ gih � h �zu mBl ] g ] _ rV\Z}£]¯["\ _ ] g�m r h \ m�eZc {3] g � l ] mBl ] g r d r g�mih _ ["t|r g ��[ g { h {Vrn} h t hkm�eFd�gic }"tk] �h � g ]?tsr m ]zw mic �i] _ [ gihÂm�eyc3g½mBcZg ]zt h rV} h t hkm�e u§r�{nr h t|rV} h t hÂm�e u'rV\"wyx rV["t m½mBc ts] g rV\ _ ] �

� � m¾mBl ] mihs� ] c x mil ] � ]�r g �9^VXVX3X � gic }�ts] ��gic tst c {V] g u3r � rVt h _ hsc ["����] _ [ gihkm�e r mim r _ � _ c ["tkw�}£]N{V] g9ew h _ ["t m½mBc w h � mih \ j [ h � l x g�c3� rFx r h ts[ g ] mBg�hsj3j ] g ]zwµ} e mil ] � ^V° d"gic }�ts] � hkm �i]?tÂx �

� � g ]z{3]z\ mBhsc \�r j r h \"� m w"]z\ h rVt � c x|�¼�i] g { h _ ]5r mim r _ � � h � m�e§d�h _ rntst e _ c \"� h w"] g ]zw mBc }�]½r��i] _ [ gihÂm�eDd"gic }P�tk] � u�� l ] g ]?rV� w"]z� hkj \Fx c3g)l"hsj3l � e � m ] � rT{nr h t|rV} h t hÂm�e#h � _ c \"� h w"] g ]?w mic }£]Nr g ]zt h rV} h t hkm�e�d"gic }"ts] ���a tk]�r g t e u mBl ] e r g ] _ t c �i]zt e­h \ m ] gig ]?t|r m ]?w � q�\µ� c3� ] _ rV��]?�?u � rVt h _ hkc ["��w"]?\ h rVt � c x|�¼�i] g { h _ ]#r mim r _ � �� r e }£] h \�w h � mBh \ j [ h � l rV}"tk]½x gic3� r _?_ h w"]?\ m rVtRw"]?\ h rVts� c x��i] g { h _ ]nu h \�["\"w�] g t ePh \ j _ rV["��]?�NrV\"w h \mil ] hkg ]z»£] _ m � �

� � g�cVm ] _ mBh \ j r j r h \"� m ]zts] _ mBg�c3� r j \"] mih _ h \ m ] g x®] g ]?\ _ ] l rV�©r mimBg�h }"[ m ]?� c xZ} cVmil �i] _ [ g�hkm�e rn\"wg ]?t h rV} h t hÂm�e u }�] _ rV["�i] hkm _ c ["tsw c _z_ [ gZ� rnt h _ hsc [��it e ~ � r �­�Zh \ j'��c3g r _z_ h w�]?\ m rVtkt e ~®] �·j"� uIr mB�Zc �� d"l ] gih _ g rnw h r mihsc \�uft hsjVl'm \ h \ j u _ hkg _ [ hkm ] � rV\�r mBhsc \"� ��� o§[ _ l�h \ m ] gig ]zt|r mihsc \�� l"hkd � r g ] _ c \"� h w"] g ]?wh \ aNl r d�m ] g W �

¡ [ g�mil ] g��­cVg ]Vu h \ _ ] g9m r h \ _ rV��]?� hkm�� r e \ cVm }�]©]z{ h w�]?\ m � l ] mil ] g r d r g�mBh _ ["tsr g r mim r _ � �NrV�\�r m [ g rnt c3g l [ � rV\ g ]?t|r m ]?w � rV\"w h x l [ � rV\1u&� l ] mBl ] g r _?_ h w"]z\ m rVt c3g�h \ m ]z\ mihsc \"rVtvu � rVt h _ hkc ["�c3g�cVmil ] g � h ��] � q�\"w"]z]?w1u mBl ] g ] h ��t c \ j ��� m rV\"w h \ j ]z{ h w"]?\ _ ] mBl r m¶h \ mBg [�w"] g ��~ � _ g r _ � ] g � �'�¶l rT{V] l rVwr _z_ ]?��� mic mil ] m ]?tk] d"l�c \"]²��� hÂm _ l ]z�?uDrV\"w _ c [�tsw l r�{3] _ rV["��]?w g ]?��["t m � cVmBl ] g � h �i] r mimigih }�[ m ]zw mic� e � m ] � d"g�c }"ts] � � � �#�D\ cVm ]?w rn} c {3]nu mil ]«�¸�µY3rV\'[�r g9e �T�3�3Xy� � � � c [ m r j ] � r e r _ m [�rVtkt e©l rT{V]}�]?]?\ mBg�hsj3j ] g ]zwy} eyh \ mBg [�w"] g �?uRrVtk}£] hkm r _z_ h w"]?\ m rntst eV� � l ] g ] h �&rVts� c rV\µ["\f{3] g�h ±�]zw«� m r m ] � ]?\ m¯� rVw�]

` �

Page 49: Practical Architectures for Survivable Systems and Networks (Phase

} e rV\ ¡ ´ qNr j ]?\ m w"[ gih \ j r m rVt � r m½mBl ]¶¬¯\ h {V] g � hkm�e�c x a rVt h x c3g \ h rDr m ¨�r�{ h � micFmBl ]�]�»�] _ mImil r mImBl ]^�YV["t e �T�3�f  ¿ ]?� m�aNc rn� m¯d£c �5] g&c [ m r j ] h \'{ c tk{V]?w�� c3� ] � rnt h _ hsc [��it e _ rV["��]?w«]�{3]z\ m � ��#�Fx®[ g�mBl ] g ]�¢�r �Zd tk]?� c x mBl ] x®[ ����e _ g�c �i� c {V] g }�] m �5]?]?\ g ]zt h rn} h t hkm�e rV\�w ��] _ [ gihÂm�e

rVt mil"c [ jVlw hkg ] _ m ]zw �­cVg ] mBc �½r g w ��[ g { h {nrV} h t hÂm�e©c x h \ m ] j3g�hkm�e²g ]� '[ hsg ] � ]?\ m � mBl rn\ mBc �Nr g w ��[ g { h {Vrn} h t hkm�e � ���� � � mBl ] g ] l r�{3]­}£]z]?\ \'[ � ] g�c ["� _ rV�i]z� c xN�i["� d"h _ hsc ["��r _ mBh { hÂmBh ]z� h \f{ c tÂ{ h \ j _ c3�Zd [ m ] g ��["��]?w h \]?tk] _ mBhsc \"� � q�\ c \"] _ rn�i] h \ d r g�mih _ [�t|r g u mBl ] g ]?��["t m � c x mBl ] d�g ]?t hs�Zh \�r g�eÃm ]z� m¶d"g�c _ ]?��� h \ j �5] g ]�ts]zx m["\"w�]?ts] m ]zw1u�rV\"wyr _ m ["rVtst e � c [�tsw l r�{V] _ rV["��]?w mBl ]#� gic \ j � h \"\"] gNmBc }£]�]zts] _ m ]zw1u l rVwyrV\yrV\ cV� rVt e\ cVm }�]?]z\4w"] m ] _ m ]zw � �#t mBl"c [ j3l©mBl"h ��] gig�c3g �NrV��]�{3]z\ m [�rVtkt e w h r j \ c �i]?w�rV\�w _ c3gig ] _ m ]?w1u mil ] _ t|r hs��NrV� c x _ c [ g ��] � rVw�] mBl r m&mil"h �½�NrV�¯rV\�r _?_ h w"]z\ m?� ( c � w c�e3c [ � \ c � hÂm �½rn��\ cnm&h \ m ]z\ mihsc \"rVt �� l ]Ãx c3g ] j3c3h \ j w h � _ [��i� hkc \ rVts� c r d"d t h ]?� mBc²d ] g x c3g�� rn\ _ ]Ãw"] j3g rnw�r mBhkc \"��rV�F�5]?tkt&rV� _ c3�Zd tk] m ]

c [ m r j ]z� � � l ]Ã]z{ h w"]z\ mFl ] m ] g�c3j ]z\"] hÂm�e c x _ rV["��]?��rV\"w4]z»£] _ m ���i[ jVj ]?� m � mil r m � e � m ] � ��� l"c ["tkw }�]w"]�{3]?t c3d ]?w mBc rV\ mih _ hkd r m ]�rF} g�c rVw"] g _ tsrV�i� c x mil"g ]?r m � � \ cVm � [�� m½mic \�r gig�c �&t e rVw"w g ]?�i� mil"g ]?r m � mic�i] _ [ g�hkm�e u c3g mic�g ]zt h rn} h t hkm�e u cVg mBc#d ] g x c3g�� rV\ _ ]VuV}"[ m g r mBl ] g¾mic rVw"w g ]?��� mBl ]5\"] _ ]?�i�ir g�eFg ]� '[ hkg ] � ]z\ m �h \ mil ]¶�Br � ] _ c \ m ]�¢ m���#\ c }'{ hkc ["� _ c \ _ tk["� hkc \ c x mil"h �½w h � _ ["�i� hsc \ h � mil r m � e � m ] � �I� l"c ["tkwÃ}£]�w�]?� hkj \"]zw mic }£]#�i[ g { h {f�

rV}"tk]Vu mBc � hÂmBl � m rV\"w } cnmBl r _?_ h w"]z\ m rVt � rVtkx®["\ _ mBhkc \"��rn\"w h \ m ]?\ mihsc \�rntst e _ rn["�i]zw c [ m r j ]z� cVgDcnmBl ] gw"]�{ h r mBhkc \"�½x g�c3� w"]z� hkg ]?wy}�] l r�{ hscVg?� o§[ g { h {nrV} h t hkm�eZh \ m [ g \ g ]� '[ hsg ]?�¯rF{Vr gih ] m�e c x)x®[ g9mBl ] gIg ]� '[ hkg ]��� ]?\ m �zuPx c3g ]�¢�r �Zd tk]Vu g ]zt|r mih \ j�mBc �i] _ [ g�hkm�e u g ]zt h rn} h t hkm�e uVrV\"w gic }"[�� m \�]?�i� c x _ c3�­d�c \"]z\ m �?u§\"] m � c3g�� �zurVt j3c3gihÂmBl"� �?u hs�Zd tk] � ]?\ m r mihsc \��?u§rV\"wµ� c�c \ �

`¸Å

Page 50: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� � ����� ��� � � � � � � ��� � � � � � � �

� [ � ] gic ["��{P["tk\"] g rV} h t hkmih ]z�?u mBl"g ]�r m �?u�rV\�w g�h � � ��r g ]�]z\ _ c [�\ m ] g ]?w h \²r m�m ] �Zd�mih \ jZmBc w"]�{3]?t c3d u c3d �] g r m ]nu1rV\�w � r h \ m r h \�� e � m ] � ��� hÂmBl � mBg�h \ j ]?\ m �i[ g { h {nrV} h t hÂm�eÃg ]� P[ hsg ] � ]z\ m � � �#tst mil ]?��]�� c [ g _ ]z� c xrVw�{V] g � hkm�e _ rV\ g ]?�i[�t m­h \ � e � m ] � rV\"wbr d"d t h _ r mihsc \ ��[ g { h {Vrn} h t hkm�e }�] h \ j ["\"w"] gi�Zh \"]zw � � l ]µ�i] _ �mBhkc \"� c x mil"h � _ l r d�m ] g _ c \�� h w�] g#mil"g ]?r m � mBc ��] _ [ gihÂm�e u g ]zt h rV} h t hkm�e u£rn\"w d ] g x c3g�� rV\ _ ]Vu g ]?� d ] _ mih {3]zt eV�¿�l ] g ]�rn� hÂm�h � _ c \f{3]?\ h ]?\ mDmBcÃmBl�h \ ��c x mil ]?��] m�e§d ]?� c x mBl"g ]�r m �¶rV� h \"w�] d ]?\"w"]z\ m�c x c \�]­rn\ cVmBl ] g umBl ] e r g ] h \Fx r _ m g ]zt|r m ]?w h \F{Vr gihsc ["�¾�Nr e � � ( c �N]�{3] g u§� l r m h � �Zc � m�hs�Zd£cVg�m rn\ m¾h � mil r m�mil ] mBcVm rVt hÂm�ec x mBl"g ]�r m � � ["� m }�]­rnw"w g ]z�i��]?w } eªmil ]­� e � m ] �/g ]� P[ hsg ] � ]z\ m ��rV\"w�} e©mil ]�� e � m ] � r g _ l"hkm ] _ m [ g ]z�mBl r m&d"g ]z�i[ � ] mBc rVw"w g ]?��� mil"c �i] g ]� '[ hsg ] � ]?\ m � �

�)+( � �������¾�"� �"� �������R�� %

� � � � � � � � � � � ��� � � � � � � ��� ��� � � � � � � �(¯]?tk]?\µ°�]?tstk] g

� rVt h _ hsc ["�&r mim r _ � � _ rV\ m r � ] � rV\ e x c3gi� �?uR��[ �­� r g�h�� ]zw h \ � rV}"tk]F^ � ��r _?_ c3g w h \ jZmBc r _ tsrV�i� h ±��_ r mBhsc \�� _ l ] � ]�� l"c �&\ h \ ¡ hkj [ g ]#^ � �3uP}�rV�i]zw c \ ]?r g t h ] g � c3g��­c x � ]?[ � rV\�\ÃrV\"w � r gi� ] g ¹ ^V�V� Äv� ¡ c3g{ h ��[�rVt�� hk�­d t h _ hkm�e u mBl ]I± j [ g ] h ��r d"d�gic ¢ hs� r m ]zw­rn�Nr¶� hk�­d tk] mBg ]?] � ( c �N]�{3] g u hÂm r _ m [�rVtst e;g ] d"g ]?��]?\ m �rÃ� e � m ] �/c x5w"]z� _ g�hsd�mic3g � g r mBl ] g�mBl rV\�r m r¸¢ c \ c3�;e«h \ mBl ]�["��[�rVt���]?\"��]Vu h \ mBl r m r jVh {3]z\ �­h �i["��]� r e�h \f{ c tk{3] � [�t mBhkd ts] m ] _ l \ h '["]z��� hÂmBl"h \Ã�i]z{V] g rVt _ t|rV���i]z� �� l ] c3g w�] g¯c x _ r m ] jVc3gih�� r mihsc \Ãw"] d"h _ m ]zw h � gic [ j3l t e x gic3��mil ] d"lfe � h _ rVt)� c3g tsw mBc­mil ] l r g w§�½r g ]

mBc­mBl ]F� c x m �Nr g ]nu�rV\"w«x g�c3� ["\�rV[ mil"c3g�h�� ]zw©["�i] mic �Zh �i[��i] c x�rV[ mBl�c3gihÂm�e3� � l ]�± g � m _ tsrV�i� h \ _ tk["w"]z�]�¢ migih \�� h _ �Zh ��["�i]z� mBl r m _ rV\ m r � ] d t|r _ ]ª� hkmil"c [ m rV\ e r _?_ ]?��� mic mBl ] _ c3�­d [ m ] g � e � m ] �µ� � l ]�i] _ c \�w _ tsrV�i� _ c \ _ ] g \"�N� e � m ] � �Zh ��["�i]¯rV\�w m�ePd"h _ rVtst e�g ]� '[ hsg ]?��� c3� ] h \f{ c tÂ{3] � ]?\ m � hkmil _ c3�­d [ m ] gl r g w��Nr g ] c3g � c x m �½r g ] � � � cµm�e§d ]?� h \ mBl�h � _ tsrV�i�Dr g ]�]�r�{3]z�iw g�c3d"d"h \ j rV\"w h \ m ] g x®] g ]z\ _ ]«~ ["��[�rVtkt e]?tk] _ mBgic \ h _ c3g ]zts] _ mBg�c3� r j \"] mBh _ u'}"[ m½cVd�mBh _ rVt�rV\"w cVmBl ] g x cVgi� �Nr g ]�rVtk� c�d£c ��� h }"ts] ��� ��\ cVmBl ] gN� r ��c3gm�ePd ] c x mil"h � _ t|rn�i� h \f{ c tk{V]?�Iw"]z\ h rVt � c x|�¼�i] g { h _ ]�r m�m r _ � � mBl r m _ rV\Ã}�] _ cV�­�Zhkm�m ]?w g ] �ZcVm ]?t e � hÂmBl"c [ mrV\ e \"]?]zw x c3g rV[ mBl"c3g�h�� ]?wÃr _z_ ]z�i� � � l ] mil"hsg w _ tsrV�i� h \ _ ts["w�]?� � rV� P[�] g rnw h \ j;h \Ãr�{nr g�h ] m�e­c x�x c3gi� � �� l ]«x c [ g�milbh \ _ ts["w�]?� mil ]ª]z� m rn}"t h � l"� ]?\ m c x�w"]zx®] gig ]?w �­h �i["��]Vu½x c3g ]�¢�r �Zd ts]nu mBl ] _ g ]�r mihsc \ rn\"w

� *b�Q'B+B�W6:,) �?)<35%W��+B%��F)*�Q&*21' �*+B/1=V6�)�,- +B=/1,)�35/1%��K67�Q35) ,561�*�1�F21/1;�/1,Q V/�K,) ��)*21&*�R+B/$-435=+B% ,) %��:35/1%��5� :^��81&*�*��) (<# ����%Q2?)�+ �JI$8LI$,81&�%�21)*+ �JI%���)*��35+B/1' I.&�����-�&!%�,/1&*+B&*�*��/��! !+ ���GUV��'B��/��9��'B'B��) ] &bM�+B�� !�1��/G35�1�1'B+B��>A�*,a+B/?6�,)�-430�*+B,/4&���%�21)�+ �JINc

` �

Page 51: Practical Architectures for Survivable Systems and Networks (Phase

]?\"rV}"t h \ jyc xNr � gic�� rn\ l"cVg �i]�~ rV� c3d"d�c �i]zw mBc �i[�}"�i]� P[�]?\ m��Zh �i[��i] mBl r m r _?_ c3�­d rV\ h ]z� mBl ]Zr _ m [�rVt]�¢§] _ [ mihsc \ c x mBl ] � gic�� rn\§� l"cVg �i] d�gic3j3g r � � � l"h _ l � r e � l"c ��[ d h \ cVmBl ] g _ tsrV�i��]?��r m r©t|r m ] gmBhk� ] � u c3g�cnmBl ] g x cVgi� � c x d ]?� m;d�gic3j3g r � ��w h � _ ["���i]zw }£]zt c � � � l ]�±"x mBl _ tsrV�i� h \'{ c tk{V]?�D} e§d rV�i� c xrV[ mil"c3g�h�� r mBhsc \1u d£c �i� h }"t e ]z\�rV}"t h \ j r;["��] g5mic r d"d ]�r g�mic }£]#rV[ mil"c3gih�� ]zw � c3g \ cnmNmBc r d"d ]�r g r m rVtst~ mil r mNh �?u mBc }£] h \f{ h � h }"tk] mic;mBl ]�rV["w hkm�mBg r h ts� ��� � l ] g ] � r h \ h \ j _ t|rn�i�i]z� h \f{ c tk{V]�r _ mBh {V]�rV\�w d rV��� h {V]�Zh �i[��i] c x g ]?� c [ g _ ]?�?u h \�r _ mBhsc \ mil r m��­hkj3lfm¶g ]z�i["t m;h \ �Zh �i[��i]Vu rV\"w�±�\�rVtkt e©�Zh ��["�i] mBl r mDl ]?t d � h \_ r gig�ePh \ jFc [ m rVw"w hÂmBhkc \�rVt �Zh �i[��i]?��~ �i[ _ l rn� d"g ] d r g r mBhkc \­x c3g rV\yr m�m r _ �Zc \yrV\ cnmBl ] g � e � m ] � c3g ["��]c x¾r _ c3�Zd [ m ] g&h \µr _ g�hs�Zh \�rVt�]?\ m ] gid�gih ��] ���� l ] � r h \­w c �&\f�Nr g wÃ��t c3d�h \ j�gihsjVl'm � l rn\"w­w h r j3c \�rVtRt h \"] h \ ¡ hsj [ g ]�^ � � h \"w h _ r m ]?� m�ePd"h _ rVt£� m ] d �

rV\"w �­c w"]?� c x h \ m ]?\�w"]?w©["��] c x _ c3�Zd [ m ] g � e � m ] � � � � l ]�ts]zx m �Nr g wª} g rn\ _ l ]?��rVtst h \f{ c tk{V] �Zh �i[��i]Vu� l"h ts] mBl ] gihsjVl'm �Nr g w } g rn\ _ l ]?� g ] d"g ]?��]?\ mId�cVm ]z\ mih rVtkt e r _?_ ] d�m rn}"ts]�["�i] � ["\ mBh t�rDts]�x m �½r g w } g rV\ _ lh � m r � ]?\ � ~ � r _ l t|rn}£]zts]?w �Zc w"] c xI[��Br j ]­rVt c \ jymBl ] � r h \§��w h r j3c \�rVt h \ m ]?\�w"]?w§�¼["�Br j ]�t h \"] h � mBl ]rV\ mBhÂmBl ]z� h � c x mil ] _ cVgig ]z� d�c \"w h \ j ts]�x m �½r g w �Zh �i[��i]#} g rV\ _ l��À��� {3] g9e tk]zx m �Nr g wÃ} g rV\ _ lÃg ] d"g ]?�i]z\ m �¯r_ tsrV�i� c x1{P["tk\"] g rV} h t hkmih ]z� mBl r mN� [�� m }£]¯w"]zx®]z\"w"]zwyr j r h \"� m � mBl r m�h �?uP] hkmil ] g r�{ c3h w"]?w�rVt mic3j ] mBl ] g�cVg]?tk�i]�w"] m ] _ m ]zw4rn\"w g ] _ c {3] g ]?w�x gic3�µ� � l ] � ]?rV\"�#x cVg�d"g ]�{3]z\ mihsc \�u)w�] m ] gig ]?\ _ ]Vu)r�{ c3h w�rV\ _ ]Vu�w"] m ] _ �mBhkc \1u�rV\"w g ] _ c {3] g�eªm�ePd"h _ rVtkt e w h »£] g x gic3� c \"]�} g rV\ _ l©mBc mil ]�\"]�¢ m?� ~ � {V]?\ h \�r _ mBhkc \ � r e«hk�­d t e�Zh �i[��i]VuRrnt mBl�c [ j3l \ c rV}�["� h {3]�r _ m&c x _ c3�Z�Zh �i� hsc \ � r e l rT{V] c _?_ [ gig ]?w �¦�� l ] c3g w"] g�h \ j ["�i]zw h \ ¡ hkj [ g ]F^ � ��rV\"w � rV}"ts]�^ � � h � g�c [ j3l t e [ d � h w"]�w c �&\©x gic3� mBl ]F\�r m [ g rVt

t|r e ] gih \ j ["�i]zw h \ � rn}"ts]z�D� � �;rV\"wªW � � � ]�¢ _ ] d�m x c3gImil ] � ¢ mBg�h \"� h _ � h ��["�i] _ r m ] j3cVg�e u�� l"h _ l«h ��r mmBl ] mic3d1� � l�h � c3g w"] g�l ]zt d � micÃ� r h \ m r h \ mBl ]���]?\"��] c x mil ] _ [ � [�t|r mih {3]zt e�h \ _ g ]?rV� h \ j } h \"r g�e � mig ]z]_ l"c3h _ ]z� r m ]�r _ l tsr e ] g rV\�w mBl ]I��[ _?_ ]?�i�9x®["t _ l"c3h _ ]?� w c �&\ mBl ] gihsjVl'm ����t c3d"h \ j w h r j3c \�rVt c x ¡ hsj [ g ]I^ � � �q mD� ["� m }�]­\ cVm ]zw mBl r m \ c�m r¸¢ c \ c3�;e©h � d ] g x®] _ m�� � l ] g ]�r g ]­rVtk�Nr e �Dx®[ ���ze } c ["\"w�r gih ]z�;rn\"w

c {3] g t|r d � �4´ ]?� h w"]z�?u � rV\ e r _ m [�rVt d ] g�d ] mBg r mBhkc \"� h \'{ c tk{V] � ["t mBhsd ts] m�e§d ]?� c x �Zh ��["�i] �4�¯c _ t|r hs�h � � rVw"]�x c3g�mBl"h � d r g�mBh _ ["tsr g¶g ] d"g ]z�i]?\ m r mBhkc \ � ( c �5]z{3] g u mil ] _ r m ] j3c3gih ]?�D� l"c �&\ l ] g ] r g ]Z["�i]�x®["tvug ] _ [ g�gih \ j x g ]� '["]z\ m t eyh \ mBl ]¶w h � _ [��i� hkc \ mBl"g�c [ j3l"c [ mImBl"h � g ] d£c3g9m��� � c _ t|rV���i]z� c x �Zh ��["�i] m ] _ l \ h '["]?�5r g ] c x d"gihk� r g9e;h \ m ] g ]?� m l ] g ]Vu'\�r � ]?t e u3} ePd rV���i]?� c x�rV[ mil"c3g �

hkm�e ~ mig r d w cPc3g ]�¢ d t c3hkm r mBhkc \"�#rV\"w rV[ mBl�c3gih�� r mihsc \©r mim r _ � � � rV\"w d"g ] d t|rV\�\"]?w d ]?� mDd"g�c3j3g r � �#�i[ _ lrV� � gic�� rn\ l"cVg �i]z�?u � a { hsg ["�i]z�?u rV\"w©� c3gi� �?u�� hkmil ]z»£] _ m � h \ _ ts["w h \ j mBhk� ]�} cV� }"�?u�t c3j3h _ } cV� }"�?urV\"w j ]?\�] g rnt l rT{ c _ � ( c �N]�{3] g u���]z{V] g rnt cVmil ] g x c3gi� �¯r g ] hs�Zd�c3g�m rV\ m&h \ mBl ] d"g ]z�i]?\ m _ c \ m ]�¢ m u1rn\"wmBl ]?�i]�r g ]¶rVts� c w h � _ ["�i��]?w � �

�a��#$��# � !�O <"=�=?>P=� � !1O <�=?=�HKJ � HKJ�ST>PJ %�>�% 3E�J£STQ¸E�LK= � � g r d w cPc3g ��rV\"w cnmBl ] g � e � m ] � ³Rr��&� c x m ]z\ª]?\"rV}"ts] _ c \P�migic tk� mic }£]�} ePd rV���i]?w ��´5ePd rV��� h \ jµ� r e«h \f{ c tÂ{3] _ hkg _ [ � {3]z\ mBhsc \ c x ]�¢ h � mBh \ j _ c \ mBg�c ts�zu �­c w§�h ± _ r mBhsc \ c x mil"c ��] _ c \ mBg�c ts�zu cVgDhk�­d�gic3d ] g r _ '[ h � hkmihsc \ c x cVmil ] g � h �i]�w"]z\ h ]zw4rn[ mBl"cVgihkm�e u d"g ]����[ � rV}"t e � hkmil©mBl ] h \ m ]?\ m�mBc �i[�}"�i]� P[�]?\ m t e �Zh ��["�i] mil ]�r _ P[ hsg ]zw4r _?_ ]z�i� gihkj3lfm � �F´5ePd rV�i��]?w_ c \ mBg�c ts� �Zhsj3lfm�h \'{ c tk{V] cVd ] g r mih \ j �¼� e � m ] � rn[ mBl ]z\ mBh _ r mBhkc \ � ] _ l rV\ h � � �?u¸� e � m ] ��c3g w�r m rV}�rV��]r _?_ ]z�i� _ c \ mBgic ts�?u rV\"w ± g ]z�NrVtstk� � q�\ mil ] ¿ c3g tkw ¿�h w�] ¿ ]z}1u r m�m r _ � � � r e ]�¢ d t c3hÂm ³Rr��&� h \mil ] d"gicVj3g r �Z�Zh \ j ]z\f{ hkgic \ � ]z\ m�c3g�h \ } g�c �&�i] g �FrV\�w ��] g {V] g � � ¡ c3g ]�¢�r �Zd tk]Vu�� hkmil g ]?� d ] _ mmicFmBl ]�Y3r�{nr�t|rV\ j [�r j ]nu§�5]�r � \"]z�i�i]z� l r�{V]�}�]?]z\yx c ["\"w h \ mBl ]�t|rV\ j [�r j ]nu h \ mil ]�Y3r�{Vr �#hsg�m [�rVt

D _!�?�X67,'B'B,Q !+B/1=�>?�Q&*%�)�+B�?�*+B,/G+B&"35>:35������>A6�)�,-A>!�Q2?-435/1/G35/?> C`35)�;��) � � � � � K:35/?>A+B/��*21)�/.�WML,' ML�Q>A67)*,- &�,-��X�Q35)*'B+B�Q)F%�'H35&*&�+ O:%Q30�*+B,/1&>1+B&*%Q2?&�&���>^8�IG>V��21-435/1/ � � � � � # E /]� ���*�Q/?&�+ ML��>1+B&*%Q2?&�&�+B,/],56F�Q35%<��-�+B&�21&*��%�'H35&*& +B& �1)���&���/L����>^8�I >!��21-435/1/^35/1> C 35)*;��) � � � � � KT35'B,/1= !+ ���A� �135-��1'B��&",56R�Q35%<�@%�'H35&�&Q#`_!�?��IA35'B&*,a�1)���&*�Q/L�V35/@35/:35' I�&�+B&!,56R-�,)��V���:35/.�J F,���21/1>1)*�Q>A%Q35&���& � � � � � #

`�`

Page 52: Practical Architectures for Survivable Systems and Networks (Phase

UWO����8���4OgYG�S��� p Z MW�:���F� R�R � R O'r s �p �<� b ����]� U �������F����` ��Y/V:���c���8�S�:�N� � �������\���4V�_ R � d������] �c�txh�:��Y���_~MW�<� � � R ��������c���8�S�:�WuL�4Vf��� � �e`'��� R YG����� R Vf�]�sh��� � � �c����]Lkv�<�S`K��� R O^] Š� � ��

p ����,���t�����

UW��������� R �S��`g������,���P�����

UW��������� R �S��` R ���S�F�<�^�����

UjVX� � � � �����

x � ��_ ��R ��� R O8��O'Vf� R ���S�����iW��� �<���,�<�S� R ����`gVf� R YG���S� ��R Q

r � ���4VX�N�����

q � � � R � Y[Vf��� R O8����� ��R �4wUN�����<�S� R ����`g���8��_��� ��� �4Og�,���

����c���8�����W��`L�������n�����

����c���8�����W��`L������� ��V�Vf�4���

�S�F�<�S_��:�P� � ���������� M iW��� ���P� R � � OYG�S��� ��R ��VX� � � R

� k k � ������� �S������� � ��R Q��Y/�S���������SV:���

p k �p ���� � � �W� � ���������Y/�S���������SV:���

Ujk UjVX� � � �\� � ���,���V:� R ���S�����

s�� sh`K�,���S� ��R Q ��R ��� R O8�4OO��fYG�:�S�S��O�� � �������

pIp 8p �����P�����Q����<�F�IYG���

k�� kl���SdK���:����O ��R Q

�N| uL`8�������� � �������

� � ���������� � � ��� ��R � � V

� � Q����S� �8¦Å�� �������S���4����Y[��������8�����Wk � ������� �z�4V�_ R � dK�����

` �

Page 53: Practical Architectures for Survivable Systems and Networks (Phase

�/�<����� �8¦Å�� ��`L�,�4�P�<Y �����c���8�S�:�Nk � ���,������^9�%?06=�2403;y+5062�A/2�# q ���\w

��� � �����<�z���L` ��R Q � �������:� � ��� � � R �<Y b �:`8�����S� b �������N�SVf�S�:� R ��8 k � ���S�:�����4��� R ����� � � R�� ���8V � �<�^� R Q ��R �:��� ��R Q,]LO���Vf���8� � � R`�[p _L`8� � V��<�^��V�� � � R Q ��R Q � O8���c����������aoO ��� ��R Q�YG��P��� ��R ����8�

� "�2�9�#L+E+5062�A/24# q �N| w� �� �Q � V:�����SV:� � � R Q ��R Q � � � �<� ��R ��R QcO � �SV:���SO8�4O ��N�e�S����� R ���4O � ��8 �I� � ���SO8�S����� ��R Q � �:����Vf���S� R � V\���P����_����NO������ ��R �����SV:�:�8� � � R�� �oR ������YG����� R Vf� � �����4VX�S��� R � V\��P�<��_��:� {��<�c� ��R Q� [p _L`8� � V��<�^�����S��V b � R ]8��P���8O � �,V���� � � R �<Ye]���dK� � ���c� R �N���t�$��x������[p _L`8� � V��<�������c� � �����<Y ��dK� � ���c� R �W� R Oy���������<Q�j�c�4O � ����� ��������� O8� R � �<���t�<Y/���:� � � V:��x � �S_����8� R �:��O ��R QF��`8�e�S�:� �V:V:���S�

!�2�^A�#K%�!�B/03= � q k���wÅ���/� �c�$�:����� R ��� � � R�� Y3�<����� � O8� R � � �e` � � ���:� R ������� Vf��c���8�����N��`8�������c�Å�Å p � QQ�`L���V b���R Q��<������V b �t� R Vf����*� R � V:�<� � � R � ��R ����]�xh��� b �e����� � � R �Å �� p ���?`L���V b � R Oy���$�L�<� R Qc�<������V b �:]8�,�<��� � Vf�����<�S��` �ep ���,�L��� R QÅ#`� MW�f�exh��� b x��4� � ��R Q*���c�F��� b ��_L`8� � V��<�^xP_������4�<�$���8���t���t����8� ��R QÅ � rj� R�� �����t��Y ���:� � � V:�jx � ��_~���,�L�<YG�4O � O8� R � � �e`

�W#L2:9c-/%�&��,%�!�+52 q3p�p w�� ���f��� ��R QF��������$������� R � � � ���PYG���tYG������_����P� � �������Š�� ���S�<{�� R a>_���S���W�<���S�V b � q ��R Vf����O ��R QF���f���S�:�N�$���*����wŠ���� ��Q � Vj�,������ q ��YG���S�n�<Y[������{�� R _��������] ��R V:���,O ��R Q*� � �c� �$���*����wŠ� kv�<��� � ���� R �hxh���S�n�����S��V b ��]���V�d� � � ��R Q�O � ����� � ��������Oy�S����������Vf�4�Š�� � � �S���P�<���S�V b �:]8�����S�V�_ ��R Q*�S�F���S��Q����<�F�h� R O��S�:��� � V���� ��R Q

��"^- !�242�06=�� !�A�9�H/#L=�9�03;!89�06&,= &,%g!�A�9�H/&,%?0���!89403&$= q s � wŠ�� �����<��O8�L���P�����S��V b ��]KYG���� � R ` ��Y � � �<� � �:�e` �<Y �������Vf��� �

� � �c���S���$�:� � O8� R � � �,V���� � � R � R O'�<�8�S_�� R � � V:�<� � � R� [� �c���S���$�:� ��R � � � �<� ��� ��� � � R ���N�������8V:�<� � � RV [� �c���S���$�:�h�S�:�S� ��R �<� � � R ���PO8�4�<�����8V:�<� � � RO [� �c���S���$�:�P�S� R a>� � �c� � ��� � O���� � � R� Mj�<� ��R Q��,�?xN�:]�V:� R YG�,� � � R ��]�� R O���� � �������Y [� �c���S���$�:�P� R V:�<�,��������� � � R�� � � �$�����O � �c�����:�c� R ����� � � R O8�:�S� � �Q Uj��` R V�_��S� R �������,�?xN� � � Q ]L� � ���:a>��Y�a V�_���V b �S�*� � �c�:a>��Y�a>����� � R ��F�<� � �4�_ T �S_��:�P����Q � V\�:�S�S�����

� �� UW�8��_���� ��� ��� � � R �����S�V b ��]KYG���P� � ���c�����]8�����S��x���SO�Vf����V b ��R Q�]K��� b � R _��V b���R Q� ;<940��$#l+50324A/2�#y&,(W!�Az94H�&,%�0G9�" q Ujkvw q xP� � � ��R Q�]���� ��R Q�]8x � ��_~�<�����<�S� R �N�<�8�S_���� ��� ��� � � R w

�TŠ���S���<� � � R ]L�c�8O � �,V:�<� � � R ]��,���]������ � � Vf� O8� R�� ����� q ��R V:���,O8���tY3������� O�������� R ���S`�w� ��/�oR Vf�S�:�c� R �S���^��������V b � q � Q ]��S�<���<� � �<���S�V b �Sw��`� rj� R�� �����t��Y ���:� � � V:�j�S��dK� � � ��R Qc�<�8�S_���� ��� ��� � � R

�W!�242�0��,#l+10324A�24#�&$(N!�A�9�H/&,%?039�" q6p kvw q ���4��O ��R Q�]8x � ��_~�������<�S� R �P�<�8�S_���� ��� ��� � � R w� � sh�S��xN� ��R Q*�S� R O8���c��` ���P�������SV�_ ��R Q*YG���P������� � V:�����<�NV�_����S�VX����� � ��� � V:�� ��/�oR YG�:�S� R V:��� R Oy�<Q�Q����Q�<� � � Rvq �����,�4V � �<����` ��R O������<������4�Swf]L������� V�� R ����`8� � �� �� ��� � �:���tV�_,� R�R ���^� � ����� � �S�<� � � R � R O��<�S_��:�NO��<�S������� b ��Q��

� � 062�A/24#�94Hz%�&$A��$H 03=/!�;�9�03&$= qG� k}w � x � ����YG��� R �:Q���4VX��]8�����S�����h�<Y/��� � �S� � � R� ���� 2�#~!�2F!�= 03=/B�03%�#K;�9F!�03B ( &,%g2�A�7 2�#�^A/#K=�9F+5062�A/24# q3� Mjw � ���$a>� ��R ��������� R V:��`L�8� � � �

�F����V�_ ��R Q�]LY3��Vf���� ��R Q�������Q� R ���*�,���S��]��<�����8O � �<���:�P��V�� R�R���R Q

` �

Page 54: Practical Architectures for Survivable Systems and Networks (Phase

� r _ l"h \�] �­c w"]zt ~KY � � � u�rV\"w h \ mBl ]�Y3rT{nr�¨�]�{3]?t c3d"� ]?\ m ° hkm�� rnt mBl�c [ j3l � rV\ e­c x mBl"c �i]�{P["tÂ�\�] g rn} h t hkmBh ]?� l r�{V]F}£]z]?\ª±�¢§]zw c3g#g ]?w"[ _ ]?w ¹ �3����u)�3�T� Ä u£� c3� ];� mBh tst g ] � r h \ � o hs�Zh tsr gId"g�c }"ts] � �]�¢ h � m � hÂmBl"h \ mBl ] � h _ g�c � c x m q�\ m ] g \�] m�� ¢ d t c3g ] g ]?\f{ hsgic \ � ]z\ m u5rVt mil"c [ j3l mil ] d ]z\"] mig r mihsc \��m ]?\"w mBcZl r�{3] j3g ]?r m ] g�d�cVm ]z\ mBh rnt�w�r � r j3h \ j ]�»�] _ m � mBl rV\ h \ªY3¨�°�� � ^�~ � l"h _ l�l rV�&±�\"] g � jVg r h \r _?_ ]z�i� _ c \ mBg�c ts� � uP}£] _ rV["��] c x mil ]#tsr _ ��c x�rn\ ]?\�x cVg _ ]?rV}"tk]���] _ [ gihkm�e­d�c t h _ e�cVmil ] g�mBl rn\ � ] g ]zt ew hsj3hÂm rVtkt e � hkj \"]zw�r d"d ts] m � �aNcV�­�Zc \ _ rn�i]?� c x�[�\�rV[ mil"c3gih�� ]zw+r _z_ ]z�i� _ rV\ g ]?��["t m x g�c3� � e � m ] � rV\�w+["�ir j ]óRr��&�©~®] �·j"� umig r d w cPc3g � mBl r m¯d ] g��­hÂm w"]z{ hkc ["�¯r _?_ ]?��� d r mBl � � ��[ _ l rn� mil ]�x c tst c � h \ j ¹ ^n�'� Ä �

q�\�rVw�]� '[�r m ] h w"]?\ mih ± _ r mBhkc \1uPrV[ mil ]?\ mBh _ r mihsc \�u"rV\"wyrn[ mBl"cVgih�� r mBhkc \ c x�["�i] g �?u m rV� � �zu c3g � e ��m ] � � � ¡ r h t h \ j�mBc _ l ] _ �ªh w"]?\ mBhÂm�e rn\"wªx r h t h \ j�mBc�g ]� '[ hkg ]F\ c \"� d�cPc x rV}"tk]FrV[ mil ]?\ mih _ r mBhsc \r g ] _ c3�Z�­c \©� c [ g _ ]?� c x d"g�c }"ts] � � � o e � m ] � � d�cPc ±�\ j r m�m r _ � � � r e«g ]?��["t mDh \ª� l"h _ l r� e � m ] � _ c3�Zd£c \"]?\ m�� rV� '["] g rVw�]?�¶rV��rn\ cVmBl ] g?� � l ] %)>� �'� c3d�mihsc \ c x =?>PJ %'�4<�H L rn\"wmBl ] � Q�:�E�=zS¸= ±�tk]N]�¢ d t c3hkm ]?w�} e;mil ]½q�\ m ] g \"] m ¿4c3g�� ¹ Wf^n�§u3Wf����u3WV�3X Ä r g ]½]�¢"r �­d tk]?� � � l ]z�i]]�¢ d t c3hkm r mBhkc \"�¶rVtk� cyg ] d"g ]z�i]z\ m _ rV��]?� h \²� l"h _ l rV[ mBl ]?\ mBh _ r mihsc \�rV\"w4rV[ mil"c3gihÂm�e _ l ] _ �Ph \ j�5] g ]D} cVmBl rV}"��]?\ m�� ~ � rV�i�9� cVg w§� g ]?tsr m ]zw mig r d w cPc3g �&r g ]�\ cVm ]?wµ�i] d r g r m ]?t e }£]zt c � �¦�

q �Zd"gic3d ] g¶h \ hkmih rVt h�� r mBhsc \1� hs�Zd"gicVd ] g�h \ hÂmBh rnt w cV� r h \©�i]zts] _ mBhkc \ c3g �i] _ [ gihÂm�e²d r g r � ] m ] g � �hs�Zd"g�c3d ] g�d r g�mihkmihsc \ h \ j u�rV� h \ hk�­d t h _ hkm�cVg l"h w"w"]z\F� l r gih \ j#c x d�gih { h ts] j ]?w;w"r m r � ] � }�]?w"w�]?wc3d ] g r mBh \ j � e � m ] � d r g r � ] m ] g � h \ r d�d t h _ r mihsc \ � ] �­cVg�e � d r _ ] � q¼x mBl ] h \ hkmih rVt�� m r m ] h �\ cVm �i] _ [ g ]Vu mil ]?\�� l r m x c tst c �&� h � h \�w c ["} m�� o e � m ] � _ c \�± j [ g r mBhsc \1uR} cPcVm t c rVw1u h \ hkmih rVt �h�� r mBhkc \1u§rV\"wy� e � m ] � g ] h \ hkmih rVt h�� r mBhsc \Fx c tst c � h \ j;g ] _ c \�± j [ g r mihsc \yr g ]¶rVtst£�i] gihsc ["�½� c [ g _ ]?�c x5{§[�ts\"] g rV} h t hÂmBh ]z�?u�rnt mBl�c [ j3l²c x m ]?\ _ r g�gih ]zw c [ mDh \"w"] d ]z\"w"]z\ m;c x mil ]�� m rV\"w�r g w4� e � m ] �_ c \ migic tk� � � l ] =?>PJ %'�4<�H L %�>� � � c3d§mBhsc \F]�¢ d t c3hkm r mBhkc \ h � rVts� c r _ c \�± j [ g r mBhsc \ � rV\"r j ]��� ]?\ m�h \ hkmih rVt h�� r mBhsc \ d"g�c }"ts] � uR}�] _ rV["�i];� e � m ] � rnw �­h \ h � mBg r mBc3g � _ rV\ m [ g \ hkm¯c » � ~ � l ] em ]z\"w mBc ts]�r�{V] hÂm ]?\"rV}"ts]zwµx cVg½mBl ] hsgIc �&\ _ c \f{3]z\ h ]z\ _ ] �À�

q �Zd"gic3d ] g ±�\�rVt h�� r mBhsc \1� h \ _ c3�Zd ts] m ]?t e²l rV\"w�ts]?w rn} c3g9m �zu5r _?_ ]z�i� h }"tk]�{3]z� mBhkj ]?� c x&w�]�rVtkt c �_ r m ]?w g ]z� c [ g _ ]z��~ g ]?� h w"["]z� � u h \ _ c3�Zd tk] m ]�]�¢ m ] g \�rVt�w"]�{ h _ ]�w h � _ c \"\�] _ m �?u£rV\"w cVmBl ] g ]�¢ hkm �mBl r m w c \ cVm�d"gic3d ] g t e _ ts]?rV\Z[ d rnx m ] g mil ] � �i]ztk{3]z� � � d r g9mBh _ ["t|r g t e�h \�� h w hsc ["� ³Rr�� c x mBl"h �m�ePd ] l rV�N]�¢ h � m ]?w h \���]z{3] g rVt d£cVd ["t|r g5c3d ] g r mBh \ j � e � m ] � �¶~ h \ _ tk["w h \ j � � �#� � � u d ] g��­hÂm �mBh \ j r _?_ h w"]z\ m rVt d"hkj3jVe }�r _ �'h \ j ~ m r h t j r mih \ jf� � l ]z\©r�["�i] g�� � _ cV�­� [�\ h _ r mBhkc \Ãt h \"]��i[�»£] g �rV\ h \ m ] g�g [ d�mihsc \ ��mBl ]�\�]�¢ m ["�i] g � l"cyl r d"d ]?\�� mBc }�]�rV�i� hsj \�]?w mBl ]��Br � ]Ft cVj3h \ d£c3g9m�h �r m�m r _ l ]zw mic�mBl ]&� mih tktÂ�r _ mBh {3]5["�i] g ��c } � � l"h � m�e§d ] c x d�gic }"tk] � _ c \ mBh \'["]?� mBc¶g ] _ [ g�h \�\"]z�� e � m ] � ��~KrVt mBl"c [ j3l � c3� ] mBhk� ]z�½rV�½r _ c \�± j [ g r mBhsc \ c3g _ rV}"t h \ jFd�gic }"tk] �*g r mBl ] gNmBl rn\yrV\h \ _ c3�Zd ts] m ] m ] g��­h \�r mBhkc \ ���

q�\ _ c3�­d ts] m ] cVg h \ _ c \�� h � m ]z\ m¾g ["\P� mBhk� ]�{nrVt h w�r mihsc \�� hs�Zd"g�c3d ] g r gij [ � ]z\ m {nrVt h w�r mihsc \1u m�ePd ]_ l ] _ �Ph \ j u�rn\"w�} c [�\"w"� _ l ] _ � � � x r h ts[ g ] mBc d"g ]z{V]?\ mµd ] gi�Zh �i� hsc \��?u P[ cVm rV�zu�rV\�w cnmBl ] gd"g�c3j3g r �­� ]?wbt hs�Zhkm ��x g�c3� }£] h \ j ]�¢ _ ]?]zw"]?w � _ c \ migic t�} e§d rV�i� c3g �Zh � d t|r _ ] � ]?\ m?��º \�]]�¢�r �Zd tk] h � mBl ] �Zh �i� h \ j } c ["\"w�� _ l ] _ � h \ ��>fS¸= u)� l"h _ l �NrV�D]�¢ d t cVhkm ]zw } e©mil ] �¾J ��>'Qr m�m r _ � [��i]?w h \ mil ]�q�\ m ] g \"] mD¿4cVgi� � ]z\�rV}"t h \ j mil ]�]�¢§] _ [ mBhkc \ c x½r g } hÂmBg r g�e _ c w"] c \mBl ] c {3] g ³ c �5]?w²� m r _ � }�[�»�] g?� q�\"� m rV\ _ ]?� c x�}�[�»�] g#c {3] g ³ c �&�¶r g ]D{V] g9e x g ]� '["]?\ m r �­c \ jmBl ]�r g _ l"h {3]?� c x }"[ j _ c tkts] _ mBcVg � � ~ ¡ c3g ]�¢�r �Zd tk]Vu"��]?] mBl ] ´ ¬ � � p&� � \"]��&� j3g�c [ d1�¦�

q �Zd"gic3d ] g \"r �­h \ j ��rnt h rn�i]?�Z~®] �·j"� u � ["t mihsd tk]F\�r � ]?��� hÂmBl�h \ _ c \"� h � m ]?\ m ]z»£] _ m � � u ��]�r g _ l �d r mil rV\ cV� rVt h ]z�?u�rV\"w cnmBl ] g _ c \ m ]�¢ m ��w"] d ]z\"w"]?\ m ]z»£] _ m �&~®�Br � ]�\�r � ]VuV}�[ m � hÂmBl w h »£] g ]z\ m

` �

Page 55: Practical Architectures for Survivable Systems and Networks (Phase

]z»£] _ m �zu�w�] d ]?\"w h \ j [ d£c \ mil ]¶w hsg ] _ mic3gih ]?�zu c3d ] g r mBh \ j � e � m ] � {3] g � hkc \1uRrV\�wµ� c­c \ ����

q�\�rVw�]� '[�r m ]D]z\ _ r d �i["tsr mBhkc \1� tsr _ ��c x h \�x c3g�� r mihsc \ l"h w h \ j u�r _z_ ]z�i� h } h t hkm�e­c x h \ m ] g \�rnt�w�r m r� mig [ _ m [ g ]?�zu�rVt m ] g rV}"ts]�rV["w hkm&mBg r h tk�?u �­h w§� d�gic _ ]?��� _ c \ mBg�c t mig rV\���x®] g �?u l�h w"w"]z\ c3g ["\"w c _ [P�� ]?\ m ]zw�� h w"]¶]z»£] _ m � �

º#mBl ] g �i]� '["]?\ _ h \ j�d"g�c }"tk] � �?� h \ _ c3�Zd tk] m ]#r mBcV�­h _ hkm�eFc3g �i]� '["]?\ mBh rVt h�� r mihsc \�u§rn� h \�x rn["t m�el rV\�w"t h \ j�c x h \ m ] gig [ d�m � c3g ] gig�c3g � � ³Rr��5]?wµrV� e \ _ l�gic \ c ["�Nx®["\ _ mBhkc \�rVt hkm�e u'��[ _ l rV� d ] g��­hÂm �mBh \ j ["\"w"]z� hkg ]?w _ l rV\ j ]?� mic }�] � rnw"]¶}£] m �N]z]?\ mil ] mBhs� ] c x {Vrnt h w"r mBhkc \ÃrV\"w mBl ] mihs� ] c x["��] �"h \ _ c3g�g ] _ m ��] gih rVt h�� r mihsc \�u g ]z�i["t mBh \ jFh \ l r gi� x®["t�\ c \"w�] m ] gi�Zh \ h � mih _ }£] l r�{ hsc3g u��i[ _ l rn�_ g�hkmih _ rnt g r _ ] _ c \"w hÂmBhsc \"� � rV\"w cnmBl ] g rV� e \ _ l"gic \ c ["�½� h w"]¯]z»£] _ m � � � l ]#� c � _ rVtstk]?w mBhs� ]�� c x|�_ l ] _ �Zmic�mBhk� ]�� c x|�¼["�i]D~ � cfa5m � c ¬ ��d"gic }"ts] � h tstk["� mig r m ]?��} cVmBl­h \�rnw"]� '[�r m ]#r mBc3�Zh _ hkm�e rn\"wh \"rVw"]� '[�r m ]¶]?\ _ r d ��["t|r mihsc \��5rn\�]�¢"r �­d tk] h � mBl ]D� hkm [�r mBhkc \ h \Ã� l"h _ l u�rnx m ] g {Vrnt h w"r mBhkc \ h �d ] g x cVgi� ]?w c \ mBl ];r gij [ � ]z\ m � c x�r _ rVtkt)} e�g ]�x®] g ]z\ _ ]nu mBl ] _ rVtkts] g _ rV\ mBl ]?\ _ l rV\ j ] mBl ]r g�j [ � ]?\ m � � �#ts� c u�� d�cPc ±�\ j r m�m r _ � �DrV\"w g ] d t|r e r mim r _ � � _ rV\ g ]?��["t m x g�c3� d"g ]?w h _ m rV}"ts]c3g�m r �­d ] g rV}"ts]&��]� '["]?\ _ h \ j � ] �·j"� u ¹ ^3^n� Ä � c3g \ c \ � r m _ l"h \ j �i]� '["]z\ _ ]zw c3d ] g r mihsc \�� �rV� h \�o � � r mim r _ � � �

º#mBl ] g t c3j3h _ ] g�gic3g �?�)x c3g ]�¢�r �Zd ts]nu h \f{3] g�m ]zw­t c3j3h _ u _ c \"w hÂmBhsc \"� c3g�c [ m _ c3� ]?� \ cnm d"gic3d ] g t e� r m _ l ]zwµ� hÂmBl } g rV\ _ l ]z�?uR� h tsw _ c \ mBg�c t mBg rV\"��x®] g ��~ ]z� d ] _ h rVtkt e h x)["\"w c _ [ � ]?\ m ]?w ���

� r h t j r mih \ j�� r eyc _z_ [ g r _?_ h w"]z\ m rVtkt e � l ]z\²r­["��] g�h � g rV\"w c3� t e r m�m r _ l ]zw mBc rV\ hk�­d"g�c3d ] g t ew�]�r _ mBh {nr m ]?w g ]?� c [ g _ ]Vu��i[ _ l rV�&r d�c3g9m½mBl"g�c [ j3l � l�h _ l r d"gic _ ]z�i� h �N� mBh tst�t c3jVj ]?w h \yrVt mil"c [ jVlhÂm � c3g�hsj3h \�rVt¾[��i] gDh �¶\ c t c \ j ] g r m�m r _ l ]zw � ¬¯\ h \ m ]z\"w"]zw r _?_ ]?��� � r e rVts� c�g ]?�i[�t m x gic3�/cnmBl ] gmig r d w cPc3g r m�m r _ � �?u)t cVj3h _ rVt � _ r�{3]?\ j3h \ j ~ ] �Áj"� u g ]�rnw h \ j ry� _ g r m _ l4m r d ]�}£]�x c3g ]�� g�hkmBh \ j [ d�c \hÂm�� u£rn\"w²rV� e \ _ l�gic \ c ["�¶r mim r _ � ��~ ] �Áj�� u h \ _ c3�­d ts] m ];r mBc3�Zh _ mBg rV\"�ir _ mihsc \"�zu1rV\�wªw h � _ g ] d rV\ _ h ]z�}�] m �5]?]z\ mBhs� ] c x _ l ] _ � rn\"w mBhk� ] c x�["��] ��� ¡ c3g ]�¢�r �Zd ts]nu mBg r d w c§cVg � h \ mBl ] hs�Zd ts] � ]z\ m r mihsc \c x¾]z\ _ g9e§d§mBhsc \ _ rV\ d ] g��­hÂm ["\�rn\ mih _ hsd r m ]?wµr _z_ ]?��� mic ["\"]?\ _ g�ePd�m ]?w h \�x c3g�� r mihsc \ �� rV�i�9� cVg w r mim r _ � �yr g ]©r d r g�mih _ [�t|r g t e h \�� h w hsc ["�­�i["} _ tsrV�i� c x mig r d w cPc3g r mim r _ � �yrn\"w � r eh \f{ c tÂ{3]Vu"x cVg ]�¢�r �Zd ts]

� ["]?��� h \ j�c x d rn�i��� c3g w"�?u½}"rV�i]zw c \ _ c3�­�Zc \ � mBgih \ j �µ~®�i[ _ l rV��w h _ mBhkc \�r g9e � c3g w��­rn\"wd"g�c3d ] g \�r � ]?� �5c3g � mBg�h \ j � mBl r m½�­hkj3lfmNl r�{V]�� c3� ]�t cVj3h _ rVt�rV�i� c _ h r mihsc \�� hÂmBl rn\ h \"w h { h w§�[�rVt¾["\"w"] g r mim r _ � ~ ��[ _ l rn� h \ hÂmBh rnts�?u�� d�c ["��] � �¶\�r � ]Vu�w c3j � ��\�r � ]nu�rV\"w²� c _ h rVt¾��] _ [ gihkm�e\'[ � }�] gB���

a r d�m [ g ] c x§["\"]z\ _ g9e§d§m ]?w d rV�i�9� cVg w"� h \ mBg rV\"� hkm ~®{ h r&t c _ rVt c3g�j t c }�rntV\"] m u cVg } e�mig r d w cPc3g ��i[ _ l rV�¯["� h \ j ¥�w"]z{�¥ � ] � x cVg¯g ]�rVw h \ j�mBl ]¶]z\ mihsg ];¬¯\ h ¢ � ] �Zc3g9e"� u"� l ] mil ] g¯c3g \ cVm¯mBl ]d rV����� c3g wµ±�ts] h �&� mBcVg ]?w h \y]z\ _ g9e§d§m ]?wµx c3gi�µ�

¨�] g�h {nr mihsc \ c x d rV�i�9� cVg w"�&} e rVt j3c3g�hkmBl��­h _ � ]�rn\"� � � r g�hsc [�� m ] _ l \ h P[�]?�¯r g ]�{nrV� m t e��Zc3g ]]z»£] _ mBh {3] mil rV\�]�¢ l rV["� mBh {3]«]z\'[ � ] g r mihsc \ � ¡ c3g ]�¢�r �Zd ts]nu h x d rn�i��� c3g w"�Ãr g ] � \ c �&\ micl r�{3]Zr d r g�mBh _ ["tsr g x c3gi� ~ }�] _ rV["�i] mil ] e r g ]�rVt j3c3g�hkmBl��­h _ rVtkt e­j ]?\"] g r m ]?w1u1x cVg ]�¢�r �Zd tk] � umBl r m rVt j3c3gihÂmBl"� _ rV\©}£]�[��i]?w mic r mim r _ ��mil ] �µ� � rV�i�9� cVg w"� _ rV\©� c3� ] mBhk� ]z��}�]Fw"] g�h {V]?w} eÃh \§x®] g ]z\ _ ]nuRrV� h \ mil ] � ����� � 3E�J)J)>�VS ³Rr�� [�� h \ j r � r m _ l �rV\"wP��� l�h x m r d�d"gic r _ lymic

� E )<35%��9%�,/1>1+ �*+B,/G+B&"3 &�+ �*2:30��+B,/.+B/4 V�?+B%<�����1� ,2���%�,-��9+B&F>1���Y��/1>1��/L�X21�Y,/A+B/��*��)�/:35'Y��+B-�+B/?=�%�,/1&*+B>1��)<30�*+B,/1&�# E )<35%��9%�,/1>1+ �*+B,/G+B&���� ��

�� ?+ 6 &�,-��W���?+B/1=a��'B&�� >1���Y��/1>1+B/1=�2?�N,/.���130�X,2?�*%�,-�� -43QI48Y�$3��N��%��*��>P8�I.+ �*&"/1,/1>1�W�*�Q)*-�+B/1+B&�-@K?35/1>A+B&%� ���

����"��

�� �,5���1��)� V+B&*�#

` �

Page 56: Practical Architectures for Survivable Systems and Networks (Phase

w"] m ] _ m�d r j ]Dx rn["t m r _ mBh { hÂm�eÃc \ mBl ]D\"]�¢ m �i] gih rntst e _ l ] _ � ]?w d rV����� c3g w _ l r g r _ m ] g?� ¨ h _ mBhkc �\�r g9e r m�m r _ � � r g ] d r g9mBh _ ["tsr g t e�d�c3d [�t|r g)mBl ]z�i]Iw�r e �?uf� l ] g ]?} e ]?r _ l ]?\ mBg9eFh \�r d r g�mih _ [�t|r gc \§�¼t h \"]5w h _ mihsc \"r g�e¶h � ]?\ _ g�ePd�m ]?w1uPrV\"wFr � r m _ l � c [ j3lfm � hkmil;mBl ] _ c3g�g ]z� d�c \"w h \ j ]?\ mBg9eFh \mBl ]�]z\ _ g9e§d§m ]?w d rV����� c3g w«±"ts] � o§[ _ l«d"g ]?]?\ _ g�ePd�mih {V];w h _ mBhkc \�r g9e r m�m r _ � �&�N] g ]Dw"]?� _ g�h }�]?w} eZ´Nc } � c3g�gih ��rV\�w�°�]?\ � l"c3�Zd � c \ ¹ ^3^VW Ä rV\"w��5] g ]¯]�¢ d t c3hkm ]?w h \ mBl ]¯q�\ m ] g \�] mN¿ c3g����¬���] c x x c3g ] hkj \§�¼� c3g wÃw h _ mBhsc \�r gih ]?� h �&rVts� c _ c3�Z�­c \ �

� ¢ h � m ]?\ _ ] c x�["\ h \ m ]z\ mihsc \"rVt�["\ h {V] g �BrVt d rV�i�9� cVg w"�zu1� hk�­h t|r gNmic � � ]?tk] mBc \ � ] e � mil r m#c3d ]z\rµ� h w"] g rV\ j ] c xIt c _ � � � q�\4r m ts]�rn� m�c \"] _ rV�i]nu hkm �NrV� d�c �i� h }"tk] mBc«j ]?\"] g r m ]­� c ["tswP��}�]d rV����� c3g w����ir mBh ��x ePh \ j rVtstPt c3jVh \ g�c [ mih \"]z�¾x c3g r jVh {3]z\�� e � m ] � ]�{3]?\�� hkmil"c [ m¾� \ c �&ts]?w j ] c xr�{Vrnt h w d rn�i��� c3g w � q�\ mil r m _ rV��]Vu£r �Zh ��� h \ j } c [�\"w"� _ l ] _ �µd ] gi�Zhkm�m ]?w�rV\ h \ m ]z\ mBhsc \�rVtst ec {3] g t e t c \ j²d rV����� c3g w _ c \"� h � mBh \ j�c x�r g rV\"w c3� �i]� '["]?\ _ ]«x c tkt c �N]zw } e hÂm ��]?\ _ g�ePd�m ]?wx c3g��*mic;c {3] g � g�hkm ] mBl ]�� mBc3g ]?w ]z\ _ g9ePd�m ]zw d rV�i�9� c3g wyrV\"wÃw"]�x®]�r m5mBl ] d rV����� c3g w _ l ] _ �Ph \ jd"g�c3j3g r � ¹ W3�f^ Ä|���

� ¢ h � m ]?\ _ ] c x mBg r d w c§cVg � mBl r m g ]� '[ hkg ]¯\ c¶d rV����� c3g w"�Nr m rVtstKufrV� h \ mil ] g ] �ZcVm ]It c3j3h \Fx gic3�r¶� hs�Zh tsr g t e \�r � ]?w�}"[ m } c3j ["��x c3g ] hkj \�["�i] g ~®] �·j"� uP[�� h \ j¶mil ]¯¬�\ h ¢ � Q�:)E�=zS x r _ h t hÂm�e���� � l ]d"l"h t c � c3d"lfe�c x�r«� h \ j tk]­["\ h {3] g �irVt½t cVj3h \ rV[ mil ]?\ mBh _ r mihsc \ x c3g r d r g�mih _ [�t|r g ["�i] g;mBl r mFh �{nrVt h w mBl"g�c [ j3l�c [ m rVtkt d r g9m � c x�r�w h � mBg�h }"[ m ]?w�� e � m ] � rn\"w�� � c3g �i] e ] m � mBl"g�c [ j3l"c [ m r\"] m � c3g���c x�\"] m � c3g�� � g ] d"g ]z�i]z\ m �Nrn\Z]z\ c3g��­c [��¾{P["ts\"] g rV} h t hÂm�e un}£] _ rV["��] c \"] _ cV�­d"g�c3�Zh �i]rV\ e � l ] g ] _ rV\ g ]?��["t m&h \µ]�¢ m ]?\�� h {V]�w"r � r j ] mBl"g�c [ j3l�c [ m��

q�\ m ] gig [ d�mBh \ j w"[ g�h \ j rn[ mBl ]z\ mBh _ r mBhkc \©~®] �·j"� u"t c3jVj3h \ jDh \­� hkmBl rV\ h \ _ c3g�g ] _ mId rV����� c3g w�u h \§�m ] gig [ d�mBh \ j u£rV\"wªw h � _ c {3] g�h \ j�c \"]?��]?tÂx ]z»£] _ mih {V]?t e rV[ mBl ]z\ mih _ r m ]zw � � l"h _ lªg ]z�i["t m �¯x gic3�h \"rVw"]� '[�r m ]�r mBc3�Zh _ hkm�e���� � l"h �&�NrV�#r d"gic }"ts] � c \���]z{V] g rnt¾]�r g t e l"hsj3l ] g �¼t|r e ] g rn[ mBl ]z\ mBh �_ r mBc3g �;~ mBl r m&h �?u�\ cVm¯h \ mBl ] cVd ] g r mih \ j � e � m ] � ���

� w hkmih \ j rn\ h \�rVw�]� '[�r m ]?t e«d"gicnm ] _ m ]zw d rn�i��� c3g w�±�tk] mBcÃh \"�i] g�m r } c3j ["��}"[ m { h rV}"tk]F["�i] gh w�]?\ mBh ±�] g rV\"w d rn�i��� c3g w ~ hs�Zd"gicVd ] g ]z\ _ r d �i["tsr mBhkc \1u&rV[ mBl ]z\ mih _ r mBhkc \1uIrV\�w rV[ mil"c3gih�� r��mBhkc \ ���

q�\"��] g�mih \ j r mig r d w cPc3g&h \ mBc rV\ªrV[ mBl"c3g�h�� r mBhkc \ d"gic3jVg r � � hÂmBl"h \ mil ]���] _ [ gihÂm�e«d ] g�hs� ] m ] g?�� l ] _ t|rn�i� h _ rVtR]�¢"r �­d tk] h � mBl ] a � _ cV�­d"h ts] g � g�c�� rV\ l�c3g ��]#w"]z� _ g�h }�]?w } e � l"c3�Zd � c \ ¹ Wf 3^ ÄrV\"wµw h � _ [��i�i]zw h \«oP] _ mihsc \²� � W �

� l ]«{nr gih r mBhkc \"��� hkmBl�h \ mil"h � _ t|rV���Ãr g ]ªr � r �?h \ j t e gih _ l�� � l ] g ]²r g ]©rnts� c _ c3�Zd r g rV}"ts]«r m �m r _ �«m ] _ l \ h '["]?�¶x c3g�mBl ] �Zc3g ]F� c3d�l"h � mBh _ r m ]zw4rn[ mBl ]z\ mBh _ r mBhkc \©� _ l ] � ]?�?u �i[ _ l rV� _ l rVtkts]z\ j ]��g ]?� d£c \��i]�� _ l ] � ]?�?u mic3� ]z\ rn[ mBl ]z\ mBh _ r mBcVg �?u1rV\"w cVmil ] g rn[ mBl ]z\ mBh _ r mBcVg ��}�rV��]?w c \ d [�}"t h _ � � ] e]z\ _ g9ePd�mBhkc \ ��� {V]?\ h x c \"]�� mBhk� ] mic3� ]z\©rV[ mil ]?\ mBh _ r mic3g �#r g ]�["�i]zwªx c3g rV[ mBl ]?\ mBh _ r mihsc \«r m r g ]���ZcVm ]­rn[ mBl ]z\ mBh _ r mBhkc \��i] g {3] g u mBl ] d"g ]?��]?\ _ ] c x � [�t mBhkd ts]�w�] _ ]z\ mBg rnt h�� ]?w ��] g {3] g � _ rn\ d ] gi�Zhkmd t|r e }�r _ ��c x�r _ r d�m [ g ]zwyrV[ mil ]?\ mBh _ r mic3g � hkmBl�h \ mil ] mihs� ]I� h \"w c � ~ m�e§d�h _ rntst eFc \ mBl ] c3g w"] g�c xmil"g ]z]�W3X��¼�i] _ c \"w h \ m ] g {nrVts� � u g ]?��["t mih \ j­h \©rnt �Zc � m�h \"� m rV\ m rV\"] c ["� d ]?\"] mBg r mBhsc \"��r m�mBl ] � � �����] g {3] g � � � g ]?w h _ m rV}"tk]�}£] l r�{ hsc3g½c x � ]?���Br j ] l rV� l�h \ j �NrV�I["��]?w mBc } g ]�r ��� ] m � _ r d ] � � _ g�ePd�mBc �jVg r d"l�h _ rntst e }�rn�i]?w��i] _ [ g�hkm�e3� q�\«rnw"w hkmihsc \�u"¨ g ]�� ¨�]�rn\ l rV� g ] _ ]?\ m t e x c ["\"wµ� c3� ] h \ migihsj [ h \ jmil ] cVg ] mih _ rVt��N]?r � \"]?���i]?� h \Z�N]ztst � � \ c �&\ l rV� l"h \ j rVt j3c3gihÂmBl"� ��~ � ¨���u � ¨¶�Pu"o (¯�¯�B� � [��i]?w x cVgrn[ mBl ]z\ mBh _ r mBhkc \yrV\"w h \ m ] j3g�hkm�e _ l ] _ � � ¹ �f  ÄK�

` �

Page 57: Practical Architectures for Survivable Systems and Networks (Phase

�a��#$� � 8�>P=zSZ8�Q¸E �RQ�<�� =� 8#>§=�S�O Q¸E �RQ¸< � =#<�J'% =?>fS�STHKJ � �)O4= � �¾=?>�����>PJ£S)� H = � =z>§= � � ]z� m�d"g�c3j3g r � r m�m r _ � � h \f{ c tk{V]mil ] _ g ]?r mBhkc \1u d t|rV\ mih \ j uPrV\�wÃr gi�Zh \ j�c x�� c x m �Nr g ]�} e ["� h \ jF� ] mil"c w��N�i[ _ l rV� � gic�� rn\ l"c3g ��]?�zut c3j3h _ } c3� }"�zu mBhs� ]�} c3� }"�zu"ts] mim ] g } cV� }"�?u � rVt h _ hsc ["��� cVgi� �?uRrV\"wÃ{ hsg ["�i]z� �� � g�c�� rV\ l"c3g �i] h � m�ePd"h _ rVtst e r _ c3�Zd [ m ] g½d"g�c3j3g r � mil r m ��[ gig ] d�mihkmBhkc ["��t e _ c \ m r h \"�Nx®[�\ _ mihsc \§�rnt hkm�e�mBl r m _ c \ m r h \"�#r l"h w"w"]?\«� c [ g _ ] c x gih � � u£� hkmil ]z»£] _ m � c x�{Vr g�ePh \ j �i] gihsc ["�i\"]z�i� � � t cVj3h _} c3� } h ��r � gic � rV\ l"cVg �i]Z� l"c ��] ]z»£] _ m ��r g ] migihkj3j ] g ]?w�} e mil ] c _?_ [ gig ]?\ _ ] c xI� c3� ]­t c3j3h _ rVt]�{3]z\ m?� � mBhk� ]&} c3� } h �Nr�t c3j3h _ } c3� }­� l"c ��]�t cVj3h _ rVt mBg�hsj3j ] g5h �5}"rV�i]zw c \ mBhk� ] � � { hkg ["� h �5rd�gic3j3g r � mil r m _ rV\ hÂm ] g r mih {3]zt e�h \�x®] _ m&cVmil ] g&d"g�c3j3g r � �N� hÂmBl _ c3d�h ]?� c x hkm �i]ztkx � � ] g � c \�rVt _ c3� �d [ m ] g { hkg ["��]?� m ]?\�w mBcZd"g�c3d r j r m ]¶rV��r g ]?��["t m¯c x � rn\P["rVt�r _ mihsc \��¯��[ _ l rn�¯� l r g ]?w«w h � � ] m�m ]?� �� r h \�x g r � ]�{ hkg ["��]?� h \ mil ] cVg�e _ c ["tsw d"gicVd r j r m ]DrV[ mBcV� r mih _ rVtst e uP}"[ m r g ] g r g ] � � � c3g�� h �¯rd�gic3j3g r � _ r d rV}�ts] c x ]�¢§] _ [ mBh \ jZd"h ] _ ]?� c x hkm �i]ztkx)� hk� ["t m rV\"] c ["�it e u c x m ]?\ g ] �ZcVm ]zt e3� � l ]?�i]�r g ]w h � _ ["�i��]?wµx®[ g�mil ] g }�]?t c � ���\ ePmil"h \ jDmil r m r d"d ]�r g � h \"\ c _ ]z\ m t e rn��w"r m r¶}"[ m � l"c ��]#]�¢�] _ [ mihsc \ _ rV\Z}�] migihsjVj ] g ]?w��i[ g�g ] d �mihkmihsc ["��t e�g ] d"g ]?��]?\ m �¯r;��] gihkc ["� g�h � ��� ¿ ]z}Ã} gic �5] g � d�g ]?��]?\ m \'[ � ] gic ["� c3d"d�c3g9m ["\ hÂmBh ]?�5x cVg5mBl ]]�¢§] _ [ mBhsc \ c x � g�c�� rV\ l"c3g �i]?� c \ e3c [ g¯c �&\ � r _ l�h \"]�� l ]z\ e3c [ g } gic �&�i] g w c �&\"t c rVw"�¯rV\�r d �d ts] m u3}�] _ rn["�i] mil ]&r d"d tk] m m�ePd"h _ rVtkt e ]�¢§] _ [ m ]?��� hkmil rVtst c3g � rV\ e;c x eVc [ g ]�¢�] _ [ mihsc \ d"g�h { h tk] j ]z� �� l�h � h � r d"g�c }"ts] � � hkmil Y3r�{nr�r d"d tk] m �?uV� _ mih {3] � _ c3�­d�c \"]z\ m �?u3rV\"w;} gic �&�i] g d ts[ j � h \"� � � c } h ts]_ c w�] _ rn\ _ rV["��]I� c3� ] d r g�mih _ [�t|r g t e \�rV� m�e ��] _ [ gihÂm�eFd"g�c }"ts] � �zuV]z� d ] _ h rVtst e¶h x hÂm¾c3g�hsj3h \�r m ]?��x gic3�rn\�["\ mBg ["� m � c3g9mBlfe � hkm ]�� � l ] g ]�rV\ e�¿ ]?} } g�c �&�i] g5� r e r _z_ ]z�i�IrD� hkm ] mil r m5l"c ["��]?�Nr�� m rV}"tk]x®[�tst c x � gic � rV\ l"c3g ��]?� c3g�d ] g��­hÂm�cVmil ] g�m�ePd ]z� c x h \ mBg ["� hkc \"� ¹ �TX3W§u¾�T�3X�u�W3^V� Ä u�["\'}£] � \ c �&\"� mmic [��i] g � � ~ ¡ c3g rV\ h \ _ h � h {V]�r _z_ c [�\ m�c x �Zc } h ts]�� _ c w"]F��] _ [ gihÂm�e u ��]?] � r g9e � _ ��g r�� rV\�w � w¡ ]zt m ]z\ � ��Y3r�{nr«�i] _ [ g�hkm�e } cPc3� ¹ ^VXVX ÄNcVg;d"g ]zx®] g rV}"t e4hÂm �;��] _ c \"w ]?w hÂmBhkc \ ¹ ^VX�� Äv�¦� � rV\ e cnmBl ] g� hkm [�r mBhkc \"� l r�{3] � hs�Zh tsr g�gih � � � �«¿ c3g w � r _ gic { hsg ["�i]z��rV\"w mBl ] d�g ]?��]?\ _ ] c x¯rV\ ]�¢§] _ [ m rV}"tk]d�gih \ mih \ j �¼t|rV\ j [�r j ] h \ m ] g�d"g ] m ] g ~ ] �Áj�� u�x c3g � c � m o _ g�hsd�m �¯c »£] g x®[ g�mil ] g�c3d"d�c3g�m ["\ hÂmBh ]z�¯x cVg _ c3� �d�gic3�Zh ��]Nx gic3� c [ m � h w�] mBl r m _ rV\Z�i] m [ d _ c3�­d�gic3�Zh ��]Nx gic3� � hkmil"h \ mil r m�g ]z�i["t m x gic3� r � gic � rV\l�c3g ��] mBl r m � c ["tsw©��]?] � mBc }£] cVg w h \�r g�e w�r m r � o hs�Zh t|r gIc3d"d�c3g�m ["\ hkmih ]z��r g�h �i] h \ a ¨���p º � �?u�zhsd w gih {V]?�zu�rV\"w cVmil ] g�d�c3g9m rV}"tk]�� mBc3g r j ] � ]?w h r�u�r j ]?\ m � c x m �Nr g ]nu�� _ g�hsd�mih \ j t|rV\ j [�r j ]z�?u1rn\"w]�� � r h t�]?\ _ t c ��[ g ]z��~ ��[ _ l rV� � q � �5��� � l"h � d"g�c }"tk] � h ��t hk� ]?t e mBc � c3g �i]z\ h \ mil ] d�g ]?��]?\ _ ] c xg ]�rVt � mihs� ]#rV[�w hsc rV\"wy{ h w"] c u�� l ] g ]D]?\ cVgi�Zc ["�&�i] _ [ g�hkm�e {P["tk\"] g rV} h t hkmih ]?�NrVt g ]�rVw e ]�¢ h � m��� l ]Ã�i] m�mBh \ j [ d c x mBl ]z�i] d ]?� m�d�gic3j3g r � � � r e r _ m [�rVtkt e ] �Zd t cTe �­h �i["��]?� c x cnmBl ] g _ t|rn�i�i]z���[ _ l rn�¯} ePd rV���i]z� c3gI�Zh �i[��i] c x�rn[ mBl"cVgihkm�e u c3g&� r e }£] d tsrV\ m ]?wy{ h r _ cV�­d tk] m ]?t e \ c3g�� rVt�["�i]nurn� h \�r�tk] mim ] g } cV� } � � l ]#�i["}"��]� '["]z\ m ]�¢�] _ [ mihsc \ c x mBl ]�w"]zx®] gig ]?w �Zh �i[��i]?� � r e rVtk� cDg ]?t eZc \x®[ g�mBl ] g��Zh �i[��i] � ] mBl�c w"� � �#t m ] g \�r mih {V]?t e u�]�¢§] _ [ mBhkc \ � r eªh \f{ c tÂ{3] mBl ] c _?_ [ gig ]?\ _ ] c xN� c3� ]t c3j3h _ rVt)]z{V]?\ m ~®] �·j"� u r d r g9mBh _ ["tsr g w�r m ]ZrV\"w mBhk� ]nu c3g ryt c3j3h _ rVt _ c \"w hkmihsc \ � u c3g�� r e©g ]zt e«c \mil ] _ [ g�hsc � hkm�e u h \�\ c _ ]?\ _ ]Vu cVg \ c3gi� rVt�}�] l r�{ hsc3gDc x mil ]�{ h _ mihs�µ� q�\"w"]z]?w1u�}�] _ rV["��] r � gic � rV\l�c3g ��] m�e§d�h _ rntst e ]�¢�] _ [ m ]?��� hkmBlFmil ] d"g�h { h tk] j ]z� c x hkm �¾{ h _ mihs� ~ � � u hÂm � ]�¢�] _ [ mihsc \ � r eFg ]� '[ hsg ]I\ cx®[ g�mBl ] g½d"g�h { h tk] j ]z� � ¡ c3g ]�¢�r �Zd ts]nu"r � gic�� rn\§� l"cVg �i] d�gic3j3g r �*�­hkj3lfm ±�\�w hÂm ��]?tkx�rV[ mBl�c3gih�� ]?w micw�]?ts] m ]�rVtst mBl ]&{ h _ mihs� � ��±�tk]?� � � � gic � rV\§� l�c3g ��]�tk] mim ] g } c3� }«~®� hkmil�l"h w"w"]z\ _ c \ migic t _ l r g r _ m ] g �rn\"w©]?� _ r d ]��i]� '["]z\ _ ]z��� '[ hsg�g ]?tk]?w�r��½r e©h \ mBl ] m ]�¢ m �#�­hkj3lfm }�] l r gi� ts]z�i��[�\"ts]z�i��]�¢ d t h _ hkm t eg ]�rVw h \ m ] g�d"g ] mBh {V]?t e�c3gIcnmBl ] g � h ��]�]�¢§] _ [ m ]zw �Rl"c �N]�{3] g u h x mBl ]D� e � m ] ��d ] gi�Zhkm � mBl ] mBg rn\"� hÂmIc x��[ _ l _ l r g r _ m ] g �?u mBl ]­ts] mim ] g } c3� }4� c ["tkw }�]ÃrV}"tk] mic ]�¢ d t c3hkmDmBl r m ³Rr�� rV\"w }�] ]�¢�] _ [ m ]?w

` �

Page 58: Practical Architectures for Survivable Systems and Networks (Phase

[�\ � \ c � h \ j t e } e�mBl ];{ h _ mBhk��� o§]z{V] g rnt�]�¢ h � mBh \ j � e � m ] � �¶� mBh tst d ] gi�Zhkm�mBl ] h \ m ] gid"g ] m r mBhsc \ c x_ l r g r _ m ] g �?uRw"]z� d"hÂm ] mBl ]Dt c \ j � m ] gi� � \ c �&tk]?w j ] c x mBl�h � d"g�c }"ts] ���

�a��#$� � M >P=?E��)Q 3> � H = � =z>q�\ rVw"w hÂmBhsc \ mBcÃmBl ]�x cVg ] jVc3h \ j m � c x c3gi� � c x � rnt h _ hsc [��#r m�m r _ � ��~ } ePd rV���i]?��rV\"w d ]?� mDd"g�c3j3g r � � � u{nr gihkc ["��x c3gi� � c x)r m�m r _ � r g ] g ]?tsr m ]zw mBcFmil ] �Zh �i[��i] c x _ c \�x®] gig ]zw c3g r _ P[ hsg ]zwyrV[ mil"c3gihÂm�e3� q�\�w"]?]zw1umBl ]?�i]�r g ] mBl ] �Zc � m _ c3�­�Zc \Ãx c3g�� � c x�r m�m r _ � h \Ã� c3� ]¶]?\f{ hsg�c \ � ]?\ m �z�

� VSTH ��> � H = �)=?> E �FQ¸>P=?E��)Q 3>P= � � _ mBh {3] �­h �i["��] c x½r d"d r g ]?\ m t e _ c \�x®] g�g ]?w rV[ mBl�c3gihÂm�e©m�e§d �h _ rVtkt e rnt m ] g � mBl ]ª� m r m ] c x mil ]«� e � m ] � u c3g _ l rV\ j ]z�Ãw�r m rb~ ] �·j"� u � � � � � � � � ��� � T� u cVg } cVmBl1�� ¢�r �Zd ts]z� h \ _ ts["w�] �­h �i["��] c x1rVw �­h \ h � mBg r mBh {V] d"g�h { h tk] j ]z� c3g �i[ d ] g ["��] gNd�gih { h ts] j ]?� � _ l rV\ j ]z� h \r _?_ ]z�i� _ c \ mBg�c t d r g r � ] m ] g � mBc ]z\�rV}"tk] cVmil ] g5�­h �i["��]?� c x�rV[ mil"c3gihÂm�e ��l r g�� x®[�t�w"r m rFrnt m ] g r mihsc \rn\"w«x rVtk�i]Dw�r m rZ]?\ mBg9e � w"]?\ h rVtk� c x ��] g { h _ ]y~ h \ _ ts["w h \ j �Br m [ g r mBhsc \1uRw"]?tsr e u c3g¯d"g�c t c \ j r mBhkc \ c x��] g { h _ ] � � r j3j3g ]z�i� h {3] _ c {V] g�m _ l rV\"\�]?t ]�¢ d t c3hkm r mBhkc \1u1x c3g ]�¢"r �­d tk]Vu�["\'["��[�rVt g ]?� c [ g _ ]Z["�i] g ]����["t mih \ j x g�c3� w hkg ] _ m ["�i] g r _ mBhkc \ c3g } e ] � }�]?w"w"]zw � gic�� rn\ l"c3g �i]z� � rn\"w mil ]¯� c3� ]z� l r m ]�¢ cVmBh _�irVt|r �­h r m�m r _ � � h \­� l"h _ l \'[ � ] gic ["�N{3] g�e � � rntst d"h ] _ ]?��~ ] �·j"� u gic ["\"w§� c » � r g ] _ c tstk] _ m ]?w�~®] �·j"� ux cVg�d ] g � c \�rVt c3g _ cVgid�c3g r m ] j r h \ ��� � l ]�r d"d r g ]?\ m t e _ c \�x®] g�g ]?w+rV[ mil"c3gihÂm�e � r e l r�{3]µ}£]z]?\c } m r h \"]?wy��[ gig ] d�mihkmBhkc ["��t e u§}"[ m¯hkm �I["�i]�r d"d ]�r g �&t c _ rVtkt e rV� h x hÂm �N] g ]Dts] j3hkmihs� r m ] �

� 8#<�=�=�H���> � H = �)=?>«E �#Q¸>P=?E���Q 3>P= � � rn�i� h {3] �­h �i["��] c x�r d�d r g ]z\ m t e _ c \�x®] gig ]?wªrn[ mBl"cVgihkm�e�m�e§d �h _ rVtkt e�g ]?��["t m � h \ g ]�rVw h \ jZc x h \§x c3gi� r mBhkc \ � hkmil"c [ m rVt m ] g�h \ j rV\ e w�r m r�rV\�w�� hkmil"c [ m rVt m ] g�h \ jmil ]�� e � m ] � ~®� hÂmBl mBl ]�]�¢ _ ] d�mBhkc \ c x rV["w hÂm � mig r h tRrV\"wy� m r m [��Iw�r m r ��� � rV�i� h {3] �Zh ��["�i] h \ _ tk["w"]z�} gic �&� h \ j ~®� hkmil"c [ m � d ] _ h ± _ m r gij ] m � � u��i]?r g _ l�h \ j x c3g � d ] _ h ± _ d r m�m ] g \"�zu¾r _z_ ]z�i� h \ j w"r m ryr j �jVg ] j r m ]z� mBl r m r g ] �Zc3g ] �i]z\"� hÂmBh {V] mBl rV\ mil ] h \�w h { h w�[�rVt hkm ] � � ¹ �T�f  Ä u w g rT� h \ j©h \§x®] g ]z\ _ ]z�~®] �·j"� u�rV� h \ mBg r _ rV\"rVt e � h � mil r m5d ] gi�Zhkm � h \�x c3gi� r mihsc \ mic }�]�w"] gih {3]?w­� hkmBl�c [ m rV\ e r _?_ ]z�i� micw"r m r � u�rV\"w©\ c \�r j3jVg ]?��� h {3]�]�¢ d t c3hkm r mBhkc \ c x _ c {V] g9m _ l rV\"\"]zts�­~ � mBc3g r j ] cVg#mBhk�­h \ j _ l rn\"\"]?tk� � ux cVg ]�¢�r �Zd ts]nu g ]?�i[�t mBh \ j x gicV� ["\'["��[�rVt g ]�rVw h \ j r _ mBh { hÂm�e3� � l ]z�i]¶]z{V]?\ m � � r e�l r�{3]¶\ c r d�d"g ]��_ h rV}�ts]N]�»�] _ m c \ mil ] c } � ] _ m ��[��i]?w c3g c \ mBl ]I� m r m ] c x mBl ]I� e � m ] � ]�¢ _ ] d�m x c3g¾mil ]I]�¢§] _ [ mBhkc \ c x_ c3�Zd [ m ] g h \"� mig [ _ mBhkc \"� rV\"w mil ] g ]?��["t mih \ j rV["w hÂm w�r m r � � l ] e \�]?]?w;\ cVm h \f{ c tÂ{3]5["\�rV[ mil"c3g�h�� ]zw[��i] c x£�i] g { h _ ]z�Nrn\"w­� mBc3g r j ] � a ] g9m r h \Z]�{3]z\ m � mil r m �i[ d ] g ± _ h rVtkt e��­hkj3lfm r d"d ]�r g mic }�] d rV��� h {V]�Zh ��["�i] � r eZh \­x r _ mNg ]?�i[�t m½h \ r _ mBh {3] �Zh ��["�i] � x c3g ]�¢"r �­d tk]Vu mBl�gic [ jVl�mBhk� ]���w"] d ]z\"w"]?\ m � h w�]]�»�] _ m � �

�a��#$� � �;E��4O)<"Q�H =?E�J+E � S�ST< � �0E&%�>§=� h �i["��] c x¾rn[ mBl"cVgihkm�e�h � c x _ c \"� h w"] g rV}"tk] _ c \ _ ] g \ l ] g ]¶}�] _ rV["�i] hÂm _ rV\y}�]�]�¢ d t c3hkm ]?w h \Ã] hkmBl ] g½mBl ]h \�� m rntst|r mBhsc \ c3g�mBl ]y]�¢�] _ [ mihsc \ c x � rVt h _ hkc ["� _ c w"]VuIrn\"w�}�] _ rV["��] hkm�g ] d"g ]?��]?\ m �Ãr � r ��c3gFmBl�g ]�r m�Zc w�rnt hkm�eV� q�\ j ]z\"] g rVtvu'r m�m ] �­d�m � mBcDh \"� m rVtkt"rV\�w­]�¢�] _ [ m ] � rVt h _ hkc ["� _ c w�] � r e ] �Zd t c¸e r _ c3� } h \�r��mBhkc \ c x mil ] � ] mBl"c w"�&]?\'[ � ] g r m ]zwªrV} c {3]Vu£rV�I�5]?tst)rV� cVmil ] g ��]�¢ m ] g \�rVt mBc�mBl ] _ c3�­d [ m ] g � e � m ] � �zu�i[ _ l rV��� _ r�{3]?\ j3h \ j c x�w h � _ r g w�]?w � r m ] g�h rVtk�?u { h ��[�rVtI� dfePh \ j uNw"] _ ] d�mBhkc \1uN]?r�{3]?��w gicVd"d"h \ j u mBl ]zx m ul r g w��Nr g ] m r �Zd ] gih \ j u¾rn\"w � rV� '["] g rVw h \ j r m�m r _ � � � h \ _ ts[�w h \ j�d t|r e }�r _ � u � d£cPc ±�\ j u�rV\"w d"hsj �jVe }�r _ � r mim r _ � � ��mBl ]z�i]�r g ]�w h � _ ["���i]?w�} e²� ]z[ � rV\"\²rV\"w � r gi� ] g ¹ ^n�V� ÄK� ¡ c3g ]�¢�r �­d ts]Vu mBl ] ¿�h t e(#r _ � ] g � ¹ W3�3��u�W3�f  Ä ]�¢ d t c3hÂm ]zw mig r d w cPc3g �zu � rV� '["] g rVw h \ j u � gic�� rn\ l"c3g �i]z� mBc _ r d�m [ g ] d rV����� c3g w"�zu

� �

Page 59: Practical Architectures for Survivable Systems and Networks (Phase

rV\"w �Zh ��["�i] c xN~Kr _ '[ hsg ]?w � rV[ mBl"c3g�hkm�eV� � l ]¶q�\ m ] g \"] m¯¿4cVgi� ¹ Wf^n��u�Wf�n�§uRW3�3X Ä r mim r _ � ]zw�x c [ g w h »£] g �]?\ m�mBg r d w c§c3g �?u mil ] %�>� � � c3d�mihsc \ c x =?>PJ %'�4<�H L u ��>fS¸= ~ [��i]?w h \ mBl ] hk�­d tk] � ]?\ m r mBhsc \ c x � J �R>PQ � ug ] �­cnm ]¶t c3jVh \"�&]�¢ d t c3hkmih \ j � � � ��� ±�tk]?�?u�rV\�w ~ � c3� ]z� l r m�j3g r m [ hÂmBc [��it e�� r�x®]z� l ["\"w g ]?w d rV�i�9� c3g w"�c } m r h \�]?w } e �i]zts] _ m ]zw d"g ]z]?\ _ g�ePd�mBh {3] � r m _ l"h \ j r mim r _ � � � � l ] g ]?��["t m �½rV�µr ��]?tkx|� d"gicVd r j r mih \ j� c3gi� � hÂmBl { hsg ["�9�¼t hs� ] h \�x®] _ mihsc \yrV} h t hÂmBh ]?� �� l ] �Zc � m }"rV� h _ d ]z� m � d"gicVj3g r � d"gic }"ts] � h � mil ] � g�c�� rV\ l"c3g �i]nu#� l"h _ l _ c \ m r h \"� _ c w"] mBl r m

� l ]z\+]�¢§] _ [ m ]?w _ rn\ l r�{V] � rVt h _ hsc ["�F]z»£] _ m �«~ c3g ]�{3]?\br _?_ h w"]z\ m rVtst e w"]�{nrV� m r mBh \ j ]�»�] _ m � ��� � l ]h \�� m rntst|r mBhsc \ c x£r � gic�� rn\ l"c3g ��] c x m ]z\�] �Zd t cTe ��� e � m ] � {§[�ts\"] g rV} h t hÂmBh ]z�?u¸� l"h _ l�d ] g��­hÂm d ]?\"] mBg r mBhsc \} e ] hÂmBl ] g ["\"rV[ mBl�c3gih�� ]?w c3g rV[ mil"c3gih�� ]zw�["��] g � � ¡ [ g9mBl ] gi�Zc3g ]nu�� l ]z\F]�¢§] _ [ mih \ j u � g�c�� rV\ l"c3g �i]?� � r e]�¢ d t c3hkm�cVmil ] g {P["tk\"] g rV} h t hkmih ]z�D��[ _ l rV� mig r d w cPc3g � � q�\ rVw"w hkmBhkc \1u � g�c�� rV\ l"c3g �i]z� � r e _ rV[��i] mBl ]h \�� m rntst|r mBhsc \ c x)\"]�� mig r d w cPc3g � � � l ["�?u mil ] g ] _ rV\y}�]�r�� mBg�c \ j�h \ m ] g�g ]?tsr mBhkc \"� l"hsd }£] m �N]z]?\ � gic � rV\l"c3g �i]z� rV\"w mBg r d w cPc3g � � � hs� ]�} c3� }��¾rV\�w;t cVj3h _ } c3� }"� r g ]�� d ] _ h rVt _ rV�i]z� c x � gic � rV\ l"c3g �i]z� � ��] m�m ] g} c3� }"�5r g ] � ]?�i�ir j ]z� mBl r m r _ m rV� � gic � rV\ l"cVg �i]z�?u _ c \ m r h \ h \ j } c3j [�� c3g�h \ m ] gid�g ] mih {V]?t e ]�¢§] _ [ m rV}"tk]w�r m r �� ���� � ��^� � ��� � � � � � � � u rV�¶w"]z±"\"]?w } e aNc3l ]?\ ¹  n� Ä u h �Dr d�gic3j3g r � mil r m rVt m ] g � cnmBl ] g�d"g�c3j3g r � �

mBc h \ _ ts[�w"]4r _ cVd'e c x hkm �i]?tÂx � �#hsg [��i]?� c x m ]z\ ] �­d t cTe � g�c�� rV\§� l"c3g �i]�]z»£] _ m �?uDrV\"w mBl ] � gic�� rV\P�l"c3g �i]�]�»�] _ m � c x m ]?\©w�] d ]?\"w c \ mig r d w cPc3g � mBl r m r g ]F] hkmil ] g rnt g ]?rVw eµd"g ]?�i]z\ m�cVg�mBl r m r g ] _ g ]�r m ]?wx c3gZmBl ] c _?_ rV� hkc \ � � l ] g ] h �Ãr4t|r _ ��c x _ t|r g�hkm�e h \ m ] g��­h \ c t c3jVe _ c \ _ ] g \ h \ j { hsg [��i]?�zu¯� hÂmBl+m � cw h »�] g ]?\ m ��] m � c x&["�ir j ]Vu c \"]�x c3g � migih _ m �¼�i]?\��i] { hsg ["�i]z�?u rV\ cnmBl ] g x c3g;d ] g � c \"rVtÂ� _ c3�Zd [ m ] g { hkg ["��]?� �¿�l r m r g ] _ rVtkts]zw­{ hsg ["�i]z� h \ c3gihkj3h \�rnt�["�Br j ]�r g ]�["�i["rVtst e � g�c�� rV\ l"cVg �i]z� mBl r m r g ]#��]?tkx|� d"gicVd r j r mih \ j� hkmil"c [ m rV\ e \"] _ ]?��� hÂm�e²c x l [ � rV\ h \ m ] g {3]?\ mihsc \�~Krnt mBl�c [ j3lªd ] cVd ts] � r eªh \�rVw�{V] g�m ]?\ m t e x r _ h t hkm r m ]mBl ]�� d"g ]?rVw ���b¿�l r m r g ] _ rVtkts]zw { hsg ["�i]z� h \ mil ] d ] g � c \�rVtÂ� _ c3�Zd [ m ] g � c3g tkw+r g ]�[��i[�rVtkt e � gic � rV\l"c3g �i]z� mBl r m r g ] d"gic3d r j r m ]?w©} eªl [ � rV\©r _ mBhkc \ � � ] g � c \�rVt � _ cV�­d [ m ] g { hsg [��i]?�¶r g ] g r �­d rV\ m u1rn\"wg ] d"g ]z�i]z\ m r¯�i] gihsc ["�¾t c \ j � m ] g��0d"gic }"ts] � ~vo§] _ mBhkc \�^ � � � � ���¾º \ mBl ] cVmil ] g l rV\"w1un� migih _ m �¼�i]?\��i]N{ hsg ["�i]z�~®� l�h _ l r mim r _ lªmBl ] � �i]?tÂ{3]z� micÃcVmBl ] g�d"g�c3j3g r � �#rV\"w d"g�c3d r j r m ];� hÂmBl"c [ m�l [ � rV\�r h w � r g ]Fr g r g ]d"l ]z\ c3� ]?\ c \ � \ c \�];r g ] � \ c �&\ mBcZl r�{3]D}£]z]?\ d ] g�d ] mBg r m ]zw � rVt h _ hsc ["�it e u§rVt mil"c [ j3l r�x®]z� l rT{V]}�]?]?\ _ g ]�r m ]?w�]�¢ d ] gihk� ]z\ m rVtst e3�� � c3gi� h �¶r d"gicVj3g r � mBl r m¶h ��w h � migih }�[ m ]zw h \ mBc _ c3�­d [ m r mihsc \"rVt¾��] j3� ]?\ m � mil r m _ rn\�]�¢§] _ [ m ]

g ] �­cnm ]?t e3� q mF� r e }�] � rVt h _ hkc ["�?u c3g�� r e }£]­["�i]zw _ c \�� mBg [ _ mih {V]?t e � x cVg ]�¢�r �Zd tk]Vu micªd"gic { h w�]]�¢ m ]?\"� h {3] � ["t mihsd"g�c _ ]?�i� h \ j u§rn� h \ mil ] _ rV�i] c x mBl ]�]?r g t e �T�3�3XV��]�¢ d ] g�hs� ]?\ m �½} e o l"c _ l rV\"w (¯[ d"dr m � ] g�c ¢ � �#p a ¹ Wf�3� Äv� � l ]¶q�\ m ] g \"] m&¿4c3g�� d�gic { h w"]z�&r j3g r d�l"h _ h tstk["� mig r mihsc \ c x l"c � {P["tk\"] g rV}"tk]� cV� ]F� e � m ] � �Dr g ] mBc r�{nr g�h ] m�eªc x5r m�m r _ � � � q m¶h � h \ m ] g ]?� mBh \ j mBl r m u1]�{3]?\ mBl�c [ j3l � c3� ] c x mBl"c ��]{P["ts\�] g rn} h t hkmBh ]?���N] g ]I±�¢§]?w c3g�g ]?w"[ _ ]?w1uP]� '[�rntst e�l"c3g�gih }"ts]�{§[�ts\"] g rV} h t hÂmBh ]z� � mBh tst g ] � r h \ mBc w�r e3� ~ � l ]r g�j [ � ]?\ m�c {3] g � l ] mil ] g�mil ]�q�\ m ] g \"] m�¿ c3g�� �NrV�¶r�� c3gi� c3g r�{ hsg ["� h ��rV\©]�¢�r �Zd tk] c x5r � m ] g ��Zh \ c t c3jVe �Nr g � ��hÂm � g ]?� c ts[ mihsc \Ãw"] d ]z\"w"� c \y� l"h _ l �i] m�c x¾w"]�±�\ hÂmBhsc \"� h �&["��]?w �¦�

o§["} m ts]�w h »£] g ]?\ _ ]?� h \ mBl ] m�ePd ]z� c x � rnt h _ hsc [�� _ c w�]�r g ] g ]zt|r mih {3]zt e ["\ hs�Zd£c3g9m rV\ m?� p¯r mBl ] gNmBl rV\mBg9eÃmBcZ� r � ]�±�\"]Dw h � mBh \ _ mihsc \"�zu hkm&h � � [ _ l«�Zc3g ]Dr d�d"gic3d�gih r m ] mBc r m�m ] �Zd�m&mBc w"]�x®]?\"w«r j r h \"� m&mBl ]� rVt h _ hsc ["� _ c w"] m�ePd ]z��� e � m ] � r mBh _ rVtst e u�] �­d t cTe§h \ j r _ c3�Z�­c \�r d�d"gic r _ l�mil r mDh � _ r d rV}"tk] c xIrVw§�w g ]?�i� h \ j�mBl ]�[�\"w"] g t ePh \ j;d"g�c }"ts] � � � � l ] m ] _ l \ h '["]z�½x c3g rn\ h \ m ] j3g r m ]?w r d"d"g�c r _ l�mic _ cV� }�r m�mBh \ j� rVt h _ hsc ["� _ c w�]µ\�] _ ]z�i�ir gih t e _ c {V] g�mBl ]µ]z\ mBhsg ]Ã� d ] _ mBg [ � u�]�¢ _ ] d�m­d£c ��� h }"t e x c3g _ ] g�m r h \ {P["ts\�] g r¸�} h t hkmih ]z� mBl r m _ rn\ª}£] _ cV�­d tk] m ]?t e g ["tk]?w c [ m � x c3g ]�¢�r �Zd ts]nu£}�] _ rV["��] c x c3d ] g r mBh \ j ]?\f{ hsgic \ � ]z\ m_ c \"� mig r h \ m �&�i[ _ l rV�¯rVtst£� e � m ] � r _?_ ]?����}�] h \ j { h r l r g wP�¼� hsg ]?wyt h \"]?� mic­d�l'e � h _ rntst e _ c \ migic tkts]?w m ] g ��Zh \�rVtk� � � l [��?u j ]z\"] g�h _ w"]�x®]?\"��]?��r g ] �Zc3g ]�]z»£] _ mBh {V] h \ mBl ]�t c \ j�m ] g�� mil rV\yw"]zx®]z\"�i]z�¯r hs� ]?w c \"t e

� Å

Page 60: Practical Architectures for Survivable Systems and Networks (Phase

r m#d r g�mih _ ["t|r g r m�m r _ � � �D´ ]z� h w"]?�zu mBl ]Fr mim r _ �«�Zc w�]?� m ]?\"w mic � l"h x m � hÂmBl«mil ]Fw"]�x®]?\"��]?� � ¡ c3g�mil ]?��]g ]?rV� c \"�?u hkm¯h �¯\ cVm �i[ gid"g�h � h \ j�mBl r m�� rV\ eyc x mil ];w"]�x®]?\"� h {V] m ] _ l \ h P[�]?� h \ mil ];� e � m ] � ]�{Vrnts[�r mihsc \_ g�hkm ] gih r _ rV\b}�] l ]?t d x®["t h \ _ c3� }�r mimih \ j�� rVt h _ hsc ["� _ c w"]�rV\"w mig r d w cPc3g r mim r _ � �©~ rVt mil"c [ j3l mBl ]_ g�hkm ] gih r�r m#mBl ]Ft c �N] g ts]�{3]?tk��w c \ cnm ]�¢ d t h _ hÂm t eyd"g ]�{3]?\ m �i[ _ l r mim r _ � � ��� q m�h ��rVts� c \ cVm �i[ g�d"gih � h \ jmBl r m#h \ j ]z\"] g rVt mBl ]��i] m�c x m ] _ l \ h '["]?�#\"] _ ]?�i�ir g�e x c3g&d"g ]�{3]z\ mih \ jÃ� rVt h _ hkc ["� _ c w�] h �&{3] g�e _ t c �i]zt eg ]zt|r m ]?w mBc mil ] m ] _ l \ h '["]?��\"] _ ]?�i�ir g�e x c3g rT{ c3h w h \ j�mBg r d w cPc3g � � � l ]«�5]�r � �¼t h \ � \�r m [ g ] c x mBl ]�i] _ [ g�hkm�e�d"g�c }"tk] � ��[ j3j ]z� m �Nr _ t c ��] _ c [ d t h \ j }�] m �5]?]z\ mBl ] m � c�m�ePd ]?� c x�r m�m r _ � u§rV\"w mBl r m w�]zx®]?\��i]r j r h \"� m&c \"] m�ePd ] _ rn\�}�] l ]?t d x®["t h \µw�]zx®]?\�w h \ j r j r h \"� mImBl ] cVmil ] gIm�ePd ] �� rVt h _ hsc ["� _ c w"]¶r m�m r _ � �¯�i[ _ l rV� � g�c�� rV\ l"c3g �i]z��rn\"w � a { hkg ["��]?�¯r g ]�\ cVm rVw"]� '[�r m ]zt e _ c {3] g ]?w

} e�mil ]�]�¢ h � mBh \ j � e � m ] � ]�{Vrnts[�r mihsc \ _ gihÂm ] gih r � � l ]¶]�¢ h � m ]z\ _ ] c x)��[ _ l _ c w�]�� c [�tsw m�ePd"h _ rVtst e \"]z{V] g� l�c ��[ d�h \�r�� e � m ] � w"]z� hsj \1uf]�¢ _ ] d�m�d£c �i� h }"t e x c3g � � � ��� � ��� � gic�� rV\ l�c3g ��]?��~KrV\�]�¢ _ ]?]zw h \ j t e;g r g ]} g ]?]?w ��� � l ] e r g ];rVw"w g ]?�i��]?w d"g�hs� r gih t e�hs�Zd t h _ hkm t e } e�mil ] _ gihÂm ] g�h rZrV\"w g ] � r h \�r d"g�c }"tk] � ]z{V]?\h \ mBl ] �Zc � m rVw�{nrV\ _ ]?w²� e � m ] � �Z~KrVt mBl"c [ j3l«mil ] mBl"g ]�r m x gic3� ]�¢ m ] g \�rnt�r mim r _ � _ rV\©}�] g ]zw"[ _ ]zw h xmBl�c �i]¶� e � m ] � ��r g ] _ c \�± j [ g ]?w�rV\"wµ["�i]zw d"g�c3d ] g t e����q�\"w"]z]?w1uIw h »£] g ]z\ _ ]z� ]�¢ h � m r �­c \ j�mil ]�w h »£] g ]z\ m�m�ePd ]z� c x � rVt h _ hkc ["� _ c w�] d"g�c }"ts] � �zuN}"[ m hkm

h � mil ]­� hs�Zh tsr gihÂmBh ]z��rV\�w mBl ] c {3] g tsr d � mBl r m r g ] �Zc � mDhk�­d�c3g�m rV\ m�� �#\ e �i[ _z_ ]z�i��x®[�tNw"]�x®]?\"��] � ["� mg ] _ c3j \ h�� ] mil ]¶w h »£] g ]?\ _ ]?�¯rV\"w mBl ]D� hs�Zh tsr gihÂmBh ]z�?u'rV\�w«r _z_ c3�Z�Zc w�r m ]�} cVmBl��´ ["tktvu���rV\"w��5] l"g u � _ ¨�] gi�ZcVmim u�rV\�w aNl"cVh ¹ �T�V� Ķl r�{3]�w g r�x m ]?w r m r�¢ c \ c3�;ebmil r m _ tsrV�i� h ±�]z�

d"g�c3j3g r � ��] _ [ gihÂm�e ³Rr��&�yr _z_ c3g w h \ j mBc mBl ] �­cnmBh {V] ~ h \ m ]z\ mihsc \"rVt cVg h \�rnw�{3] g�m ]z\ m�� u mBl ] mBhk� ] c xh \ migic w"[ _ mihsc \ ~ w�[ gih \ j w�]z{3]zt c3d�� ]z\ m u � r h \ m ]z\�rV\ _ ]Vu c3g�c3d ] g r mBhkc \ � u½rV\"w d t|r _ ] c x h \ migic w"[ _ mBhsc \~ � c x m �Nr g ] c3g#l r g w§�½r g ] ��� � l ] e ��["}£w h { h w"] h \ m ]z\ mihsc \"rVt)³�rT�&� h \ mBc � rVt h _ hkc ["�¯rV\"w²\ c \ � rVt h _ hsc ["�zurV\"w � _ c \ mBh \'[ h \ j©c \ mBc x®[ g9mBl ] g �i["}"� mBg [ _ m [ g ] � mil ] e4d"gic { h w"]Ã]�¢�r �­d ts]?��x c3gF�Zc � m�c x mil ]?��]_ tsrV�i� h ± _ r mBhkc \"� � ( c �5]z{V] g uf� c3� ]Nw h � mih \ _ mBhsc \"�)r g ]�\ cVm¾� rVw�] � ¡ cVg ]�¢"r �­d tk]Vu mBl ] g ] h �)\ c w h � mBh \ _ mihsc \}�] m �5]?]?\ mBl ]�]�¢ h � m ]?\ _ ] c xNr ³Rr�� rV\"w hkm ��]�¢ d t c3hkm r mBhkc \1u£� l ] g ] mil ]Fx c3gi� ] g#� r e }�] h \"rVw�{3] g�m ]?\ mrV\"w mBl ]�t|r m�m ] g¯h \ m ]?\ mBhkc \�rVt � � g ]?��[ � rn}"t e u£��[ _ l©d"gic }"ts] � �&� h tkt)}�]Frnw"w g ]z�i��]?w h \«rV\ e ��["}"��]� '["]?\ m{3] g � hsc \"� c x mBl ] hsg � c3gi�R�� l ] g ]��i]?] � mBc }�]���] g�hsc ["� d"g�c }"tk] � � � hkmBl�mBg9ePh \ j mBc d r g�mBhÂmBhkc \ _ rV��]?� h \ mBc � rVt h _ hkc ["� rn\"w

\ c \ � rVt h _ hsc ["� h \ m ]?\ m �zu�}£] _ rV["��] c x _ c \�� h w�] g rn}"ts] _ c3�Z�­c \"rVt hÂmBh ]z� h \ mBl ] g ]�rnt _ rn["�i]z��rn\"w _ c \�� h wP�] g rV}"tk] c {3] g t|r d r �Zc \ j�mil ] _ c \"��]� '["]?\ _ ]?� � �#tk� c u d"g�c }"ts] � �5r g�h �i] h \ mBg�ePh \ j;mBc w h � mBh \ j [ h � l r �­c \ jl [ � rV\§� h \"w"[ _ ]?wµ]z»£] _ m �¯rV\"wµ� e � m ] � �Zh �i}�] l rT{ hkc3g?�q m�h �Dr���t hsd�d ] g�e ��t c3d ] mic r mim ] �­d§mDmic w"]�±�\"]­�i] _ [ gihÂm�e�d"gic }�ts] � � h \ m ] gi� � c x �­h �i["��]?� c x&rV[§�

mBl�c3gihÂm�e3� ¡ c3g ]�¢"r �­d tk]Vu mil ]�q�\ m ] g \�] m�¿4c3g�� �NrV�Nrn}"ts] mic ]�¢�] _ [ m ]�� hÂmBl"c [ m rn\ e ]�¢ d t h _ hÂm �­h �i["��]?� c xrV[ mil"c3g�hkm�e3� q�\ g ]?rVt hÂm�e u�\ c rV[ mBl"c3g�hkm�e �NrV��]�¢ _ ]?]?w�]?w h \ mil ]F]�¢�] _ [ mihsc \ c x mBl ]D±�\ j ] g w�rV] �­c \�u mBl ]["��] c x mBl ] �·gil�c � m ±�tk]?�zu mBl ]½��]?\"w � r h t�w"]z}"[ j¶c3d�mihsc \�u c3g¾mil ] _ c3dfe§h \ j¶c x�rV\�["\ d"gicVm ] _ m ]?wZ]?\ _ g�ePd�m ]?wd rV����� c3g wµ±�ts] ��o hs�Zh tsr g t e u � rV\ e c x mBl ]¶w"]z\ h rntÂ� c x|���i] g { h _ ]�r m�m r _ � �¯w c \ cVm \"]?]zw«rn\ e rn[ mBl"cVgihkm�eV�

�a��#$� � 8�>'Qn=zE£J�<�L|@ ��E��4O ��S�>PQ � H Q �)=?>P=� ] g � c \�rVt � _ cV�­d [ m ] g { hsg [��i]?� � r e r mim r _ �­h \Ãr�{nr g�h ] m�eZc x��Nr e �?u h \ _ ts[�w h \ j _ cVgig [ d�mBhkc \ c x mil ]�} c§cVm�i] _ mic3g u l r g w§��w h � ��d r g9mBhkmihsc \ m rV}"tk]?�zu c3g�� r h \ � ] �Zc3g�eV� � l ] e²� r e rVt m ] g#c3g t c _ � [ d ±�tk]?�zu _ g rn� lmBl ]�� e � m ] � uRrV\"w _ rn["�i]¶w"]zt|r e �&rV\"w cVmBl ] g w"]z\ h rVtk� c x)��] g { h _ ] � � l ]z�i] � a { hsg ["�i]z� m r � ]¶rVw�{nrV\ m r j ]c x mil ]�x r _ mNmil r m�mBl ] g ] h �5\ c � hkj \ h ± _ rV\ m �i] _ [ gihÂm�eZc3g � e � m ] � h \ m ] j3g�hkm�e�h \ mBl ]#� e � m ] � � c x m �Nr g ] � q�\

� �

Page 61: Practical Architectures for Survivable Systems and Networks (Phase

d"g r _ mih _ ]nu d ] g � c \�rVt � _ c3�­d [ m ] g { hsg [�� h \�x®] _ mBhkc \ h �½x g ]� '["]z\ m t e _ rV["��]?wµ} e _ c \ m r �­h \�r m ]zwÃw h r j \ c � mBh _d"g�c3j3g r � � �� l ]F\'[ � }£] g�c x�w h � mih \ _ m�d ] g � c \�rVt � _ c3�­d [ m ] g { hsg ["��� mBg r h \"� j3g ]���x g�c3� ±"{3]�r m#mBl ];}�] j3h \"\ h \ j

c x¶�T�V�3� micª�­cVg ] mil rV\ r mBl"c [��BrV\"w ]?r g t e�h \b�T�V�f^§u rn\"w l rV� _ c \ mBh \'["]?w micªj3gic � � m ]�rVw h t e � h \ _ ]mBl ]?\ ��´5e �T�3�3��\P[ � }£] g �I]�¢ _ ]?]zw h \ j �TX§u¦X3XVX��N] g ] _ cV�­�Zc \"t e P[ cVm ]zw � � l ]�\'[ � }�] g½h �½\ c � � [ _ lt|r gij ] g ufrV\�wZ� mBh tst jVgic � h \ j r m rV\ZrVt|r g��­h \ j#d r _ ] � � rV\ e w h »�] g ]z\ m�m�ePd ]?� c x � a { hsg ["�i]z�5rn\"w�{Vr gih rn\ mx c3g�� �¯]�¢ h � m�� � l ] j3g�c � mBlªh \ mil ];{ hsg ["� �Áh \�w"["� mig�e ��h ��]z\ c3g��­c [�� � q�\©rVw"w hÂmBhkc \1u"�5]�r g ]D}�] j3h \"\ h \ jmBcDc }"��] g {3]�� m ]�rnt mBl { hsg ["�i]z� mBl r m _ rV\ _ c \ _ ]�rVt mBl ] hsg ]�¢ h � m ]z\ _ ] h \­r¶{nr g�h ] m�e�c x��Nr e �½rV\"w�w h � migih }"[ m ]mBl ] � �i]?tÂ{3]z� � � r g9mBh _ ["tsr g t e w"rV\ j ] gic ["� h � mBl ]�] � ] gij ]?\ _ ] c x d£c t eP�­c3g�d"l"h _ { hsg ["�i]z�?u"� l"h _ l _ rV\ � [§�m r m ] c {V] g�mBhs� ]¯rV\"w­}£] _ c3� ] h \ _ g ]�rV� h \ j t e w h _ ["t m mBc w�] m ] _ m?� ¬�t mihs� r m ]zt e u mBl ]#rV\ mBh { hkg rVt mBcPc ts��r g ]t hk�­hÂm ]zw�} eµmBl ] hsg#h \ l ] g ]?\ m�h \ _ cV�­d tk] m ]?\"]z�i��rV\�w©} eµmBl ] gih w h _ ["t c [��it e � hs�Zd t h � mih _ r m�mBhkm ["w"] mBc �½r g w�i] _ [ g�hkm�e x c [�\"w h \ d ] g � c \"rVtÂ� _ c3�Zd [ m ] g�c3d ] g r mBh \ j � e � m ] � � � o§] gihsc ["� ]z» c3g�m � mic w"]�{3]zt c3d �i[ g { h {nrV}"tk]� e � m ] � ��� c ["tkw«w c �N]ztst mBc r�{ c3h w mBc w�r e � � d ] g � c \�rVt � _ c3�­d [ m ] g¯cVd ] g r mih \ j � e � m ] � �?u�rVt mil"c [ j3lymBl ]l r g w��Nr g ] h �&\ cnm&h \ mBg�h \"� h _ rntst e }�rnw �

�a��#$� ��S¸:�>PQ S�S�< � �0>fS¸:�E&%)=q�\©rVw�w hkmihsc \ mBc­mil ]�r m�m r _ �y� ] mil"c w��#\ cVm ]?w²rV} c {3]nu��i]�{3] g rVt cnmBl ] g ��r g ]�� c3g�mil w h � _ ["��� h \ j l ] g ] h \j3g ]�r m ] g w"] m r h tKu�\�r � ]zt e u mBl ] m ] _ l \ h '["]?��\P[ � }£] g ]zw � mBl"g�c [ j3l ����u�rV\"w«^VW h \ � rV}"ts]D^ � � �

� � � STQ�HKJ)=�H� � H = �)=?> � � ]?\"] g rVtkt e \ c \ m ] _ l \ c t c3j3h _ rVt¯rV\�w ["\ c }"��] g {3]?w�u#]�¢ migih \�� h _ �­h �i["��] h �d�l'e � h _ rntst e­g ] �­c {V]?wyx gic3� _ c3�Zd [ m ] g rV\�w _ c3�Z� ["\ h _ r mihsc \Zx r _ h t hkmih ]z� � q m½l rV�&\ c w hkg ] _ m t e c }§���] g {Vrn}"ts]­]z»£] _ m � c \ mil ] � e � m ] � ��rV\"w h �;["��[�rVtkt e ["\"w"] m ] _ m rn}"ts] } e�mBl ] _ c3�Zd [ m ] g ��] _ [ gihkm�e� e � m ] � � �¾l"c �5]z{V] g u hkm�� r e ts]?rVw mBc �i["}��i]� '["]z\ mFm ] _ l \ c t c3j3h _ rVt r mim r _ � � ��� ¢�r �Zd ts]z� h \ _ ts["w"]{ h �i[�rVtN� dfePh \ j ~ ] �Áj"� u g ] �ZcVm ] c }"�i] g {nr mihsc \ c x m�ePd ]zw � ] e � mBg�c3� ]z� c3g � _ g ]z]?\ hs� r j ]?� � u d"lfe � h �_ rVt � _ r�{3]z\ j3h \ j ~®] �·j"� u _ c tstk] _ mihsc \ c x5�NrV� m ] d r d ] g¶c3g�cVmil ] g ]�¢ m ] g \�rVtst e r _z_ ]z�i� h }"ts] _ c3�­d [ m ] g� ]?w h rÃ�i[ _ l rn��w h � _ r g w"� � � c � _ rVtkts]?w � � � � ��� ��� � � � � � T� u)rV\�w4{nr gihkc ["��x c3gi� � c xIw"] _ ] d�mBhkc \~®] �·j"� u �Zh � g ] d"g ]z�i]?\ m r mBhkc \ c x c \"]?��]?tÂx c3g¯c x g ]?rVt hÂm�e�� u�]�¢ m ] g \"rVt micZmil ] _ c3�­d [ m ] g � e � m ] � ��rn\"wm ]?tk] _ cV�­� [�\ h _ r mBhkc \"� � o§[ gid"g�h � h \ j t e u � rV\ eFh \ _ h w�]?\ m � l r�{3] h \f{ c tk{V]?w mil ]&w h � d£c � hkmihsc \ c x _ c3� �d [ m ] g � e � m ] � �&� l"c ��]¶�i]?\�� hkmih {V] _ c \ m ]?\ m � l r�{V]�\ cnm }£]z]?\«�irV\ hÂmBh�� ]?w c3g w"]zts] m ]?w �

� � !�=zS�> � � H = �)=?> � o e � m ] � �Zh ��["�i] m r � ]z� c \ m � c }�rn� h _ x cVgi� �?u d rn�i� h {3] c3g r _ mBh {V] �

� rn�i� h {3]¶� e � m ] � �Zh ��["�i] m ]?\�w"� mBc�l r�{3]�\ cZhk�­� ]?w h r m ]¯]�»�] _ m � c \ l r g w��Nr g ] c3g � c x m �½r g ]}�] l r�{ hsc3g u�rV\"w h \ _ ts["w�]?��t cVj3h _ rVt � _ r�{3]z\ j3h \ j ~®�i[ _ l rV�¶]�¢�r �Zh \"r mBhkc \ c x�w h � _ r g w"]zw _ c3� �d [ m ] g�� ]zw h r � rV\"wZ]?ts] _ migic \ h _ c3g cVmBl ] g�m�e§d ]?� c x�]�r�{3]z�iw g�c3d"d"h \ j;mBl r m�h \ m ] g _ ] d�m ��� hkj \�rVtk�?uc x m ]?\ � hkmil"c [ mNmBl ]�{ h _ mBhk� � �§� \ c �&ts]zw j ] �5� r�{3]z�iw g�c3d"d"h \ j�� r e }£] _ r gig�h ]zw c [ mIg ] �ZcVm ]zt e~ ] �Áj�� u�} e�d�h _ �'h \ j [ d ] � rV\"r mBhkc \"� �NcVg t c _ rVtst e ~ ] �Áj�� u�} e�d t|rV\ mBh \ j r­� dfe � m r d w"]�{ h _ ] h \�rm ] gi�Zh \�rntvu§� c3g�� � m r mihsc \�u � r h \�x g r � ]nu cVg¯cnmBl ] gIl r g w§�½r g ]��¼� c x m �Nr g ]D�i[�}"� e � m ] �����

� _ mBh {3]½� e � m ] � �Zh ��["�i] m�e§d�h _ rntst e¶l rV�¾� h w"]5]z»£] _ m � �'hkm)h \ _ tk["w"]?� mBl ]�x m c x _ c3�Zd [ mBh \ j ]� '[ hsd �� ]?\ m rV\�w d"lfe � h _ rVt�� mBc3g r j ] � ]?w h r �nl r g w§�½r g ] �Zc w h ± _ r mBhsc \"���i[ _ l rV� h \ m ] g \�rntst e¶d t|rV\ m ]zw� gic�� rV\P� l"c3g �i] l r g w��Nr g ]©w"]z{ h _ ]?� �Dh \ m ] g x®] g ]?\ _ ] ~ ]zts] _ mBg�c3� r j \"] mih _ u c3d�mBh _ rVtKu c3g cnmBl ] g � �d"lfe � h _ rVt�r mim r _ � � c \�]� '[ hsd�� ]z\ m rV\"w � ]zw h r�u5�i[ _ l rV� h \ m ] g�g [ d�mihsc \ c x cVgZm r �­d ] g�h \ j

� `

Page 62: Practical Architectures for Survivable Systems and Networks (Phase

� hkmil�d£c �5] g �i[ d"d t h ]z� c3g _ cPc t h \ j"� � l ]z�i]�r _ mBh { hkmBh ]?� l rT{V]�w hsg ] _ m ]�»�] _ m � c \ mBl ] _ c3�­d [ m ] g� e � m ] � �;~ ] �·j"� u h \ m ] g \�rnt1� m r m ] _ l rV\ j ]?��rV\"wR¥ c3g w"]?\ h rVts� c x¾��] g { h _ ] ���

� �0<�= ���)>'Q¸< %)HKJ � � � rn� '["] g rVw h \ j r mim r _ � � h \ _ ts[�w"] hk�­d ] g � c \"r mBhkc \ c x mBl ] h w"]z\ mihkm�eµc x�� c3� ]cnmBl ] g h \"w h { h w"["rVt cVg _ c3�Zd [ m ] g ��["} � ] _ m � � d�cPc ±�\ j r m�m r _ � � mBl r m m r � ]&rVw�{nrV\ m r j ] c x���[ _?_ ]?�i�9x®["thk�­d ] g � c \"r mBhkc \ �Rd"hsjVjVe }�r _ �'h \ j r mim r _ � � mBl r m#j r h \ d"lfe � h _ rVt r _?_ ]z�i� mic _ c3�Z� ["\ h _ r mihsc \µt h \"]?�cVg � c3gi� � m r mBhkc \"� � q � � d£cPc ±�\ j r mim r _ � � mil r m rnt m ] g5mil ]¶r d"d r g ]?\ m � hkm ]#x gic3� � l"h _ lymil ]�r m�m r _ �h � _ c3�Zh \ j �fd t|r e }�r _ � r m�m r _ � � mBl r m5� ] g ]zt e�g ] d ]�r m _ r d�m [ g ]?w c3g x rn} gih _ r m ]?w _ c3�Z� ["\ h _ r mihsc \�� �rn\"wÃ\"] m � c3g�� �N]?r�{ h \ j�mBl r m½� rV� � � d"lfe � h _ rVt�� l ] g ]�rn} c [ m �¯rV\"w gic [ mBh \ j { h rF} cVmBlÃm ]?ts] d"l"c \�]rn\"w _ cV�­d [ m ] g \"] m � c3gi� �zu�rV� d"g r _ mih _ ]zw©} e�mil ] ¿�h t e (#r _ � ] g � ¹ W3�3�§u�W3�3  Äv� � l ]?��]�r _ mih { hkmih ]?�� r e ["t mihs� r m ]zt e }�] h \"w h � mih \ j [ h � l rV}"tk]Zx g�c3� tk] j3hÂmBhk� r m ]�r _ mih { hkm�e u rVt mil"c [ jVl4mBl ] e4m�ePd"h _ rVtkt ecVgihsjVh \�r m ] �Zc � m t e rV� _ c3�Zd"g�c3�­h �i]z�½x gic3� c [ m � h w"] �

� �Ã>PJ)H <�L = E �;=z>PQ"��H�3> � � ] g�l r d � mBl ]�\"rV� mih ]?� m r mim r _ �«�Zc w�]?��� hkmil²g ]?� d ] _ m¶mBc ��[ g { h {nrV} h t hÂm�er g ] c x _ c [ g �i] mil"c ��] h \f{ c tk{ h \ j w�]?\ h rVts� c x��i] g { h _ ] � � rn}"ts]#^ � � h tsts[�� mBg r m ]z� mBl ] d ] g {V] g �i]�\�r m [ g ]c xRw"]?\ h rVts� c xR��] g { h _ ]I} e;h \ _ tk["w h \ j�mil ] ��h \ mil"g ]z]½w h »�] g ]?\ m _ t|rV���i]z�¯~K��u§���"ufrV\�wZ^VW � uVrVt mil"c [ jVl�5]­rVw"w mil r m rV\ e�c x mil ] d ]z� m�d"gic3jVg r � � _ rV\ }£]Z["�i]zw mBc _ rn["�i]­w"]?\ h rVtÂ� c x|����] g { h _ ]�r m�m r _ � �zurn� _ rV\µrV\ e } ePd rn�i� c x rV[ mBl�c3gihÂm�e3� � l ["�?u"�5] g ]?rVt h�� ] mil r m w"]z\ h rnts� c x ��] g { h _ ]Dr g ]�\ cVmIg ]�rVtkt e rd�gihs�Zhkmih {V] _ tsrV�i�zu�}"[ m r � ] m r _ t|rV��� c3g _ tsrV�i� c x _ tsrV�i��]?� ����¾w"] �­c \"� mig r m ]?wF} e¶mBl ]5w h � mBg�h }"[ m ]?w�w"]?\ h rVtÂ� c x|����] g { h _ ]�r m�m r _ � � h \ ¡ ]?} g [�r g9e ^nX3X3X�unrVt mil"c [ jVl��[ _ l r m�m r _ � � _ rV\ }£] _ r g�gih ]?w c [ m � hkmil"c [ m rV\ e r _ m [�rVt5rV[ mBl�c3gih�� ]?w r _?_ ]?�i� mic«mBl ]�� e � m ] � �~ l"c � m �)rV\"wD\"] m � c3g�� \ c w�]?� � ["\�w"] g r mim r _ � u � [ _ l��Zc3g ]�w"]z{nrV� m r mih \ j r m�m r _ � � _ rV\D}£]�tsrV["\ _ l ]?wjVh {3]z\ mBl ]�rV} h t hkm�e¶mic�d ]?\"] mBg r m ] � �#��r _ c \"��]� '["]z\ _ ]nu"w"]?\ h rVtk� c x���] g { h _ ]�r g ]&r m�mil ]&�Br � ] mBhk� ]{V] g9e ]�rV� e mBc�d ] gid ] mig r m ]DrV\"wy{3] g9e w h _ ["t mImicZd�gicVm ] _ m r j r h \"� m��

� l ] g ] � r h \ h \ j x c3gi� � c x)r mim r _ � t h � m ]?w h \ � rn}"ts]¶^ � ��r g ]�� c3� ]�� l r mI�Zc3g ] c }"� _ [ g ] mBl rn\ mBl"c ��]\ cVm ]?wµrV} c {3] � � l ] d ]?\'["t mBhk� r m ] _ rV�i] h \f{ c tk{V]?� �Zh �i[��i] mil"gic [ j3lyh \�r _ mBhkc \1u h \ � l"h _ l rF[��i] g u c3d ] g �r mic3g u§rVw �Zh \ h � mig r mic3g u � r h \ m ]?\�rV\ _ ] d ] g � c \�u c3gNd ] g�l r d �N�i[ g�gic3j r m ]�x r h ts� mic;m r � ]�rV\Ãr _ mBhkc \1uP] hÂmBl ] gh \ m ]?\ mBhkc \�rVtkt eÃc3g r _z_ h w�]?\ m rVtkt eV� o§[ _ l _ rV��]?� � r e t c3j3h _ rVtkt e }£] _ c \"� h w"] g ]zw²rV�#w"] j ]?\�] g r m ] _ rV�i]z� c x�Zh �i[��i]Vu�}�[ m r g ]¶t h � m ]?wy�i] d r g r m ]zt e }�] _ rV["�i] mil ] ey� r e l r�{3] '[ hkm ]¶w h »£] g ]?\ m¯c3gihkj3h \"� �� l ];±"\�rVt _ rV�i] h \ � rV}"tk]�^ � � h \f{ c tk{3]z��� e � m ] � ["�i]�rn��rV\ h \"w hsg ] _ m r h w h \ _ r g�g�ePh \ j�c [ m ��["}"�i]�� '["]?\ m r _ mBhkc \"� � ¡ r �­h t h r g ]�¢"r �­d tk]?� h \ _ ts["w�] d ] g x c3gi�Zh \ j ryw h _ mBhkc \�r g9e r mim r _ �²c \ rn\4]?\ _ g�ePd�m ]?w

d rV����� c3g w²±�tk]Vu�r m�m ] �Zd�mih \ j�micyh w"]z\ mih x e w h _ mBhkc \�r g9e � c3g w��D[��i]?w rV� d rn�i��� c3g w"�?u rV\"w d�c �i� h }"t e ["��h \ j ry�i] d r g r m ] � r _ l"h \"] mBcµ� r � ]Zw"] m ] _ mihsc \ c x mil"h ��r _ mBh { hÂm�e©l r g w"] g ~ ¹ ^3^VW Ä � � x r _ mic3gih \ jyc xN{V] g9et|r gij ]�\'[ � }�] g �?u�r m�m ] �Zd�mih \ jFmic } g ]�r � r d [�}"t h _ � � ] e ]z\ _ g9ePd�mBhkc \ � ] _ l rn\ h � � �i[ _ l rV� mBl ]Dp h {3]z� m �o l r �­hkg ����w"ts] � rn\ ~ p#o§� � rVt j3c3g�hkmBl���mBl r m w"] d ]?\�w"��[ d�c \²r d"g�c w"[ _ m�c x m � c t|r gij ] d"gihk� ]z�#}�] h \ jw h� _ ["t m�mBc x r _ mBcVg�� rV\�w©� _ rn\"\ h \ j �i[ _z_ ]?��� h {3] d"l"c \"];\P[ � }£] g �zu�r mim ] �Zd�mBh \ j­micÃh w"]z\ mih x eµ�Zc w"] � �mBl r m&�­hkj3lfm }�]�r mim r _ � ]?w��i["}��i]� '["]z\ m t eV�

�) � �������¾�"� �"� � �)��� $���9¼� %

� l"g ]�r m � mBc � e � m ] � rV\"wb\�] m � c3gi�bg ]?t h rV} h t hÂm�e _ rn\ m r � ] � rn\ e x c3g�� � � � l ] e _ rV\br gih �i]ªw"[ gih \ jg ]� '[ hsg ] � ]?\ m ��w"]z±�\ hkmBhkc \1uR� e � m ] � � d ] _ h ± _ r mBhkc \1u hs�Zd ts] � ]z\ m r mihsc \1u c3d ] g r mihsc \�u£rn\"w � r h \ m ]?\�rV\ _ ] �

� �

Page 63: Practical Architectures for Survivable Systems and Networks (Phase

��������� �8 �8� � ��������������� � � � � ��� � �<� � � � �e`y�t_��S�������� A�9�2403B/#���#L= ��0G%�&,=/+5#L=�9�!�J[9�H�%�#K!�9�2

� R � � �S� R ��� R �S�<�$���S�������:�F� q ���<����_,d�,� b �4�:]K���L�8O���]��f��V wp ��x�������� � � � �e`�O � �������S��� R Vf���� ����Vf���S���F�<Q R �f� � Vj� R Oy�<�S_��:�P� � ���:� R ��� ��R ������YG����� R Vf��oR �<���������� � �<���\�������P�,��_�� � � ���]L� R � � � � ���<� � � � �e`F��Y b �:` �$�:����� R �

�~!89�06&,=/!�J���03=/(>%?!�2:9�%?A/;<94Az%�#~94Hz%�#L!8942Z\� � �SV�_���� ��R �S�:����V:���c��� R�� V���� � � R �:]�� � ��a6�S�S��� VjV:� R ���S���>]�,��xh�:�PO � ����� � ����� � � R ]�� R O��<��_��:� ��R YG�S��e�S���,VX�������4�PO8�:�$� R O�� R �� R Vf������8������aoVf����*� R � V:�<� � � R ��R YG���������S��VX�S���S���

03B/B�J6#KD�!8%�#~!�=/B !8-�- J306;�!89403&$= 2�#K% ��03;#'9�H�%�#K!�9�2| ��R O8��xN�t� R � � �S� R ��� R �S� � V���V�_����F� R ��Q������ R ��]�Vf������_��4�sh����xN���:�t� R O�| �:�~����� � �:�h�,�?xN�UWV�V � O8� R �S������`gV:���S����������OyVf�8O8�

��!894!87 !�2�#���2:-I#L;0�� ;�94Hz%�#L!8942rjstkvuy���<Y��ext�<�S�W�$�?xN��oR ���:� R ����O����S��������� ��` R V�_���� R ��� ��� � � R � R O�V���V�_����F� R ��Q������ R �r � ����� � ��������O'O��<�S���������\V:� R � � �e�S� R V:`� �c������,���Prjstkvu'���<Y��ext�<�S�W����Q�����O8�4�P� R O��F� ��R �S� R � R Vf�� �c������,���PO������<�������� R �S� � ���P� R Og���$O��<���4�

�~#9�D�&,%194Hz%�#L!89�2������� �e` R �f�exh��� b Vf����$� R � R �S� q _�����S��]��S���8�S�:���:]K���S�:xt�<������]L�f��V wr � ����� � ��������O'��`8�e�S�:� ��` R V�_��S� R ��� �<� � � R�z����� Vj�����LV b ��Q�� � R OyVf� R Q��4�e� � � R

� -I#K%�!89�06=����S2�"�2�9�#L+ 9�H�%�#K!�9�2T ug���<Y��ext�<�S��O8��� � Q R � R O � �c�����:�c� R ����� � � R �,�?xN�� �c������,��� T u�V:� R �,Q�������� � � R� �c������,��� T ug����Q�����O8�4�t� R O��F� ��R �S� R � R Vf���� � �����S���h�<Y ����V b ���'� R Og�S�f�S� � � � �<�^�c�4V�_�� R � ���c�

� &$(>9SD*!8%�#���B�# �$#KJ6&�- +5#L=�9�-�%�&,7/J6#K+12������� �e`���`8�����:� O8��� � Q R � R O � �c�����:�c� R ����� � � Rp �L���h����� ��Y/���<Y��ext�<�S�j� R Q ��R ���:� ��R Q��S��V�_ R � dK�����st��O������Q����<�c� ��R Q�������Vf� � Vf�

��%?& �,%?!�+5+503= ���SJ3!�=��$A�! �,#g9�H�%?#L!8942�����c� � �����P��� R Q��,�<Q�� ��R ��O8�4dK����V � �4������c� � �����NO8��� � Q R � R O � �c�����:�c� R ����� � � R �$�?xN�

�~!8%�BzD�!�%?#v9�H�%�#K!�9�2�/���?xN� ��R _,�<��O8xh������O8�4� � Q R � R O � ����������� R �S��� � � Ri R O���� � ���<����� ��R �S�:� R �<�^_����SO�xh�����\�e������� ��� �S�:����� � � R �� �c������,���t_��<��O8xt�<�S�j�F� ��R ��� R � R V:�

f=�2403B/#��S#L= ��0G%�&$=�+1#K=�94!�J[94Hz%�#L!89�2�oR ���:� R ���$�$��xh�:�NO � �e�S���S��� R V:���uL�:��Y�a Q�� R �:�������4O ��P�<��_��:� ��R �S�:� R �<� ��R ������YG����� R Vf�

� �

Page 64: Practical Architectures for Survivable Systems and Networks (Phase

� l ] e _ rV\ c3gihkj3h \�r m ];x g�c3� l r g w��Nr g ] � rntkx®["\ _ mBhkc \"�?u c3d ] g r mih \ j ��� e � m ] � � c x m �Nr g ]�³Rr��&�?u)\"] m � c3g��� c x m �½r g ];³Rr��&�?u�r d"d t h _ r mBhkc \�� c x m �Nr g ] d�gic }"tk] � �?u c3d ] g r mBhkc \�rVt�] g�gic3g ��~®] �·j"� u h \«� e � m ] � _ c \�± j [ g r¸�mBhkc \1u � rV\�r j ] � ]?\ m u'rV\�w � r h \ m ]?\�rV\ _ ] � u']?\f{ hsgic \ � ]z\ m rVtRrV\ c3� rnt h ]z�?ufrn\"w � \ cnm�mBc }£] hsj \ c3g ]zw��l [ � rV\ �­h � m r � ]?� � o c3� ] h tstk["� mig r mih {V] m�ePd ]z� c x g ]zt h rV} h t hkm�e�mil"g ]?r m �¯r g ]��i[ �Z� r gih�� ]?w h \ � rV}"tk]D^ � ^ �� �i��]?\ mBh rVtst e ]�{3] g9e c \"] c x mBl ] m�ePd ]?� c x mBl"g ]�r m ���i[ �Z� r gih�� ]?w _ rV\ g ] d"g ]?��]?\ m rªx®["\�w�r � ]?\ m rVt

mBl�g ]�r mImBc�c {3] g rVtst���[ g { h {Vrn} h t hkm�e3�¾� \'{ hkgic \ � ]?\ m rVt mBl"g ]�r m � _ rV\µ}�] d r g�mih _ ["t|r g t e w"]�{Vrn� m r mBh \ j u"]?� d ]��_ h rVtst eÃh x ]� '[ hsd�� ]z\ m rV\"w � ]?w h r�r g ];��] gihkc ["��t e w�r � r j ]zw � � c ���i]?� c x d£c �5] g rV\�w m ]zts] _ c3�Z� ["\ h _ r��mBhkc \"� r g ]�]?� d ] _ h rVtst e _ g�hkmBh _ rVtKu d r g�mih _ ["t|r g t e#h x mil ] e tsrV� m x c3g t c \ j�d ] g�hsc w"� c x mBhk� ]�rV\�w h x"rVt m ] g \�r mBh {3]z�r g ]­\ cnm;g ]�rVw h t e rT{nr h t|rV}�ts] � � l"g ]�r m � mBc � c x m �Nr g ] rV\"w l r g w��½r g ] g ]?t h rV} h t hÂm�e _ rV\ l rT{V] d ] g {Vrn� h {V]]z»£] _ m �zu£rnt mBl�c [ j3lÃh \µ� c3� ] _ rV�i]z� mil ] e � r e }�]¶�i[ g��­c ["\ m ]?w �

�)�� � �������¾�"� �"� �«�������5�R(*� ,����

o e � m ] � rV\"w \"] m � c3gi�²d ] g x c3gi� rV\ _ ] _ rV\4}�] mil"g ]?r m ]z\"]?w rn�;r g ]z�i["t m;c x � rV\ e²c x mBl ] mBl"g ]�r m � micg ]zt h rV} h t hkm�e rV\"w©�i] _ [ g�hkm�e w h � _ ["���i]?w h \²o§] _ mBhkc \"�¶^ � ^ rV\"w�^ � �3u g ]z� d ] _ mih {V]?t eV� q�\²rVw"w hÂmBhsc \ mBc­mBl"c ��]mBl�g ]�r m �?u d ] g x c3g�� rn\ _ ] mil"g ]?r m �y]�¢ h � mÃmil r m w c \ cnm w hsg ] _ m t e � m ] � x g�c3� g ]?t h rV} h t hÂm�e c3g �i] _ [ g�hkm�eV�q�\�rVw§{3] g9m ]z\ m �Br m [ g r mBhkc \ c x g ]?� c [ g _ ]?� h � c \"] � r ��c3g _ tsrV�i�zu d ] gil r d ��}�] _ rV["��] c x g ["\�r��½r e�d"g�c3j3g r � �c3g h \�rVw�]� '[�r m ] j r g }�r j ] _ c tkts] _ mBhkc \ � � rV}"ts]NW � �½\ cVm ]?� � c3� ] c x mBl ] _ c \ _ ] d§m � c \F� l�h _ lFd ] g x c3gi� rV\ _ ]� r e w"] d ]?\�w �

�) � �«����� ���)���"�!N� �N, � �����)�¾��� ��� ���"!��!�� $�9��¼� %

� l"g ]�r m � mic �i[ g { h {nrV} h t hkm�e rV\�w hÂm � ��["} m ]?\"w"]zw g ]� '[ hkg ] � ]?\ m �µ]�¢ h � myd ] g {nrV� h {3]?t e+mil"gic [ j3l"c [ m rVtst� e � m ] � r d�d t h _ r mihsc \�r g ]�rn� �fmBl"g�c [ j3l�c [ m mBl ]&tsr e ] g � c x�rV}"� mBg r _ mihsc \ g ]zt|r m ]?w mBc¶l r g w��Nr g ]nu§� c x m �Nr g ]nurV\"w d ] c3d tk]«~ rV�Dw h � _ ["���i]?w h \4o§] _ mBhsc \4W � WµrV\"w4]zts��]z� l ] g ] h \ mil"h � g ] d�c3g�m � � rn\"w mil"gic [ j3l"c [ mDmBl ]� m r j ]z� c x#w"]z{V]?t cVd"� ]z\ m rV\�w+["��]«\ cVm ]?w h \+o§] _ mBhsc \ � � � � q�\ d r g�mih _ ["t|r g u mil"g ]?r m �­r g ] d ] g {Vrn� h {V]mBl�gic [ jVl"c [ m�mil ]I�i] g { h _ ]?� d"gic { h w"]zw�} e;mBl ] _ gihkmih _ rVt�\�r mBhsc \�rVt h \�x g rV� mig [ _ m [ g ]?��rV� �5]?tst"rV� _ c3�Zd [ m ] g �_ cV�­� [�\ h _ r mBhkc \ h \�x g rV� mig [ _ m [ g ]?� � � l ]?��] mil"g ]?r m � d"gic { h w"] mil ] �ZcVmih {nr mBhkc \ªx c3g�mBl ]­��[ g { h {nrV} h t hÂm�eg ]� '[ hsg ] � ]?\ m �&w h � _ [��i�i]zw h \ aNl r d�m ] g W �

� rV\ e mil"g ]?r m � mic �i[ g { h {nrV} h t hkm�e ]�¢ h � m�mBl r m�mBg rn\"� _ ]?\"w � e � m ] � w"]�{3]zt c3d"� ]?\ m rV\"w c3d ] g r mBhkc \ �º \ _ ] d r g�mBh _ ["tsr g t e \�rV� m�e ]�¢�r �­d ts] g ]z�i["t m ��x g�c3� ts] j3h ��t|r mihsc \ mBl r m¶h ��}�] j3h \"\ h \ j mBc � cVgi�ªhÂm ���Nr emBl�gic [ jVl ¬ � o � � m r m ]�tk] j3h �itsr m [ g ]?�zu�\"r � ]zt e u mil ]�¬�\ h x c3gi� aNc3�­d [ m ] g q�\§x c3gi� r mBhkc \ � g rV\"�ir _ mihsc \��� _ m ~K¬ a q � � ��� ¹ W3�V� Ä ��� c x¾YV["\"]�^VX3X3X§u"¬ a q � � l rV�¯rVt g ]�rnw e�d rV�i��]?w h \ ��hkgij3h \ h r�rV\"w � r g9e tsrV\"w �¬ a q � � ]?\ _ c [ g r j ]?� mBg r d w c§cVg � mBl r m _ rV\ ]z\�rV}"tk]�r©� c x m �½r g ]yw"]z{V]?t c3d ] g�mBc w h �irV}"tk] � h w"]zt e w h �9�mBg�h }"[ m ]?wy� c x m �½r g ] c \Ãw"] � rV\�w � �i[ _ l r � ] _ l rV\ h � � �­hkj3lfm ]�rn� h t e }�]�]�¢ d t c3hkm rV}"tk]�} e c [ m � h w"] g ��rn��5]?tst rV� mil ];w�]z{3]zt c3d ] g � �¶´ ]z� h w"]?�zu mBl ];w h � mBh \ _ mBhkc \µ}£] m �N]z]?\ h \"� h w"] g �#rV\"w c [ m � h w"] g � h ��\ cVm _ ts]?r g �_ [ m u�rV�¯�N] l rT{V]�rVt g ]�rnw e \ cVm ]zw � ¬ a q � � rVtk� c d ] g��­hÂm �¯w"]z{V]?t c3d ] g � mic rV}"� c tk{V] mBl ] � ��]?tÂ{3]?��x gic3�t h rV} h t hkm�e u�w h � _ c [ g r j ]z��� c [ g _ ]��r�{nr h tsrV}"ts]Z� c x m �½r g ]Vu5rVtst c �&�;w"]�{3]?t c3d ] g � mic x c3g } h w h \ m ] g�c3d ] g rV} h t hÂm�e� hkmil d"g�c3d"gih ] m r g�e²h \ m ] g x r _ ]z�?u�ts] j rVt h�� ]z� _ [ g�g ]?\ m t e c [ m tsr��N]zw rV}"["� h {V] d"g r _ mBh _ ]z�?u � mBh ³"]?� _ c3�­d ] mih �mBhkc \1u rV\�w h � j ]z\"] g rVtst e rn\ mihkmil ] mih _ rnt mBcªmil ]Ãw"]�{3]?t c3d"� ]?\ m�c x¯�i] _ [ g ]y�i[ g { h {nrV}"ts]�� e � m ] � � � ~ � l ]¬ � o � �T�V�3��¨ hsj3hÂm rVt � h tsts]z\"\ h [ ��aNcVd'ePg�hsj3lfm � _ m�h �&rVts� c�d"gic }�ts] � r mih _ rnt �¦�� cDjVh {3]¯r�w"] m r h ts]?w�]�¢"r �­d tk] c x mBl ]&} g ]�rVw mil­c x mil"g ]?r m � h \ � ["� m5c \"] _ g�hkmBh _ rVt � h \�x g rV� mBg [ _ m [ g ]5�i] _ �

mBcVg u _ c \"� h w"] g�mil ]��Br�x®] m�e � g ]?t|r m ]?w h �i��["]?� h \ mil ]F\�r mBhsc \�rVt r hsg � d r _ ]Vu�rV\�w mil ]F��["} m ]z\"w"]zw h ���i["]z� c x

� �

Page 65: Practical Architectures for Survivable Systems and Networks (Phase

�i] _ [ g�hkm�e rV\�w g ]zt h rV} h t hkm�eV� ~vo§]z]�x cVg ]�¢�r �­d ts]Vu � ]?[ � rV\"\ � � d£c � hkmihsc \¶� m r m ] � ]z\ m x c3g1mil ]�q�\ m ] g \�r mBhkc \�rVtaNc \�x®] g ]z\ _ ] c \«��{ h r mihsc \«o�rnx®] m�e rn\"w�o§] _ [ gihÂm�eµh \ mil ]�^§�?� m¶a ]z\ m [ g9e ¹ ^3�VW ÄK�À� �#ts]�¢�rV\"w"] g ¨ �£´ ts[§�� ]?\"� mBh ]zt1r mImil ]�¨�] d r g�mi� ]z\ m&c x � g rV\"� d�c3g9m r mihsc \ h \ a r � } g�h w j ]Vu � rV�i�ir _ l ["�i] mim �zu l rn� _ c \�w"[ _ m ]?wr g ] � r g�� rV}"ts]���] mDc x5� m ["w h ]z� ¹ �f�Pu��f�§u��' Pu��V��u��f�Pu)�VX§u)�P�3u��3 §u)�nW§u)�n�§u)�3�§u��V�§u)�V� Ä c {3] gDmil ] d rV� m��� e ]?r g � � q�\ l"h ����] gih ]?� c x g ] d�c3g�m �?u ´ tk[ � ]z\"� mih ]zt l rV��rV\�rVt e � ]?w � rV\ e©h ���i["]z� g ]?t|r m ]?w mic � e � m ] ��i[ g { h {nrV} h t hÂm�e h \ mBl ]�\�r mBhsc \�rVt&r hkg � d r _ ]nu5� hkmil � d ] _ h rnt¯] �­d�l rV� h � c \ _ c3�­d [ m ] g � _ c3�Z� ["\ h _ r mihsc \�i] _ [ g�hkm�e rV\�w g ]?t h rV} h t hÂm�e3�´ tk[ � ]z\"� mih ]zt � �)]?r g t eDg ] d�c3g9m �&~�T�3�f�

�T�3�3� � _ c \"� h w"] g ]?w mil ]N��["� _ ] d�mih } h t hkm�eDc x mBl ]½��w�{nrV\ _ ]?w��#[P�mBcV� r mihsc \Fo e � m ] � mic ]?ts] _ migic \ h _ r m�m r _ � rV\"w mil ]I]?tk] _ migic \ h _ ��] _ [ gihÂm�e�c x � ��o � tsrV\�rV\�w cnmBl ] g ¡ �����¨ � � e � m ] � � � o§["}"��]� '["]?\ m�g ] d£cVg�m � l r�{3] _ c \ mBh \'["]zw mBl"h �¾� m ["w e u'rVw"w g ]?��� h \ j r _?_ g ]?w hkm r mBhsc \Ã~9���3�3X�u�T�3�§�3u��T�3�f^ � u _ ] g�mBh ± _ r mBhsc \«~�T�3�f^ � u'r hkg � mic � jVgic ["\�w _ c3�Z� ["\ h _ r mihsc \��¯~9�T�3�VW � u'r hkg � mBg r _ � _ c \ mBgic t"�i]��_ [ gihkm�e ~9�T�V�3W � u rn\"w _ c3�Z� ["\ h _ r mihsc \��?u�\�r�{ hsj r mBhsc \1u rV\"w �i[ g {3] h tkt|rV\ _ ]²~9���3�V� � u x c3g ]�¢�r �Zd ts] � � cc [ gI� \ c �&tk]?w j ]nu mBl�h � h � mBl ] �Zc � m _ c3�Zd"g ] l ]?\�� h {V]¶�i] m¯c x mil"g ]?r m rV\�rVt e �i]?� c [ m � h w"] c x mil ] �­h t hÂm r g9e]?� m rV}�t h � l"� ]?\ m u � rV\"w mBl ]�} g ]?rVw mBl rV\"wªw"] d�mBl«c x mBl ]�� c3gi� w"]?��] g {3]?� _ r g ]�x®["t)] � ["tsr mBhkc \ h \ cnmBl ] g�i] _ mic3g � �� c }�] �Zc3g ]F� d ] _ h ± _ u ´ tk[ � ]z\"� mih ]zt � ��]�r g t e«g ] d�c3g9m � h \ _ ts[�w"]?w�r©�T�3�3�Ãrn�i�i]z�i� � ]z\ m ¹ �V� Ä�c x�{P["tÂ�

\"] g rV} h t hÂmBh ]z� c x mil ]«��w�{nrV\ _ ]?wb��[ mBc3� r mihsc \+o e � m ] � ~ �#��o �FmBc _ c3�Zd [ m ] g r mim r _ � � � � l ]ª�#��o�NrV� d tsrV\"\"]zw©r m#mil ] mihs� ];rn� mBl ]F\"]�¢ m � j ]z\"] g r mBhkc \ª� e � m ] � c x�r hkg � mig r _ � _ c \ migic t _ c3�Zd [ m ] g ��rn\"w_ c \ migic tkts] g w h � d t|r e ��x c3g�h \�� m rntst|r mBhsc \ h \­rntst"r hsg � mBg r _ � _ c \ mBg�c t _ ]?\ m ] g � ��´ tk[ � ]?\"� mBh ]zt � � � m ["w e x c [�\"w{P["ts\�] g rn} h t hkmBh ]?� mic r g rV\ j ] c x _ c3�­d [ m ] g r m�m r _ � � h \ mil"h ��� e � m ] � rV\"w g ] _ c3�Z� ]z\"w"]?w _ c ["\ m ] gi� ]�r¸��i[ g ]?� � ~®q�\ �T�3�3�§u mil ] ¡ �#� h �&±�\�rVtkt e }�] j3h \"\ h \ jZmic [ d"jVg rVw"] mBl ]�w h � d t|r e �?u g ] d t|r _ h \ j­m ] _ l \ c t c3jVex gicV� mil ] �Zh w§�B�T�3�3XV� �À� � l ] ¡ ��� � d ] _ h ±�]zw mBl ] _ c ["\ m ] gi� ]�rV��[ g ]z�µrV�Ãr g ]� '[ hsg ] � ]?\ m x c3gZmBl"h �� e � m ] �µ� ´ ts[ � ]z\"� mih ]?t½rVts� c rV�i��]?�i��]?w+{P["tk\"] g rV} h t hkmih ]z� c x mBl ] ¡ �#� � � � r mihsc \"rVt½� hkg � d r _ ]µo e � m ] �¨�r m r q�\ m ] g _ l rV\ j ] � ] m � cVgi� ~ � �#¨�q ��� uNr d r _ � ] m �¼��� hkm _ l ]?w�\"] m � cVgi� x cVg­h \ m ] g x r _ h t hkm�e _ c3�Z� [§�\ h _ r mihsc \ c x&r hkg � mBg r _ � _ c \ mBgic t�w�r m r ¹ �V  Äv�µ´ rn�i]?w c \ mBl�h ��rV�i��]?�i� � ]z\ m u ´ tk[ � ]z\"� mih ]zt d�g ] d r g ]zw r�i] _ [ g�hkm�eµ� rV\�r j ] � ]z\ m�d t|rV\yx c3g¯� �#¨�q � mil r m�l rV�¯}£]z]?\ hk�­d ts] � ]?\ m ]?w h \ mBl ]D� e � m ] � mBc­d"gicVm ] _ m_ g�hkmih _ rnt�w"r m r mig rV\"� �­h �i� hsc \"� � �#\ cVmBl ] g � m ["w e rV�i��]?�i��]?w {§[�ts\"] g rV} h t hÂmBh ]z� c x mBl ] � c3h _ ]ÃoP� hÂm _ l"h \ jrV\"w aNc \ mBgic tNo e � m ] � ~ � o a o ��� � l ] � o a o h �;r _ c3�Zd [ m ] g¶mBl r m _ c \ mBgic ts� mil ]Z��� hkm _ l"h \ jªc x&r hkg �mBg r _ � _ c \ mBg�c t _ c3�Z� ["\ h _ r mBhsc \"�¯~ }�] m �5]?]z\ _ c \ mBg�c tstk] g �5rn\"wZ³ hsj3lfm _ g ]��&�½rV\�w�}�] m �5]?]?\ _ c \ mBg�c tstk] g �c \ mBl ] j3gic [�\"w � r m rntst r hsg � mBg r _ � _ c \ mBg�c t _ ]?\ m ] g � � �#\ cnmBl ] g � m [�w e ¹ �§� Ä�h w"]?\ mih ±�]zw rn\"w²rV�i��]?���i]?wgih � � � mBc r hsg mig r _ x gic3� ]zts] _ mBg�c \ h _ r mim r _ � � c \ mBl ]¯]?\ mihsg ] � r mBhkc \�rVt"� hsg o d r _ ]#o e � m ] � u h \ _ ts[�w h \ jr hkg � mig r _ � _ c \ migic t _ c3�­d [ m ] g �?u g rVw"r g �zu1��� hÂm _ l"h \ j � e � m ] � �?u1rV\"w²rV[ mic3� r m ]zw � r h \ m ]z\�rV\ _ ] h \§x c3g �� r mBhkc \ � � l"h ��� m ["w eªd�gihscVgihkmih�� ]?w�rVtst mBl ];� e � m ] � � h \ m ] gi� � c x�{P["tk\"] g rV} h t hkmih ]?�&rn\"w mBl ] d£cnm ]?\ mih rVths�Zd r _ mNc x��i[ _z_ ]?����x®["t�r mim r _ � � c \Ãr hkg5mBg r _ u h \ _ ts["w h \ j¶mBl ] d�cVm ]?\ mBh rVt�x cVg _ g rV� l ]?�&rV\�w mBl ] _ c � mNc xd�cVm ]z\ mih rVt'w"]zt|r e �?u'rV\�wF]?� mBhs� r m ]?w mil ] c {3] g rVtkt g�h � ���¾´ ts[ � ]z\"� mih ]?tPrVtk� c�d�gic w"[ _ ]zw mBl ]5�i] _ [ g�hkm�e�d t|rV\��x c3g ¡ ����� e � m ] � � g ]� '[ hkg ]zwF} e � ["}�t h _ ��r�� �TX3X��^VWf�§u�rV[ mBl"c3g ]?w ¡ �#� � � g ]� P[ hsg ] � ]z\ m � x cVg _ c3�­d [ m ] g�i] _ [ g�hkm�e r _?_ g ]?w hkm r mBhsc \ ~Krn\"wªw"]z� hsj \"]?w²rV\�w©w"]z{V]?t cVd ]zw©� c x m �Nr g ] mic rV[ mic3� r m ] mBl ]Fr _?_ g ]?w hkm r mBhsc \g ] d£cVg�mBh \ j;d�gic _ ]?��� � rV\�wÃ�i]?\�� hkmih {V]�r d"d t h _ r mBhkc \ _ ] g9mBh ± _ r mihsc \ ¹ �VW§u��n�§u��3� Äv� (¯]�rV[ mil"c3g ]zw mBl ] � q9o �� [ h w"]zt h \"]?� ¹ �3^ Ä�c \ ¡ �#� ��q9oÃ��] _ [ gihÂm�e r _z_ g ]zw hkm r mBhkc \ � (¯]��½rn� mBl ] d"g�h \ _ hsd rnt�rV[ mBl"c3gNc x mBl ]DYV[�\"]�T�3�VWÃp¯] d£c3g9m�mBc�aNc \ jVg ]?��� c \ � hsg � g r _ aNc \ mBg�c t ¨�r m rÃrV\"w aNc3�­� ["\ h _ r mBhkc \"� � ["ts\"] g rV} h t hÂmBh ]?�rV\"wªo§] _ [ gihÂm�e ¹ �V� Äv� �#w�w hkmihsc \�rnt�� m [�w h ]z�#["\"w�] g�´ ts[ � ]?\"� mBh ]?t � �&w hsg ] _ mBhsc \ h \f{ c tk{V]?w©rV���i]z�i� � ]?\ m � c xr hkg � mig r _ � _ c \ migic t m ]zts] _ c3�Z� ["\ h _ r mihsc \���� e � m ] � � mic ]?ts] _ migic \ h _ r m�m r _ � �zuRrV\"wÃw"]�{3]?t c3d"� ]?\ m&c x mBl ]� 2:,) 6�21)*�*�1��)b+B/?6�,)�-430�*+B,/TK%�,/L�<35%W� E 'B� �@*b'B21-���/1&*�*+B��':30� � ! � � � ! � _ � ! �1� _?� �Q*b'B21-���/1&*�*+B� � ML,'B�Y� � # >?,5��# =,QM ( ,)7<935)�)�I?' �",8181+B/?&�K;2 EVE4���%�� ,56'�b+ M?+B' E M�+H30��+B,/@����%�21)�+ �JIW4X�Y��)<30�*+B,/1&�K &J/L�*�Q)*/:35'R35/1> E &�� *b)�35/1%<�T#

� �

Page 66: Practical Architectures for Survivable Systems and Networks (Phase

� mig r m ] j3h _ d t|rn\ mic�d"gicVm ] _ m ��[ _ l � e � m ] � � �¿�hkmil g ]z� d ] _ mÃmic mBl ]©\�r mBhsc \�rVt�r hsg � d r _ ]Vu�rV\"w � hkmil g ]z� d ] _ mymic mBl ] cVmil ] g \"r mBhkc \�rVt h \�x g rV�9�

mBg [ _ m [ g ]z�;rn\"w mil ] _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mBhsc \ h \�x g rV� mig [ _ m [ g ]?�zu hÂm¶h � _ tk]�r g�mil r m¶mBl ] mil"g ]?r m ��r g ]d ] g {nrV� h {V]VuI]?\ _ c3�Zd rV��� h \ j } cVmBl�h \ m ]z\ mihsc \"rVt¯rV\"wbr _?_ h w"]?\ m rVt _ rV["��]?� � ( c �5]z{V] g u hkmZh � _ ] g�m r h \�t e["\ d�c3d [�t|r g&mBc w h � _ ["��� mBl ]z�i] mBl"g ]�r m � c3d ]?\"t e u£rV\"w mil ["� mil ] eµm ]z\"w mBc }£]Dt|r gij ]zt e w c �&\ d t|r e ]zw �h x)\ cnm rnt �Zc � m _ c3�Zd ts] m ]?t e�hkj \ c3g ]?w �q�\ j ]z\"] g rVtvu hkmNh �5{V] g9e w h� _ ["t m x c3g rn\ c3gij rV\ h�� r mBhkc \ mic ]�¢ d ]?\"w g ]?� c [ g _ ]?� c \ ]�{3]?\ m � mil r mIl rT{V]

\ cVm5l r d�d ]z\"]?w c3g mBl r m r g ] d ] g _ ] h {V]?w mBc }£]¯{3] g�e ["\"t hs� ]zt e�mic;c _?_ [ g?� � l ] hs�Zd£c3g9m rV\ _ ] c x g ]�rVt h � mih _mBl�g ]�r m rV\�w gih � � rn\�rVt e ��]?� h � mBl r m�hÂm }�] _ c3� ]?� � [ _ l ]?rV� h ] g mBc � ["� mih x eFmil ]�]�» cVg�m rV\"w�]�¢ d ]z\"w hkm [ g ]z�h x r _ tk]�r g w"] �­c \"� mig r mihsc \ c x mBl ] g�h � � � _ rV\�}�] � rnw"] �

� �

Page 67: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� ��� � � ��� � � ����� � � � � � � � �

��� ��� � ��� � � � � � � �

� � � � � ��� � � � �& � � � ��� � � � �� � � � � � � � � � � � � ��� � � � ���� ������ � �� � ��� � � �& � � � ��& ����� � � � ��� �� r j r g � ["\�r�u��i] _ c \"w§� _ ]z\ m [ g�e�´ [�w"w l"h � m¯d"l"h t c � c3d"l ] g

¿ ]�\"]�¢ m ]?tsrV} cVg r m ] c \ mBl ] g ]� P[ hsg ] � ]z\ m �?u mil"g ]?r m �zu gih � � �?u&rV\�w g ] _ c3�Z� ]z\"w�r mihsc \�� c [ m t h \"]zwh \ ¹ ^V� Ä rV\"w�w h � _ [��i�i]zw h \ aNl r d�m ] g � c x mBl"h � g ] d£cVg�m u h \��i[ _ l r��½r eFmil r m mil"c ��] g ]� '[ hkg ] � ]?\ m � _ c ["tkwr d"d t e } g�c rVw"t e�mBc rD� h w"] g rV\ j ] c x1�i[ g { h {nrV}"ts]¯� e � m ] � w"]z{V]?t c3d"� ]?\ m �NrV\"w mic�mBl ] d"g�c _ [ g ] � ]z\ mNc x� e � m ] � �&� hkmBl _ gihkmih _ rVt g ]� '[ hsg ] � ]?\ m �&x c3g ��[ g { h {nrV} h t hÂm�e3�

º [ g r d�d"gic r _ l�h � gicPcVm ]zw h \ mBl ]D]z� m rV}"t h � l"� ]?\ mIc x rF� c ["\"wµ}�rV� h _ �i] m¯c x j ]?\"] gih _ g ]� '[ hkg ] � ]z\ m �x c3g �i[ g { h {nrV} h t hÂm�e rV\�w mBl ]­]�¢ d t h _ hkm w"] m ] gi�Zh \�r mihsc \ c x l"c � ��[ g { h {nrV} h t hÂm�e«h \ m [ g \ g ]� P[ hsg ]z� cnmBl ] g�i] _ c \�w�r g�e�d"gicVd ] g�mBh ]?� � o§] _ c \"w�r g�e d�gic3d ] g9mBh ]z� h \ _ tk["w"]�{nr g�hsc [��NrV� d ] _ m � c x��i] _ [ g�hkm�e­h \ d�g ]z{V]?\ mBh \ j� h tktkx®["t �­h �i["��] �Pg ]?t h rV} h t hÂm�e u�x rV["t m�mic ts] g rV\ _ ]Vu§rV\"w g ]z� c [ g _ ]#rT{nr h t|rV} h t hÂm�e w"]?� d"hkm ]#r _z_ h w"]?\ m rntRx r h ts[ g ]?�~®� hÂmBl g ]�rVt � mBhk� ]Zr�{nr h tsrV} h t hkm�e � l ]?\ g ]� '[ hsg ]?w � � _ ] g�m r h \ rV� d ] _ m � c xIx®["\ _ mBhkc \�rVt _ c3g�g ] _ m \"]z�i� � ]�rV��]c x�["�i] �&g ] _ c \�± j [ g rV} h t hÂm�e ["\�w"] g w"[ g ]?��� � rV\"w � c3� ]Ã�i]z\"�i] c x c {V] g rntstI� e � m ] � g�c }"["� m \"]z�i�­� l ]?\x rV["t m �F]�¢ _ ]?]zw mic ts] g rV} h t hÂm�e3� q�\ m [ g \1u �i] _ [ g�hkm�e g ]� '[ hsg ] � ]?\ m � h \ _ tk["w"] h \ m ] j3g�hkm�e c x�� e � m ] � �­rn\"w\"] m � c3g��'h \ j u _ c \�±�w�]?\ mBh rVt hÂm�e mBc r�{ c3h wbw h �i��] �Zh \�r mBhsc \ c x h \�x cVgi� r mBhkc \ mBl r m _ c ["tsw�}£]�["�i]�x®["t micr m�m r _ � ] g �«~ ]z� d ] _ h rVtkt e _ g�ePd�mic3j3g r d"l"h _ � ] e � rn\"w rV[ mBl ]?\ mBh _ r mihsc \ d r g r � ] m ] g � � u l"hsj3l r�{nr h tsrV} h t hkm�erV\"w d"g ]z{3]z\ mBhsc \ c x¾w"]?\ h rVtk� c x ��] g { h _ ]¶w"]z� d"hÂm ] � rnt h _ hsc [��½r _ mBhsc \"�?u�rn[ mBl"cVgih�� r mBhkc \1u�r _?_ c ["\ m rV} h t hÂm�e ug r d"h w�w"] m ] _ m rn} h t hkm�eFc x1rVw§{3] g �i]¯� hÂm [�r mihsc \��?ufrV\�w d"g ]z{V]?\ mBhkc \ c x cVmil ] g x c3g�� � c x �Zh ��["�i] � p&]?t h rV} h t hkm�eg ]� '[ hsg ] � ]?\ m � h \ _ tk["w"]�x rV["t m�mic ts] g rV\ _ ]Vu¾x rn["t m w"] m ] _ mBhkc \ rV\"w g ] _ c {V] g9e u�rV\"w g ]?� d£c \��i]?� mic ["\�]�¢'�d ] _ m ]?wÃx r h ts[ g ] �Zc w"]?� � o§] _ [ gihÂm�e rV\�w g ]?t h rV} h t hÂm�eFl r�{V]�� c3� ] g ]� '[ hsg ] � ]?\ m � mBl r m r g ] g ]?tsr m ]zw1uP�i[ _ lrV� g ]z� h � m rn\ _ ] mBc ]zts] _ mBg�c3� r j \"] mih _ rn\"w cnmBl ] g�h \ m ] g x®] g ]?\ _ ] � ¡ [ g�mil ] g��­c3g ]Vu�� c3� ] c x mil ] g ]� '[ hkg ]��� ]?\ m � h \ m ] g r _ m � hkmil4cVmil ] g�g ]� P[ hsg ] � ]z\ m �?u rn\"w � ["� m }�] l r gi�Zc \ h�� ]?w mBc ]z\"�i[ g ] mBl r m�mil ] e r g ]\ cVm _ c \ mBg rVw h _ mBcVg�e3�ª� r _ l g ]� '[ hkg ] � ]?\ m�l rV� � rV\ h x®]z� m r mBhkc \"��r m ]�r _ l t|r e ] gFc x�rV}"� mBg r _ mBhkc \1u�rn\"w_ cVgig ]z� d�c \"w h \ j � d ] _ h rVt h ���i["]z� mil r mD� ["� m }�]­r _?_ c3�­�Zc w�r m ]zw � � r g9mBh _ ["tsr g t|r e ] g � c xIrn}"� mig r _ mBhsc \� ["� m rVw"w g ]?�i� g ]zts]z{nrV\ mZd"g�c3d ] g�mih ]?��� c x�r d"d t h _ r mBhsc \"�?u w�r m rV}�rV��]?�zu½� e � m ] � �?u½��["}"� e � m ] � �zu�rn\"w\"] m � c3g��'h \ j � c x m �Nr g ] � � ePd ]?� c x½rnw�{3] g � hÂmBh ]?� mBc }�] _ c {3] g ]?w } e©mBl ] g ]� '[ hsg ] � ]?\ m � � ["� mDh \ _ ts["w"]mBl ]�x®[�tst¾� d ] _ mig [ �/c xNr d"d t h _ rV}"tk] d£cnm ]?\ mih rVt mil"g ]?r m �zu��i[ _ l rV� � rnt h _ hsc [��#� c x m �½r g ]�rn\"w l r g w§�½r g ]

� �

Page 68: Practical Architectures for Survivable Systems and Networks (Phase

r m�m r _ � �?u�� e � m ] � � rVtkx®[�\ _ mihsc \"�zu�rn\"wª]?tk] _ mBgic \ h _ h \ m ] g x®] g ]?\ _ ]�\ cVm ]?w²rV} c {3] � ��tst g ]?rV� c \"rV}"ts] gih � � �� ["� m }£]�rV\ mih _ hkd r m ]?w�rV\"w d"g�cVm ] _ m ]zw4r j r h \�� m�� � l [��?u c [ g r d"d"g�c r _ l�h ��w"]�{3]zt c3d"h \ j rÃ� c3� ]z� l r m_ rn\ c \ h _ rVt g ]� '[ hkg ] � ]z\ m �½x g r � ]z� c3g�� x c3g ��[ g { h {Vrn} h t hkm�e�mBl r m ]?\ _ c3�Zd rV���i]?�¯rVtkt mil ] g ]zts]�{Vrn\ m&h �i��["]?�zurV\"w mBl r m w"] �Zc \"� mBg r m ]z� l�c � mBl ]¶w h »�] g ]z\ m¯g ]� '[ hsg ] � ]?\ m � h \ m ] gig ]?tsr m ] �º x d r g9mBh _ ["t|r g5hk�­d�c3g�m rV\ _ ]�r g ] mBl ]��½r e � h \�� l"h _ l � c3� ] c x mil ]?��] g ]� '[ hkg ] � ]?\ m � h \ m ] g r _ m � hkmil

c \"]�rn\ cVmBl ] g u1rV\"w l"c � � l ]?\²� e � m ] � �Dr g ]Fw�]z{3]zt c3d ]?w mBc �ir mBh ��x eµmBl"c �i] g ]� '[ hsg ] � ]?\ m �zu mBl ] _ c3� �d�c \"]?\ m � �i[ d�d£c ��]?w"t e rVw"w g ]?�i� h \ j w h »£] g ]?\ m g ]� '[ hsg ] � ]?\ m � r _ m [�rVtst e h \ m ] g r _ m � hÂmBl�c \"]ªrn\ cVmBl ] g?�q�w"]?rVtst e u hÂmFh � l ]?t d x®["t h x mBl�c �i] h \ m ] g r _ mihsc \��Fr g ] ["\"w"] g � mBcPc w r l ]�rVw c x mihs� ] g r mBl ] g;mBl rV\ � rn\ h �x®]?� mBh \ j«mBl ] � �i]?tÂ{3]z� � [ _ l t|r m ] g�h \ mil ] w"]�{3]zt c3d"� ]?\ m�d�gic _ ]?���?u c3gFh \ � e � m ] � ["�i]nu�rV�F�i]z] �Zh \ j t ec }"� _ [ g ]D{P["tk\"] g rV} h t hkmih ]z�?u'³Rr��&�?u gih � � �?uRrV\�w h \y� c3� ] _ rV��]?� _ r m rV� migic3d"l ]?� �¡ c3g rn\ e«j3h {V]?\�r d"d t h _ r mBhkc \1u mBl ];� d ] _ h ± _ g ]� '[ hsg ] � ]?\ m � � ["� m }�]�w"] g�h {3]zw©x gic3� � \ c �&ts]?w j ] c x

mBl ] c3d ] g r mBhsc \�rVt']?\f{ hsg�c \ � ]?\ m u mil ] d ] g _ ] h {3]?w mil"g ]?r m �zu mBl ]½]�{nrVts[�r m ]?w gih � � �?u � rV\ e;cVmil ] g d"g r _ mBh _ rVt� r mim ] g �¾�i[ _ l rV� mBl ]I]�¢ d ] _ m ]zw�w h� _ ["t m�e rV\�w _ c � m � \"] _ ]?�i�ir g�e�mic¶hs�Zd ts] � ]z\ m mBl"c �i] g ]� '[ hsg ] � ]?\ m �zumBl ]�r�{nr h t|rV}"tk] g ]?� c [ g _ ]?� h \Fx®["\"w h \ j rV\"w � rV\ d�c �5] g u'rV\"w _ c \�� h w�] g r mBhsc \"� c x l"c � mBl ] d ] _ ["t h r g�hkmBh ]?�c x mBl ] j3h {V]?\�r d"d t h _ r mBhsc \�r g ]¯t hk� ]?t e;mic _ c3�­d�c ["\�w mBl ]�w h� _ ["t mBh ]z� h \Zw"]z{V]?t c3d"� ]?\ m�� � r d"d"h \ j�mBl ]j ]z\"] g�h _ g ]� '[ hsg ] � ]?\ m � c \ mBc mBl ]Fw"] m r h tk]?w�� d ] _ h ± _ g ]� '[ hsg ] � ]?\ m � mil ]?\ g ] � r h \���r�{ hkm rVt _ l rVtstk]?\ j ]mBl r m&� ["� m }�]¶["\"w"] g�m r � ]z\«}�]zx c3g ]�rn\ e �i] g�hsc [��¯w�]z{3]zt c3d�� ]z\ m ]�» c3g9m¯h �I}�] j ["\ �

� ]z[ � rV\"\ j r�{3]yr � ] e \ cnm ] m rVt �²h \ YV["\"]Ã^VX3X3X c \ mBl ] g�c ts] c x g ]� '[ hkg ] � ]z\ m �F]?\ j3h \"]z] g�h \ j©h \w"]�{3]?t c3d"h \ j _ g�hkmBh _ rVt�� e � m ] � �?u x c3gDmBl ]µ^VXVX3X«q � � � q�\ m ] g \�r mihsc \"rVt aNc \§x®] g ]z\ _ ] c \ p&]� '[ hkg ] � ]z\ m �� \ j3h \"]?] gih \ j u � l ]�{ h ��[�rVt � r m ] gih rnts�½r g ] c \§�¼t h \�]lfmimid �À¥V¥��I�I� � _ �it � � gihv� _ cV� ¥n\�]?[ � rV\"\R¥ h _ g ]�X3X m rVt � � � �·d � �

��)+( ���"!�!�� $�9�9�� % � ,�-��V��� ��$���� � ��9���)(*�),½���

q�\4w�]z±�\ h \ j ��[ g { h {Vrn} h t hkm�e rn\"w4� c3� ] c x mBl ] g ]� P[ hsg ] � ]z\ m � c \ � l"h _ l4hÂm��Zc � m w�] d ]?\"w"� � ��] _ [§�gihÂm�e u g ]?t h rV} h t hÂm�e u'rV\�w d ] g x c3gi� rV\ _ ] � �5]�� cVgi��d�gihs� r g�h t e x gic3� mBl ] d ] g � d ] _ mBh {V] c x g ]� '[ hkg ] � ]z\ m �mBl r m _ rn\ }�] w"] d ]z\"w�rV}�t e ]z\�x c3g _ ]?w rV\�w�r d"d t h ]?w mic ]?\ l rV\ _ ] mil ] c {3] g rVtkt½� e � m ] � rn\"w \"] m � c3g���i[ g { h {nrV} h t hÂm�e3��#� c }"��] g {3]?wZr m)mBl ]5}�] j3h \"\ h \ j�c x mBl"h � _ l r d�m ] g u3\'[ � ] g�c ["� d"gic3d ] g9mBh ]?� r g ]�\"] _ ]?���Br g9e x c3g)c {3] g rVtst

�i[ g { h {nrV} h t hÂm�e u1� c3� ] c x�� l�h _ l r g ] � c3g�h \©� c3� ] _ rn�i]?� � ] g ]zt e �i]?] � mBc }�] � h \ m ] g w"] d ]z\"w"]z\ m?�� l�hsj3l t eÃc {3] g � hk�­d t h ±"]?w«}�[ m \ c \"] mil ]?tk]?�i� h tstk["� mig r mih {V]��i[ �Z� r g�eyc x r d£c3g9mBhkc \ c x mBl ]��i["} m ]?\�w"]?wg ]� '[ hsg ] � ]?\ m � l"h ] g r g _ lfe�h � j3h {V]?\ h \ ¡ hsj [ g ]¯W � � � � ¿ ] l r�{3]¯� c3� ]z� l r m r g } hkmig r g�h t e�m r � ]z\��i] _ [ g�hkm�e ug ]zt h rV} h t hkm�e u'rV\"w d ] g x cVgi� rV\ _ ]�rV� mBl�g ]?] � r ��c3g5g ]� P[ hsg ] � ]z\ m � mBl r m _ rn\ _ c \ mBg�h }"[ m ] h \ g r mil ] g }"rV� h _�Nr e � mic r _ l"h ]z{ h \ j4l"hkj3l ��tk]z{V]?t&�i[ g { h {nrV} h t hkm�e g ]� '[ hkg ] � ]z\ m � � ~ º#mBl ] g _ c \ _ ] d�m [�rVt�r gig rn\ j ] � ]?\ m �c x mBl ] l"h ] g r g _ lfe r g ]�rVtk� c d£c �i� h }"ts] � q�\ rVw"w hkmBhkc \1u hkmyh �y� c3g9mBl \ cVmBh \ j mBl r mymil ] c {V] g r g _ l"h \ jg ]� '[ hsg ] � ]?\ m x c3g l [ � rV\ �irnx®] m�eZh ��]z{ h w"]?\ m t e r m rV\ ]z{V]?\ l�hsj3l ] g tk]z{V]?t mBl rV\��i[ g { h {nrV} h t hkm�e uf}£] _ rV["��]l [ � rV\��irnx®] m�e m�ePd"h _ rVtkt e w�] d ]?\"w"� c \ c {V] g rVtst&� e � m ] � ��[ g { h {nrV} h t hÂm�e rn\"w cVmil ] g��Zh ��� hsc \§� _ gihkmih _ rVtd"g�c3d ] g�mih ]?� �À�q�\�o§] _ mihsc \ � � ^ � ^��5] c }"��] g {3] mBl r m­mil ] g ]©r g ] � ["t mBhkd ts]y}"[ m _ t c �i]zt e g ]zt|r m ]?w � rV\ h x®]?� m r mBhkc \"�

c xFrT{nr h t|rV} h t hÂm�e3� � l"h � h �µw�] d"h _ m ]zw jVg r d"l�h _ rntst e�h \ ¡ hkj [ g ]²W � ��} e r _ c3�Z�­c \ \ c w"]�~ ����{nr h t �'��i[�} m ]z\"w"]?wbx g�c3� } cVmBl �i] _ [ g�hkm�e rV\"w g ]zt h rn} h t hkm�e u rV\"w+} e r _ c3�Zd r g rV}"ts]Ã\ c w"]µ�i[�} m ]z\"w"]?w�x gic3�d ] g x cVgi� rV\ _ ] � ~ � r _ l \ c w"];w"]z\ cVm ]?w©} e rn\©rV� m ] g�h � � w"]z\ cVm ]?��r g ] _ c \f{3] g�j ]?\ _ ] c x r _ c3�Z�­c \µ�i] m

��_!�?+B&!+B&!3[�?)�+B-�+ �*+ ML�X)���/1>?�Q)*+B/1=a,56 �*�1� O:=21)*�LK� !�1+B%<�A !+B'B'N8Y� >1+B&��1'H3�IL��>@-�,)��V�Q'B��=L35/L��' IA'H30�*�Q)Q#

� �

Page 69: Practical Architectures for Survivable Systems and Networks (Phase

������������� ��������� �������������������� ����� ���"!�� �����#������%$&%')( *�����������+�������,�"-&.'/( �#������������10�����0�����������2�3& '4(& ' (& ' (& ' (& ' (& ' (& ' (& ' (& ' (

������������� 5������������������ 6�����-�����#������� ��7�"8����*2�������"!�� �����#�������2�3&9')( &%')( &%'�(&.':( &.'/( &;'/(& '<( & '4( & '4(& ' ( & ' ( & ' ( �=������������>��">

? ������@BA�����-�@ ����C��� D�E,D�C��� 5"E F"5�EG����C��� ���"!�� �����#�������2H$��������I�+>KJL����� M ')( #��">���2 &"( &9')( M D�E�N�-���C���O�����"����������&%' ')( '�( ':( &9' (�& &%')( 5�E�N"������"@����P#��&.' '/( '/( '4(Q&.' 6"��������@ &;'/( F�5"E�N�������@�������"@����P#���3& R '<( '4( R ��������2 &

7�S ? F��B7�S��OT��"2�@17�S"� ( F�� & ��7������O>�����C���"��>& ��������� ' �+������@ ' ( ��������� & ���"!�� �����#�������2�3& &%' ' �����C@ ' ( && &.' ' ���� ' MVU�� �+-C���">QM& & ' ' ' ' ���C���"�� ������"�W ���C2 T���� W W ���"!�� ����#������C2

&%' ')( � W NX��������">X���#�0�����������2Y�"-,7�S W[Z�Z 3&.' '/( �\M1N,5������������������������ ��-X���C���"������������3& ' '4( � R N,5������������������������ ��-Q>����*���������"�������3

� � Q����S� `�¦Å�� � ��������������� � � � u8�������f�N�<Y � �4d� � �S�:�c� R ���P� � �:���<��V�_K`

�TÅ

Page 70: Practical Architectures for Survivable Systems and Networks (Phase

c x g ]� '[ hsg ] � ]?\ m �Fr _ g�c �i� mil ] mil"g ]z] � r ��c3g�g ]� '[ hkg ] � ]?\ m � �¦� �#t mil"c [ jVl hkm�h ��["�i[�rntst e w"]z� hkg rV}"tk] mic� ]z] d²mBl ]z�i] mBl�g ]?] � rV\ h x®]?� m r mBhkc \"� c xNrT{nr h t|rV} h t hÂm�e ��] d r g r m ]�w"[ gih \ j r g ]� '[ hkg ] � ]z\ m ��� d ] _ h ± _ r mBhkc \rV\"w rV\�rVt e � h �zu hÂmNh � l"hkj3l t e rVw�{nrV\ m r j ] c ["� mBc _ c \"� h w"] gNmBl ] � h \ rV\ h \ m ] j3g r m ]?wZ�½r e w�[ gih \ j � e � m ] �w"]z� hsj \�rn\"w hs�Zd ts] � ]z\ m r mihsc \ � � l ["�zu mil ]Ã� d ] _ h ± _ r mBhkc \ c x mBl ] g ]� '[ hkg ] � ]?\ m � _ rV\ }£]z\"]z± m x gic3�rV\µ["\"w"] g � m rV\"w h \ j­c x mil ]¶�½r e � h \µ� l�h _ lymBl ]Dw h »£] g ]?\ m¯� rn\ h x®]z� m r mBhsc \"� h \ m ] g r _ m � hkmil�c3g w"] d ]z\"wc \ c \"]yrn\ cVmBl ] g?� ¡ [ g�mil ] g��­c3g ]Vu m ] _ l \ h '["]?� mBl r m _ c \ migih }�[ m ] mic��Zc3g ] mBl rn\ c \"] c x mBl ] � r ��c3gg ]� '[ hsg ] � ]?\ m � _ rn\�}�] hs�Zd ts] � ]z\ m ]?w �Zc3g ]�[�\ h x c3g�� t e3�

� ��#$��# �&��Q"��H ��<�� HKL H®S ! ��E�J'3>PO�S¸=�#�y\ cnm ]?w r mÃmil ]²}£] j3h \�\ h \ j4c x aNl r d�m ] g �3u mil ] m ] gi� � � � � � � � � � ��� � � w�]?\ cVm ]?� mBl ] rn} h t hkm�e c x�r_ cV�­d [ m ] g � _ c3�­� ["\ h _ r mBhkc \�� e � m ] � ��}�rn�i]?wµr d�d t h _ r mihsc \ mBc _ c \ mBh \'["]#�ir mBh ��x ePh \ j _ ] g�m r h \ _ gihkmih _ rVt g ]�� '[ hsg ] � ]?\ m �D~®] �·j"� u g ]� P[ hsg ] � ]z\ m �½x c3g �i] _ [ gihÂm�e u g ]?t h rV} h t hkm�e u g ]?rVtÂ� mBhs� ] g ]z� d�c \"� h {3]z\"]?���?u£rV\"w _ cVgig ] _ m �\"]z�i� � h \ mBl ]½x r _ ] c x£rVw�{V] g �i] _ c \�w hkmihsc \"� � � l ]I� _ c3d ] c x£rVw�{V] g � hkm�eF� r e�h \�� cV� ] _ rV�i]z� }£] d"g ] _ h �i]zt ew"]�±�\"]?w�u�}�[ m¯�­c3g ] m�ePd"h _ rVtst e�hÂm&h �I\ cVm �5]?tkt�w"]z±"\"]?w �

o c3� ] c x mil ]¶rVw�{V] g � hkmih ]?� _ rV\y}£]�x cVg ]?��]?]z\«rV�It hs� ]?t e�micZc _?_ [ g u§� hkmBl _ c \"��]� '["]?\ _ ]?� mBl r m _ rV\y}�]d ] g _ ] h {3]?w rV� d�cVm ]?\ mBh rVtst eªl r g�� x®[�t ��mBl ]z�i] _ rV\4}�]­]z\'[ � ] g r m ]?w rn\"w4w"]�±�\"]zw �µº#mBl ] g rVw�{V] g � hkmih ]z�� r e }£]Ãx c3g ]?��]?]?\+rV��["\"t hs� ]?t e u cVg rV��\ cVmZl r�{ h \ j ��] gihkc ["� _ c \"�i]� P[�]?\ _ ]?� mic � c3g�g�e rV} c [ m � cVg� r e \ cVm ]�{3]z\ }�]©rV\ mBh _ hkd r m ]zw�r m rVtkt � q�w"]?rVtst e u¯r d"d�gic3d"g�h r m ]«��[ g { h {nrV} h t hÂm�e � d"g ]?�i] g { h \ j r _ mihsc \��� l�c ["tswÃ}�] m r � ]?\ hsg�g ]z� d ] _ mih {V] c x�� l ] mil ] gImBl ]�rVw�{V] g � hkm�e �NrV�Ix c3g ]?�i]z]?\ c3g \ cnm�� ¨�]zx®]z\"� h {3]�� e � m ] �w"]z� hsj \«rV\�w�w"]�x®]?\"� h {V] d"g�c3j3g r �­�Zh \ j;d"g r _ mBh _ ]?��r g ]D\�] _ ]z�i�ir g�eymBc _ c {V] g#cnmBl ] g � h ��]¶["\�rV\ mBh _ hkd r m ]zw]z{V]?\ m � � ��t mil"c [ j3l�mBl ] g ] _ rn\ _ tk]�r g t e }�] _ hsg _ [ � � m rV\ _ ]?� h \�� l"h _ l � e � m ] � �i[ g { h {nrVt h � \ cVm5d£c �i� h }"ts]� x c3g ]�¢�r �Zd ts]nu�� l ]?\ rVtkt _ cV�­� [�\ h _ r mBhkc \ t h \"]?��rV\�wbrVtkt d£c �5] g r g ] c [ m � � cV� ] g ]?rV� c \�rV}"tk]_ c \ mih \ j ]?\ _ e�d t|rV\���� l"c ["tkw­}�] h \ d t|r _ ]Vuf]�{3]z\ h x h \ mBl ]�tsrV� m g ]?� cVg�m5hkm h � � ] g ]?t e ] � ] g�j ]?\ _ e r _ mihsc \��} e«mil ] c3d ] g r mBhkc \"�#� m rn» � q�\²rVw"w hkmBhkc \1u mBl ];}"t|r � ] h \ _ rV�i]z� c x _ c3�Zd tk] m ] c [ m r j ]?� � r e�g ]?� m � hkmilh \��i[ _ h ]?\ m x c3g ]z� hkj3lfm&h \y� e � m ] � w"]z� hsj \ �

o§[ g { h {nrV} h t hkm�e�h \ mBl�h ���i]?\��i] _ rV\�}�]�w�]z±�\"]zw c \"t e�h \ m ] gi� � c x�� d ] _ h ± _ g ]� P[ hsg ] � ]z\ m � mil r m5� ["� m}�] � ] m [�\"w"] g�h \ _ c3�Zd ts] m ]zt e � d ] _ h ±�]?w _ hkg _ [ � � m rV\ _ ]?�#~®� l ] g ] mBl"c �i] _ hkg _ [ � � m rV\ _ ]?� � r e;d£c ��� h }"t e}�]Dw e \"r �­h _ rVtkt e _ l rV\ j3h \ jf� u�� l"h _ l � h tst c x m ]?\yw h »�] g x gic3� c \"] m�ePd ] c x¾rVw�{V] g � hkm�eÃmic rn\ cVmBl ] g?�

o d ] _ h ± _ �i[ g { h {nrV} h t hkm�e g ]� '[ hkg ] � ]z\ m � m�ePd"h _ rVtkt e {nr g9e _ c \"� h w"] g rV}�t e x gicV� c \"]ªr d"d t h _ r mihsc \ micrV\ cnmBl ] g?� ¡ c3g ]�¢�r �­d ts]Vu c \"]���] m&c x�� e � m ] ��g ]� '[ hsg ] � ]?\ m � �Zhsj3lfm rVtst c � w"] jVg rVw"]zw d ] g x c3g�� rV\ _ ] cVgcVmil ] gIg ]�rVt � mBhk� ]¯w e \�r �Zh _ mig rVw�] c »£� h \ mihs� ]?� c x ]�¢ mig ] � ]�\"]z]?w4~ ] �·j"� u�}£] h \ j rn}"ts] mic�g ]?tsr�¢ _ ] g9m r h \�i] _ [ g�hkm�e²g ]� '[ hsg ] � ]?\ m � h \©x r�{ cVg�c x � r h \ m r h \ h \ j g ]?rVtÂ� mBhk� ] g ]� '[ hkg ] � ]z\ m �D� l ]?\4[�\"w"] g r m�m r _ �§��� ��#\ cVmBl ] g �i] m �ZhsjVl'm�d"gihkc3gihÂmBh�� ] mil ] _ cV�­d [ m r mihsc \�rnt m rn� � �)rV\"w d ] gi�Zhkm w"] j3g rVw�r mihsc \¶r _?_ cVg w h \ j½mBcImBl ]]?� m rV}�t h � l ]?w d"g�hsc3g�hkmBh ]?� � q�\ j ]z\"] g rVtvunr¯� e � m ] � � �¾��[ g { h {Vrn} h t hkm�e�g ]� '[ hkg ] � ]?\ m � �Zhsj3lfm � d ] _ h x e#mBl r m)mBl ]� e � m ] � � ["� m � hkmBl � m rn\"wyr mim r _ � �¶~ d�gic { h w h \ jFh \ m ] j3g�hkm�e rV\"wyr�{nr h tsrV} h t hkm�e rV� d ] _ m � c x���] _ [ gihÂm�e"� rn\"w}�] g ]?� h � m rV\ m¶mBcyl r g w��Nr g ] � rVtkx®[�\ _ mihsc \"��~ d"g�c { h w h \ jÃg ]?t h rV} h t hÂm�e rV\"w l r g w��Nr g ]�x rV["t m�mBc ts] g rV\ _ ] � u� c x m �½r g ] c [ m r j ]z�­~ d"g�c { h w h \ jµg ]z� h � m rn\ _ ] mBcµl r g w��½r g ]�� c3g � c x m �½r g ]�� h \"w"[ _ ]?w4� c x m �Nr g ] _ g rV� l ]?� � urV\"wyr _ m � c x �¶c w²~ ] �Áj�� u�rn\ mih _ hsd r mih \ jDmBl ] _ c \"��]� '["]z\ _ ]z� c x _ c3�­� ["\ h _ r mBhkc \"� h \ m ] g x®] g ]?\ _ ]Vu�³ c§c w"�?u]�r g�mBl P["r � ]z�?u¾t hsj3lfm \ h \ j � mBg�hs� ]?�?u)rV\�w d�c �N] g x r h ts[ g ]?� �¯mBl r m¶�­hkj3lfm�cVmil ] g � h ��] g ]?\"w�] g�mBl ]�� e � m ] �_ cV�­d tk] m ]?t eµc3g�d r g�mih rVtkt eyh \ c3d ] g r mih {V] � q�\ mBl"h � _ c \ m ]�¢ m u��i[ g { h {nrV} h t hÂm�e r d"d ]?r g � h \ mBl ] j [ h ��] c x5rl"hkj3l ��tsr e ] g � e � m ] � h \ m ] j3gihÂm�e g ]� '[ hsg ] � ]?\ m��D _!�?+B&a35�1�1)*,L35%<� "35& �<35;��/ +B/ �*�1�@���Q%�21)*� E 'B�1�:3P� �N,)*� � � � � � K 35/ �#� &$�1)*,��*��%W�[�*�:30�[)���>1��&�+B=/1��> 3P)��Q35' !(�*+B-��a&�I?&�����-��QBL��/1&*��/�] &

E �-�FUF49>9���1)�,�����%W� � � � � � ( �*,�+B/1%�'B21>1� -�21' ��+B'B�WML��'N&���%�21)�+ �JIA35/1>.��,��Y��)�-�+ �F>�I?/:35-�+B%V��)�35>1��, ��&!��,[�Q/?&�21)*� �N��)�67,)*-435/1%��L#

� �

Page 71: Practical Architectures for Survivable Systems and Networks (Phase

� l ["�?u��5]DrVw c3d�m&mil ]�x c tst c � h \ j;m ]?\ m r mih {V]¶� c3g��Ph \ j w"]z±"\ hkmihsc \"�z�

� $ J �¼ERQ � <�S¸H®E£J�= ��Q ��H ��<��¾H L H®S ! g ]?tsr m ]z� mBc�mBl ]¶]�¢ m ]?\ m&mBc � l"h _ l ��[ hkm rV}"t e _ c3g�g ] _ m rV\"wµ[ d � mBc �w"r m ] h \§x c3gi� r mBhkc \ _ rV\�}�]Dr�{Vr h t|rn}"ts]¯� l ]?\"]�{3] g�hkm&h �I\"]?]zw"]?w � q�\�x c3gi� r mihsc \Ã��[ g { h {nrV} h t hÂm�e�h �&r� ]�rn\ h \ j x®["t _ c \ _ ] d�m r m w h »£] g ]?\ m t|r e ] g � c x rV}"� mig r _ mBhkc \1u h \ _ tk["w h \ j � e � m ] � �?uR\"] m � c3g�� �zu�rn\"wr d"d t h _ r mihsc \�� �

� ��E��4O ��S�>PQ�@B= !�=zS�> � = �)Q"��H��"< �¾H LKH S ! g ]?tsr m ]z� mBc;mil ]�]�¢ m ]?\ mImBc � l"h _ l r _ c3�Zd [ m ] g � e � m ] � � �rn} h t hkm�e _ rn\ _ c \ mBh \'["] mic �Br mih ��x e _ ] g�m r h \©� m r m ]zw g ]� '[ hkg ] � ]?\ m � h \ mBl ]Fx r _ ] c xNr g } hkmBg r g�e rVw§�{V] g � hkmih ]z� �

� µ>fS�C;ERQ � = �)Q"��H��"< �¾H LKH S ! g ]?tsr m ]z� mic«mBl ]­]�¢ m ]z\ m�mBc � l�h _ l r _ c3�­d [ m ] g \"] m � c3g���� ��rV} h t hÂm�e_ rV\ _ c \ mih \'["] mBc �Br mih �9x e _ ] g�m r h \µ� m r m ]zw g ]� '[ hsg ] � ]?\ m � h \ mil ]�x r _ ] c x¾r g } hkmig r g9e rVw§{3] g � hÂmBh ]z� �

� O)O LKH�3<�S¸H®E�Jµ=z>PQ"��H�3>�= �)Q"��H��"< �¾H LKH S ! g ]zt|r m ]?� mBc&mBl ]�]�¢ m ]?\ m mBc � l"h _ l¶mBl ]��i] g { h _ ]?� d"gic { h w�]?w} e rn\�]z\ mihsg ]�� e � m ] � r d"d t h _ r mBhkc \Ãr m�m r h \Ã� e � m ] � �i[ g { h {nrV} h t hkm�eV�

� � J£ST>'Q¸O Q�H =?>Ã= ��Q"��H ��<�� HKL H®S ! g ]zt|r m ]?� mic;mBl ]#]�¢ m ]z\ mImic � l"h _ l rn\ c {3] g rVtst£]?\ m ] gid"g�h ��]Z~ �i[ _ l rn�rD}"["� h \"]z�i� c3g _ gihÂmBh _ rVt h \�x g rV� mBg [ _ m [ g ] � _ rV\ _ c \ mBh \'["] mBc �Br mih ��x e _ ] g�m r h \­� m r m ]zw g ]� '[ hkg ] � ]z\ m �h \ mBl ]�x r _ ] c x r g } hÂmBg r g�e rnw�{3] g � hÂmBh ]?� �

o e � m ] � �i[ g { h {nrV} h t hkm�e _ rV\Ã}�]�w"]z±"\"]?w h \ m ] g�� � c x)rV\ c {3] g rVtkt�r d"d t h _ r mihsc \ c3g � d ] _ h ± _ ��] g { h _ ]?�zuc3g�h \ m ] gi� � c x�� d ] _ h ± _µ_ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mBhsc \ � e � m ] � �?u½��["}"� e � m ] � �zu c3g \"] m � c3g�� � � � r _ lm�ePd ] c x d£cnm ]?\ mih rVt�rVw�{3] g � hkm�ey� r e l r�{3] hkm � c �&\ � ]?rV�i[ g ] c x �i[ g { h {nrV} h t hkm�eV�q�\ mBl ]�w"]�±�\ hkmihsc \��¶rV} c {V]Vu mBl ] m ] gi� �ir g } hÂmBg r g�e rVw�{3] g � hkmBh ]?� ��hk�­d t h ]z� �Zc3g ] mil rV\ � ] g ]?t eªmBl ]

rV} h t hÂm�eZmic � hÂmBl � m rV\�w � � \ c �&\«rVw�{V] g � hkmih ]?� �­cVg ��� d ] _ h ±�]zw«rVw§{3] g � hÂmBh ]z� � � hkm rnts� c�hk�­d t h ]z�½r _ l r g �r _ m ] g�h�� r mBhkc \ c x mBl ]�rn} h t hkm�eÃmBc � hÂmBl � m rV\"w�rVw§{3] g � hÂmBh ]z� mBl r m �N] g ]�\ cVm rn\ mih _ hsd r m ]?w©��[ _ l rn� mBl"c ��]mBl r m ]�¢ _ ]?]zw mBl ] g ]?t h rV} h t hÂm�e rn\"w �i] _ [ g�hkm�e�mBc ts] g rV\ _ ]?�N��[ d"d�c �i]zw"t e _ c {V] g ]zwÃ} e­mil ]#w"]z� hkj \ � q�\ ]?r _ l_ rn�i]Vu'r � ]�rn\ h \ j x®["t�rn�i�i]z�i� � ]z\ m5c xR��[ g { h {nrV} h t hÂm�eDg ]?� m ��\ cnm�c \"t e;c \F� l r m�l r d�d ]z\"� � l ]?\­rV\�rV\ mih _ �hsd r m ]zw�rVw§{3] g � hÂm�e�c _z_ [ g �?u�}�[ m rVts� c�c \�� l r m��Zhsj3lfm l r d"d ]z\ h \ g ]?� d�c \"��] mic ["\"rV\ mBh _ hsd r m ]?wZ]z{V]?\ m � �� l"h � g ]� '[ hkg ]?� � c3� ]Iw�] m ] gi�Zh \�r mBhsc \ c x mBl ]¯r _ m [�rVt _ c {3] g r j ]nu§\ cVm � ["� m mil ]&w"]?� hsj \"]zw _ c {3] g r j ]I� hkmilg ]z� d ] _ m�mic rn\ mih _ hsd r m ]?wÃx rV["t m �&rV\�w mil"g ]?r m � �

aNc \ mBh \'["]?w©]z\�x c3g _ ] � ]?\ m¶c x�� e � m ] � h \ m ] j3gihÂm�e u�� e � m ] � r�{nr h tsrV} h t hkm�e u�w�r m r _ c \�±�w�]?\ mBh rVt hÂm�e u1rn\"ww�r m r h \ m ] j3g�hkm�e ~®x cVg ]�¢"r �­d tk] � r g ] m�e§d�h _ rntst e x®["\"w�r � ]?\ m rVtNrn� d ] _ m � c x&��[ g { h {nrV} h t hÂm�e3�ÿ�l ]z\"]z{V] g� d ] _ h ± _ t c �5] g ��t|r e ] g �i[ g { h {nrV} h t hkm�e«d"gic3d ] g9mBh ]?��r g ]�]�¢ d t h _ hkm t eªh \ _ tk["w"]?w4r �Zc \ jÃmBl ] hsg _ c \"� mihkm [�]?\ m� e � m ] � �i] _ [ g�hkm�e�d"gic3d ] g9mBh ]?�?u mBl ]z\©�i[ g { h {nrV} h t hkm�e _ rV\©rnts� c }£] _ c \"� h w"] g ]zw²rV��r���] _ [ gihÂm�e«d"g�c3d ] g�m�e~Krn\"w1u1� d ] _ h ± _ rVtkt e u�rV\ h \ m ] j3g�hkm�e�d"gic3d ] g9m�e���� ( c �N]�{3] g u�x c3g�d"g ]?��]?\ mDd [ gid�c ��]?���5] _ c \"� h w"] g r d"d t h �_ r mBhsc \«�i] g { h _ ];��[ g { h {nrV} h t hÂm�e rV�#rV\ c {3] g r g _ l"h \ j d"gicVd ] g�m�eµmBc }�] � r h \ m r h \"]?wµ} e�mil ]Fr d�d t h _ r mihsc \h \ hÂm �I]?\ mihsg ] m�e3�

� ��#$� � �1>����QnH S !q�\ m [ hÂmBh {3]?t e u mil ]�\"r m [ g rVtÂ�¼t|rV\ j [�r j ] � ]?rV\ h \ j­c x¾�i] _ [ g�hkm�eyhs�Zd t h ]?� d"gicVm ] _ mBhsc \ªr j r h \"� m ["\"w"]z� hsg rV}"tk]]z{V]?\ m � � o e � m ] � �i] _ [ gihÂm�e rV\"w²w�r m rÃ�i] _ [ g�hkm�e r g ] m � cym�ePd ]z� c xN��] _ [ gihkm�eV� � l ] mBl"g ]?] �Zc � m _ c3� ��Zc \"t e�h w"]?\ mih ±�]zw d"gicVd ] g�mBh ]?� g ]?tsr mBh \ j¶mBc ��] _ [ gihÂm�e r g ] _ c \�±�w"]z\ mBh rnt hkm�e u h \ m ] jVgihkm�e u�rn\"wÃr�{nr h tsrV} h t hkm�eV�� l ] g ] r g ]­rVts� c«cVmil ] gDhs�Zd£cVg�m rn\ m x cVgi� � c xN�i] _ [ g�hkm�e u¾�i[ _ l rV� mBl ]­w"] m ] _ mBhkc \ c x �­h �i["��]�rn\"w mBl ]

��`

Page 72: Practical Architectures for Survivable Systems and Networks (Phase

d"g ]z{3]z\ mBhsc \ c x j ]?\"] g rVt �­h �i["��] mBl r m w c ]?�F\ cVm \"] _ ]?���Br g�h t e { hsc tsr m ] _ c \�±�w"]z\ mih rVt hkm�e u h \ m ] j3gihÂm�e u cVgr�{nr h tsrV} h t hkm�e u d r g�mih _ [�t|r g t e � l ]?\ _ c3�Z�Zhkmim ]?w } e rV[ mBl"c3g�h�� ]?wy["�i] g � �¿�hkmil g ]z� d ] _ mZmBc rV\ e d r g�mih _ [�t|r g x®[�\ _ mihsc \�rnt½t|r e ] g u mBl ] d"g�hs� r g�e r m�mBgih }"[ m ]?� c x��i] _ [ g�hkm�e r g ]

�i[ �­� r gih�� ]zwyrV�Ix c tst c �&�z�� ��E�J � %�>PJ£S¸H®<�LKH S ! � aNc \�±�w"]z\ mBh rnt hkm�eFh \f{ c tÂ{3]z� d"g�cVm ] _ mBhkc \­r j r h \"� m ["\"w�]?� hkg ]zw g ]zts]�rn�i] c x h \§x c3g �� r mihsc \Ã} eymBl ] g ]zts]?rV�i] g u£rV\"w d"gicVm ] _ mBhsc \ªr j r h \"� m ["\"w"]z� hsg ]?w©r _ '[ h � hkmihsc \ c x h \�x c3g�� r mBhsc \Ã} emil ]�r _ '[ hkg ] gz��aNc \�±�w"]z\ mBh rnt hkm�e h � � ]?rV\ h \ j x®["t1� hkmil«g ]?� d ] _ m�mBc w�r m r�uR}"[ m rVts� c � hkmil«g ]?� d ] _ mmic mBl ]�� e � m ] �/hkm �i]?tÂxu�x c3g ]�¢�r �­d ts]Vu � r h \ m r h \ h \ jZmBl ] _ c \�±�w�]?\ mBh rVt hÂm�e«c x�� c x m �½r g ] c3g�c x mBl ]l r g w��Nr g ] hk�­d ts] � ]?\ m r mBhkc \ �

� $ J£ST>�RQ�H®S ! � q�\ m ] j3gihÂm�e«hk�­d t h ]z� g ] � r h \ h \ jZh \©r­� c ["\�w1u�["\ hk�­d r hsg ]zw1u c3g#cnmBl ] g � h ��]�w"]?� hsg rV}"ts]_ c \"w hÂmBhkc \ � q�\ m ] j3g�hkm�e�h � � ]?rV\ h \ j x®["t h \ � rV\ e �Nr e � ��hÂm � r eFl rT{V]#� c3� ]�� l r m w h »�] g ]?\ m�� ]�rV\§�h \ j �Ix c3g r­� e � m ] � u£r­��["}"� e � m ] � u�rV\«r d"d t h _ r mBhkc \1u"w�r m r�u l r g w��Nr g ]nu _ c3�­� ["\ h _ r mBhkc \"�&t h \ � �?urn\"w cVmBl ] g ]?\ mBhÂmBh ]z� �

� ��<�H L <�� H LKH S ! � ��{nr h t|rV} h t hÂm�e«hk�­d t h ]z� mBl r m _ ] g�m r h \ g ]� '[ hkg ]?w g ]?� c [ g _ ]?��r g ] r�{nr h tsrV}"tk]�� l ]?\rn\"w+rn�­\"]z]?w"]zw � ��{nr h t|rV} h t hÂm�e _ rV\�}£]�r d"d t h ]zw�r m­� rV\ e ts]�{3]zts� c x�rV}�� mBg r _ mihsc \�u h \ _ ts[�w h \ j� e � m ] � �zu1�i[�}"� e � m ] � �?u�w�r m r�]z\ mihkmih ]?�zu�rn\"w _ c3�Z� ["\ h _ r mBhsc \"�&t h \ � � � � g ]�{3]z\ mihsc \ c x w"]?\ h rVt c x��] g { h _ ] h �)rV\Fr�{nr h t|rV} h t hÂm�e#g ]� '[ hsg ] � ]?\ m uVrVt mil"c [ jVl�hÂm rnts� c¯l rV�¾r�� e � m ] � � h \ m ] j3gihÂm�e _ c3�Zd£c \"]?\ m��

� ��S¸:�>PJ£S¸H�3<�S¸H®E£J � �#[ mBl ]z\ mih _ r mBhkc \F]?\ _ c3�Zd rV���i]?��w�] m ] gi�Zh \�r mBhsc \ mBl r m r d"g ]?��[ � ]zw h w"]z\ mihkm�e~ c x r�["�i] g uR� e � m ] � u��i["}�� e � m ] � u c3gIcnmBl ] g _ c3�Zd [ m r mBhkc \�rVt�rV}"� mig r _ mBhkc \ �5h �&r _ m [�rVtst e {nrVt h w � q ml rV� � rV\ e x c3gi� �?uP�i[ _ l rV�Nrn[ mBl ]z\ mBh _ r mBh \ j rD["�i] g } e r�� e � m ] � u�rV[ mBl ]z\ mih _ r mBh \ j r�� e � m ] � } ern\ cVmBl ] g � e � m ] � u"rV[ mBl ]?\ mBh _ r mih \ j r;� e � m ] � } e r;["��] g ~®] �·j"� u mBc ]?\"��[ g ] mil ]�["��] g½h �N\ cnm }�] h \ j� d£cPc x®]zwµ} e r�} c3j ["�I� e � m ] � ���

� A5Q �)=zST>�%4O)<�S¸:)= � q�\ _ c \'{V]?\ mBhkc \�rVt�� e � m ] � �?u�rD[��i] g�l rV��\ cDg ]?rVtRrV�i��[ g rn\ _ ] mBl r m�l ] c3g � l ] h �r _ m ["rVtst e _ c3�­� ["\ h _ r mBh \ j � hÂmBl�mBl ]&w"]z� hkg ]?wZ� e � m ] � ~ g r mil ] g�mBl rV\Zr � rV� '["] g rVw�] g c3g � gic�� rV\P�l�c3g ��]?wª� e � m ] � � u�rV\"w c \"];� e � m ] � l rV�#t hkm�m tk]¶rV�i��[ g rV\ _ ] mBl r m#hÂm#h ��r _ m [�rntst e _ c3�Z� ["\ h _ r mih \ j� hÂmBl r#�i] _ c \"w�� e � m ] � c x hÂm � _ l"c3h _ ]¶~ g r mBl ] g mil rV\�r � rV� '["] g rVw"] g¾c3g r _z_ h w"]?\ m rnt"rVt m ] g \�r mih {3] ���� _ c3�Z� ["\ h _ r mihsc \ d r mBl � l"c ��] m ] g��­h \�r mBhkc \"� _ rV\D}£] rn�i�i[ g ]?wD� hkmil"c [ m _ c3�­d�gic3�Zh ��] h � � \ c �&\rn��r �� � ��� ��� � � � ~Krnt mBl�c [ j3l rn� h � c x m ]?\ mil ] _ rV�i] h \ º�g rV\ j ] ´NcPc3��d r g tsrV\ _ ] c x mBg ["� m u3� l r m�h �g ]�rVtkt e�� ]?rV\ m h � r �� � ��� � � � �& � � � �& V��� � g [�� m ]zw d r mBl � � ["� m }£] d ] g � h � m ]z\ m rV���5]?tst"rV� h \ hÂmBh rntst ern[ mBl ]z\ mBh _ r m ]zw ��º#mil ] g g�h � � � h \ _ ts["w"] _ c {3] g�m _ l rn\"\"]?tk� rV\"w mihs�Zh \ j r mim r _ � � g ]zt|r m ]?w mic#mBg ["� m ]?wd r mBl ��~®] �·j"� u���]?] ¹ Wf n� Ä|���

� 8DQ¸>��£>PJ£STH E�J E�� �4HK= �)=?> � �#} c {V]yrV\"w }�] eVc \"w ]�¢ d t h _ hkm { hkc t|r mBhsc \"� c x _ c \§±�w"]?\ mih rVt hkm�e u h \§�m ] j3g�hkm�e u�r�{Vr h t|rn} h t hkm�e uPrV\�w«rV[ mBl ]z\ mih _ r mBhkc \ d£c t h _ h ]z�?u mil ] g ] _ rV\µ}£] �Zh �i[��i]?� mil r m r g ]D[�\"w"]?� hsg �rn}"ts]�}"[ mImBl r m w c \ cVm ]�¢ d t h _ hÂm t e { hsc t|r m ] mBl�c �i] d�c t h _ e ]?tk] � ]?\ m � � �i[ _ l rV� _ c {V] g�m _ l rn\"\"]?tk�rn\"w�� � rVtst ��� _ rVts] mBl ]zx m � c x;��] g { h _ ]?�zu�� cV� ] c x�� l"h _ l�� r e }�] mBcPc � � rVtkt mBc }�]©w"] m ] _ m ]zw �� g ]z{3]z\ mBhsc \ c x �Zh �i[��i]¶]?\ _ c3�Zd rV�i��]?� mBl"c �i] �

� A5< �4O�>'Q¸O Q¸E1E �¾J'� <�J'% <�J£STH @iQ¸>��>'Q�=?>3@B>PJ ��HKJ�>'>PQ�H J'�0ST>��: J)H ���)>P= � � r �­d ] g�d"gicPc ±�\ j²h �rn\4rV� d ] _ m;c x h \ m ] j3g�hkm�eªmil r m�h � d r g9mBh _ ["tsr g t e _ g�hkmih _ rnt¾� hkmil4g ]z� d ] _ m;mBcymBl ]­��] _ [ gihkm�e�� ] _ l r¸�\ h � � � mBl ] � �i]?tÂ{3]z�?u£rV\"wµ]?� d ] _ h rVtkt e x c3g _ g�ePd�mic3j3g r d"l"h _ hk�­d ts] � ]?\ m r mBhkc \"� � � ] _ l rn\ h � � � mBl r m��] g�hsc ["��t e�hs�Zd ]?w"] g ]z{V] g �i]y]?\ jVh \"]z] gih \ j _ rn\ rVts� c }£] hs�Zd£c3g9m rV\ mDmBc ��] _ [ gihÂm�e u h \ mil r m;mil ] g ]

� �

Page 73: Practical Architectures for Survivable Systems and Networks (Phase

h ��rVtÂ�½r e �DrV\ ]zts] � ]z\ m¶c xN��] _ [ gihkm�e } e²c }"� _ [ gihÂm�e � d r g9mBh _ ["t|r g t eµh \�� c x m �Nr g ]�� hs�Zd tk] � ]?\ m ]zw_ g�ePd�mic3j3g r d"lfe3� � ] _ l \ h '["]?��x c3g _ c w"]ÃrV\"w w"r m r c }�x®["� _ r mBhkc \ _ rV\ }£]Z{nrVts[�rn}"ts]�x c3g;� r �'h \ jhÂm w h _ ["t m#mic g ]�{3] g �i]���]?\ j3h \"]z] g¶c } � ] _ m _ c w�]�rV\"w mic t c _ r m ] _ gihkmih _ rVt�w�r m r ]zts] � ]z\ m ���i[ _ l rn�_ g�ePd�mic3j3g r d"l"h _ � ] ePh \ j­h \�x c3gi� r mihsc \ �

� �'%)H®ST< �¾H LKH S !b<�J'% %�>'S�> VSTH E�J E � � H = � =z> � ¡ c3g�mBl ]�rV} c {V]�� � ]?\ mihsc \"]zw m�e§d ]?� c x �Zh �i[��i]Vurn\"w d r g�mBh _ ["tsr g t e x cVg5�Zh ��["�i]¯} e r d"d r g ]?\ m t e rV[ mil"c3gih�� ]zw�["��] g ��~®� l"c;� r e r _ m [�rntst e }£]¯] hÂmBl ] gtk] j3hÂmBhk� r m ]�[��i] g � cVgI� rV� '["] g rVw"] g � � u�]�» cVg�m � � [�� m }�] � rVw"] mic w�] m ] _ m �i[ _ l«�Zh �i[��i] �

q�w"]z\ mih ± _ r mBhkc \ rn\"w rV[ mil ]?\ mih _ r mBhsc \ r g ]�]?���i]z\ mih rVt mBc«mil ]�]z\�x c3g _ ] � ]?\ m�c x _ c \§±�w"]?\ mih rVt hkm�e u h \§�m ] j3gihÂm�e u r�{Vr h t|rn} h t hkm�e u1rV\"w d�g ]z{V]?\ mBhkc \ c x j ]?\�] g rnt h�� ]?w �­h �i["��]Vu rV�D�5]?tktNrn� mic�� ]�rV\ h \ j x®[�t �­h �i["��]w"] m ] _ mBhkc \ � � l ] ey� r e }�]D] hkmil ] g ]�¢ d t h _ hkm t e w"]?� hsj \�r m ]?w�rV�&� e � m ] � ��] _ [ gihkm�eyg ]� '[ hkg ] � ]?\ m � cVg ]zts��]�i[�} � [ j r m ]?w mBc�mBl ] hk�­d tk] � ]?\ m r mBhsc \1u§}�[ m r g ]�x®["\�w�r � ]?\ m rVt h \Ã] hÂmBl ] g _ rV�i] �

� rV\�w�r mBcVg�eDd£c t h _ h ]z�1x c3g _ c \�±�w�]?\ mBh rVt hÂm�e ~ ] �·j"� u � ["t mBh ts]z{V]?tf��] _ [ gihkm�e�� u h \ m ] j3gihÂm�e uVrT{nr h t|rV} h t hÂm�e uTrn\"w�i[ g { h {nrV} h t hÂm�e ~ � �)o£u � ��q u � ���;u§rV\"w � � � u�rn� h \ migic w"[ _ ]zw h \Ão§] _ mBhkc \«� � ^ ��l r�{3] mBl ]#rVw�{nrV\ m r j ]mBl r m�mBl ] e _ rn\"\ cVm }�]F{ hsc tsr m ]zw©} e ["�i] g r _ mihsc \"�Z~ rV�i��[ �Zh \ j mil r m�mBl ] � ] _ l rV\ h � � �¶r g ] _ c3gig ] _ m t ehs�Zd tk] � ]?\ m ]zw � u }"[ m�l r�{V] mBl ] w h �Brnw�{nrV\ m r j ] mBl r m;mBl ] e � r e }£] h \�³�]�¢ h }"ts]�x c3g _ ] g9m r h \ �'h \"w"� c xr d"d t h _ r mBhkc \"� �ú \ mil ] cVmil ] gDl rV\�w1u mil r m�h \�³�]�¢ h } h t hkm�e«h � d"g ] _ h �i]zt e � l r m�� r � ]?� mBl ] � d£c �5] g x®[�tc3g�j rV\ h��?h \ j r g _ l�hkm ] _ m [ g rVt _ c \ _ ] d�m � �

aNc {3] g�m _ l rV\"\�]?ts�#~ c [ m � c x|��}�rn\"w�� hkj \�rVt h \ j�d r mBl � � g ] d�g ]?��]?\ m5d£cVm ]?\ mBh rVt"t c �i��]?� c x _ c \�±"w"]?\ mBh rVt hÂm�e3�� l ] e r g ]�r d"g�c }"ts] � d"g�hs� r gih t eyh \ � ["t mih ts]�{3]ztÂ����] _ [ g ]F� e � m ] � �zu h \©� l"h _ l�hkm�� r e }�] d£c ��� h }"ts] mic� hkj \�rVt h \�x c3g�� r mihsc \ mBl"g�c [ j3l�h \�x®] g ]?\ _ ] _ l rV\"\"]zts� mBc t c �5] g ts]z{V]?tk�?u h \ { hkc t|r mihsc \ c x mBl ]���] _ [ gihkm�ed�c t h _ e3� ( c �5]z{V] g u _ c {3] g�m _ l rV\"\"]zts��r g ] c x m ]?\«\ cVm ]�¢ d t h _ hÂm t e rVw"w g ]?���i]?w«} e � e � m ] � ��] _ [ gihÂm�e�d�c t h �_ h ]?�zu�rV\"w r g ] m�ePd"h _ rVtkt e \ cVm¶d"g ]z{V]?\ m ]zw } e _ c \f{V]?\ mBhkc \�rVt���] _ [ gihkm�e r _?_ ]?�i� _ c \ migic tk�?� mil ] e } ePd rn�i�_ c \'{V]?\ mBhkc \�rVt _ c \ mBgic ts�¶rVt mBc3j ] mBl ] g�g r mil ] g�mil rV\²{ hkc t|r mBh \ j�mBl ] ��� �¯{ c3h w�rV\ _ ] c x _ c {V] g9m _ l rn\"\"]?tk�h �¯r d"gic }"ts] � mBl r m�� ["� m }�]�rnw"w g ]z�i��]?wªw"[ gih \ j � e � m ] � w�]?� hkj \1u hs�Zd tk] � ]?\ m r mihsc \�u�rV\�w c3d ] g r mBhkc \ �¨�] m ] _ mBhsc \ c x _ c {3] g9m _ l rV\"\"]zt�]�¢ d t cVhkm r mBhsc \ h �&r d"g�c }"ts] � mil r m&� ["� m }£]¶rnw"w g ]z�i��]?w«w�[ gih \ j�c3d ] g r��mBhkc \«~ �i]z] � g�c _ mBc3g rV\"w � ]?[ � rV\�\ ¹ W��TX Ä|��� � � c;m�ePd ]?� c x _ c {V] g9m _ l rV\�\"]?tk�Nr g ] g ] _ c3j \ h�� ]?w�� � mic3g r j ]_ l rV\�\"]?tk�D~®� l"h _ l ]�¢ d t cVhkmNmil ]�� l r gih \ jFc x g ]?� c [ g _ ]?�&r _ gic ��� � ["t mihsd tk]&�i] _ [ gihÂm�e tk]z{3]zts�½[�� h \ j \ c3gi� rVt� e � m ] � x®["\ _ mihsc \�� h \ ["\'["��[�rVt½�Nr e � � uNrV\"w mBhk�­h \ j _ l rV\"\"]zts�µ~®� l�h _ l ]�¢ d t c3hkm�mBl ] mihs� ]�����]?\"� hkmih {3]}�] l r�{ hsc3g&c x¾r�� e � m ] � u d ] g�l r d �¯} eyc }"��] g { h \ jZmil ] g ]�rntÂ� mihs� ]#}�] l r�{ hscVg¯c x r�� _ l ]zw"["tk] g ���½´ ] _ rV[��i]�Zc � m ]�¢ h � mBh \ j � e � m ] � �#� mBh tkt l r�{3] c {3] g9m t e ]�¢ d t cVhkm rn}"ts]���] _ [ gihÂm�e ³�rT�&�zu _ c {3] g9m _ l rV\"\"]zts��r g ] c x m ]z\c x�tk]?��� h \ m ] g ]?� m?� ( c �5]z{3] g u h \ l�hsj3l t e _ g�hkmih _ rnt�r d"d t h _ r mBhsc \"�?u mil ] e _ c ["tsw�}£]�rV\ hs�Zd£c3g9m rV\ m � c [ g _ ]c x�� e � m ] � _ c3�Zd"gicV�­h �i]Vu�x c3g ]�¢"r �­d tk]Vu�� hÂmBl©mBl ]�r h w c xNr � gic � rV\ l"c3g ��] mBl r m�h � �Zc w"["t|r mBh \ j­mBl ]_ c {V] g�m _ l rV\�\"]?t � �� ["��]zx®["t d r d ] g } e � h tstk]?\ ¹ ^§�TX Ä �i[ �Z� r gih�� ]?��^nX e ]�r g � c x �Zc w�]?t h \ j rn\"w+rn\�rVt e � h � c x � �)o

_ c {V] g�m _ l rV\"\"]zts� �¶aNc {3] g9m _ l rV\"\�]?ts� _ rV\©rnts� c ]�¢ h � m � hkmilªg ]z� d ] _ m�mBc � ��q u � ���;u�rV\"w � � � u�}"[ mmBl ] e ��]?] � tk]?���¯]?rV� eÃmic�h w"]z\ mih x e rV\"wµ]�¢ d t cVhkm��� m ]?r _ l t|r e ] g�c x5rV}"� mBg r _ mBhkc \1u£]�r _ l²c x mil ]?��] _ c \ _ ] d�m � � r e�l r�{3] hkm � c �&\ h \ m ] gid"g ] m r mBhsc \1u h \

m ] gi� � c x mil ]DrV}"� mBg r _ mBhkc \"�&r mImil r m t|r e ] g?�� l"g ]�r m � mic �i] _ [ gihÂm�e r g ] _ c \"� h w"] g ]?w h \�o§] _ mBhkc \�^ � � �� E ' �*�1,21=� +B-��1'B+B%Q30�*+B,/1&�,56!%�,�ML��)��a%<�:35/?/1��'B&a+B/ -[2?' ��+B'B�WML��' !J&���%�21)*��&*I�&*�*�Q-�& �:3�ML�A8Y����/ >1,� !/1�1'H3�IL��> +B/ ���?+B&[)����Y,)*�QK`&*I�&*�*��- 35/1>

/1�W�J F,)*;[35)*%<�1+ �*�Q%W�*21)���&`���:30� &*I�&*�*��-�+B%Q35'B' I &�����; �*, 3�ML,+B>[%�,�ML��)*� %<�:35/?/1��'B&X���L# =1#BK5&����-C )�,�%W��,)`35/1>@>V��21-435/1/ � � � � � (T-43QI$�:3�ML�!&*+B=/1+ O:%Q35/L�8Y��/1�WO1��&!67,)",5�*�1��)V)*��C�21+B)*��-��Q/L�*&V35&" F��'B'(K18Y��%Q3521&�� �*�1� �:35)���+B,/1+B/?=a)���C�21+B)���>G%Q35/A%Q,/L�*)�+B812?�*�$��,a+B/?%Q)*�Q35&���>G&*21)*M�+ M3581+B'B+ �JIL#

� �

Page 74: Practical Architectures for Survivable Systems and Networks (Phase

� ��#$� � M >PLKH®<�� HKL H®S !4<�J % G�< �)L S�A5E£L®>'Q¸<�J 3>� rV\ e�g ]� '[ hkg ] � ]?\ m ��x cVg1g ]zt h rn} h t hkm�e rV\�w¶x rn["t m1mic ts] g rV\ _ ]�r g ] r d"d"g�c3d"g�h r m ] h \¶rVw�w g ]z�i� h \ jImBl ]�{nr g�hsc ["�m�ePd ]z� c x mBl"g ]�r m � mic�g ]?t h rV} h t hkm�e ��[ �­� r g�h�� ]zw h \ oP] _ mihsc \ ^ � ^ rn\"w � rV}"tk] ^ � ^ � � c � m�c x mil ]?��]g ]zt h rV} h t hkm�e�g ]� P[ hsg ] � ]z\ m � _ rV\ l r�{V] � r ��c3g�hs�Zd t h _ r mihsc \"� c \ � e � m ] � rV\�w \"] m � c3g�� ��[ g { h {nrV} h t hÂm�e u h \l r g w��Nr g ]nu � e � m ] � � c x m �Nr g ]Vu \"] m � cVgi� � c x m �Nr g ]nu�rV\"w r d"d t h _ r mBhsc \©� c x m �Nr g ] � q�\ mBl ]­rV}"��]?\ _ ] c x�i] gihkc ["�I]z» c3g9m �&r mIj ]?\"] g rVt h�� ]zwÃw"] d ]?\�w"]?\ _ ]Vu mBl ]�x r h tk[ g ] c x r _ c3�Zd£c \�]?\ mI� r e­m�ePd"h _ rVtst e­g ]?��["t m&h \mBl ]¶x r h ts[ g ] c x l"hkj3l ] g ��tsr e ] g _ c3�­d�c \"]z\ m � mBl r m w"] d ]?\"w c \ mBl ]�x r h ts]zw _ c3�Zd£c \"]?\ m��

o c3� ] c x mBl ] g ]?t h rV} h t hÂm�e _ c \ _ ] d�m �µr g ] _ t c �i]zt e mBh ]?w mic3j ] mil ] g � hkmBl �i] _ [ gihÂm�e _ c \ _ ] d�m � � ¡ c3g]�¢�r �Zd tk]Vu g ]?t h rV}�t e�l"hkj3l r�{nr h t|rV} h t hÂm�e � hÂmBl g ]?� d ] _ m½mBc � e � m ] � �IrV\"w \�] m � c3gi� � h � _ t c �i]zt eZg ]zt|r m ]?w micmBl ] d"g ]z{3]z\ mBhsc \ c xIw"]z\ h rnts� c xI��] g { h _ ] � �#tk� c u)w"] j3g rVw�]?w d ] g x c3gi� rV\ _ ] �Zc w�]?��r g ] _ t c �i]zt e t h \ � ]zw� hkmil x rV["t mImic ts] g rV\ _ ]¶rV\"w g ]?� d�c \"��]?� mBc w"] m ] _ m ]?w«rV\ c3� rVt h ]?� �q�\©rV\«]�r g t e ~K¨ � ��p � ��� m [�w e u ���f 3^

���f VW ¹ ^V�§� Ä u��N] g ] _ c3�Z� ]z\"w"]?w mBl r m x rV["t m�mic ts] g rV\ _ ] _ rV\�Zc � m ]z»£] _ mBh {3]?t e }£]D["��]?wªr m ]?r _ lªl"h ] g r g _ l"h _ rVt�tsr e ] g r _z_ c3g w h \ jZmicZmil ] d r g�mih _ [�t|r g \"]z]?w"� c x ]?r _ lc x mil ]¯� d ] _ h ± _ rn}"� mig r _ mBhsc \"�Nr m5mil r m t|r e ] g?� � l r m r d"d�gic r _ l­h ��� mih tst"{nrVt h w mBc w�r e u§rV\"w h ��] � } c w h ]zwh \ mil ]¶r g _ l"hkm ] _ m [ g rnt1w hsg ] _ mBhsc \"� d [ g �i["]zw h \ mBl"h � g ] d£cVg�m�� � g ] _ ]?\ m r g�mih _ tk]�} eÃ�¯hkmBh \ � r h w e r ¹ Wf V� Äx®[ g9mBl ] gNd [ g �i["]z�&r�w"]z� hkj \ d"g�h \ _ hsd tk] c x � ["t mih tk]z{3]zt g ] _ c {3] g�e � _ l ] � ]?� h \­� l"h _ l mBl ] �­c � m _ c3�Z�­c \_ rn�i]?�Zr g ] w h � d�c �i]zw c x �Zc � m '[ h _ � t eV� ~ � r h w e r _ c \�� h w�] g � c \"t e�m � c tk]z{3]zts�zu�}�[ m�mBl ] _ c \ _ ] d�m�h �g ]?rVw h t e­j ]?\"] g rVt h�� ]?w mBcZ�­cVg ]�ts]�{3]zts�?u c3gImBc r _ c \ mBh \'[ c ["�&� d ] _ mBg [ ���¦�� [ � ] gic ["�Z]�¢�r �Zd tk]?� c x��i[ g { h {nrV} h t hÂm�e x r h ts[ g ]?� g ]zt|r m ]?w mBc4h \�rVw"]� '[�r m ] g ]zt h rV} h t hkm�e rV\"w x rV["t m

mBc ts] g rV\ _ ]­r g ] j3h {V]?\ h \ � ]z[ � rn\"\ � ��p&q9o�°Do�} cPc3� ¹ ^3�VX Ä u rVt c \ j � hkmBl ry�i[ �Z� r g�eªc x m ] _ l \ h P[�]?�x c3gIhk�­d"g�c { h \ j�g ]zt h rV} h t hkm�e rV\�wyx rn["t mImic ts] g rV\ _ ] �

� ��#$� � 8�>'Q �vE�Q �4<"J 3>aNc3�Zd ts] m ]y� e � m ] � rV\"w�\"] m � c3g�� c [ m r j ]?�­r g ]�rV\+]�¢ mBg ] � ]µx c3gi� c x d ] g x c3gi� rV\ _ ]�w"] j3g rnw�r mBhkc \1u� l ] mBl ] g _ rV["��]?w r _?_ h w"]z\ m rVtkt eyc3g�h \ m ]?\ mihsc \�rntst e u mBl"g�c [ j3l©g ]?t h rV} h t hkm�e d"gic }�ts] � � cVg �i] _ [ g�hkm�e«d"gic }P�ts] � � � ( c �5]z{V] g u h \b� c3� ] _ rV��]?�Ã]�{3]?\ g ]?t|r mBh {V]?t e � � rVtst d ] g x c3g�� rn\ _ ]�w"] j3g rVw�r mihsc \�� _ rn\ _ rV["��]["\�r _?_ ] d�m rn}"ts]�}�] l r�{ hscVg u d r g�mih _ [�t|r g t eyh \ mBhsjVl'm t e _ c \"� mig r h \"]?w g ]�rVt � mBhk� ]¶� e � m ] � � � � l ["�zu d ] g x c3g �� rV\ _ ] g ]� '[ hkg ] � ]?\ m � � [�� m }£] _ t c ��]?t e _ c [ d ts]zwy� hÂmBlÃmBl�c �i]¶x c3g �i] _ [ g�hkm�e rn\"w g ]?t h rV} h t hÂm�e3�� ] g x c3g�� rn\ _ ]Dw"] d ]?\�w"� c \«rT{nr h t|rV} h t hÂm�eZh \µ} cVmil«hÂm �¯�i] _ [ gihÂm�eµ� rV\ h x®]?� m r mihsc \��D~ ] �·j"� u d�g ]z{V]?\ mBhkc \

c x�w"]z\ h rVtk� c x���] g { h _ ] � rV\�w hkm � g ]?t h rV} h t hÂm�eÃ� rV\ h x®]z� m r mBhkc \"�;~ ] �·j"� u1x rV["t m#mBc ts] g rV\ _ ]�rV\"w�rVt m ] g \�r mih {3]_ cV�­d [ m r mihsc \ �­c w"]z� ��� � l�h � _ c \�³"["]?\ _ ] c x���["} g ]� '[ hsg ] � ]?\ m � h � h tstk["� mig r m ]?w h \ ¡ hkj [ g ]DW � �Frn� mBl ]g ] _ c \f{V] gij ]?\ _ ] c x)� l r m&h � cVmil ] g � h ��]Dw�] d"h _ m ]zw«rn��r d [ g ] mBg ]?]¶� mig [ _ m [ g ] �� l ] g ] _ c \'{V] g�j ]?\ m \ c w"]z� h \"w h _ r m ]?w } e rV\ rV� m ] gih � � ~ �n��h \ mil ]ª± j [ g ] _ c ["tkw c x _ c [ g �i]²}�]

� d t hkm¶h \ mBc �i] d r g r m ]Z}"[ m ]?�i��]?\ mBh rVtst eªh w"]?\ mBh _ rVt�\ c w"]z� h x mil ]��BrV\ _ mBhÂm�e²c x mil ] d [ g ] mig ]?]Z� mig [ _ m [ g ]�5] g ] hs�Zd�c3g�m rV\ m�� ( c �5]z{V] g u hkm&h �I\ cVm¯hs�Zd�c3g�m rV\ m � rV\"w h \Ãx r _ m�h tstk["� mig r m ]?�IrV\ hs�Zd�c3g�m rV\ mId£cVh \ m �r d"d r g ]z\ m t e w h »£] g ]?\ m �i[�} g ]� P[ hsg ] � ]z\ m � mBl r mÃc3gihkj3h \"r m ]yx gic3� �i]z] �Zh \ j t e w h � ��c3h \ m�g ]� '[ hkg ] � ]z\ m �r g ] h \�x r _ m }�]?� m�l rn\"w"ts]zw­} e r _ cV�­�Zc \ h \ m ] j3g r m ]?w � ] _ l rV\ h � � u g r mBl ] g mil rV\ mBg ]�r m ]?w _ c3�Zd ts] m ]zt e�i] d r g r m ]zt e3� ¡ cVg�hk�­d tk] � ]?\ mBh \ j rV�i��[ g ]zw rT{nr h t|rV} h t hÂm�e u hkm�h � mBg ["] mil r m w h »£] g ]z\ mFm ] _ l \ h '["]z� � r eh \�w"]?]zw�}�]Ã["�i]�x®["tIx c3g ~9� �;d"g ]�{3]?\ mih \ j�� rnt h _ hsc [��;w"]z\ h rVtk� c x��i] g { h _ ]Vu�~K^ �;d"g ]z{3]z\ mBh \ j r _z_ h w�]?\ m rVtw"]z\ h rVtk� c x¶�i] g { h _ ]nu�~KW ��d"g ]�{3]?\ mih \ j x r h ts[ g ]?��w"["] mBc x rV[�t m � mBl r m ]�¢ _ ]?]zw mil ] _ c {3] g r j ] c x#x rV["t mmBc ts] g rV\ _ ]Vu£~ � � ]z\"�i[ g�h \ j rVw"]� '[�r m ] d ] g x cVgi� rV\ _ ]&w"]z� d"hÂm ] h \ m ]z\ mBhsc \�rVt�r _ m �zu1~K� � ]?\"��[ gih \ j rnw"]� '[�r m ]d ] g x cVgi� rV\ _ ]�w"]?� d"hkm ]#["\ h \ m ]z\ mihsc \"rVt�r _ m �½rV\"w � e � m ] � � rVtkx®["\ _ mBhkc \"�zu§rn\"w²~K� � ]?\��i[ g�h \ j rnw"]� '[�r m ]

� �

Page 75: Practical Architectures for Survivable Systems and Networks (Phase

d ] g x cVgi� rV\ _ ]Dw"]z� d"hÂm ]�r _ m � c x ��c w �#º \ mil ] cVmil ] g¯l rV\"w�u�} e�m r �'h \ j r­� e � m ] � r mih _ { h ]z� c x mil ]?��]�i[ d"d£c �i]?w�t e w h »£] g ]z\ m rV� d ] _ m � c x5r�{nr h tsrV} h t hkm�e u hkm#h ��t hs� ]?t eµmil r m�� rV\ e _ c3�Z�­c \ � ] _ l rV\ h � � � _ rV\� c3gi� � e \"] g�j3h � mBh _ rVtst e3�

� rV\ eÃcnmBl ] gIh \ m ] g w"] d ]z\"w"]?\ _ h ]z�#rnts� c ]�¢ h � m?� ¡ cVg ]�¢�r �Zd ts]nu mBl ]¶rV� d ] _ m�c x h \ m ] j3g�hkm�e­g ]zt|r mih \ j;micd"g ]z{3]z\ mBhsc \ c x&["\"w"]z� hsg ]?w _ l rn\ j ]?�µ~ mBc w"r m r�u d�gic3j3g r � �?u ± gi� �Nr g ]nu l r g w��½r g ]Vu _ c3�­� ["\ h _ r mBhkc \"�� ]?w h r�u rV\"w � c�c \ �;h �;x®["\"w"r � ]z\ m rVt mic �i] _ [ gihÂm�e u g ]?t h rV} h t hÂm�e u d ] g x c3g�� rV\ _ ]Vu�rV\�w c x _ c [ g ��]y�i[ g �{ h {nrV} h t hÂm�e�h \ mil ]�tsr gij ] � oP]z{3] g rVt � rV\ h x®]z� m r mBhkc \"� c x mBl ]D\ c �¼["\ h \ m ]?\"w"]zw§� _ l rV\ j ] g ]� '[ hkg ] � ]z\ m r g ]h \�w h _ r m ]zw } e rª� l r gid ~ � � ~ mBl ]�] g � m � l"h tk] c _ mBcVmil"c3g�d ] h \ ]�r g t e²m ]?ts] d"l"c \ e��;h \ mil ]�± j [ g ]nu5rn\"ww h � _ [��i�i]zw�x®[ g9mBl ] gIh \µo§] _ mihsc \µ� � �¸^ � o hs�Zh t|r g t e u mBl ] _ c \�±�w�]?\ mBh rVt hÂm�e�c x)��]?\"� hkmBh {3] h \§x c3gi� r mBhkc \Z�i[ _ lrV� _ g9ePd�mBc3jVg r d"l�h _ � ] e � _ rn\�["\�w"] g��­h \"] � rn\ e w"]?� hsg ]zw�� e � m ] � d"gicVd ] g�mBh ]?� �¨�] d ]?\�w"]?\ _ h ]z� h \ g ]� P[ hsg ] � ]z\ m �Zr g ]Ã� c3� ] mBhk� ]z��\ cVm�g ] _ cVj \ h�� ]?w ["\ mBh tN�5]?tst h \ mBc w"]z� hsj \�rn\"w

hs�Zd tk] � ]?\ m r mihsc \ � ¡ c3g ]�¢"r �­d tk]Vu5]�¢ m ]z\"� h {3] g ]� '[ hsg ] � ]?\ m ��x c3g�g ]zt h rV} h t hkm�e rV\"w�r�{Vr h t|rn} h t hkm�e�� r eh \�w"[ _ ]�rnw"w hkmihsc \"rVt g�h � � ��� hkmBl²g ]?� d ] _ m�mBc �i] _ [ g�hkm�e rV\"w²�i[ g { h {nrV} h t hkm�e u���[ _ l rn� mBl"c �i] mBl r m�g ]z�i["t mx gicV� g ] d t h _ r mBhsc \ c x _ c3�Z�­c \ � ] _ l rV\ h � � � mBl r m½h \ migic w"[ _ ] � ["t mihsd tk] _ c3�Z�­c \�{P["ts\"] g rV} h t hÂmBh ]?�?u cVgmBl ]�["��] c x¾w h »�] g ]z\ m¯� ] _ l rn\ h � � � mBl r m¯h \ mBg�c w"[ _ ]¶w h »£] g ]?\ m {P["ts\"] g rV} h t hÂmBh ]?� � o hs�Zh t|r g t e u']�¢ m ]z\"� h {3]�i] _ [ g�hkm�e�� ] _ l rV\ h � � � � r e�l rT{V]Fw"]zts] m ] g�hsc ["��]z»£] _ m � c \ d ] g x c3g�� rV\ _ ]Frn\"wª� e � m ] � ["�Brn} h t hkm�e3� � cr�{ c3h w d ] g x c3g�� rV\ _ ]¶w"] jVg rVw�r mBhsc \1u���] _ [ gihkm�e _ c \ mBg�c ts�&r g ] c x m ]z\µw h �Brn}"ts]zw �

��) &% �P��� ( � � � �����)( �),N���b���5� ���"!��!�� $���9¼� %

�#�Ã\ cVm ]zw1u#]z\ m ] g�d"gih �i]²�i[ g { h {nrV} h t hkm�e h �Ãr g ]� P[ hsg ] � ]z\ myc \ mBl ]©]z\ m ] g�d"gih �i]�rV�yr4� l"c ts] � º#mBl ] g�i[ _ l�l�hsj3l ]z� m ��t|r e ] g r d"d t h _ r mihsc \ g ]� '[ hsg ] � ]?\ m � �ZhsjVl'm�h \ _ ts[�w"] d"g ]?��] g {nr mihsc \ c x l [ � rn\ª�Brnx®] m�e x cVgx gih ]?\"w�t e�l [ � rV\"�?u§w"]?� mBg [ _ mihsc \ c x1["\�x gih ]?\"w�t eZl [ � rn\"�N} e r m r _ mBh _ rVtR� e � m ] � h \�r l"c � mBh tk]�]z\f{ hkgic \P�� ]?\ m u£rV\"w�w"] m r h tk]?wªr _?_ c ["\ m rV} h t hÂm�eÃc x � e � m ] � rV\�w l [ � rV\ªr _ mBhkc \"� h \ m ] g�� � c x mil ]Fr d�d t h _ r mihsc \x®["\ _ mBhkc \�rVt hkm�e3�

o e � m ] � ��[ g { h {nrV} h t hÂm�e�m�e§d�h _ rntst e w"] d ]?\�w"� c \ m � c�m�e§d ]?� c x d"gicVd ] g�mBh ]?�zu�� c3� ] mihs� ]?� _ rVtstk]?w ��� � ���� �����Nd"gic3d ] g9mBh ]?��~ hk�­d t ePh \ j rT{nr h t|rV} h t hÂm�e�� rV\�w � � ���� � � � ��� � � � ��� ��d"g�c3d ] g�mih ]z�;~ hs�Zd t ePh \ j x®["\ _ mBhkc \�rVt_ cVgig ] _ m \"]?��� ��� ��t d ] g \�rn\"w o _ l \"] h w"] g ¹ � Ä�l r�{V]¯� l"c �&\ mil r m ]z{V] g9e�d"gic3d ] g9m�e _ rV\­}�]I]�¢ d"g ]?���i]?w rV� r_ cV� } h \"r mBhkc \ c x§x®["\ _ mihsc \"rVtV�irnx®] m�e¶d"g�c3d ] g�mih ]z� rn\"w¶t h {V]?\"]z�i� d"gicVd ] g�mBh ]?�zu g ]?tsr mBh {3] mBc w"]�±�\ hÂmBhsc \"� mBl r ml r�{3]�]z{ c tk{V]?wªx gicV� �)r �­d�c3g�m ¹ �T�f^ Äv� q�\ m [ hkmBh {3]zt e u�x®["\ _ mBhkc \�rVt��irnx®] m�eµd"g�c3d ] g�mih ]z� hk�­d t e mBl r m \ cVmBl �h \ j }�rnw l r d�d ]z\"�?u¾� l�h ts]�t h {3]z\"]?��� hk�­d t h ]z� mBl r m ]�{3]?\ m [�rVtst e � c3� ] mil"h \ j�j3cPc w l r d"d ]z\"� � q�\�w"]?]zw1u�Zc � m r d"d t h _ r mihsc \P��t|r e ] g�g ]� '[ hkg ] � ]z\ m �D~ ] �Áj"� u��i[ g { h {nrV} h t hÂm�e rV\"w l [ � rn\µ�irnx®] m�e�� rV\�wµ� e � m ] � �¼t|r e ] gg ]� '[ hsg ] � ]?\ m � l r�{3] _ cV�­d�c \"]z\ m � c x¾]?r _ l�m�ePd ] �¿ ]Fw c \ cVm \"]?]zw mBcÃ� r � ]�r d�g ] _ h ��]Fw h � mBh \ _ mihsc \ l ] g ];}£] m �N]z]?\ mBl ] m � c m�ePd ]z� c x d"gic3d ] g9mBh ]?� �( c �5]z{V] g u1�5]Fw c­g ] _ c3j \ h�� ] mBl r m � cV� ] c x mBl ];w"]z� hsg ]?w d"g�c3d ] g�mih ]z� l r�{3] mBhs� ]��¼w"] d ]?\�w"]?\ m rn� d ] _ m �� d r g9mBh _ ["tsr g t e­h \ l"hsj3l t e w h � migih }"[ m ]zwy� e � m ] � � �¡ r h tk[ g ] c x mil ]¶� e � m ] � c3g ��["}"� e � m ] � mBc ]z\�x c3g _ ];rn\ e c x�rF{nr gih ] m�eÃc x d"g�c3d ] g�mih ]z� _ rV\ g ]?��["t m¯h \

r t c �i� c xNr d"d t h _ r mihsc \µ�i[ g { h {nrV} h t hÂm�e3� o c3� ] c x mBl"c �i]F\"] _ ]z�i�Br g�e ["\"w�] g t ePh \ j d�gic3d ] g9mBh ]z� c \«� l�h _ lr d"d t h _ r mBhkc \��i[ g { h {nrV} h t hkm�e;� r e w"] d ]z\"wÃr g ] h tkts["� mBg r m ]zwZ\�]�¢ m�� q�\ ]?r _ l _ rn�i]Vu mBl ] m ] gi� ��� ��� ��� _ rV\]� '[�rntst e �N]ztst hk�­d t e rV\�]z\ mBhsg ] _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mBhsc \�� e � m ] � c3g r���["}"� e � m ] � mBl ] g ] c x �

o c3� ] c x mBl ]�\"] _ ]?���Br g9e d"g�c3d ] g�mih ]z�;r g ]�tsr gij ]zt eªmihs� ] h \"w"] d ]z\"w"]z\ m u�rVt mBl"c [ j3l � c3� ] c x mil ] �l r�{3] _ ] g�m r h \ mBhs� ]��¼w"] d ]?\�w"]?\ m r mimigih }�[ m ]z� �­¿ ] _ c \"� h w"] g�mBl ] j ]?\�] g rnt d�gic3d ] g9mBh ]z�D± g � m rV\"w mBl ]?\g ] _ c \�� h w�] g�mBl"c �i]I� hkmil � d ] _ h ± _ g ]?rVtÂ� mBhs� ]½r mimBg�h }"[ m ]?� � ¡ c3g � hs�Zd t h _ hkm�e u��5] h \ _ ts["w�]I\"] m � c3gi�'h \ j rn\"w

� �

Page 76: Practical Architectures for Survivable Systems and Networks (Phase

_ cV�­� [�\ h _ r mBhkc \"� h ���i["]z�FrV��rV\ h \ m ] j3g rnt d r g�m�c x mBl ]­� e � m ] � h ���i["]z�?u d r g�mBh _ ["tsr g t e«h \ w h � migih }"[ m ]zw� e � m ] � � �

�>�3>P=�=?<�Q !+= !�=�ST>�� =z> ���Q�H®S ! O)Q¸E�O�>'QTS¸H®>P= �� � !�=zS�> � H J£ST>�RQ�H®S ! � � g ]�{3]?\ mih \ jµ� rnt h _ hsc [��F~ rV\"w1u mic � c3� ]�]�¢ m ]z\ m u r _?_ h w"]z\ m rVt � ]z»£] _ m � c \mil ] l r g w��½r g ]Vu�� e � m ] � � c x m �Nr g ]nuRrV\"w h \ m ] g _ c3�­� ["\ h _ r mBhkc \"� �

� � !�=zS�> � <��"<�H L < �¾H LKH S ! � � g ]�{3]?\ mih \ j � e � m ] � rV\"w _ c3�Z� ["\ h _ r mihsc \ c [ m r j ]z�?u1rn\"wª]z{V]?\ m ] � �d�c3g r g�e ["\�r�{nr h t|rV} h t hÂm�eªc x g ]?� c [ g _ ]?� � o§[ _ l c [ m r j ]?� � r e�h \ _ ts["w"] � rnt h _ hsc [�� c3g r _z_ h w�]?\ m rVtw�]?\ h rVts� c x¾� e � m ] � ��] g { h _ ] �

� � !�=zS�> � 3E�J � %�>PJ£S¸H®<�LKH S ! � � g ]z{3]z\ mBh \ j mil ]ª["\"w�]?� hkg ]zw w h �i��] �Zh \�r mBhsc \ c3g r _ '[ h � hkmihsc \ c x��]?\"� hkmih {3]µ� e � m ] � _ c w"]�rV\"w�w�r m r§u d r g9mBh _ ["tsr g t e h x mBl ]�r d"d t h _ r mBhkc \ _ rn\+}�] _ c3�­d�gic3�Zh ��]?w �º#mil ] g � h �i]nuPx cVg ]�¢�r �­d ts]Vu � \ c �&tk]?w j ] c x mil ]¯� e � m ] � w"]?� hsj \�u�r¶� d ] _ h ± _ rVt jVc3gihÂmBl"� u3r d"h ] _ ] c x_ c w�]Vu'r d rV����� c3g w1uPr _ g9ePd�mBc3jVg r d"l�h _ � ] e uPr�\"] m � c3g�� rV[ mil ]?\ mBh _ r mic3g u cVg r d"h ] _ ] c x£]� '[ hkd"� ]z\ m_ c ["tkwµtk]�rVw mic r�� e � m ] � ��["}f{3] g � hkc \ �

� ��S¸:�ERQnH �f<�S¸H®E�J <�J'% < �3E�� J£S�<��¾H L H®S !²E �½= !�=zST>�� =¶<�J % �)=?>'Qn= � �#�i��[ gih \ j�mil r m r�� e � m ] �h � _ r d rV}�ts] c x _ c \ migic tkt h \ j � l"h _ l �i[�}"� e � m ] � �DrV\"w«� l"h _ l ["�i] g ��r g ];[�� h \ j hkm?��º#mBl ] g � h �i]nu hkm� r e }�]D{P["tk\"] g rV}"ts] mBc � d�cPc ±�\ j r mim r _ � �?u d ]z\"] mig r mihsc \"�zu�rV\"w cnmBl ] g x c3g�� � c x �­h �i["��] � �¯x m ] grn\ e �i[ _ l r m�m r _ � u mil ]�� e � m ] � � � h \�rV} h t hkm�e;mBc�d"g�c { h w"] g ]?rVtÂ� mBhs� ];~ c3g r m ts]?rV� mIg r d"h w � r _z_ c ["\ m �rn} h t hkm�e rV\"w�rV["w hÂm � mBg r h t£rV\�rVt e � h � � r e ts]?rVw mBc rVw"w hkmBhkc \�rVt _ c3�Zd"g�c3�­h �i]z� c x ��[ g { h {Vrn} h t hkm�e3�

� �Ã<�S�<yHKJ£S�>��RQ�H S ! � � g ]z{3]z\ mBh \ j ["\�w"]?� hsg ]zw�rnt m ] g r mihsc \ c x h \ d [ m w�r m r§u h \ m ] g \�rnt"� mic3g ]zw­w�r m r�u cVgc [ mBd [ m w"r m r � ¨�r m r h \ m ] j3gihÂm�eÃh \ _ ts[�w"]?� h \ m ] g \"rVt�w�r m r _ c \"� h � m ]z\ _ e ~ d r g�mih _ ["t|r g t e�hs�Zd£c3g9m rV\ mh \yr l�hsj3l t e w h � d ] g �i]zw«]?\f{ hsg�c \ � ]?\ m�� rn�&�5]?tkt�rV�&]�¢ m ] g \�rnt _ c \"� h � m ]?\ _ e � hkmilymil ] g ]?rVt�� c3g tkw �

� �Ã<�S�<�<��"<"HKL®<�� HKL H®S ! � � g ]z{V]?\ mBh \ j w h � g [ d�mihsc \"� h \ mBhs� ]?t e r _?_ ]z�i� mBc w�r m r�u h \ _ ts["w h \ j ��]?\"� c3gw"r m r h \�r _ c \ mBg�c t�� e � m ] �µ� � ["t mihsd tk]�{3] g � hkc \"� c x _ gihkmih _ rVt�w�r m rZrV\"wªrnt m ] g \�r mBh {V]��i]z\"� c3g � _ rV\l ]?t dyh \ _ g ]�rV��]Dw"r m r�r�{nr h tsrV} h t hkm�eV�

� �Ã<�S�< 3E�J � %�>PJ£S¸H®<�L H®S ! � � g ]z{V]?\ mBh \ j [�\"w"]?� hsg ]?wµw�r m rFw h � _ t c ��[ g ] � ¡ cVg ]�¢�r �Zd ts]nu"r d ]?\"] mBg r¸�mic3g _ c ["tsw c } m r h \��i]z\"� hÂmBh {3]&w�r m r mil r m � c ["tsw _ c3�Zd"g�c3�­h �i] mil ]�r d"d t h _ r mBhsc \ � � rV} h t hkm�eDmBc x®["tk±"tsthÂm � g ]� '[ hsg ] � ]?\ m � h \�r l"c � mBh ts]�]z\'{ hkgic \ � ]?\ m?�

�>�3>P=�=?<�Q !+J�>'S�C;E�Q � =?>����QnH S ! O Q¸ERO�>'QTS¸H >P= �� µ>fS�C;ERQ � H J£ST>�RQ�H®S ! � � g ]z{V]?\ mBh \ j r mim r _ � � c \y\"] m � cVgi� \ c w"]?��rV\"w c \ mil ] _ c3�Z� ["\ h _ r mihsc \� ]?w h r mBl r m rVt m ] g \"] m � cVgi� � m r m ]z� �

� µ>fS�C;ERQ � <��"<"HKL®<�� HKL H®S ! � ¨�] m ] _ mBh \ j u d"g ]�{3]z\ mih \ j u½rV\"w g ] _ c {V] gih \ j x gic3� w"]?\ h rVtÂ� c x|����] g { h _ ]r mim r _ � �zu5��[ _ l rn� c [ m r j ]?� c x�\"] m � c3g�� \ c w�]?�ZrV\"w r _z_ ]?���­w�]z{ h _ ]?�?u5]?tk] _ migic3� r j \�] mBh _ h \ m ] g �x®] g ]z\ _ ] c \ mil ] _ c3�Z� ["\ h _ r mihsc \"� � ]?w h r � �#t m ] g \�r m ] g�c [ m ]z�?u g ]?w"[�\"w�rV\ m \ c w"]z�?u¾rV\"w cnmBl ] gm ] _ l \ h '["]?�&x c3g x rV[�t m½mic ts] g rV\ _ ] _ rV\ _ c \ migih }�[ m ] mic ��] _ [ gihkm�e rV�I�N]ztst �

� µ>fS�C;ERQ � %�<�ST< 3E�J � %�>PJ£S¸H®<�L H®S ! � � g ]�{3]?\ mih \ j�mil ]N["\�w"]?� hsg ]zw h \ m ] g _ ] d�mihsc \ c xR["\"]?\ _ g�ePd�m ]?wcVg w"] _ g�ePd�m rV}"ts] h \�x c3g�� r mihsc \�u m�ePd"h _ rVtst e�mil"gic [ j3lbmBl ]©["�i] c xD]z\ _ g9e§d§mBhsc \1u�� m ] j rV\ c3jVg r d"lfe ucVd ] g r mihsc \"�¶��] _ [ gihkm�e u rV\"w cnmBl ] g�m ] _ l \ h P[�]?�Fx c3g w"]zx®]?r mBh \ j r _ '[ h � hkmihsc \ c xIw�r m rªrV\�w mBg r _rn\�rVt e � h � mil r m _ c [�tswy}£]¶["��]?w mBc rn»£] _ m \"] m � cVgi� rV\"wy� e � m ] � ��[ g { h {Vrn} h t hkm�e3�

� �

Page 77: Practical Architectures for Survivable Systems and Networks (Phase

� ��S¸:�ERQnH �f<�S¸H®E�J+<�J'% <��3E �)J£ST< �¾H LKH S ! E��#J)>fS�CFERQ � <��3>§=?=­<�J'% 3E�J£STQ¸E�L � �#tkt�\"] m � c3g��\ c w"]z�&rV\"wyr _z_ ]z�i� d£c3h \ m � � [�� m }�]¶rVw"]� P["r m ]zt e _ c \ mBg�c tstk]?w1u mBc�g ]zw"[ _ ] mil ] c3d"d�c3g9m ["\ hÂmBh ]?�5x cVg� d£cPc ±�\ j r m�m r _ � �?u � r h \ m ]z\�rV\ _ ]�r m�m r _ � �zu�rV\"w cnmBl ] g x c3g�� � c x �­h �i["��] � ¨ hsjVhkm rnt � hkj \�r m [ g ]z�rn\"w cVmBl ] g _ g�ePd�mic3j3g r d"l"h _ m ] _ l \ h '["]z��x c3g rV[ mBl ]z\ mih _ r mBhkc \ _ rV\y}�] l ]?t d x®["t �

� µ>fS�C;ERQ � %�<�ST<�H J£ST>�RQnH S ! � � g ]�{3]?\ mih \ j ["\"w"]z� hkg ]?w�rVt m ] g r mihsc \ c x _ c3�Z� ["\ h _ r mihsc \"� mBl ] � ���]?tÂ{3]?� � x cVg ]�¢�r �Zd ts]nu mil"gic [ j3l r _ c3� } h \�r mihsc \ c x ] gig�c3g � _ c3g�g ] _ mBh \ j _ c w"]z�¯rV\"wÃ]?\ _ g�ePd�mihsc \ �� l�h � �­hkj3lfm }£] _ c \"� h w"] g ]?wFr&� e � m ] � g ]� '[ hsg ] � ]?\ m h x§]?\"w§� mBc �¼]?\"w h \ m ] j3gihÂm�e�h �)w�]?� hkg ]zw1uV}"[ m _ rV\rnts� c }�]Dr�\"] m � c3gi�Ãg ]� '[ hkg ] � ]?\ m � l ]z\«t h \ � ��} e ��t h \ � ~ \ c w"]�� mic ��\ c w"] �Nd"gicVm ] _ mBhsc \ h �I\"]?]zw"]?w �

�#t mBl"c [ j3l¶mBl ]�x c3g ] j3c3h \ j � e � m ] � rV\"w;\"] m � c3gi� �i] _ [ g�hkm�e�h ���i["]z� rVtkt hk�­d t e r m�m ] �­d�m � mic _ c \"� mig r h \["�ir j ]�} e ["�i] g �?u c3d ] g r mic3g �zu§� e � m ] � d"g�c3j3g r �­� ] g �?uPrV\"wyrnw �­h \ h � mBg r mBc3g �?u mil ] e­h \"]�{ hkm rn}"t e w"] d ]z\"wmBc � c3� ]D]�¢ m ]z\ m�c \ _ c3�­d t h rn\ m � e � m ] � ["��];} eµmBl"c ��] d ] c3d ts] � � h �i[��i];} e r d"d r g ]?\ m t e rV[ mil"c3g�h�� ]zwh \�w h { h w�[�rVts� h �¯r��i] gihsc ["� d£cVm ]?\ mBh rVt d"g�c }"tk] � h \ � rV\ e r d"d t h _ r mBhsc \"� �

�>�3>P=�=?<�Q !+= !�=�ST>�� <"J % J�>fS�C;ERQ � Q¸>PLKH®<�� HKL H S !4O Q¸ERO�>'QTS¸H >P= �� G�< �)L SµS�E£L®>'Q¸<�J 3> � � g ]z{V]?\ mBh \ j [�\"w"]?� hsg rV}"ts];]z»£] _ m � g ]?��["t mih \ j x g�c3� x r h ts[ g ]?� c x�["\"w"] g t ePh \ jl r g w��Nr g ] _ c3�Zd£c \"]?\ m �zu��i["}�� e � m ] � �?u c3g�h \�w"]?]zw mil ]�]?\ mihsg ];� e � m ] �µ�F� �i��]?\ mBh rVtst e u�x rV[�t m�mic tÂ�] g rV\ _ ] h ��} cVmBl r � e � m ] � h \ m ] j3g�hkm�e h ���i["]ªrV\"w r4� e � m ] � g ]zt h rV} h t hkm�e4h �i��["] ��aNc \"� mig [ _ mBh {V][��i] c x g ]?w�["\"w�rV\ _ eªh ��]z�i��]?\ mBh rVt � o§[ g { h {Vrn} h t hkm�eÃh ��r d r g�mBh _ ["tsr g _ c \ _ ] g \ª� l ]?\ mil ]F\ cV�­h \�rVtx rn["t m � mBc ts] g rV\ _ ] _ c {V] g r j ] h �I]�¢ _ ]z]?w"]zw �

� G �)J VSTH E�J�<�L 3E�Q¸Q¸>�VS¸J�>§=?= � ���i�i[ gih \ j mBl r m r­³Rr�� h \ mBl ]�r d"d t h _ r mihsc \ c3g�h \ mil ] _ c3�­d [ m ] gcVd ] g r mih \ j � e � m ] � u cVg r l [ � rV\�] gig�c3g�h \ � e � m ] � � r h \ m ]z\�rV\ _ ]Vu _ rV\"\ cVm _ c3�Zd"gicV�­h �i] mBl ]r d"d t h _ r mihsc \ �D�¶cPc w«� c x m �Nr g ]�]z\ j3h \"]?] gih \ j u1w"]�{3]?t c3d"� ]?\ mDd"g r _ mBh _ ]z�?u�rV\"w²� e � m ] � c3d ] g r mBhsc \r g ] hs�Zd�c3g�m rV\ m u�}�[ m _ ts]?r g t e r g ]¶\ cVm ]z\ c [ j3l } eÃmBl ] � ��]?tÂ{3]?� �

q m&h �I[��i]zx®[�t mBc \ cVm ] mBl r mImil ]¶�i] _ [ g�hkm�e rV\�w g ]?t h rV} h t hÂm�e�d"gic3d ] g9mBh ]?� l r�{3]D� cV� ] mihs� ]���w�] d ]?\"w"]z\ mr m�mBgih }"[ m ]?�?u��i[ _ l rV� mBl ]�x c tkt c � h \ j��

�>�3>P=�=?<�Q ! S¸H��4>3@ %�>'O�>PJ %�>PJ£S­=?>���)Q�H S ! O)Q¸E�O�>'QTS¸H®>P= �� M�>P<"L @�S¸H��4> <���<�HKL®<�� HKL H S ! ~ h \ _ ts[�w h \ jÃmil ]�� e � m ] � u¾w�r m r�u rV\"w cVmBl ] g¶g ]?� c [ g _ ]?� ���y� \"��[ gih \ jmil r m¶g ]�rVt � mBhk� ] d"gic _ ]z�i� h \ j _ rV\ }£]�w c \"] h \�r mihs� ]?t e �Nr e u d"gicVm ] _ mBh \ j r j r h \�� m¶� rVt h _ hsc ["�it ecVg r _?_ h w"]z\ m rVtst e _ rV["��]?w«w�]?t|r e � �

� M�>P<"L @�S¸H��4>;< �3E��)J£ST<�� H LKH S ! �i[ _ l rV� rV\ c3� rVt e w�] m ] _ mihsc \�rV\�w �­h �i["��]½w"] m ] _ mBhsc \µ~ ] �·j"� u ¹ �T�3��uWVXV� Ä

�>�3>P=�=?<�Q ! S¸H��4>3@ %�>'O�>PJ %�>PJ£SZQ�>PL H < �¾H LKH S ! O)Q¸E�O�>'QTS¸H®>P= �� A�H � >§L�! %�>'S�> VSTH E�J+<�J'% 3E�Q¸Q¸>�VS¸H®E£J�E�� %�>��H <�J�SÃ= !�=�ST>�� ��>P:�<��H ERQ

�h \ _ ts["w h \ j�g ] _ c \P�

± j [ g r mBhsc \ h \ mBl ]�x r _ ] c x¶\ c \ mBc tk] g r m ]zw+x rV["t m � c3g�d ]?\"] mBg r mBhkc \"� � p¯] _ c {3] g�e x g�c3� �i] g�hsc [��c [ m r j ]?� � r eªc3g�� r e \ cVm }£]ZrVtkt c �5]?w mBcyh \ _ [ g t c \ j mBhk� ]Fw�]?t|r e � c3g�l [ � rn\ h \ m ] g {3]z\ mihsc \ �¿�l ]?\"]�{3] g�l [ � rV\ h \ m ] g {3]z\ mBhsc \ h � \ cVm d�c ��� h }�ts]Vu mBl"c3g�c [ j3l rVw§{Vrn\ _ ]zw d tsrV\"\ h \ j�h ��\"] _ ]?�i�ir g�eV�

� M�>P<"L @�S¸H��4>Ã< �3E�� J�ST<�� HKL H®S ! ��[ _ l rn�&rV\ c3� rVt e w"] m ] _ mBhkc \�rV\"w �­h �i["��]�w"] m ] _ mBhsc \µ]�¢ m ]?\�w"]?wmic �i[ g { h {nrV} h t hkm�e u g ]?t h rV} h t hkm�e uPrV\"wyx rV["t mNmBc tk] g rn\ _ ] �

� �

Page 78: Practical Architectures for Survivable Systems and Networks (Phase

�>�3>P=�=?<�Q !�O�>'Q �¼ERQ � <�J 3>«O Q¸ERO�>'Q¸STH >P= �� G �)J VSTH E�J�<�L S¸H��4>PLKH J�>§=?=

���[ _ l rV��� migih _ m } c ["\�w"� h \ l r g w§� g ]?rVtÂ� mBhs� ]½� e � m ] � �zu c3g }£]z� m ��]z» c3g9m

h \ m ]?\ mihsc \"� h \Ãx®[ ����e � g ]?rVtÂ� mBhs� ]#� e � m ] � � � �>�3>P=�=?<�Q !�ERO�>'Q�<§S¸H E�J�<�LNO)Q¸E�O�>'QTS¸H®>P= �

� � ���i]?\ mih rVtkt e ]�{3] g9e �i] _ [ gihÂm�e u g ]?t h rV} h t hÂm�e u d ] g x c3gi� rV\ _ ]Vu c3gDcVmBl ] g x®[�\ _ mihsc \�rnt d"gic3d ] g9m�e²l rV��r� rV\ h x®]?� m r mihsc \ h \ cVd ] g r mihsc \�rnt d"g r _ mih _ ] � � e§d�h _ rntst e u h \�r d�d"gic3d�gih r m ] c3d ] g r mihsc \"rVt � rV\"r j ]��� ]?\ m _ rn\�{ hkmih r m ]�rn\ e c x mBl ]«w"]z� hsg ]?w x®["\ _ mihsc \"rVt d"gicVd ] g�mBh ]?� � � l ["�?u g ]� '[ hsg ] � ]?\ m � � ["� mrnw"w g ]z�i� c3d ] g r mBhkc \�rVt _ l r g r _ m ] g�h � mih _ � � q¼x#^n��� l"c [ g _ c {V] g r j ] h �F\"] _ ]z�i�Br g�e u mBl r m�l rV��� mBgic \ jhk�­d t h _ r mBhkc \"� c \ cVd ] g r mihsc \�rnt d�g r _ mBh _ ]?�zu�rV\"w � r e �5]?tkt1�i[ j3j ]?� m½mBl r mIc [ m � c [ g _ h \ j�c x�� e � m ] �rn\"w­\�] m � c3gi� rVw �Zh \ h � mig r mihsc \ � r e \ cVm }£]�r¶� h �i]&� mig r m ] jVe � ]�{3]?\ h x�rVt �Zc � m � h \"� m rV\ m rV\�] c ["�] � ] gij ]z\ _ e _ c {3] g r j ] h ��r�{nr h tsrV}"ts] � ~ � l ] g�h � �Dc x�["\ � \ c �&\ mBl"hkg w§�v� cVg tsw;�i["} _ c \ mig r _ mBc3g �5r gic ��]h \ÃrFw h »�] g ]?\ m _ c \ m ]�¢ m uRrnx m ] gNmBl ] � ]�r g �9^VX3XVX d"gic }"ts] � _ c w"] g ] � ]?w h r mihsc \�x cVg5mBl ]�� hsg � g r _aNc \ migic t�� e � m ] � �?uf� l ] g ]¯rVt �Zc � m rVtst mBl ] g ] � ]?w h r mBhkc \��NrV� w c \�]I} e�aNl"h \�]?�i]&\�r mBhsc \�rVts� ["\"w"] g��["} _ c \ mBg r _ m u g ] d£c3g9m ]zw"t e [�\P}�] � \ c �&\"� m#mic�mil ] ¡ ]?w"] g rVt��¯{ h r mBhkc \Ã�#[ mBl"c3g�hkm�eV�À�

º \"] c x mBl ] � r ��c3g _ l rVtkts]?\ j ]?� c x§� e � m ] � w"]�{3]?t c3d"� ]?\ m rV\"w c3d ] g r mihsc \ h � mBc ["\"w"] g � m rV\"w � ��� � � � �rVtkt mil ] g ]zts]z{nrV\ m&g ]� '[ hsg ] � ]?\ m �zu�rV�½�5]?tkt�rV� mil ] hkg½hs�Zd t h _ r mihsc \�� c \µt c �N] g � e � m ] � tsr e ] g �D~ h \ _ ts[�w h \ jl r g w��Nr g ]DrV\"w _ cV�­� [�\ h _ r mBhkc \"� � u"rV\�w mic­cVgij rV\ h�� ] mBl ]¶� e � m ] � w"]�{3]zt c3d"� ]?\ m r _z_ c3g w h \ j t e3�¡ [ g�mil ] g¯h ���i["]z� c \y� l"h _ l �i[ g { h {nrV} h t hkm�e w"] d ]?\�w"� h \ _ ts[�w"] l [ � rV\�}£] l r�{ hsc3g � c \ mil ] d r g�m¯c x

� e � m ] � w"]?� hsj \"] g �¶rV\�w hs�Zd ts] � ]z\ mic3g �zu cVd ] g r mic3g �zu1["�i] g �zu rn\"w � r h \ m r h \"] g �?uRx c3g ]�¢"r �­d tk] � rn\"wr _ m � c x ��c w � ( c �5]z{V] g u mil ]?��] � r e }�]�rV\ mBh _ hsd r m ]zw mBc r _ c \"� h w"] g rV}�ts]#]�¢ m ]?\ m } e �i[ hÂm rV}"tk]#� e � m ] �w"]z� hsj \«rV\�w cVd ] g r mihsc \Ã� hkmilyg ]?� d ] _ m¯mBc �i] _ [ g�hkm�e u g ]?t h rV} h t hÂm�e uPrV\"w d ] g x cVgi� rV\ _ ] _ c \"� h w"] g r mihsc \"� �q�\­rV\ e�d r g�mih _ ["t|r g r d"d t h _ r mihsc \�u _ ] g�m r h \�{§[�ts\"] g rV} h t hÂmBh ]z� � r e \ cVm ]�¢ h � m u c3g � cV� ] c x mil ] mBl"g ]�r m �

mBl r m _ c ["tsw�]�¢ d�c �i] mil"c ��];{P["ts\"] g rV} h t hÂmBh ]?� � r e \ cVm ]�¢ h � m u c3g&mBl ] gih � � � � r e }�]Fw"]z] � ]?w h \ _ c \"�i]�� '["]?\ mih rVt � q�\ª��[ _ l _ rV��]?�zu mBl ]��i[ g { h {nrV} h t hkm�e d"gic }�ts] � � r e }£]F� hs�Zd t h ±�]?wy� c3� ]�� l r m?� q�\ j ]z\"] g rVtvul"c �5]z{3] g u hÂm¶h ��{3] g�e w�rV\ j ] gic [�� mic }�rn�i]�� hs�Zd t h ± _ r mBhsc \"� h \ � e � m ] � w"]z� hkj \1u hs�Zd ts] � ]z\ m r mBhkc \1u cVgc3d ] g r mBhkc \ c \ªrV���i[ �Zd�mBhkc \"� mBl r m#� r e \ cVm }£]¶{nrVt h w h \ d"g r _ mBh _ ] � � l ] g ]�x c3g ]nu j3g ]�r m _ r g ] � ["� m }�]m r � ]?\ micFd"gic { h w�]�rVw"]� P["r m ]¶rV���i[ g rV\ _ ] h \ÃrV\ e ]z» c3g�m � mBl r m r g ] d ] gi�Zhkm�m ]?w mBc�hkj \ c3g ] c \�] c3g½�Zc3g ]c x mBl ]�x c3g ] j3cVh \ j \"] _ ]z�i�Br g�eµd"gicVd ] g�mBh ]?� �

��)�� � &% �'�"�)( � ��2 ��� ���"!��!�� $�9��¼� %

o§[ g { h {nrV} h t hkm�e�h � � ]�rV\ h \ j x®[�t d"gihk� r gih t e rV�)rV\�] � ] gij ]z\ m¾d"g�c3d ] g�m�e¶c x"rV\D]?\ mihsg ] _ cV�­d [ m ] g rV\�w _ c3� �� ["\ h _ r mBhsc \�� e � m ] � _ c3�­d ts]�¢£u c3g u �­c3g ]5} gic rVw�t e u c xRr _ c tkts] _ mBhkc \ c x _ c3�Zd [ m ] g ��}�rV��]?w�r d"d t h _ r mihsc \�� �o§[ g { h {nrV} h t hkm�e rVts� c�mBg rV\"� _ ]?\"w���t c �N] g �¼t|r e ] g�d£c t h _ h ]z� g ]?tsr mBh \ j­mic �i["}�� e � m ] � g ]?t h rV} h t hkm�e u h \ m ] j3gihÂm�e urV\"w mBl ] t hs� ] �«a ] g�m r h \4rV� d ] _ m � c x½�i[ g { h {nrV} h t hkm�e r g ] � ]�rn\ h \ j x®["t�� hkmBl4g ]?� d ] _ mFmicªl r g w��Nr g ]Ãrn��5]?tst �

o c3� ] c x mil ] d"g�c3d ] g�mih ]z� c \F� l"h _ l r d"d t h _ r mihsc \D�i[ g { h {nrV} h t hÂm�e�m�e§d�h _ rntst e w"] d ]z\"w"��r g ] h tkts["� mBg r m ]?wh \ � rV}"tk]IW � �3uf["\"w�] g mBl ]&r d"d"g�c ¢ hk� r m ] l ]?rVw h \ j � c x��i] _ [ g�hkm�e u g ]?t h rV} h t hkm�e u�rV\"w d ] g x c3g�� rn\ _ ] � � l ]z�i]mBl�g ]?] l ]�rVw h \ j � d r g�mBh rVtst e�c {3] g t|r d u�]z{V]?\«r �­c \ j;mBl ]�w h »£] g ]?\ mI� rV\ h x®]z� m r mBhkc \"�½r m ]�r _ l x®["\ _ mBhkc \�rVtt|r e ] g?� ¡ c3g ]�¢�r �Zd ts]nu1� e � m ] � h \ m ] jVgihkm�e r m rV\ eªd r g�mBh _ ["tsr g t|r e ] g _ ts]?r g t e _ c \ mBg�h }"[ m ]?� mBc �i] _ [ g�hkm�e ug ]zt h rV} h t hkm�e u�rV\"w d ] g x c3gi� rV\ _ ] r m�l"hsjVl ] g tsr e ] g � � o hs�Zh tsr g t e u d"g ]�{3]?\ mihsc \ c x � rVt h _ hsc ["�£rV\"w�r _z_ h w�]?\ m rVt

� �

Page 79: Practical Architectures for Survivable Systems and Networks (Phase

�zA/=�;�9�03&$=/!�J � #L;�A�%?039�" �g#LJ306!87 03J3039�" �j#%�( &,%?+1!�=�;#J3!",#K% ;&,=/;�#K-/9�2 ;�&$=�;#K-�942 ;&,=/;�#K-/9�2iW���:���:] �W���F� R ��R �S�:Q�� � �e`�] �N���F� R �S�:� � �<� � � � �e`�] �W���F� R ���4���$� R � ��� � R ���S�:]���$�:��������S��] �4O8��V:�<� � � R ]L�S�S� ��R���R Q,] ��O8�,V:��� � � R ]L����� ��R ��R Q�] �4�����\��Y�������]��O8� ��R �:] �� �����:� � O8� R � � �e` _L���F� R ��R ������Y3�Vf�4� �4O8��V:�<� � � R ]L�S�S� ��R���R QUN����� � V:��� � � R UW����� � V���� � � R ��� R VX� � � R �<�zV:���S���4VX� R ���S�:] uL��� � � Vf� � � � � ����� � � � �e`�]����Y��exh����� ��R ���:Q� � �e`g� R O ���4O8� R O�� R V:`�] �S����� a>� � �c�\�$�:��YG���S�F� R V:��]q uL| w V:� R �,O�� R � � �<� � �e` ���������� R �4����]8�S��Vf� � �:�S` YG� R VX� � � R �<�^� � �c�:� ��R ���S�k � O�O8����xh����� uL| ��R �S�:Q� � �e`g� R O ��� R VX� � � R �<�zV:���S���4VX� R ���S�:] ��� R VX� � � R �<��� � ����� ��R �4���q k~| � r\stkvu�] V:� R �,O�� R � � �<� � �e` ���4O8� R O�� R V:`�]�r\s ���V b ����] ��Y/| �:��]������������ r\sh��]r��h�W],� T � stU ��R r��h�W]�|}���Lxh�����] ���������� R �4����]8�S��Vf� � �:�S` � R O �,��� ���:� � ���S�|}���Kxt�<�S�4w r\s �V:Vf�4���tV:� R ���S�����MN�f�exh��� b ��R Q MW�f�ext�<�S� ��R ���:Q� � �e`�] MN�:�exh����� ��R �S�:Q�� � �e`�] MW�f�ext�<�S�W�S_������Q�_����8�W� R Oq MN�:�exh�����?w V:� R �,O�� R � � �<� � �e`] �:�S����PVf���S�S��VX� � � R � R O Q���<��� R ������O������ � � Vf��]

� � � � ���<� � � � �e`�] Y3�<�����P��������S� R Vf� ��� �S�:� R ��� � � �j�S���8� ��R Qc� R OR �8O8� R � R �S�����$�:���<� � � � �e`] ��R �S�S� R ��� � ��� � � R � R O ����_���� ��R YG���������S��Vf�������<��$�:���N�<�8�S_�� R � � V:�<� � � R ] ����8� ��R Q,]8�����,�4V � �<����` Y3�VX����S��]8�����$��V � �<����`�4���$��V � ������` x � �������4��� ��R x � �������4���h�S� � ��R Q ��� R O8x � OL��_

T �,���S�<� ��R Q T u ��R �S�:Q�� � �e`�] T u ��R ����Q�� � �e`] T u ��R �S�:Q�� � �e`�]��`8�����:� O��<�S�cVf� R �,O8� R � � �<� � �e`] Y3�<�����P��������S� R Vf�] Q���<��� R ������O������ � � Vf��]q T u�w Q���<��� R ������O������ � � Vf��] ���� R Oy����` R V�_��S� R `�] � � � � O�� R V:�j��Y/O8�4��O8���8V b �:]

T u R � R ���<�c�,���S��� � � � �e`�] �<��V�_ ������R Q8�?���V b ��� �$�:��YG���S�F� R V:�\��8� � � ��� ��� � � R ]T u�O8� � �:�������c� R �N� R O T ugO�� � ��������c� R �N� R O T u�O8� � �:�������c� R �N� R O�F� ��R ��� R � R V:��] T u �F� ��R �S� R � R Vf� �F� ��R ��� R � R V:������:�N���8��_�� R � � V:�<� � � R

�W�<��O8xt�<�S� UjV:Vf�4���PV:� R ���S������] �N| Y3�<�����P��������S� R Vf�] p ���8Vf�4�������f�?�c�������`����$�:�4O^]q �N| w ���S�<�S��Vf� � � R O8���F� ��R ��] ��R �e�S����Vf� � � R ���:���S`�] V:���c��� R�� V���� � � R ��� R O8x � OL��_���]

�W| R � R �S�<�c�$�:���<� � � � �e`] �:�S�����aoVf����S��Vf� ��R Q�V:�LO�����] V:� R ��� R � � � R V:� R ���S���>]V:� R ��Q������� � � R Vf� R �S����6] �N| Vf����S��Vf� R �4����] �O8��dK���<��� �N| Vf� R ��Q����S�<� � � R ]���S�<�S��Vf� � � R �<Q� ��R �e� ���S�<���4VX� � � R ��Q� ��R ��� ���S�<�S��Vf� � � R �<Q� ��R �e���R ��� R � � � R �<� ��R ���:��YG�:�S� R Vf��] ��V�V � O8� R �S��� ��R �S�:��YG�:�S� R V:��] � R ` ��R ������YG����� R Vf�]�W| O8� � ��������c� R � �N| O8� � �:�������c� R � �W| O8� � ��������c� R �

�/�<����� `�ÁÅ� u8���c� uL��� ����� �<� � � � �e`gUh����� � ���8���4�N���Wr � ���:�S� R � � ��Q � V:��� � �?`����S�

�¸Å

Page 80: Practical Architectures for Survivable Systems and Networks (Phase

�i] g { h _ ]Ãw"]?\ h rVtk�Fr m rn\ e t|r e ] g _ ts]�r g t e _ c \ mBgih }"[ m ]?� mBc �i] _ [ gihÂm�e u g ]zt h rV} h t hkm�e u¾rV\�w d ] g x c3g�� rV\ _ ] r ml"hkj3l ] g tsr e ] g � �

(�[ � rV\y�irnx®] m�eyh �½{3] g9e � hk�­h t|r g5h \ hkm �Iw"] d ]?\"w�]?\ _ ] c \ mBl ]¶�ir � ] d"g�c3d ] g�mih ]z� c x mil ]¶t c �N] g �¼t|r e ] gx®["\ _ mBhkc \�rVt hkm�e3� (�[ � rV\«�irnx®] m�e�h ��rVtk� c t|r g�j ]?t e rV\«] � ] gij ]z\ m�d"g�c3d ] g�m�eµc x mil ];]z\ mBhsg ];� e � m ] � _ c3� �d tk]�¢£u�rnt mBl�c [ j3lµd r g9mBh _ ["t|r g rn� d ] _ m � c x��irnx®] m�e _ rV\ª}�] _ c \"� h w"] g ]?w²r m t c �5] g t|r e ] g � c x rV}"� mBg r _ mihsc \ �~ ¡ c3g ]�¢�r �­d ts]Vu��i]?] ¹ �¸ VW§u��T 3� ÄK�À�a ts]?r g t e u mBl ] g ]Ir g ] � rV\ eD�­cVg ]�w"] m r h tk]?w d�gic3d ] g9mBh ]z� c xRt c �N] g t|r e ] g � c \;� l"h _ lFmBl ]5� e � m ] � d"gic3d �

] g9mBh ]?� h \ m [ g \µw"] d ]?\�w � � l ]?�i]�r g ]D\ cVm � l"c �&\�]�¢ d t h _ hÂm t e u§x c3gIg ]�rV� c \"� c x w"]?� _ g�hsd�mih {3]D� hk�­d t h _ hkm�eV�

��) � � � ����9, ��� 9�§�"�N, � � � ����� (*�),N�"��9,N�"� �;������¶���

´ ]�x c3g ];r mim ] �Zd�mBh \ jZmic _ r gig9e«c [ m rV\ªr g _ l"hÂm ] _ m [ g ]Frn\"w hkm � hk�­d ts] � ]?\ m r mBhkc \1u�r­{ hÂm rVt d"g ]?t hk�­h \�r g9e� m ] dµh � micZ� r dÃmBl ] c {V] g rVtst �Zh ��� hsc \ g ]� P[ hsg ] � ]z\ m � h \ mBc r�� d ] _ h ± _ ��["}"�i] m#c x mil ] j ]?\"] gih _ g ]� '[ hkg ]��� ]?\ m �#x cVg ��[ g { h {nrV} h t hÂm�e rV\"w hÂm ���i["} m ]?\"w�]?w�r mimigih }"[ m ]z� � � l"h � h �#r m�d"g ]?�i]z\ m r l [ � rn\ª]?\"w�]�r�{ c3g urVt mBl"c [ j3l mBl ]y]�¢ h � m ]z\ _ ] c x _ c3�Zd [ m ] g ��r h w�]?w rV\�rVt e � h � mic§c ts� _ rn\�}�] _ c \ m ] �­d t|r m ]?w mBc rV�i� h � mZh \g ]� '[ hsg ] � ]?\ m �NrV\�rVt e � h �zu�rV\�w��i[�}"�i]� P[�]?\ m t e mBc rV�i� h � m5h \­w"] m ] g��­h \ h \ j¶mBl ]#�i[ _ h ]z\ _ e­c x mil ]�r g _ l"h �m ] _ m [ g ]¶� hkmilµg ]?� d ] _ m¯mBc�mBl ] _ l"c �i]?\ g ]� P[ hsg ] � ]z\ m � �� l ] � r d"d�h \ j¯d"gic _ ]z�i��� l"c ["tkw m r � ] h \ mic r _z_ c ["\ m ]�¢ d ] _ m ]zw�{§[�ts\"] g rV} h t hÂmBh ]z�?u mBl�g ]�r m �?u3rV\"w g�h � � � �

q m � l"c ["tkw­rn\ mih _ hsd r m ] mil ]I\"]?]zw"� c x mBl ]5x®["tst g rV\ j ] c x�]�¢ d ] _ m ]?w­r d"d t h _ r mBhkc \"� rn\"w _ r d rV} h t hkmih ]?� � � l ]\"]z]?w"�½x c3g ]�r _ lÃc x mBl ]#x c tst c � h \ j x®["\ _ mihsc \"rVt _ r d rV} h t hÂmBh ]?� � l"c ["tsw }�]�rV\ mih _ hkd r m ]?w­x g�c3� mBl ] c [ m ��] m ug r mBl ] g&mil rV\yw h � _ c {V] g ]zwªt|r m ] gNh \ mBl ]¶w"]�{3]zt c3d"� ]?\ m uRrV\"wµ� d ] _ h ± _ g ]� P[ hsg ] � ]z\ m �¯w"]z±�\�]?w �

� � ["t mihs� ]?w h rÃx r _ h t hkmih ]?�zu h \ _ ts["w h \ j w�r m r§u { cVh _ ]nu l"hkj3l ��}"rV\"w�� h w mBl P["rVt hÂm�e rV["w hkc u d rn�i� h {3] cVgh \ m ] g r _ mih {V]�{ h w"] c u cVmBl ] gI�­c w"]z� c x g ]�rVt � mBhk� ] j3g r d"l"h _ �?u"q�\ m ] g \�] m¯m ]?tk] d"l�c \ e

� ´5gic rVw _ rV� m rV\"w � ["t mih _ rV� m r d"d t h _ r mihsc \��� q�\ m ] gicVd ] g rV} h t hÂm�e�g ]� '[ hsg ] � ]?\ m �zu h \ _ ts["w h \ j�c3d ]?\µ� m rV\"w�r g w"�� q�\ m ] g ��rV\"w h \ mig r��¼� e � m ] � _ c \�\"] _ mBh { hÂm�e � x c3g ]�¢�r �­d ts]Vu¾� l r g ]?w§� � ] �­cVg�e�� ["t mBhsd�gic _ ]?��� c3g �?ut c _ rVtst e \"] m � c3gi� ]?w � e � m ] � �zu�w hkg ] _ m q�\ m ] g \"] m r _z_ ]?���?uP± g ]��½rVtkts�zu cVg rVt m ] g \"r mBh {3]?t eFh � c tsr m ]zw­rn\"ww g r � r mBh _ rVtkt e�g ]?� migih _ m ]zw�[��i]�~KrV� h \ _ c3�Zd r g�mi� ]z\ m ]?w � [�t mBh ts]�{3]?t ����] _ [ g ]�]?\ _ t|r�{V]?� �

� º�d ] g r mBhkc \�rVt g ]� '[ hkg ] � ]z\ m � � x c3g ]�¢"r �­d tk]Vu hk�­d t h _ r mBhkc \"� c x1]�¢ d ] _ m ]?w�� �'h tkt"ts]�{3]?tk� c x1� e � m ] �rnw �­h \ h � mBg r mBc3g � rV\"w­w"]?� hsg ]zw ts]�{3]zts� c x h \ m ] g r _ mBhkc \1u']�¢ d t h _ hkm w"] _ t|r g r mihsc \ c x�\"]z]?w"�5x c3g g ] �ZcVm ]cVd ] g r mihsc \"��~®] hkmil ] g�c [ m � c x|�¼}�rV\"w c3g { h r mBl ];� m rV\"w�r g wª\"] m � cVgi�'h \ jf� u cVd ] g r mic3g �vx g ]?]D\"]z]?w"��rn�h \Ã] � }�]?w�w"]?w�� e � m ] � � h \ h \�r _z_ ]?��� h }"ts]�t c _ r mBhkc \"�

� �

Page 81: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� � � � � � � � � � � � � � �� � � �

� rV\ e w"]�± _ h ]?\ _ h ]?� h \�]�¢ h � mBh \ j ��["}"� e � m ] � �?u&� e � m ] � �zu�rn\"w+\"] m � cVgi� � �i] gihkc ["�it e l"h \�w"] g�mBl ]«r m �m r h \ � ]?\ m�c x��i[ g { h {nrV} h t hÂm�e3�N¿ ] h w"]?\ mBh x eÃmBl"c �i] mil r m r g ]¶x®["\"w�r � ]z\ m rVtvu�rV\�w g ] _ c3�Z� ]z\"w«� d ] _ h ± _r d"d�gic r _ l ]?� mBc�c {3] g _ c3� ] mBl"c �i] h \�rVw�]� '[�r _ h ]?� �q�\ mBl"h � _ c \ m ]�¢ m u��i[ g { h {nrV} h t hÂm�e�h � _ c \�� h w�] g ]zw h \ mBl ]�} g�c rVw"]z� mDd�c �i� h }"tk]F�i]z\"�i]nu ]z\ _ c3�Zd rV��� h \ j

� ]�rV��[ g ]z� mBc�l rV\"w"tk]�rntst g ]?rVt h � mBh _ mBl"g ]�r m � � h \ _ ts["w h \ j u�x c3g ]�¢�r �Zd ts]nu l r g w��Nr g ] � rVtÂx®["\ _ mihsc \��?u� c x m �½r g ]Z³�rT�&�zu¾r _?_ h w"]?\ m rVt rV\"w � rnt h _ hsc [�� �Zh �i[��i]Vu�]zts] _ mBg�c3� r j \"] mih _ h \ m ] g x®] g ]z\ _ ]nu¾r _ m � c x �¶c w1urV\"w cVmBl ] g;c _?_ [ gig ]?\ _ ]?� mil r m r g ] m�ePd"h _ rVtst e ["\�rn\ mih _ hsd r m ]?w � ¿ ]Z�i]?] ��mic«d"g�c { h w"] r g ]?rVt h � mBh _ r g �_ l"hÂm ] _ m [ g rVt¾} gih w j ];r _ gic �i� mil ] j r d«mBl r m ]�¢ h � m �#}£] m �N]z]?\�~ c \ c \"] l rV\"w �¯mil ] d�g ]?��]?\ m � m r m [�� '[ cc x h \ l ] g ]?\ m t eµh \ _ c3�­d ts] m ] g ]� '[ hsg ] � ]?\ m �zu _ g�hkm ] gih r�uR� m rV\"w�r g w"�?u d�gicVmic _ c ts�zu _ c3�­d�c \"]z\ m �?u�rV\"w©� e ��m ] � �zu�rV\"w ~ c \ mil ] cVmil ] g�l rV\"w �¶mBl ]�\"]z]?w x c3g �i[ g { h {nrV}"ts]­� e � m ] � ��rV\"w4\"] m � c3gi� � mBl r m _ rV\ }�]g r d"h w"t e _ c \�± j [ g ]zw c [ m�c x c »�� mBl ]���� l ]?tÂx _ c3�Z� ] g _ h rVt d"gic w"[ _ m �?u'� d ] _ h ± _ rVtkt eDm r h t c3g ]?w micDd r g�mih _ [�t|r gr d"d t h _ r mBhkc \"� � ¬¯\�x c3g�m ["\�r m ]?t e u � rV\ e � e � m ] � � mBl r m ]�¢ h � m�mBc w�r eFc3g r g ]½x c3g ]z�i]z]?\�x c3g¾mBl ]¯\�]�r g � m ] gi�x®[ m [ g ]Dr g ]Dt hs� ]?t eZmBc }�] h \�rVw�]� '[�r m ]¶x cVg½mBl ]z�i] d [ gid�c ��]?� �� l"h � _ l r d�m ] gZh w"]z\ mih ±�]z��� c3� ] c x mBl ]z�i]y� l"cVg�m _ c3�Zh \ j �zu h \ _ tk["w h \ j«m ] _ l \ c t c3j3h _ rVt½w�]z± _ h ]?\ _ h ]z�

~voP] _ mihsc \��)� � ��rV\"w¶� � ^ � rV\�w cnmBl ] g)d�gic }"tk] � � ~voP] _ mihsc \D� � W ��� aNl r d�m ] g � d"g ]?��]?\ m � g ] _ c3�Z� ]z\"w�r mihsc \"�x c3g&c {3] g _ cV�­h \ j�mBl"c ��]�t hs�Zhkm r mBhkc \"� � aNl r d�m ] g   _ c \ mBh \P[�]?� mil ] h w"]z\ mBh ± _ r mihsc \µrV\"w�rV\�rnt e � h � c x mBl ]w"]�± _ h ]?\ _ h ]?� h \ mBl ] _ c \ m ]�¢ m�c x���[ g { h {nrV}�ts]Ir g _ l"hkm ] _ m [ g ]?�?uPrV\�w d"g ]z�i]?\ m �5� d ] _ h ± _ g ] _ c3�Z� ]z\"w�r mihsc \"�x c3g rVt m ] g \�r mih {3]²� e � m ] � rV\�w \"] m � c3g�� r g _ l"hÂm ] _ m [ g ]?�zuD\�]z� � e � m ] � _ c3�­d�c \"]z\ m �?u�x®["\�w�r � ]?\ m rVt_ l rV\ j ]?� h \ l"c � � e � m ] � ��r g ]Dw�]z{3]zt c3d ]?w�uRrV\"w j [ h w�]?t h \"]?�5x c3gIhs�Zd ts] � ]z\ m r mihsc \ �

� )+( &% �P��� ( � ,�- .0�1�324�5��6¯9, � � � �¶��� ,������

¿�hkmilÃmBl ]�rVt �Zc � m½mBcVm rVt1w"] d ]z\"w"]z\ _ ] c x mil ]D¬ � o ���¶c {V] g \ � ]z\ m u _ gihÂmBh _ rVt h \�x g rn� mBg [ _ m [ g ]z�?u�rV\"w mBl ]d ["}�t h _ ��] _ mBc3g�c \ _ c3�Z� ] g _ h rVtst e rT{nr h t|rV}�ts] c »R� mil ]��¼� l ]ztkx¾� e � m ] � �?u��i["}"� e � m ] � �zu1rV\�w�\"] m � cVgi� �?u�rVtst�i[ g { h {nrV} h t hÂm�e � _ g�hkmBh _ rVt�r d�d t h _ r mihsc \"�Nr g ]¶��] gihkc ["��t e r m�g�h � ���

� ��O�>PQ¸<�STHKJ �Ã= !�=�ST>�� = � � ¢ h � mih \ j�d ] g � c \�rVtÂ� _ c3�Zd [ m ] g)c3d ] g r mBh \ j � e � m ] � ��r g ]N��] g�hsc ["��t e tsr _ � �h \ jFh \Ã�i] _ [ gihÂm�e u g ]?t h rV} h t hÂm�e u'rV\"w l"hkj3l r�{nr h tsrV} h t hkm�eV� ¡ cVgNmBl ] �Zc � m½d r g9m u mil ]?��]�� e � m ] � � _ g rn� lx g ]� '["]z\ m t e ~ � c3� ] mBhk� ]z�¯{V] g�e«d r h \�x®["tst e uR�i[ _ l rV�#� l ]z\²rV\©]?\ mBhkg ]D±�ts]�� e � m ] � h ��� hkd ]zw c [ m �rn\"w c »£] g rVt �Zc � m \ c � c ["\�w �i[ d�d£c3g9m x c3g \"] m � c3g��Ph \ j©c3gD� ["t mBhsd�gic _ ]?��� h \ j"� � h \ h _ cV�­d [ m ] g� e � m ] � �Nr g ] c \"t e r�t hkm�m ts]Nts]?����� c3g �i] � o§[ d ] g _ cV�­d [ m ] g �N} e�mBl ] � �i]?tÂ{3]z� d r e ]?���i]?\ mih rVtkt e t hkmim ts]

��`

Page 82: Practical Architectures for Survivable Systems and Networks (Phase

cVg \ c r mim ]z\ mBhsc \ mic ��] _ [ gihkm�e rn\"w+r�{nr h t|rV} h t hÂm�e _ c \ _ ] g \�� � ¨ h � mBg�h }"[ m ]?w c3d ] g r mBh \ j � e � m ] � �r g ] d r g�mih _ ["t|r g t e {§[�ts\"] g rV}"tk]VuP}£] h \ j�d"gic \"] mic � e \ _ l�gic \ h�� r mihsc \ rV\"w mihs�Zh \ j�d"g�c }"tk] � �?uPw"]�rVwP�t c _ � �zu _ g rn� l ]z�?u&w"]?\ h rVtk� c x��i] g { h _ ]nu¯rV\"wb��] gihkc ["� �­h �i["��] � ~ ¡ c3g ]�¢�r �Zd ts]nuI�i]z] ¹  3^ ÄK�À� � l ]rn}"�i]z\ _ ] c x;r � c � _ rVtstk]?w mig ["� m ]?w d r mil x g�c3� r ["��] gÃmBc r mBg [�� m � c3g�mil'e � e � m ] � h � hkm �i]ztkx�r��] g�hsc ["�Ix r h t h \ jFc x �­c � m � e � m ] � � � ~ � _ l�h ]z{ h \ j ��[ hkm rV}"tk] mBg [�� m ]zw d r mBl � h � _ c \"� h w"] g ]?w h \«o§] _ �mihsc \�  � W � � �¦��º \ mil ]¶� l"c ts]nuR]�¢ h � mBh \ jZcVd ] g r mih \ j � e � m ] � ��r g ]D\ cVm �i] _ [ g ]FrV�&w"]zt h {V] g ]?w � ]z{V]?\� hÂmBl {3] g�e _ r g ]�x®["t h \ hÂmBh rnt h�� r mBhkc \ rV\"w _ c \§± j [ g r mBhkc \ � rV\"r j ] � ]?\ m u � rV\ e {P["ts\"] g rV} h t hÂmBh ]?�r g ] � mBh tktNt hs� ]zt e²mBc²g ] � r h \ � � l ] aNc3�Zd [ m ] g���� ] gij ]?\ _ e p¯]z� d�c \"��] � ]�r � ~ a½� p � ��aNcPc3g �w h \�r mihsc \ a ]?\ m ] g ~ mil ] a½� p � h � d r g9m�c x mil ]�o c x m �½r g ] � \ j3h \"]?] gih \ j q�\"� mBhkm [ m ]Fr m¶a r g \"] jVh ]��� ]?tst c \ � �i]z] lfm�mBd �¦¥3¥��I�I� � _ ] g�m��·c3g�j'� rV\�w cVmil ] g ��[ _ l c _ h rVt c3g�j rV\ h�� r mihsc \��²~ ��[ _ l rV� mBl ]��r�� g ]z\ _ ]��� h {V] g��­c3g ] a q�� a u l'm�mBd �¦¥3¥��I�I� � _ h r _ �·c3g�j ¥ �¯d�gic { h w"]�r�� m ]�rVw e ³ c � c x g ] d£c3g9m � c \{P["tk\"] g rV} h t hkmih ]z�½rV\"wñ�¢§]z��~®� hÂmBl ] �Zd"l rn� h � c \ mil ]¶t|r m�m ] gIg r mBl ] g½mBl rV\ mil ]�x c3gi� ] gB������g ]?r m ] g] �­d�l rV� h � c \ ³Rr��&� h � d"gic { h w"]zw } e mBl ] ´ [ j � g r w h � mBgih }"[ mihsc \b~ ´ [ j � g r §¤�\�] m � d r _ ] �·c3gij'� u� l�h _ l4j ]?\"] g rVtkt e²j ] m � mil ] � \ c �&tk]?w j ] c x½{P["tk\"] g rV} h t hkmih ]?� c [ m t c \ j }£]�x c3g ] mBl ] a½� p � u rn\"w� l�h _ lbh �Z� h w"]?t e�g ]�rVw+} e mil ]ª["\"w�] gijVgic ["\�w _ g r _ � ] g _ c3�Z� ["\ hÂm�e3� o§]z]©rVts� c � � ´ [ j � g r lfm�mBd �¦¥3¥��I�I� � \ m }"[ jnmBg r � _ cV� ¥�x c3g½¿�h \"w c �&� � � g ]zt|r m ]?w d"g�c }"ts] � � �

� ��>'Q"�£>'Q�= � � l ] � m r m ] c x mBl ]�r g�m � hkmBl g ]z� d ] _ m;mBc ��] g {3] g � h � c \"t e rµt hÂmim tk]�}£] mim ] g�mil rV\ x cVgcVd ] g r mih \ j � e � m ] � � h \ j ]z\"] g rVt � o e � m ] � �I��[ _ l rV�N± g ]z�NrVtstk�½r g ] m�ePd"h _ rVtst e {P["ts\"] g rV}�ts] mic��­h �9�[��i] c3g�mBc¶d ] gi�Zhkm�mBh \ j w�rV\ j ] g�c ["��]z{3]z\ m � mic¶d rV�i� mBl�gic [ jVl uPrV\"w h \Zr _ m [�rVt hkm�e;� r eFmil ] � �i]ztk{3]z�}�] g�h � �'e � h \ d r g�m }£] _ rV[��i] c x mil ] h tstk["� hkc \ mBl r mDmBl ] e � c tÂ{3] r�t|r g�j ] gDd£cVg�mBhkc \ c x mBl ] �i]��_ [ gihÂm�e d"gic }"ts] � mBl rV\ mBl ] e r _ m ["rVtst e w c u&rn\"w h \ d r g�m }£] _ rV["��] mBl ] e mBl ] � ��]?tÂ{3]?� � r e }�]³�rT�5]?w � ¡ h ts]F��] g {V] g �FrV\"w rV[ mil ]?\ mih _ r mBhsc \���] g {3] g ��r g ]Z� mBh tst¾\ cVm rVw"]� '[�r m ]�x c3g�mBl ]Z\"]z]?w"� c x_ gihÂmBh _ rVtÂ�¼�i[ g { h {nrV} h t hkm�e r d"d t h _ r mBhkc \"� �

� �yH =zSTQ�H � ��ST>�% :�>fST>'Q¸E��R>PJ�>PE��)= �)< � ��O*= !�=zST>�� = � o§[ g { h {nrV}"ts]­]?\f{ hsg�c \ � ]?\ m ��w"] d ]z\"w_ gihÂmBh _ rVtst e;c \ mBl ]#r�{nr h tsrV} h t hkm�eDc x£x r _ h t hÂmBh ]z� mBl r mNd ] g x c3gi� g ] j [�t|r g�mBg ["� m � c3g9mBlfe }"r _ � [ d � l ]z\§�]�{3] g rV\ e _ g�hkmBh _ rVt�� e � m ] � � m r m ] h \�x c3g�� r mihsc \ _ l rV\ j ]z�?u�rV\"w g r d"h w mBg ["� m � c3g9mBlfe g ] _ c {V] g9e� l ]?\"]�{3] gNg ]� '[ hkg ]zw � q�\ l�hsj3l t e�l ] m ] g�c3j ]z\"] c [��N]?\f{ hsg�c \ � ]?\ m �zu mil ]¯}�r _ � [ d � e � m ] � � � ["� m }�]_ c3j \ h�� rV\ m�c x mil ] h w hsc � e \ _ g rV� h ]?� c x mBl ] h \"w h { h w"["rVt�� e � m ] � ��rV\"w��i] g {3] g ��x c3g � l"h _ l }�r _ � [ drn\"w g ] migih ]z{nrVt � [�� m }£] d ] g x c3gi� ]?w �

� � !�=zS�> �4H y< ��S¸:)>PJ£STH 3<�STH E�J � o c3� ] c x mil ] �Zc � m ��] g�hsc ["���i] _ [ g�hkm�e w"]z± _ h ]z\ _ h ]?� h \�["�i] g#c3d �] g r mih \ j � e � m ] � �zu£��] g {3] g �?u£rV\"wµ\"] m � c3g�� � h \f{ c tk{3] mBl ]Dtsr _ � c x¾rVw"]� '[�r m ]�rV[ mil ]?\ mih _ r mBhsc \4~ h \§�_ ts["w h \ j rV[ mil ]?\ mih _ r mBhsc \ c x�["�i] g �zu�� e � m ] � �?u�rV\"w­�i["}"� e � m ] � � � rV\"w mBl ]¯t|r _ ��c x mig ["� m ]?w d r mil �x g�c3� ["��] g � mBc � e � m ] � ��rn\"w4x gicV� � e � m ] � � mBc [��i] g � � q�\ rVt �Zc � m rVtkt _ c3�Z� ] g _ h rVt�� e � m ] � �zumil ] g ]¯r g ]&rVt �­c � m \ cDj [�r g rV\ m ]z]?� mBl r m r¶[��i] g�h � h \ m ] g r _ mih \ j � hÂmBl�mBl ] h \ m ]?\�w"]?w­� e � m ] �µ��º \�]c x mil ] �­c � mZhs�Zd£c3g9m rV\ m rnw�{nrV\ _ ]z� h \ c {V] g _ c3�Zh \ j ��]z{3] g rVt c x mBl ]yw"]�± _ h ]?\ _ h ]?�Z\ cVm ]?w l ] g ]h \f{ c tÂ{3]?��rª��] g�hsc ["��]�» cVg�mFmic©hs�Zd"gic {3] mBl ]yrV[ mBl ]z\ mih _ r mBhkc \ d"gic _ ]z�i��rV\�w mil ] d ] g {nrV� h {V]?\"]z�i�� hÂmBl � l"h _ l hÂm�h ��["��]?w mBl"g�c [ j3l�c [ m�� o e � m ] �­h _ rV[ mBl ]?\ mBh _ r mihsc \ rV\"w h \ m ] j3g�hkm�e4c x g ]?� c [ g _ ]� rV\�r j ] � ]?\ m r g ]DrVts� c _ c \"� h w"] g ]?w h \�o§] _ mihsc \�  � W � W �

� µ>fS�C;ERQ � HKJ �­O)Q¸E�STE&3E�LK= � � l ]N{nr gihkc ["��q�\ m ] g \"] m d"gicVmic _ c ts� r m w h »£] g ]?\ m tsr e ] g � h \ mBl ] d"g�cVmBc �_ c t�� m r _ � ~ ] �Áj"� u ¡ �&� u � ]?tk\"] m u"rV\"wµo ���&� r m5mBl ]�r d"d t h _ r mihsc \­t|r e ] g u�¬#¨ � r m½mBl ] mBg rV\"� d�c3g9mtsr e ] gB� rV\"w mil ] hkg&hs�Zd ts] � ]z\ m r mBhkc \"�¶~®] �·j"� u =z>§J'%'�4<�H L rV��rV\ hk�­d tk] � ]?\ m r mBhsc \ c x o ���&� � r g ]x cVg¾mBl ] �Zc � m d r g�m ��] g�hsc ["��t e w"]z± _ h ]z\ m � l ]z\ hÂm _ c3� ]?� mic �i] _ [ gihÂm�e uPrV\"w��5]�r � � hÂmBl�g ]z� d ] _ m�mic

� �

Page 83: Practical Architectures for Survivable Systems and Networks (Phase

g ]?t h rV} h t hÂm�e3� ¬�\§x c3g�m ["\�r m ]?t e u mil ] e r g ]D{3] g9e � h w"]?t e [��i]?w�u�w"]?� d"hkm ] mBl ] hsg�j t|r g�h \ j �5]�r � \"]z�i�i]z� �� r gihsc ["�5��[ _?_ ]?��� c3g � mBc;mil ]#q � q�\ m ] g \"] mId"gicnmBc _ c tR�i[ hkm ] l r�{3]�}�]?]z\ d"gicVd£c ��]?w1u�rVt mil"c [ jVlZmil ] hkgg ]�rVt h � mBh _ � mig ]z\ jVmBl �¶rV\"w©�N]?r � \"]?���i]z� g ] � r h \ mic }£]���]?]z\ � q � o ��a ~ lfmimid �À¥V¥��I�I� �Áh ] m x �Ác3g�j'��h �h \ m ]?\�w"]?w mBcµd"gic { h w�]Z]z\"w§� mBc �¼]?\"w ]?\ _ g�ePd�mBhkc \ c {V] g¶mBl ]Zq�\ m ] g \"] m ~®\ cVmDd"gic { h w�]?w h \�q � � ] g �� hsc \­� � u�rV\"w � c3� ] d ]?] g rV[ mBl ]?\ mBh _ r mihsc \ª~ }"[ m \ cVm [��i] g rV[ mBl ]?\ mBh _ r mihsc \ � rV\"wÃ� c3� ] h \ m ] j3g�hkm�e~®\ c \ _ g�ePd�mic3j3g r d"l"h _ � ]?�i�ir j ]­rV[ mil ]?\ mBh _ r mihsc \ ��� � r g�hsc ["���5]�r � \"]z�i��]?� c xIq � o ��a l r�{3]­}£]z]?\rn\�rVt e � ]?w ~®] �·j"� u ¹ W3� Ä|����º {3] g rVtktvuRq � � ] g � hsc \ª� h � h \ m ]?\�w"]?w mic�d"g�c { h w"]Fr �­cVg ] gic }"[�� m �i] m#c xd�gicVmic _ c ts�zu rV\"w h \ _ tk["w"]z�;q � o ��a#� ¨ c3� r h \ � r � ]Ão e � m ] � o§] _ [ g�hkm�e ~ ¨ � o"o �5aI�Dd"gicVmic _ c ts�l rT{V]©rVtk� c }�]?]z\ d"gic3d�c ��]?w1u&� hkmil r d ["}�t h _ � � ] e�h \�x g rV� mig [ _ m [ g ] h \�w"] d ]?\"w�]?\ myc x mBl ]©¨ � o'�w c3� r h \ d ["}"t h _ � � ] eµh \�x g rV� mBg [ _ m [ g ] � � �Zc \ j hÂm � cnmBl ] g�� \ c �&\²{P["tk\"] g rV} h t hkmih ]z�?u�¨ � o"o �5a h �{P["tk\"] g rV}"tk] mBc _ c3�Zd"gicV�­h �i]?� c x hÂm �½rntstÂ� d£c �5] g x®["t l"h ] g r g _ l"h _ rVt g�c§cnm�� ��t mBl�c [ j3l x®[ g�mBl ] g � m ["w ern\"w g ]z±"\"] � ]?\ m r g ]�\"]z]?w"]zw1u mBl ]z�i] d"gicVd£c �irVts����]?] � mBc }�]­r hs� ]?w²r m¶c \�t e ry� � rntst d�c3g9mBhsc \c x mil ]��i] _ [ g�hkm�e©d�gic }"tk] � u1rV\�w r � [ _ l � � rntsts] g�d�c3g9mBhsc \ c x mBl ] c {3] g rVtkt �i[ g { h {nrV} h t hÂm�eyd"gic }P�tk] �µ� ¡ c3g�mil"c �i]Z]?\f{ hsg�c \ � ]?\ m � h \²� l"h _ l ±�¢§]?w _ c3�Z� ["\ h _ r mihsc \ªx r _ h t hkmBh ]?�#r g ]Z\ cVm�d£c �i� h }"ts]cVg w"]?� hsg rn}"ts]nu mBl ] g ]� '[ hsg ] � ]?\ m ��rV\"wyx r _ h t hÂmBh ]z��x cVg ��] _ [ g ]nu g ]?t h rV}"tk]Vu�rV\"wµ�i[ g { h {nrV}"ts]�� hkg ]?tk]?���_ c3�Z� ["\ h _ r mihsc \"�#r g ]�� mBh tkt h \ mil ] hkg�h \�x rn\ _ eV� � rV\ e²d"gic }"ts] � � g ] � r h \1u��i[ _ l rn� gic }"[�� mD� ] e� rV\�r j ] � ]?\ m��

� ��Q"!�O�STE �RQ�<�O¾:)H O)Q¸E�STE&3E�LK=F<"J %+>�����>�% %)H J'��= � �#t mil"c [ jVl � mBg�c \ j _ g�ePd�mBcVj3g r d�l"h _ rVt j3c �g�hkmil"� �#]�¢ h � m u mBl ] hsg�hk�­d ts] � ]?\ m r mBhkc \"� m ]?\"w mBc }�]F{P["ts\"] g rV}�ts] mBc _ c3�­d�gic3�Zh ��] ��´ ] _ rV[��i] c x¬ � o � ��c {3] g \ � ]?\ mFd�c t h _ h ]?� g ] j r g w h \ j � migic \ j _ g�ePd�mic3j3g r d"lfe rn\"w4}�] _ rV["�i] c x mBl ] h \ l ] g ]?\ mg�h � � �5rV��� c _ h r m ]?w�� hkmil�� ] e � g ] _ c {V] g�e � _ l ] � ]z�?u mil ]¯["�i] c x _ g�ePd�mBcVj3g r d�l'eZh � x r g tk]?�i� d"g ]z{nrVts]z\ mmil rV\ h � \"]?]zw"]?w mic ��[ d"d�c3g�mN� ]?rV\ h \ j x®["t"��] _ [ gihÂm�e3� ~ ¡ c3g ]�¢�r �Zd tk]Vu'�i]z] ¹ ��u§ §uP�V��u§^n�f� Äv�¦� � l ] g ]r g ];��[ gid�gih � h \ j t ey� rV\ e �Nr e � c x } g ]?r �'h \ j _ g�ePd�mic3j3g r d"l"h _ ] � }�]?w"w h \ j �¯� hkmil"c [ m ]�¢ l rV["� mBh {3]� ] e �i]�r g _ l ]z�;rV\�wª� hkmBl�c [ m } g ]�r �'h \ j mBl ]�rnt j3c3g�hkmil"� � �i[ _ l rV� � rV["t�° c _ l ] g�� � mihs�Zh \ j r m �m r _ � � ¹ �¸�V� Ä uI° c _ l ] g�� �­w h »£] g ]?\ mBh rVt d£c �5] g rn\�rVt e ��]?�©~ p h � � � ¡ c3g [ � u5{ c ts[ � ] ����u h �i�i[�]ª�3X�ulfm�mBd �¦¥3¥ _ r m tk]?�i� � \ _ t � r _ � [ � ¥Vp h � � � ¥§�T� � �3X �ÁlfmB� t � u c3g�mBl ]�x rV["t m � h \ � ] _ mBhkc \ m ] _ l \ h P[�]?� c x½�#\�w"] g �� c \ rV\"w °�[ l \ ¹ �¸� Ä rV\"w cVmBl ] g � ¹ ^V� ÄK� ( c �N]�{3] g uN]�{3]z\�} g [ m ]��¼x c3g _ ]yr m�m r _ � �Zr g ] }£] _ c3�Zh \ jx®]?rV� h }"ts]nuNrn�­w"] �­c \"� mig r m ]?w+} e mBl ] � ts] _ migic \ h _ ¡ g�c \ mBh ] g ¡ c ["\"w�r mBhsc \�� d£c \�� c3g ]?w � r _ l"h \"]Vu¨�]z] d4aNg r _ � ¹ �TXf  Ä � � l"h _ l4h � _ r d rV}�ts] c x�±�\"w h \ j ¨ � o � ] e �zu c \ mBl ]�r�{3] g r j ]�rnx m ] g � ["� mrZx®]z��w�r e � c x�]�¢ l rV["� mBh {3]��i]?r g _ l ~ r m�mBl ] _ c � m�c x�ts]z�i� mil rV\²r '[�r g�m ] g�c x5r �Zh tkt hsc \µw c tstsr g �mic }"[ h tsw mBl ] h \ hkmih rVtR¨�]z] dyaNg r _ ��� r _ l"h \"] ��� � c3g ] g ] _ ]z\ m t e u mBl ];�T�3�3�Fp�o§� ¨ � o aNl rVtstk]?\ j ]�NrV�I} g�c3� ]z\ h \Ãts]z�i� mBl rV\�^n� l"c [ g �&} e ¨ h � mBgih }"[ m ]?w aNg r _ � uRr _ c \"� cVg�mBh [ � c x � rV\ e w h »£] g ]z\ m_ c3�Zd [ m ] g �«~ h \ _ tk["w h \ j ¨�]z] d�aNg r _ � u½� l"h _ l+l r d"d ]?\"]zw mBc }£] mBl ] � r _ l"h \�] mil r m r _ m [�rVtkt ew h � _ c {3] g ]?w mBl ] aNl rVtkts]z\ j ] � ] e u�rnx m ] g r g rV\"w cV� ��]�r g _ l²c x c \"t e � � c x mBl ] � ] e � d r _ ] � ¨ h �9�migih }"[ m ]zw aNg r _ �yhkm �i]ztkx l rVwµ]�¢ l rV[�� m ]zw²^VW � c x mil ] � ] e � d r _ ];r m&mil r m&mBhk� ]nu h \"w h _ r mBh \ j;mBl r mmil ]Ãr jVj3g ] j r m ] d£c �5] g�c x mil ] � e � m ] � � cVmBl ] g;mil rV\ ¨�]?] d aNg r _ � �½rn� _ c \"� h w"] g rV}�t e j3g ]?r m ] gmil rV\­¨�]?] dÃaNg r _ �ZhÂm ��]?tkx ��� � l ] � r g�j3h \"rVt _ c � m5c x�¨ h � migih }�[ m ]zw aNg r _ ��h � mBl ] g ]�x c3g ]¯]?���i]z\ mih rVtkt e� ] g�c u"}�] _ rn["�i] hkmNh � � ] g ]?t e ["� h \ j x g ]?] _ e _ ts]?�½x g�c3� d r g�mih _ hkd r mih \ j � e � m ] � �¯rV\ e � l ] g ] c \ mBl ]q�\ m ] g \�] m��o _ l \"] h ] g rV\"w � ["w j ] ¹ Wf�VX Ä � l rT{V];["\ _ c {3] g ]?w²rn\«rV� mBc [�\"w h \ j {nr g�h ] m�e c x ]zts] � ]?\ m rVt1³Rr��&� h \� h _ g�c � c x m � � hk�­d ts] � ]?\ m r mBhkc \ c x mil ] � c3h \ m � mic � � c3h \ m � ["\"\"]zt h \ j � gicVmic _ c t¯~ � ���&� � u c \"t e r

� �@21>1=�!+B& �:35)��b,56T3F: �1+ �*� ! UX30�FUX35%<;��)b=)*,21��;�/?,� !/435&7� � �1�L�QK�/?,� �:35)*� ,56 � ����35;�#.� � �1���^] & �^_1_ � ����/:30�*�X,)�35'1����&*�*+B-�,/LI � �� � �%�'H35+B-���>.�*�:30�V+ �"+B&!�Y,&*&�+B81'B�9�*,a81)*+B/1=[>1,Q !/A�*�1�$�Q/L�*+B)��5&J/L����)�/?���V+B/@358Y,2?� � � -�+B/�2?�*�Q&Q#

� �

Page 84: Practical Architectures for Survivable Systems and Networks (Phase

x®]�� c x)� l"h _ l�l r�{V];r d�d r g ]z\ m t e }£]z]?\y±�¢§]?w �º \�r � [ _ l } gic rnw"] g x gic \ m u�o _ l \�] h ] g ¹ WV�f� Ä ]�¢"r �­h \"]?� � rn\ eZc x mBl ] _ l r g r _ m ] gih � mih _ ³�rT�&� mBl r mg ]?��["t m x g�c3� hk�­d"g�c3d ] g t e ] � }�]?w"w"]zw _ g�ePd�mBcVj3g r d�l'eV�

� ��E��4O ��S�>PQ�@ 3E���� � J)H 3<§S¸H E�JÃH J'�vQ�<"=zSTQ � VS"�)Q¸> � � l ] q�\ m ] g \"] m u gic [ m ] g �?u�q � rVw"w g ]?���i]z�?ufw c �� r h \�\�r � ]I�i] g {3] g �?u�\"] m � c3gi��h \�x c3g�� r mihsc \;�i] g { h _ ]z�?u�rV\"w cVmBl ] g h \�x g rV� mig [ _ m [ g rVt _ cV�­d�c \"]z\ m �r g ] mil ] � �i]ztk{V]?��{P["ts\�] g rn}"ts] mBc �Zh ��["�i]�rn\"w©r _z_ h w�]?\ m rVt)x r h tk[ g ]z� �¯¿�hsg ]zts]z�i� _ c3�­� ["\ h _ r mBhkc \"�r g ] d r g�mBh _ ["tsr g t e {P["ts\"] g rV}�ts] mic _ c3�Zd"gic3�Zh ��] � q�\ mBl ]yrV}"�i]z\ _ ] c x _ g�ePd�mBcVj3g r d�l'e u _ c3�Zd"gic ��Zh ��]?� c x _ c \§±�w"]?\ mih rVt hkm�e rV\"w h \ m ] j3g�hkm�e­g ] d"g ]z�i]?\ m ]z\ c3gi�Zc ["� gih � � � ��� {3]?\ h \ mBl ] d"g ]z�i]?\ _ ] c x� mBg�c \ j rV\"w �5]?tktÂ�¼] � }�]?w"w�]?w _ g9ePd�mBc3jVg r d"lfe u�w"]?\ h rVtÂ� c x|����] g { h _ ]�r mim r _ � �&r g ]�]?rV� e­mBc _ r gig9e�c [ m~®] �·j"� u�� hkmil ]zts] _ mBg�c3� r j \"] mih _ h \ m ] g x®] g ]?\ _ ] ���

� � <"Q %�C;<"Q¸> � ¿�hkmil mBl ] d"g ]z{nrVtsrV\ _ ] c xIp&q9o a ~ g ]?w�[ _ ]zw h \"� mBg [ _ mBhkc \��i] m _ c3�Zd [ m ] g � ��l r g wP��Nr g ]yr g _ l"hÂm ] _ m [ g ]?�zu � c3� ] c x mBl ]Ã�i] _ [ gihÂm�e � ] _ l rn\ h � � � l r�{V]Ãw h �ir d"d ]�r g ]?w x gic3� m�ePd ]z� c xd�gic _ ]?��� c3g w�]?� hkj \"� mil r m¶c \ _ ] d r h w©�i] g�hsc [��¶r mim ]?\ mBhkc \ mBc ��] _ [ gihkm�eV�F� {3]z\ h \ _ rV��]?� h \«� l�h _ lw c3� r h \²�i] d r g r mBhsc \ h � d"gic { h w�]?w h \ mBl ] l r g w��Nr g ]nu c3d ] g r mBh \ j � e � m ] � � m ]?\"w \ cVm�mic ["��] hkm]�»�] _ mih {3]zt eV� o hs�Zh tsr g t e un� c3� ] c x mBl ] �Zc3g ]�rVw�{nrV\ _ ]?w�rV\"w d£c �5] g x®[�t m ] _ l \ h '["]?�Nx cVg5g ]?t h rV} h t hkm�ern\"w�x rV[�t m¯mBc tk] g rn\ _ ]�r g ] m�ePd"h _ rVtst e \ cVm ["�i]zw h \ _ c3�Z� ] g _ h rVt l r g w��Nr g ] � q�\ mBl ]�� m rn\"w§�rnt c \"]d ] g � c \"rVtÂ� _ c3�Zd [ m ] g � c3g tsw1u c _?_ rV� hkc \�rVt l r g w��½r g ] _ g rV� l ]?�yr g ]ª\ cVm _ c \�� h w�] g ]zw hs�Zd£c3g9m rV\ m]�{3]z\ m � � ¬�\�x cVg�m [�\�r m ]zt e u��i[ _ l�l r g w§�½r g ] h � c x m ]?\yx c ["\"w h \ _ gihkmih _ rVt�� e � m ] � � �

� M�>P<"L @�S¸H��4> �4E�J)H®STERQ�H J'�b<"J %�<�J)<"L !�=?HK= � � m;d"g ]z�i]z\ m u g ]?rVtÂ� mBhs� ]�rV\�rnt e'mBh _ ]z\f{ hkgic \ � ]z\ m �m ]?\"w mic }£]Ã� d ] _ h rnt d [ g�d£c ��] � x c3g ]�¢"r �­d tk]Vu�x c _ ["� h \ j©c \ r mim ] �­d§m ]?w ]�¢ d t c3hÂm r mihsc \"� c x�rx®]�� � \ c �&\4��] _ [ gihÂm�e {§[�ts\"] g rV} h t hÂmBh ]z� c3g rÃx®]z� � \ c �&\ mBl�g ]�r m � mBcyg ]zt h rn} h t hkm�e rV\"w r�{nr h tsrV} h t �hÂm�e3� q m�h �;w h _ ["t m¶mBc w�r e�mic«d"g�c { h w"] g ]�rVt � mihs� ] �­c \ hkmBcVgih \ j rn\"w rV\"rVt e � h �D� hÂmBl g ]?� d ] _ mFmic��["� d�h _ hkc ["�D}"[ m ["\"� d ] _ h ± _ ]z{3]z\ m �?u rn\"w4� hkmil4g ]?� d ] _ mFmBcµmBl ]­� hk� ["t m rV\"] c ["�¶�Br mih �9x r _ mihsc \ c x� ["t mihsd tk] g ]� '[ hsg ] � ]?\ m � � q m�h ��rnts� c w h _ ["t mFmBc²l rn\"w"ts] l�hsj3l t e w h � mBgih }"[ m ]?w ]?\f{ hsg�c \ � ]?\ m �zu� l ] g ] _ c3g�g ]zt|r mihsc \ c x�w h »£] g ]z\ m rV\�rnt e'mBh _ g ]?��["t m �­� c ["tsw�}£]�rVw�{nrV\ m r j ] c ["� � ¡ [ g�mil ] g��­cVg ]Vumil ]�rV}��i]?\ _ ] c x � ]�rV\ h \ j x®["t)rV[ mBl ]z\ mih _ r mBhkc \©rV\"w²r _?_ c ["\ m rV} h t hÂm�e�� r � ]?� hÂm {3] g�e w h _ [�t m#micw�] m ] gi�Zh \"] mil ]¶� c [ g _ ] c x �i] _ [ g�hkm�eyh \ mig ["� hsc \�� �

� ��O�>PQ¸<�STH E�J�<�L)O)Q¸< VS¸H�3> � � mil"g ]?rVw mBl r m g ["\"� mBl�gic [ jVl"c [ m mil"h � g ] d�c3g�m h � mBl r m j3cPc w�� e � m ] �r g _ l"hÂm ] _ m [ g ]�rV\�w j3cPc w­w"]z{V]?t cVd"� ]z\ m½d"g r _ mih _ ]#r g ]�\ cVm ]?\ c [ j3l1��º�d ] g r mBhsc \�rVt d"g r _ mBh _ ] h �5rV\]z\ c3g��­c [��I� c [ g _ ] c x d"gic }�ts] � � �

� ) � � �¶��� ,������ 9, ����� �',����5�R(*�¾�"9�5,��',��������'�"�R�����"�����

� l ] d"g ]z{ hsc ["�F�i] _ mihsc \ c [ m t h \"]?��\'[ � ] gic [���w"]z± _ h ]z\ _ h ]?� h \ _ c3�Zd [ m ] g � e � m ] � �ZrV\�w h \ \"] m � cVgi� �h \ j � c x m �½r g ] � ( c �N]�{3] g u � c3� ]­x®[�\"w�r � ]?\ m rnt d"g�c }"tk] � � mig rV\"� _ ]z\"w w"]z± _ h ]z\ _ h ]?� h \4� e � m ] � ��rn\"w\"] m � c3g��'h \ j � c x m �Nr g ] � � d ] _ h ± _ rVtkt e u mil"c �i] g ]zt|r mih \ j�mBcZmBl ]�["\"w"] g t e§h \ j�h \�x c3g�� r mihsc \ h \�x g rn� mBg [ _ �m [ g ] ��¿ ]�r g ]�}�] _ c3�­h \ j _ g�hkmBh _ rVtkt e w"] d ]z\"w"]?\ m�c \ mil ]�q�\ m ] g \�] m u£rV\"w�r g ]�t hs� ]zt e­mBc }£]D]z{V]?\ �Zc3g ]w"] d ]z\"w"]?\ m�c \y� l r m ]�{3] g ��[ _?_ ]?]?w�� hkm?�¬�\§x c3g�m ["\�r m ]?t e u mBl ]yq�\ m ] g \"] m�l rn�Z}�] _ c3� ]yrV\ ]?\ c3g��­c ["���i]?tÂx|� d ] g�d ] m [�r mih \ j©cVgij rV\ h � � c x hkm �

c �&\ � � hkmBl \ c _ c3l ] g ]?\ m�� rV\�r j ] � ]?\ m uR\ c c {V] g rntst _ c \ mBg�c tvu�rV\�w©rVt �Zc � m \ c�c �&\"] g � l"hkd } e rn\ e\�r mihsc \"rVt c3g _ c3g�d£cVg r m ]Z]z\ mBhkmih ]z��~®]�¢ _ ] d�m�h \�\ c \"w"] �­c _ g r mBh _Z_ c ["\ mBg�h ]z� ��� q m �D]�¢ h � m ]?\ _ ] h �;rnt �Zc � m

� �

Page 85: Practical Architectures for Survivable Systems and Networks (Phase

mBcnm rVtkt e ["\ g ] j [�t|r m ]?w1ufrn\"w hkm¾h � g ["\ c \ mil ]N³ e�h \Fr#� migihs�'h \ j t e [�\ d"gic x®]?�i� hsc \"rVt§�Nr e3� ´ ] _ rV["��] mBg r _� r e }£] gic [ m ]zw«r g } hkmig r g�h t eZmil"gic [ j3lyd£cnm ]?\ mih rVtkt e ["\ mBg [�� m � c3g�mil'e rV\"wµ["\ g ]?t h rV}"tk]�\ c w"]?�zu g ] mBg�ePh \ jc {3] g rVt m ] g \�r m ] g�c [ m ]?� h �Dr m;d�g ]?��]?\ mFm�ePd"h _ rVtkt e«mil ]�}�]?� m�mil r m _ rV\ }£]Zw c \�]­� l ]z\ d"gic }"ts] � �Dr g ]]�¢ d ] g�h ]?\ _ ]?w � ´ [ mÃmBl r m r d"d"g�c r _ l h ��{P["tk\"] g rV}"ts] mic � rV��� h {3]©w"]z\ h rVt � c x|�¼�i] g { h _ ]©r mim r _ � � � q¼x;r{ hkm rVt j r m ]z�Nr e�h ��w c �&\1uPrV\Z]?\ mBhkg ]I]z\ m ] g�d"gih �i] � r e }�] c » mil ]&q�\ m ] g \"] m?� q�\ j ]z\"] g rVtvu3�5]�r � \�]?�i��]?� h \mBl ] h \�x g rV� mig [ _ m [ g ]½}£] _ c3� ]N�5]�r � \"]z�i��]?� h \ mBl ] _ c3�Zd [ m ] g � e � m ] � ��rV\"w�\"] m � cVgi�'h \ j � c x m �½r g ] � ¡ c3g]�¢�r �Zd tk]Vu mBl ]½x®["\"w�r � ]?\ m rVt"w"]�± _ h ]?\ _ h ]?� h \�\"] m � c3g��Ph \ jDd"gicVmic _ c ts�¾\ cVm ]zw h \Zo§] _ mBhkc \�� � �&rn»�] _ m \ cnm� ["� m t c _ rVt�\"] m � c3g�� �FrV\"w4]z\ m ] g�d"gih �i]�� h \ m ] g \"rVt5\�] m � c3gi� �?u�}�[ m rnts� cymBl ]­q�\ m ] g \"] m ��mBl ] e r g ]Zt hk� ]zt emBc4l rV["\ m rV\ e x®[ m [ g ] h \§x c3gi� r mBhkc \ h \�x g rV� mig [ _ m [ g ]?� [�\"ts]z�i� g rnw h _ rVtst e �i[ d ] g �i]zw"]?w � aNc \f{3] g ��]?t e u�5]�r � \"]z�i�i]z� h \ _ c3�Zd [ m ] g � e � m ] � �ZrV\�w \"] m � c3gi�'h \ j � c x m �Nr g ] _ rV\ g ]z�i["t m�h \4�5]�r � \�]?�i��]?� h \ mBl ]h \§x c3gi� r mBhkc \ h \�x g rn� mBg [ _ m [ g ] � rn»£] _ mBh \ j�m ]?tk] _ c3�­� ["\ h _ r mBhkc \"�NrV\"w d£c �5] g w h � mBgih }"[ mihsc \Ãrn�&�5]?tkt �

� )�� � ������� � � �¶��� ,������

� � !�=zS�> � %�>���>§L®ERO � >§J�S�O Q¸< VSTH 3> � � l ]D� e � m ] � �¼w"]z{V]?t c3d"� ]?\ m¯d"g r _ mBh _ ] h \ mBl ]¶¬ � o ��h �½\ cnmjVc§c w1uPrV\"w h \ � rV\ e _ rV��]?� _ c ["tsw­}£] _ rVtkts]?wZw h �BrV� mBgic ["� ����c§c w�� e � m ] � ]z\ j3h \"]?] gih \ j rV\"w­� c x m ��Nr g ]D]z\ j3h \"]?] gih \ j­d"g r _ mih _ ] h �&]�¢ mBg ] � ]?t e g r g ] � � rV\ e ¬ � o �£�¶c {V] g \ � ]z\ m � e � m ] � � l r�{3] l rVwmic }£]DrV}�rn\"w c \"]zw ~®] �·j"� u mBl ] ¡ ��� � hsg �p c [ m ] � g r _ aNc \ migic t)o e � m ] � u mil ] ¡ ´ q5±"\ j ] g�d"gih \ m� e � m ] � u�rV\"w mBl ]¯qp#o � r�¢ o e � m ] � � c w"] g \ h�� r mihsc \Z]z» c3g�m � r�x m ] g mBl ]#]�¢ d ]?\"w hkm [ g ] c x�} h tkt hkc \"�c x w c tstsr g � � � l ] g ] _ c3g w c x5� m r m ]?�¶rV\�w d"gih {Vr m ] _ c3gid�c3g r mBhsc \"� h ��\ cVm�� [ _ l }£] mim ] g ~ ] �Áj"� u mBl ]a rnt h x cVg \ h r�o m r m ]�� h w"]I��[ mBc3� r m ]?w aNl"h tkw­o§[ d"d�c3g�m o e � m ] � � \ c �&\�rV� mBl ]�¨�]?rVw"}�]�r m ¹ � c3� � �rn\"w Ä ¨�rVw"� � ¨�r m rV}"rV�i] ��� o e � m ] � � mBl r m r g ]#r _ m ["rVtst e _ cV�­d tk] m ]?w­rV\"w�w�] d t c¸e ]?w�r g ] c x m ]z\ g�h w§�w�ts]?wZ� hkmil �i] _ [ g�hkm�e rV\"w g ]zt h rn} h t hkm�e ³Rr��&�½rV\"w d ] g x c3g�� rV\ _ ] d"gic }�ts] � � �¾� [ � ] g�c ["�5]�¢�r �Zd ts]z�r g ] jVh {3]z\ h \ ¹ ^3�nX ÄK� ~vo§]z]ÃrVtk� c Y3r � ]z� � rn["t � � aNc \ jVg ]?��� hkc \�rVt g ] d�c3g9m ¹ ^V�3X Ä5c \ � c3� ] c x mBl ]w h _ ["t mBh ]?� c x�� c x m �½r g ]yw"]z{V]?t cVd"� ]z\ m��¦� � l ] � ]?r g �^VX3X3X � gic }"ts] � h � c x _ c [ g ��]«r � rV�i� h {V]rn\"w d ] g {Vrn� h {V]�]�¢"r �­d tk] c x½{3] g�e }�rVw4� e � m ] � w"]z{V]?t cVd"� ]z\ m;d"g r _ mih _ ]?� mil r m�l r�{3] d ] g � h � m ]?wx cVgI� rV\ e­e ]�r g � �o e � m ] � w"]�{3]zt c3d"� ]?\ m �;x r h t�x c3g r�� h w"]­{nr g�h ] m�e�c x g ]�rV� c \"�zu h \ _ ts["w h \ jµh \�rnw"]� '[�r m ]?t e � d ] _ h �±"]?w g ]� '[ hsg ] � ]?\ m �zu h \"rVw"]� '[�r m ]?t e � d ] _ h ±�]zw � e � m ] � w"]?� hsj \"�zu d�c§c3g¶hk�­d tk] � ]?\ m r mBhsc \"�?u d�c§c3gw c _ [ � ]z\ m r mihsc \1u d�c§c3g�� rV\�r j ] � ]?\ m u5rV\"w d£cPc3g _ l"cVh _ ]z� c x d"g�c3j3g r �­� ] g � � � gic�� ] _ m � mBl r ml rT{V] � rn\ e�d"g�c3j3g r �­� ] g �;��]?] � mBc }�] � [ _ l ts]?���Ft hk� ]zt e²mBc ��[ _?_ ]?]zw1uNrnt mBl�c [ j3l ]�¢ mBg ] � ]zt ejVh x m ]zw � rV\�r j ] � ]?\ m rn\"w©� �'h tkts]zw m ]�r � � c3g�h ]z\ m ]?w d�gic3j3g r �Z� ] g � _ rV\ � r � ];�i[ _ l ]�» cVg�m ���i[ _ �_ ]?����x®["t � ~ ( c �5]z{V] g u mBl ] g ]#r g ]I{3] g�e x®]z� ��[ _?_ ]?���½� mic3gih ]?� �¦� � gic�� ] _ m �5� hkmil�h \�rVw"]� P["r m ]¯� m r \ jcVg��Zh �irV�i� hsj \"]zw d ] g � c \"\"]zt _ rV\ rVts� c }�]���] gihkc ["��t e hs�Zd r hsg ]?w ��º {3] g _ c3�­�Zhkm�m ]zw _ c \ mig r _ mBc3g �rn\"w hs�Zd"gic3d ] g t e­j [ h w"]?wy�i[�} _ c \ mBg r _ mBcVg ��r g ]DrVtk� c � c [ g _ ]?� c x¾w�]z{3]zt c3d�� ]z\ m�gih � � � �

� 8DQ¸E �¾L®>�� =�C�H S¸: O)Q¸E�O)Q�H >fST<�Q !4O Q¸E&%'�'VS¸= � º \"] c x mBl ] �­c � m �i] g�hsc [�� c }"� m r _ ts]z� mBc �i[ g { h {f�rn}"ts]�� e � m ] � �¶rV\"w©\"] m � c3g�� ]z\'{ hkgic \ � ]?\ m � h \f{ c tÂ{3]z� mBl ]�[��i] c x d"g�c3d"g�h ] m r g�e � m rV\"w"r g w"�¶rn\"wd�gic3d"g�h ] m r g9e;d"g�c w�[ _ m �?uf� l"h _ l _ rV\ � r � ] h \ m ] gic3d ] g rV} h t hkm�e � hÂmBl�cVmil ] g � e � m ] � � {3] g�e w h _ ["t m��� l ]?�i]¯w h� _ ["t mih ]z� r gih � h \ j x gic3� d"gic3d�gih ] m r g9e � e � m ] � �5rV\"w h \ m ] g x r _ ]?� _ rV\Z}�]&x®[ g�mBl ] g _ c3�Zd t h �_ r m ]zwÃ} e w"]�{3]?t c3d ] g � � w"]?� hsg ]?� mBc;� r � ] mBl ] hsg5c �&\y\"]�� � e � m ] � �I}"r _ � �½r g w _ c3�Zd r mBh }"ts]&� hkmilmil ] hkg�c tkw"] g � e � m ] � � � � l ]?��] c }�� m r _ ts]z� c x m ]z\ g ]?��["t m¶h \�]?r g t h ] g w"]�± _ h ]?\ _ h ]?�¶}�] h \ jyd ] gid ] m [P�r m ]?w h \ mBc x®[ m [ g ]Ã� e � m ] � � � ¡ [ g9mBl ] gi�Zc3g ]nu�� l"c3g9m �¼� hsjVl'm ]?w _ c3�­� ] g _ h rVt w"]z{V]?t cVd ] g ���i]z] � mic

� �

Page 86: Practical Architectures for Survivable Systems and Networks (Phase

l rT{V]�t hÂmim tk] h \ m ] g ]?� m�h \ � r �'h \ j­mil ] hkg#d"g�c w"[ _ m � h \ m ] gic3d ] g rV}"ts]D� hkmil ts]?���#� h w�]?t e ["��]?w d"g�c w§�[ _ m �Dx gic3�/cnmBl ] g {3]z\"w c3g � � � ] gil r d � �­c � m�hs�Zd£c3g9m rV\ m u d�gic3d"g�h ] m r g9e _ t c �i]?wP��� c [ g _ ]�� e � m ] � �_ rV\"\ cnm }�]F�i["} � ] _ m ]?w mBc�mil ]F�ir � ];� _ g [ mBh \ e«mBl r m � c [ g _ ]���rT{nr h t|rV}�ts]D� e � m ] � � _ rV\ � � l�h � l rn�rntk�Nr e � }£]z]?\ c x d r g�mih _ [�t|r g�hs�Zd�c3g�m rV\ _ ]�x c3g �i] _ [ g�hkm�e u3x c3g � l�h _ lFd ]?] g g ]�{ h ]z�¶u3w�]?� hkj \�rV\"rVt e � h �?u_ c w�];rV\"rVt e � h �?u�rV\"w h \µ� c3� ] _ rV��]?��x cVgi� rVt � ] mBl"c w"� _ rn\ d t|r e rn\«]?\ c3gi�Zc ["� gic tk] h \µw"] m ] _ m �h \ j � e � m ] � ³�rT�&� � � l ]F�Br � ]�r gij [ � ]z\ m r d"d t h ]z� mic ��[ g { h {nrV} h t hÂm�e rV\"w hkm � cVmil ] g �i["} m ]?\�w"]?wg ]� '[ hkg ] � ]?\ m ��rn�&�5]?tkt � ~Ko§]?];o§] _ mBhkc \�� � �TX �¦�

� � !�=zS�> � O)Q¸E&��)Q¸>��4>PJ£S­O Q¸< VSTH 3> � ¿4c ["tsw§�¼}£]¶r _ '[ hsg ] g � c x � e � m ] � ��� hÂmBl _ g�hkmBh _ rVt��i[ g { h {f�rn} h t hkm�e rV\"w��i] _ [ g�hkm�e�g ]� '[ hkg ] � ]?\ m � c x m ]?\ l r�{V]�rn\Z]�{3]z\ �Zc3g ]½w h _ ["t m�m rV� ��mil rV\ mBl ]&� e � m ] �w�]z{3]zt c3d ] g � � q�\ � rn\ e _ rV��]?�zu mBl ] g ]� '[ hsg ] � ]?\ m � mic }£] � ] m r g ]�\ cVm rnw"]� '[�r m ]?t e ["\"w�] g � mBcPc w�ucVg r g ] h \�rVw"]� P["r m ]zt e � d ] _ h ±�]?w ��� {3]z\�� l ]z\ mil ] g ]� P[ hsg ] � ]z\ m �¯r g ]��5]?tkt1]?� m rV}�t h � l ]?w�u�\ c�c »��mil ]��¼� l ]ztkxN� c tk[ mBhkc \"�Dr g ]�t hs� ]zt eªmic ]�¢ h � m u)� l�h _ l \"] _ ]z�i� hÂm r m ]?�;rVw"w hÂmBhsc \�rVt � c x m �½r g ] � � l�h _ l_ rV\ g ]?�i[�t m�h \�x®[ g�mBl ] g w�]z{3]zt c3d�� ]z\ m�d"gic }�ts] � � � ¡ [ g9mBl ] gi�Zc3g ]nu d�gic _ [ g ] � ]?\ m � m ]?\"w mBc x r�{ cVgd�c3d [�t|r g½d�gic w"[ _ m �?u hkgig ]z� d ] _ mBh {V] c x¾� l ] mBl ] gImBl ] e r g ] gic }"["� m?�

��� J'%)>'Q�=zST<"J %)HKJ �4E �&S¸:�> � �)LKJ�>'Q¸<��¾H L H®S¸H®>P=�S¸:�Q¸>P<§S¸=

�<"J %bQ�H = � = � � l ] g ] h �&rn\µ]z\ c3g��­c [��

tsr _ �©c xI[�\"w"] g � m rV\"w h \ jªc \ mil ] d r g�m�c xI� e � m ] � d"g�c _ [ g ] g �?u j3c {3] g \ � ]?\ m�c _ h rVts�zu w�]z{3]zt c3d �] g �zu1� e � m ] � d�gic _ [ g ] g �zu�["�i] g �zu�� e � m ] � rVw �­h \ h � mBg r mBc3g �?u£rV\"w©["��] g � � ¬¯\�x c3g9m ["\�r m ]?t e u _ gihÂmBh _ rVtg ]� '[ hkg ] � ]?\ m �Fx c3g �i[ g { h {nrV} h t hÂm�e rn\"w �i] _ [ gihÂm�e m ]z\"w mBc \"] _ ]?��� hÂm r m ] jVg ]�r m ] g ["\"w"] g � m rV\"w h \ jc \ mil ] d r g�mDc x mil ]?��] h \�w h { h w�[�rVts�zu�rV\"w4rVts� c�d [ m ]�¢ mig ] � ]­� mBg ]?���i]?� c \ _ c3�­d [ m ] g � e � m ] � �zu\�] m � c3gi� �?u�rV\�w d ] c3d ts]¶rVt hs� ] �

� � H���:1@BO�>'Q �¼ERQ �4<�J'3> 3E � O ��S¸H J'� <�J'% 3E���� �)J H�3<�S¸H®E�J ~ ( � aIaI��� � l ]F±�]ztsw c x �i[ d ] g �_ c3�Zd [ mBh \ j4l rV�Ã}£]z]?\��it c �&t e mBg rV\"��x cVgi�Zh \ j hÂm ��]?tkx h \ g ] _ ]z\ mÃe ]�r g � � ¡ c3g w"] _ rVw"]z�?u hkm l rVwg ] � r h \�]?wbr l"hsj3l t e c {3] g � d ] _ h rnt h�� ]?w _ ["t m uN� hkmilbh \ cVg w h \�r m ]µ] �Zd"l rn� h � c \b� d ] _ h rntÂ� d [ gid�c �i]d�gic _ ]?��� c3g �?u mil ]#[��i] c x�rn�i�i] � }"t e _ c w"] h \ mil ] l�c3d ]z� c x d"g�c3j3g r �*c3d�mBhk�­h�� r mihsc \�ufrV\"w mil ]�["��]c x _ c3�Zd"h ts] g �½x c3g ¡ cVg�mBg rV\ªrn\"w cVmil ] g t|rV\ j [�r j ]z� mil r m �N] g ] h \ l ] g ]?\ m t eyh tkt��i[ hÂm ]zw�x c3g&mBl ] h \§�m ]?\"w�]?wFr d"d t h _ r mihsc \�� � � l ] ±�]?tkw�tsr gij ]zt e#hsj \ cVg ]?w g ]zt h rV} h t hkm�e rV\"wDx rV["t m�mBc tk] g rn\ _ ] h \ l r g w��Nr g ] �q m w"] �Zc \"� mBg r m ]?w²{3] g�e t hkm�m ts] h \ m ] g ]z� m¶h \ � r h \"� mig ]?r � _ c \ _ ] d�m � � ��[ _ l rV� � ["t mBhsd�gic _ ]?��� c3gr g _ l"hÂm ] _ m [ g ]?� c3g \"] m � c3g�� ]zw _ c \§± j [ g r mBhkc \"� c x � e � m ] � �?u£rV\"w �­c � m&c x _ c3�Zd [ m ] g � _ h ]?\ _ ] �h \ _ tk["w h \ j­g�c }"["� m rVt jVc3gihÂmBl"� �Ix c3g _ c \ _ [ gig ]z\ _ e u�� e \ _ l"g�c \ h�� r mihsc \1u�w"]�rVw�t c _ � r�{ cVh w�rV\ _ ] � q�\P�w�]?]?w�u hkm¶l rVw rV\ rVt �­c � m�mBcVm rVt�w h �iw�r h \ c xN� l r m � c x m �½r g ] �­hkj3lfm }£]­rV}"tk] mic _ c \ mBg�h }"[ m ]��hkj \ c3g�h \ j�cVd ] g r mih \ j � e � m ] � �?u _ cV�­d"h ts] g½j ]?\�] g r mBc3g �?u � � � � ±�tk]?�zu d�g ] d�gic _ ]?��� c3g �?u mBg rn\"�itsr mBc3g �?urn\"w�w h »�] g ]z\ m r d"d"g�c r _ l ]z� mic;d"g�c3j3g r �­�Zh \ j tsrV\ j ["r j ]?� cVmil ] g�mBl rV\­w"]z{V]?t c3d"h \ j;d r g rVtstk]?t h��?h \ j_ c3�Zd"h tk] g � x cVg tsrV\ j [�r j ]?� \ cVm w"]z� hsj \"]?w�x cVg ��[ _ l ["��]�~ ] �Áj�� u ¡ cVg�mBg rV\ ��� � d�d t h _ r mihsc \ d"g�c3j3g r � ��Zh \ jZl rV����[�»£] g ]zw«x gicV��mBl ] h \�rn} h t hkm�eZmBc ³"]�¢ h }"t e ["�i]D� h w"]zt e r�{nr h t|rV}"tk] g ]z� c [ g _ ]z�?u�rn\"w l rn�rnts� c }�]?]z\ d tsr j ["]zwD� hÂmBlDc {V] g�g ]?t h rV\ _ ] c \�³�rT�5]?w c3g �i["� d ] _ m � hs� ["t|r mihsc \ �Zc w"]?tk� � � �#��� e � m ] � �� hÂmBl � mBg�h \ j ]z\ m �i[ g { h {nrV} h t hkm�eyg ]� '[ hkg ] � ]?\ m � h \ _ g ]?rV� h \ j t e ��]?] �µmBc ] �­d t cTe ��[ d ] g _ c3�Zd [ m ] g �zu��[ _ lyd"gic }"ts] � �Nr g ]�t hs� ]?t e�mic }£]#]�¢�r _ ] g }�r m ]?w � ¡ c3g9m ["\�r m ]?t e u§r;x®]z� ]z» c3g�m � mBc;�­c w"] g \ h�� ] mBl ]±"]?tswµr g ]�±�\�rVtkt e }£] j3h \�\ h \ j�mBc ] � ] g�j ] � h \ _ ts["w h \ j;mil ]D¨ c ¨ ( hkj3l � ] g x c3g�� rV\ _ ] aNc3�Zd [ m �h \ j � c w"] g \ h�� r mBhkc \ � g�c3j3g r � ~ lfm�mBd �¦¥3¥��I�I� �·l"d _ �Zc"�Ál�d _ �Á�Zh t ���+º x _ c \�� h w�] g rn}"ts] d£cnm ]?\ mih rVth \ m ] g ]?� m#h � mil ] ��c3h \ m ¬ a ���¯� (�]��&ts] m�m � � r _ � r g w � rn�i� h {3]zt eÃd r g rVtkts]?t � ] g r � r _ d"gic�� ] _ m uR� l�h _ l

D �����!�135=�Q& � �^_�

�� � ,56 � � � � � 67,)R%Q35&���&`+B/� !�1+B%<��&�+B-�21'H30��+B,/ -�,�>1��'B&R b�Q)*�b���?�Q-�&*��' ML�Q&`&���)*+B,21&�' I 673521' �JIL# �����"35'B&�, 3!����)�&*�"812?�`+B/1%�+B&�+ ML�&�2?-�-435)*Ia,56`�1)*,81'B��-�&b !+ ���A'H35)�=� !J&�%Q35'B�9&*+B-[21'H30�*+B,/1&F8LI <�# $V#:�����WML��/1&*,/ � � � � � #

� �

Page 87: Practical Architectures for Survivable Systems and Networks (Phase

r _ l"h ]�{3]?�;�i[ d ] g _ c3�Zd [ m ] g _ r d rV} h t hÂmBh ]?��w"]z� d"hÂm ] mBl ] d"g ]z�i]?\ _ ] c x l ["\�w g ]zw"� c x mil"c ["�irV\"w"� c xl r g w��Nr g ]5w"]�x®] _ m � ¹ �¸^�� Äv� q�\Fr g r mBl ] g \ c {V]?tPr d"d�gic r _ l u d"g�c _ ]?�i� c3g x®["\ _ mihsc \"rVt hÂm�e#h �)w�] m ] gi�Zh \"]zwr�x m ] g�hs�Zd ts] � ]z\ m r mBhkc \ g r mBl ] g1mBl rn\D� d ] _ h ±�]?wD}£]�x c3g ] l rV\"w�u mil [�� r _?_ cV�­�Zc w"r mBh \ j � l r m � c ["tkwcnmBl ] g � h ��]�}£] _ c \"� h w"] g ]?w mBc }�] d ] gi� rV\"]z\ m x rn["t m#�­c w"]?� ��hkm w c ]?��� l r m¶hkm w c ]?�Z~ rVt mil"c [ jVlhÂm�h ��\ cVm _ tk]�r g�l"c � hkm�l rn\"w"ts]z� mBg rn\"� h ]?\ m x rV["t m � ��� � m r _ c3�Zd ts] m ]zt e w h »£] g ]?\ m¶d£cVh \ m¶h \ mBl ]r g _ l"hÂm ] _ m [ g rVt¾� d ] _ mig [ � u � rV��� h {3] _ cV�­d [ m r mihsc \�rnt g ]?� c [ g _ ]?� _ rV\²}�]�r _ '[ hkg ]zw c {V] g�mBl ]�q�\P�m ] g \"] m uPx c3g ]�¢�r �Zd tk]VuP["� h \ j o§[�\ � h _ gic � e � m ] � � � �&Y h \ h uf� l"h _ l [��i]?�½Y3r�{Vr mBc ]z\�rV}"tk]#r g } hÂmBg r g�e�Zc w"]?� c x�w h � mBg�h }"[ m ]?w � [�t mBhkd"gic _ ]z�i� h \ j r _ g�c �i� mil ]�q�\ m ] g \"] m��5aNc \"� h w"] gih \ j;mBl ] d£c �5] gIc x mBl ]�Zc } h ts]�� _ c w"] d r g rnw hsj3� ~voP] _ mihsc \«  � � � u mBl r m r d"d"gic r _ l�h �It hk� ]?t e�mic � h \ c [ m¯h \ � rV\ e _ rn�i]?� �

�#t mBl"c [ j3l ]?\ mBhkg ]y} c§c3� � _ rn\�}�]µrV\"w l r�{3]µ}£]z]?\�� g�hkm�m ]?\�rV} c [ m�mil ]?��]«w"]�± _ h ]?\ _ h ]?�ZrV\�w mBl ]g ]z�i["t mBh \ j©gih � � ��~ ] �·j"� u ¹ �n�"u ^3�VX Ä � u mil ]y] �Zd"l rV� h � l ] g ] h � c \ c {3] g _ c3�­h \ j©mBl ]Ãw�]z± _ h ]?\ _ h ]z� � rn�rVw"w g ]?���i]zw h \ mil ]¶\"]�¢ m _ l r d�m ] g?�

� �

Page 88: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� � � � � � � � � � � � � � � ��� � � � � � �

� ��� � � � � � � � �

� � � � � � � � � � � ����� � � ����� � � � � � � � � � � � � � � �� ��� �& � �F� � � � � � � ��� � ��� � � ������� ����� �& ��� ���ts}�] g9m&��h \"� m ] h \

��h {3]z\ mBl ]Zw"]z± _ h ]z\ _ h ]?� h w�]?\ mBh ±�]?w h \ aNl r d§m ] g �"u��5]­\"]�¢ m _ c \"� h w"] g � l r m;�ZhsjVl'm }£]�w c \�] micc {3] g _ cV� ] mil ] �µ� � r gihkc ["�;r d"d"g�c r _ l ]z� mBc �½r g w d"g ]z{3]z\ mBhsc \1u w"] m ] _ mihsc \�u g ]�r _ mBhkc \1u�rV\�w hkm ] g r mihsc \r g ];�i[ �­� r gih�� ]zw h \ � rV}"ts];� � �;x c3g ]�r _ l«c x mBl ] mBl"g ]?] d"gihk� r g9e r m�mBgih }"[ m ]?� c x��i[ g { h {nrV} h t hkm�e \ cVm ]zwh \ ¡ hkj [ g ]�W � �­rn\"w²w h � _ ["���i]?w�x®[ g�mil ] g¶h \ mBl"h �¶rV\"w��i["}"��]� '["]z\ m _ l r d�m ] g � � o d ] _ h ± _ r g _ l�hkm ] _ m [ g rVtg ] _ c3�Z� ]?\"w�r mBhsc \"�&r g ] _ c \"� h w"] g ]?w h \ aNl r d�m ] g  ;x c3g � e � m ] � �#rV\�w�\"] m � cVgi� ��� hÂmBl � mBg�h \ j ]?\ m �i[ g �{ h {nrV} h t hÂm�e�g ]� '[ hsg ] � ]?\ m � � ¬�t mBhk� r m ]?t e u mBl ]�["��] c x g�c }"["� m r g _ l"hkm ] _ m [ g ]?� h �¾rn}"� c tk[ m ]zt e x®["\�w�r � ]?\ m rVtmBc�mil ] g ] _ c3�Z� ]z\"w�r mihsc \"� c x mil"h � g ] d�c3g�m?�

� -/-/%?&$!�;?H ��#KJ6!87 03J3039�" � #L;�A�%�0G9�" �j#%�( &,%?+1!�=�;#p �S� � � R � � � R � ��������W�<��V�_ � ����Vf�����S� � � �����,�e�W���SV�_ � ���4VX�S����� � � ��������W�<��V�_ � ����Vf�����S� �

� �4O8� R O�� R V:` � rW��c� ��R � ������<� � � R ] uL�,�<�S��V��<���V � �e`�����S���PVf����S��Vf� � � R ] ��V:V:���S�tVf� R �S�������]Y3����� �P�S�����:��� R V:� �<�8�S_���� ��� ��� � � R ]K�������:��� R Vf�

rj�f���4VX� � � R � �4O8� R O�� R V:` � �oR �S�:Q� � �e`gV�_��4V b ��] p ����YG����F� R Vf�\��� R � ����� ��R Q�����S���PO8�:����Vf� � � R � R ��c����`���� � ��������O8�:����Vf� � � R

� �4��VX� � � R �����Sxh���SO,������V b xt�<��O^] uL��V:��� � �e` ���S�����:� � ��R Q � �4Vf� R ��Q����S�<� � � R�S��V:� � �:�S` ���4Vf� R ��Q�������� � � R ]K��������S� R Vf�

� �����S�<� � � R �,�<�����N�����c� � ��� � � ���������������` � �4O8��� � Q R ]���$a>� ��R � ������V�_���� �S�S�O8�:� ���

�/�<����� �8¦Å�� rW�:YG� R � ��� � k~�4���������4�

� �

Page 89: Practical Architectures for Survivable Systems and Networks (Phase

��)+( � �5,������������ ��� ,�-������P��� ,�-¶9, � � ,�- � � � ��9���)(*�),½���

� ] gil r d � mil ] �Zc � mDhk�­d�c3g�m rV\ m � m ] d4mic �Nr g w r m�m r h \ h \ j � e � m ] � rV\�w4\"] m � c3g�� r g _ l"hÂm ] _ m [ g ]?� mBl r mr g ] _ r d rV}"ts] c x � ]z] mBh \ j rVw§{Vrn\ _ ]zw ��[ g { h {Vrn} h t hkm�e g ]� P[ hsg ] � ]z\ m � h � mBc l r�{V] r4�5]?tktÂ�¼w"]z±�\�]?w �i] mc x¯w"] m r h ts]?w g ]� '[ hkg ] � ]?\ m � � ( c �5]z{V] g u5x c3gFmil"c �i] g ]� '[ hkg ] � ]?\ m � mic }£]Ã��]?\"� h }"t e � r m _ l ]?w mBc©mBl ]g ]?rVt h � mih _ \"]?]zw"�?u hkm;h � hk�­d�c3g�m rV\ m�mil r m�mBl ] g ]Ã}�]yr��N]ztst ��w"]�±�\"]?w rV\�w �N]ztstÂ�¼["\"w"] g � mBcPc w �Zc w"]?t c xmBl ] �Zh ��� hkc \ mBl r m r²� d ] _ h ± _ � e � m ] � h � h \ m ]?\"w�]?w mBc x®["tk±"tst � q�\ mBl ]µrV}"��]?\ _ ] c x#��[ _ l r �Zc w"]ztvuhkmZh �­w h� _ ["t m­mic rV���i]?��� mBl ]ªrVw"]� '[�r _ e�c x¶r j3h {V]?\ r g _ l"hÂm ] _ m [ g ]Vu mil ]«w"] d ]z\"w"]z\ _ ] c \�]�¢ m ] g \�rnth \§x g rV� mBg [ _ m [ g ]?�#rV\"wª��["}"� mBg [ _ m [ g ]?�zu�rV\"w mBl ] _ c \"��]� '["]z\ _ ]z� c x � e � m ] �Zh _ } g ]?r � w c �&\"� c3g r mim r _ � �c \ mBl ]D� e � m ] ���� � c m�e§d ]?� c x �Zc w"]?tk�¯� c ["tkw©}£]F[��i]zx®[�t � j ]z\"] g�h _ �Zc w"]?t�x g r � ]z� c3g�� � mBl r m _ rV\©}�] m r h t cVg ]?w

mBc � d ] _ h ± _ \�]?]?w��?u£rV\"wy� d ] _ h ± _ �­c w"]zts�Ir d�d t h _ rV}"tk] mBc�d r g�mBh _ ["tsr g � e � m ] � � �

��) &% �P��� ( � ,�- .0�1�324�5��6¯9, � � ������¼�"�����"�������

� � c x®["\"w�r � ]z\ m rVtst e w h »�] g ]z\ m r g _ l"hkm ] _ m [ g rnt5r d"d"gic r _ l ]?�;�i]?] � d£c ��� h }"ts]�� ] hÂmBl ] g�h \ _ g ]�rV��] mBl ]�i] _ [ g�hkm�e u g ]zt h rn} h t hkm�e u1rV\"w ��[ g { h {nrV} h t hÂm�eªc x mBl ] �­c � m _ gihÂmBh _ rVt _ cV�­d�c \"]z\ m �?u c3g ]zts��]�w"]�{3]?t c3d � e ��m ] � rV\"w²\"] m � cVgi� r g _ l�hkm ] _ m [ g ]z� mil r m r g ]��i[ g { h {nrV}"ts]�w�]?� d�hkm ] mil ] d"g ]z�i]?\ _ ] c x h \ l ] g ]?\ m t e �5]�r �_ cV�­d�c \"]z\ m � � q�\ d"g r _ mBh _ ]nu"r _ c3� } h \�r mBhsc \ c x)} cVmBl r d�d"gic r _ l ]?� h �Nw"]?� hsg rn}"ts]nu�x c3g ��]z{3] g rVt g ]�rV� c \"�z�

� � \"wP��["��] g¯d ] g � c \�rVt _ cV�­d [ m ] g �?uR\"] m � c3g�� _ c3�Zd [ m ] g �zu l rV\"w§� l ]?tkwÃ� hsg ]zts]z�i�¯["\ hkm �?uRrV\�w�w"[ � }m ] g��­h \�rVts�¾r g ]It hs� ]?t e�mBc }�]It c �N]z� m � _ cV�­�Zc \§�¼w"]?\ cV�­h \�r mBcVg _ cV�­d�c \"]z\ m � � hkmilZg ]?� d ] _ m�mBc _ g�hkm �h _ rVt g ]� P[ hsg ] � ]z\ m �?u�x c3g½mil ]�x c3g ]z�i]z]�rV}"tk]�x®[ m [ g ] �

� q�\ m ]?tst hsj ]z\ m � c3gi� � m r mihsc \"� r g ]5\"]z{V] g t hk� ]zt e�mBc ]?\�x c3g _ ] � ["t mih ts]�{3]ztP��] _ [ gihÂm�e3�¾¿�l ]z\"]z{V] g � �)o h �]z�i��]?\ mBh rVtvu'r g _ l"hkm ] _ m [ g rVt�rVt m ] g \�r mih {3]z� � ["� m }£]I]�¢ d t c3hÂm ]?w mil r m w c \ cVm g ]� '[ hkg ] � �)o�]?\"w§�¼["�i] gd t|r m x c3gi� � �

� o e � m ] � ��rV\"wZ\"] m � c3g�� � m ]?\"w mBc }£] l ] m ] gic3j ]?\"] c ["�?u§rV\"w � ["� m r _?_ c3�­�Zc w�r m ]Nw"]z± _ h ]z\ m _ c3� �d�c \"]z\ m �&]z{V]?\�� l ]?\ mil ] eyg ] d"g ]?��]?\ m#d�cVm ]?\ mBh rVt��5]�r � t h \ � � �

� ( hsj3l ��� d ]?]zwµ� hkg ]zts]?��� _ c3�Zd [ m ] g � _ c3�Z� ["\ h _ r mihsc \�� l"c tkwµ]z\ c3g��­c [�� d�cVm ]z\ mBh rnt1x c3gImBl ]�x®[ m [ g ] �� l ] e rVts� c�j3g ]?r m t eÃh \ _ g ]?rV�i] mBl ]D\"]z]?w"�#x cVg � e � m ] �­h _ ��] _ [ gihÂm�e u _ g�ePd�mic3j3g r d"lfe u d"g ]�{3]z\ mihsc \ c xw�]?\ h rVts� c x¾��] g { h _ ]Vu�rV\�w c {3] g rVtkt1�i[ g { h {nrV} h t hÂm�e3�

q�\"w"]z]?w1u _ c3�Zd£c \"]?\ m ��[ g { h {Vrn} h t hkm�e _ rV\ }�]?\"]�± mFjVg ]�r m t e x g�c3� _ cV�­d�c \"]z\ m w h {3] g � hÂm�e u d r g�mBh _ [§�t|r g t e¶h \ mBl ] _ c \ m ]�¢ m c x�r g _ l�hkm ] _ m [ g ]z� mBl r m r g ]½w�]?� hkj \"]zwFx c3g gic }"["� m \"]?��� � q�\���[ _ l rV\�r g _ l�hkm ] _ m [ g ]nuhkm }�] _ c3� ]z�¾]z�i�i]z\ mBh rnt mic#h w�]?\ mBh x e�mBl ] �­c � m _ gihÂmBh _ rVt _ cV�­d�c \"]z\ m �?uVrV\"w mic _ c \ _ ]z\ mig r m ]N��[ _ h ]z\ m r g �_ l"hÂm ] _ m [ g rVtR� mig ]?\ jVmBl � h \ mBl"c ��] _ c3�Zd£c \�]?\ m � � � l ]#}�rn� h _¯_ l rVtkts]z\ j ] h � mBc _ c \�� h w�] g rn}"t e�g ]?w"[ _ ] mBl ]]�¢ m ]?\ m mBc � l"h _ l rntst���["}"� e � m ] � � � ["� m }£]I]�¢ m ]?\�� h {V]?t eFmBg ["� m � c3g�milfe3� q�w"]?\ mih x ePh \ j�mil ] _ g�hkmih _ rnt _ c3� �d�c \"]?\ m �¶rV\"w �Zh \ hk�­h��?h \ jFmBl ]Fw�] d ]?\"w"]z\ _ ] c \©[�\ mig ["� m � cVg�mBlfe _ c3�Zd£c \�]?\ m ��r g ]F} cVmBl ]�¢ mBg ] � ]zt ew h� _ ["t m uIrV\"wbr g ] d [ g ��["]?w h \ mBl�h � g ] d�c3g�m?� ��� \ cVm ]?w h \�o§] _ mBhkc \ � � �3u l rT{ h \ j r �5]?tktÂ��w�]z±�\"]zw�Zh �i� hsc \ �Zc w"]?t�rn\"w�w�] m r h ts]zw g ]� P[ hsg ] � ]z\ m � h �¯rF{ hkm rnt d"g ] _ [ g � c3gz�

o e � m ] � r g _ l�hkm ] _ m [ g ]z� � ["� m rVw"w g ]?��� mBl ]�\"] _ ]?���Br g9e �i[ g { h {nrV} h t hkm�e � g ]?tk]z{nrV\ m¯g ]� P[ hsg ] � ]z\ m �?u h \§�_ tk["w h \ j g ]zt h rn} h t hkm�e u5x rV["t m�mBc tk] g rn\ _ ]nu#rV\�w ��] _ [ gihkm�e � hsg�g ]?� d ] _ mih {3] c xD� l"h _ l _ c3�Zd£c \�]?\ m �µr g ]r _ m [�rVtkt e©mig ["� m � c3g9mBlfe � hÂmBl g ]?� d ] _ m�mBc � l"h _ l g ]� '[ hsg ] � ]?\ m � � q�\ rVw"w hÂmBhkc \1u mBl ]z�i]yr g _ l"hkm ] _ m [ g ]z�

� Å

Page 90: Practical Architectures for Survivable Systems and Networks (Phase

� ["� m }£]½³"]�¢ h }"tk]I]?\ c [ j3l�mBc �i[ d"d£cVg�m g ]?rVtÂ� mBhk� ]5r d"d t h _ r mBhkc \"� rn\"w��i[ d ] g _ c3�Zd [ mih \ j¶g ]� '[ hsg ] � ]?\ m �zug r mBl ] g mBl rV\�\"] _ ]z�i� hÂm r mih \ j � d ] _ h rntÂ� d [ gid�c �i]Nw"]?� hsj \"� � � r g�hsc ["� r g _ l"hÂm ] _ m [ g rVtRrVt m ] g \�r mih {V]?��r g ] _ c \P�� h w"] g ]?w h \ aNl r d§m ] g   � �#\ rVt m ] g \"r mBh {3] mBl r m r d"d�gic r _ l ]?� � [�t mBh ts]�{3]?tR��[ g { h {nrV} h t hÂm�e ~voP] _ mihsc \«� � ^ � � ��Zhsj3lfm tk]�rVw mic r �i]?\�� h }�ts]�� e � m ] � � mBg [ _ m [ g ] mBl r m�h � c x h \ m ] g ]?� m ]z{3]z\ h \©\ c \§� � �)oª� e � m ] � ��rn\"w\"] m � c3g�� � � ( c �N]�{3] g u � �)o � l�c ["tsw }£] m r � ]?\ \ cVm rn�FrV\4r mim ] �Zd�m ]zw4["\ h {3] g �Brnt d"g�c3d ] g�m�e c x � ] g �\"]zts�½rn\"w mBg ["� m ]?w _ cV�­d [ mBh \ j }�rV��]?�D~ rV�5�NrV�Ir m�m ] �­d�m ]?w � hÂmBl � �)o � u§}�[ mIg r mBl ] g rV�Ir d£cVm ]?\ mBh rVtst e["��]zx®["t)r g _ l"hkm ] _ m [ g rnt1w gih { h \ j x c3g _ ] h \ mil ] _ c \ m ]�¢ m#c x mBl ]D\ cVmBhkc \ c x j ]?\"] g rVt h�� ]zwyw"] d ]?\"w�]?\ _ ] �� ] gil r d � mil ] �­c � m x®["\"w�r � ]?\ m rVt)r g _ l"hÂm ] _ m [ g rVt _ c \ _ ] d�m�h \f{ c tÂ{3]?� mBl ] h � c tsr mBhkc \ c x d£cVm ]?\ mBh rVtst e

}�rVw r _ mih { hkmih ]?��x g�c3� � l r m ]�{3] g x®["\ _ mBhsc \�rVt hÂm�e�� ["� m }�] mig ["� m � c3g9mBlfe3� � l"h � h � _ c \"� h w"] g ]?w h \ aNl r d �m ] g   �

��)�� &% �P��� ( ������������ ���� ��� ���������������� � � "! � "� �#���$�

%'&)()*,+.-0/21$354 /$-6*,&87�*,9�:;*<&>='+.7�*,+./$?@/$&>*BA�-�CEDGF$CE-�*E-'()-0HI7"HI&8:KJ�&L7�-0MN&>*,9$+./$?O*E-@PQ&LR$&)7E+IC�&8R2A�+5*,92C�&87EFQ&8(>**,-�/$&>*BA�-0C�DO7�S$C�JT+5J�:6P$+IH.+.*BU03WV�-KA�&>J0&8C)X0*,9$&)CE&�+I7Y:�/O:�MZ:6[8+I/�?\:6MN-0S�/]*#-�^�&8/$&)CE?�UO:�/�R_&)`a-0Cb*Y?�-0+I/$?�+I/c*E-F$C�-�*,-T(8-0HdR�&)J0&)HI-0F�MN&)/]*83Ze�-0CfP�:6(gDT?�CE-0S$/�Rh-0/ji�k<l�m6n�lo:�/$RjCE&8HI:6*,&)RpF$CE-�*E-'()-0HI7)XW7E&8&q*,9�&NMN:�7E7�+.J�&(8-�HIHI&)()*E+I-0/r-�^OnB/c*,&)CE/$&>*sR�C,:6^t*uF$C�-0Fa-�7,:�H.7v:�/$Rw7ES$P�7E&8x]S$&)/c*,H.Uzy�&8x]S$&)7�*,7u^{-0Cuk�-0MGMN&)/c*,7j|}y�e#k�7g~�XA�9$+.(g9s()-0HIH.&8()*E+.J�&8H.UNCE&)F$CE&)7E&)/]* :�?0-0HIR�MN+./$& -�^Y+I/�^{-�CEMN:6*,+.-0/Z-0/u&8MG&8C�?0+I/�?�nB/]*E&8C�/$&)*\F$CE-6*,-T(8-0H.783nB/h*E9$&2+I/c*E&8CE&)7�*�-6^�R$C,:�MN:6*E+I(�:6HIH.U�+I/$()CE&8:�7E+./$?�-KJ0&)C,:�H.H�/$&>*BA�-�CEDhC�-0P$S$7b*,/$&)7E7)X�*BA"-�/$&>A�nB/c*,&)CE/$&>*

� /$?0+./$&8&)CE+I/�?GiY:�7�Dve�-0CE()&Z|{n � i�ed~<R$C,:6^t*�nB/c*E&8CE/�&)*\F$CE-�*E-'()-0HI7�:6CE&�-�^YF�:�Cb*,+I()S$H�:6C<+I/c*,&)CE&)7�*�9$&8C�&��

� %T+IMGF$HI&pk�-�/]*ECE-0H�i#C,:6/$7EMG+I7�7E+I-�/zldC�-�*,-T(8-0H�|�%$k�i�l�~>X�FQ-�*,&)/c*,+�:6HIH.U�:�CE&)F$H�:�()&8MG&8/c*�^{-0C�i�k<l��9c*�*,F���m0m;A�A�Af3�+I&>*E^�3�-0CE?]m;+I/c*,&)CE/$&>*��BR�C,:6^t*E7gm6R$CE:6^t*���+I&>*E^��B7�+I?�*EC,:�/T�B7E(>*,F'�B�c�'3�*�=T*

�j� +.7�*ECE+IP�S�*,&)R � :6*g:�ldCE-6*,-T(8-0H�| ��� l"~�X$+I/v()-0/�^{-0C�MZ:6/$(8&�A�+.*E9uy\e#k��6�c�����9c*�*,F���m0m;A�A�Af3�+I&>*E^�3�-0CE?]m;+I/c*,&)CE/$&>*��BR�C,:6^t*E7gm6R$CE:6^t*��}='+I&>��7�*E&)A�:�C�*b�B7E+.?�*,CE:�/'��R$R$F'�B�0��3�*�=T*� MG-0/$?@*E9$&f&>='+I7b*,+./$?Gy\e#k�78X�7�&)J�&8C,:6HYC�&8(8&)/c*L-0/�&87�:�CE&�A"-0C�*E9s/�-�*,+./$?$�

� y�e#ko�61c��40��9c*E*EF���m�m;A�A�Af3�+.&)*�^�3�-0C�?]m6Cb^{(Km6Cb^{(K�61c�'403�*b=T*�X�R$CE:6^t*�7�&8(8S�CE+.*BU�:�CE(g9�+.*,&)()*ES$CE&@^{-0C�*,9$&�nB/T�*E&8C�/$&)*\ldCE-�*E-'()-0H�X'PcUs%a3���&8/c*L:�/$Ruy�3 � *ED]+I/$7�-0/�X¡ \-KJ�&8M@PQ&8Cf4K¢0¢�£i�9�+I7�F$C�-¤JT+.R$&87�7E&)(8S$C�+.*BUv7�&8C�JT+.(8&87�^{-0C<*E9$&fn�l"¥¦H�:�U0&)C�+./�n�l§J0&)CE7E+.-0/$7�1G:�/$Rs��3

� y�e#k¨�61c��£��<9c*E*EF���m�m;A�A�Af3�+.&)*�^�3�-0C�?]m6Cb^{(Km6Cb^{(K�61c��£�3�*b=T*�X¡*,9$&OnB/]*E&8C�/$&)*�%T&8(8S�CE+.*BU � 7E7E-T(8+I:6*,+.-0/�:6/$R��&>Uu©�:�/�:6?0&8MG&8/c*\ldCE-�*E-'()-0H�|ªnb% � ��©�l�~>3

� y�e#k��61c�0¢'�#9c*�*,F���m0m;A�A�Af3�+I&>*E^�3�-0CE?]m;C�^{(Km;C�^{(K�;1c�0¢�3�*�=T*�X;*,9$&"nB/c*,&8C�/$&)*���&>U � ='(g9�:�/�?0&�|ªn�� � ~>X6F$CE-6�JT+.R$&87�:�S�*E9$&8/c*E+I(�:;*,&8RuD�&>UT+I/$?GMZ:;*,&8C�+�:�HQ^{-0C�S$7�&fA�+5*,9unb% � ��©�l#3

� y�e#ko�61$4040��9c*E*EF���m�m;A�A�Af3�+.&)*�^�3�-0C�?]m6Cb^{(Km6Cb^{(K�61$4�403�*b=T*�X«*E9$&�n�l�%T&8(8S�CE+.*BU � -'()S$MG&8/c*fy�-c:�R$MN:�F�X+.7�9$&8H.F�^{S$H�+./�CE&8HI:6*,+./$?@*,9�&fJ6:�C�+I-0S�7<R$-T(8S$MG&8/c*,7�*,-q-0/�&O:6/$-�*,9�&8C83

� y�e#k��61$4¤�T�#9c*�*,F���m0m;A�A�Af3�+I&>*E^�3�-0CE?]m;C�^{(Km;C�^{(K�;1$4¤�'3�*�=T*�X6*,9$&�¥ � �f¬ � � ��&)U � &)*,&)CEMG+I/�:;*,+I-�/_ldCE-;�*E-'()-0H�X'+I7�P�:67E&8Ru-0/�*,9$& � + &���V�&8HIH.MZ:6/ZD�&>U�&>='(g9�:�/�?0&@:�H.?0-0C�+.*,9�Ms3

��­

Page 91: Practical Architectures for Survivable Systems and Networks (Phase

V\-KA"&)J�&8C8X]:6HIH0*,9�&<y�eYk�7�:�/$ROnB/]*E&8C�/$&)*dR�C,:6^t*E7�:�C�&�/$&)(8&)7E7,:6CE+IH5U�*,9$&"S$H.*E+IMN:6*,&�:6/$7�A"&8C�7 +I/�*,9$&)MN7�&8H.J�&87)3©sS$(g9sMN-�CE&�CE&)MZ:6+I/$7�*E-NPQ&�R$-0/�&�3¥L^�F�:�C�*E+I()S$H�:�CO+IMGFa-�C�*g:6/$(8&2+.7_*,9�&v/$&8&)R ^{-0C�C�-0P$S$7b*qF$S$P$H.+I(��BD�&>U+./�^{C,:�7b*,C�S$()*ES$CE&)7�|ªl��fnB7,~O*,9�:;*

(8-�MNF�:;*,+IP�H.U�F$CE-KJT+IR�&�F�S$P$HI+.(>��D�&)U@(8&8Cb*,+���(�:6*E&87�:�/$R�J6:�H.+IR�:6*E+I-0/O-�^Q*,9$&�?0&)/TS�+I/$&)/$&87�7"-�^Q*,9�&�()&8Cb*,+��$(�:6*E&:�S�*E9$-0C�+.*,+.&87�:�/$R J0&8C�+���(8:6*,+.-0/:6S�*,9$-�CE+.*E+I&)78XYA�+5*,9 7ES��G(8+.&8/c*,H5Uj?0-'-TRhFQ&8Cb^{-0CEMN:�/$()&�X#*,-�MN:�D�&N(8CbU'FT�*,-�?0C,:�F�9$+I(8:�HIH5UpF$CE-�*E&8(>*,&8R +./]*E&8C�-0Fa&)C,:�P�+IHI+5*BU�F$CE:�()*E+I(�:6H�3j©�:�/cUh(8-0MGMN&)CE()+�:�H�R$+.7�*,C�+IP$S'*,&8R l���nB7q:�C�&&8MG&8C�?0+I/�?$X�:�/�Rp:�CE&@&�='Fa&)()*,&)Rj*E-2A�+I/�-0S'*�-KJ0&8Cf:Z^{&>A¦9$+I?09�H.UuS$/$+���&8Rjl���nB783OV\-KA�&>J0&)C8XW(8-0MGF�:6*E+5�P$+.HI+.*BUs:�/�Rj+./c*,&8C�-0FQ&8C,:6P$+IH.+.*BUu:�C�&@7�*E+IHIHYP�:�R$H5U�HI:�?0?0+./$?$3�k�&)C�*,+���(�:;*,&q:�S�*E9$-0C�+.*,+.&87�:6CE&@PcU�*E9$&8MG7E&)H.J0&)7+I/�9$&8C�&8/c*,H5U HI+IMG+.*E&8Rz|{^{-�CG&�=�:�MNF�HI&�X�P]U +.7E7ES�&872-�^\*,C�S$7�*BA"-0C�*E9$+I/�&87E7,~>3���:�HI+.R�:6*,+.-0/ :�S�*E9$-0C�+.*,+.&87G:�C�&/$&)(8&87�7,:�CbU03@nB/�&)7E7�&8/$()&�XY:2(8&8Cb*,+���(�:6*E&�:�S�*E9$-0C�+.*BUs(�:�/�PQ&�+I7�7ES$&)R�-�`Q��HI+./$&@:�7L/$&8&)R$&8R�3 � J6:�HI+.R�:6*E+I-0/:�S�*E9$-0C�+.*BU�+I7�+I/cJ�-0D�&)R�-0/'�BH.+I/$&fFQ&8C�*,CE:�/$7,:6()*,+.-0/�Xa:�/$Rs(�:�/�F�CE-KJT+IR$&O7�*,C�-0/$?0&)C\C�&)J�-'(8:6*,+.-0/�Xa:�7L+./s*,9�&��:�H.+I(8&)C�*�:6F$F$CE-0:�(g9s-6^�()&8C�*E+���(8:6*,&fC�&)J0-T(�:;*,+I-�/�*ECE&)&87_|ª7E&)&f9]*�*,F���m0m;A�A�Af3�J6:�HI+.(8&)C�*�3�(8-�M2~�3� ='+I7�*E+I/$?L(8C�UTF�*E-0?0CE:�F$9$+.(�:�HI?0-�CE+.*E9$MG7<|{&87EFQ&8()+�:�H.H.Uf*,9�& � � %�:�HI?0-�CE+.*E9$MG7g~W:�F$FQ&�:�C�*E-�Pa&�:6R$&8x]S�:6*E&

^{-0C�*,9$&�^{-0CE&)7E&)&�:�P$H.&�^{S'*,S$C�&_/$&)&8R$7)3LV�-¤A"&)J�&8C)X�A�&OS$CE?0&)/c*,H.Uu/$&)&8R�PQ&)*�*,&)CL(8CbUTF�*,-0?�C,:�F$9�+I(�F$CE-�*E-'()-0HI7:�/$R�?0CE&8:6*,&)CLR$&)Fa&)/$R�:�P$+.HI+5*BU�+I/�*E9$&8+.C\+.MNF$H.&8MG&8/c*g:;*,+I-�/$783�e�HI:KA�7�9�:�J0&�PQ&8&)/�R$+I7�(8-KJ0&)CE&)R�+I/�J6:�C�+I-0S$7FQ-0F$S$HI:�C�F$CE-6*,-T(8-0H.7�|t^{-0C�&>=�:�MGF$H.&�X< �&8&)R$9�:�M��b%'(g9�CE-T&8R$&)Cg~>3r%'&8&�:jC�&8(8&)/c*2CE&)Fa-�C�*GPcU � P�:�R�+\:6/$R��-0CER$-�/�����:67"F�:6C�*<-6^W:_7E&)CE+.&87�-6^�F�:�FQ&8C�7�-0/Z^{-�CEMN:�HI+.[8+I/�?�(8C�UTF�*E-0?0CE:�F$9$+.(\F$C�-�*,-T(8-�HI7L|{*,9�&)UN+I/$()HIS$R$&(8-�F$+I-0S�7�CE&)^{&)CE&)/$(8&)7\*,-q&8:�CEH.+I&8C"A�-0C�D'~>XQ:�HI-�/$?@A�+.*E9�^{S�C�*,9�&8C�R$+I7�(8S$7�7E+.-0/s+./s%'&8(>*,+I-�/ �T3�¢�3k�-0MGFa-�7,:�P$+.HI+5*BU�-�^_(8-0MGFQ-0/$&8/c*E7s7�S$(g9�:�7�F$C�-�*,-T(8-0Hf+.MNF$H.&8MG&8/c*g:;*,+I-�/$7Z+.7u()-0/$7�+IR$&)CE&8R�+I/�%'&8(��

*,+.-0/��'3�£�3 V\-KA"&)J�&8C8X�()-0MGFa-07E:�P$+.HI+.*BU PcU +.*E7E&)H.^�+I7v/$-6*�&8/$-0S�?09�3 ��/$-KA�+I/$?�*E9�:6*�JTS$HI/$&)C,:�P�+IHI+5*,+.&87:�PQ-0S$/$R«X¡:GF�:6C�*,+.(8S$HI:�C<()-0/$(8&)CE/s+I7<*,9$:6*�P]U�()-0/$()&8/c*,CE:6*,+./$?G*ECES$7b*BA�-�C�*,9�+I/$&)7E7 :6CE-0S$/�Rs-0/�&f^{S�/$()*E+I-0/'�:�H.+.*BUs7ES$(g9h:�7�:�F�S$P$HI+.(>��D�&)U�+I/�^{CE:�7�*ECES$(>*,S$C�&GMN:�D6&87�*,9�:;*�^{S$/$()*E+I-0/$:�HI+5*BU�:�/ :6*�*,C,:6()*,+5J0&�7�S$P���&8(>*O^{-�C:6*�*g:�(gD¡3 � J0&)/w+5^�*,9$&�MN&)(g9�:�/$+.7EMG7N*,9�&8MG7E&8H5J0&)7v9�:�J0&p:�R$&)x]S�:6*,&�+./c*,&8?�CE+.*BU§:�/�R�/$-0/$7�Fa-T-�^ª:�P�+IHI+5*BU|{A�9�+I(g9u+I7�S$/$H.+ID6&8H.U�~�X�*,9$&>UvPQ&8(8-�MN&f&�:67�Uv*g:6CE?0&>*,7<^{-0C�R$&)/$+�:6H5�B-6^��B7E&)C�JT+I()&�:6*�*g:�(gD]783y�-¤JT+./$?p&8/$R'��S$7E&)CN*E&8CEMG+I/$:�HI7@A�+5*,9 A�+ICE&)HI&)7E7G(8-0MGM@S$/$+.(�:6*E+I-0/�7@CE&)F$CE&)7E&8/c*v9]S$?�&s(g9�:6HIHI&)/$?0&)7q^{-�C

/$&>*BA�-0C�D]+I/$?$3"%T*ECE-0/�?G/�-0/$(8-�MNF$C�-0MG+I7E+.P$HI&\&8/$RT��*,-;�B&8/�Ru()C�UTF�*E-0?0C,:6F$9cU�+I7�&87�7E&)/]*E+�:�H��$HI+./$DG&8/$()C�UTF�*,+.-0/MN:KUu:6HI7E-NPa&O+IMGFa-�C�*g:6/]*8X¡F�:�C�*E+I()S$H�:�C�H.UZ+I/sA�:�C�R$+I/$?N-�` R$&8/$+I:�H5��-�^��B7�&8CbJ'+.(8&�:6*�*g:�(gD]7 -0/u*,9$&O/$&)*BA"-0C�D/$-TR$&87)3i�9$& � � y�l � �fH.-0P�:�H�©s-0P$+.HI& &>`«-�C�*�� �fH.-]©s-

|ª9c*�*,F���m0m;A�A�Af3�R�:�C�F�:�3�MN+.Htm6+5*,-]m6C�&87�&�:�C�(g9¡m6?0H.-0MN-cm6+I/$R�&>=a3�9c*EMNH�~�� +I7 7�&8&)DT+./$?�*,-f:�R�R$CE&)7E7�7E-0MG&<-�^Q*,9�&P�:�7�+I(O&8/$?0+./$&8&)CE+./$?2+I7�7ES$&)7 +I/�CE&87�&�:�C�(g9j:�/$R�F$C�-�*,-6*BU'FQ&@R$&>J0&)HI-0F$MG&8/c*E78XW:�/$R�+I7 :6HI7E-Z:6*E*E&8MGF�*,+./$?N*E-S$7�&\e�-0Cb*,&)[8[�:�*,&)(g9$/$-0H.-0?�UO^{-0Cd(8CbU'F'*,-0?0CE:�F$9$+.(�:�F$F$C�-c:�(g9$&)7�*E-fCE&)*ECE-���*E*,+./$?f7E&)(8S$C�+.*BU�+./]*E-�*,9$&���HI-]©u-CE&)7E&8:�CE(g9s&8/cJT+ICE-�/$MN&)/c*|ª9c*�*,F���m0m;A�A�Af3�?0HI-�MN-$3�7EC�+�3�(8-0MG9c*E*EF���m�m;A�A�Af3�?�HI-0MG-$3�7ECE+}3�()-0MZm0~>3V\-KA"&)J�&8C8X$:�(g9$+I&>JT+I/$?�7E&)(8S$C�&LFQ-0C�*,:�P$HI&�()-0MNF�S�*,&)C"()-0MNM_S$/$+I(8:6*,+.-0/$7d+.7":�J0&)C�UGR$+��N()S$H.*�*,:�7ED¡X':�/$R2:;*F$C�&87E&)/c* 7E&)(8S$C�+.*BUO:�/$Rf*,-\:�H�:�C�?0&�&>=T*,&)/]*Y7ES�C�JT+.J6:�P$+.HI+5*BU�:�C�&�/�-�*�R�CE+.JT+./$?�CE&8x]S$+.CE&)MN&)/]*E7Y+./OMG-07b*Y-6^�*,9�&-0/$?�-0+I/$? � � y\l � �fH.-]©s-2C�&87E&8:�CE(g9 F$CE-�?0C,:�MG7���CE:6*,9�&8C8X�7�&8()S$CE+5*BU |ª/$-6*�*,-vMG&8/c*,+.-0/�7ES$CbJT+.J6:�P$+.HI+.*BU�~7E&)&8MG7G*E- PQ&�*,9$-0S�?09c*Z-�^ :�7q7E-0MG&)*E9$+I/�?j*E9�:6*G(�:�/§Pa&u:�R�R$&8R§H�:6*E&8C�� A�9$+I(g9§?0-'&)7G:�?c:�+./$7�*q*,9�&*,&8:�(g9$+./$?07�-�^#U0&�:6CE7�-�^�&�='Fa&)CE+I&)/$(8&�+I/�7bU'7b*,&)M�R$&)J�&8HI-�F$MN&)/c*�3i�9$&�()-0MNFQ-0/$&)/c*,7<*,9$:6*�:�C�& MN-�7�*�()CE+.*E+I(8:�HQ^{-�C<7ES$CbJT+.J6:�P$+.HI+.*BU�� :6/$R2*,9$&)CE&>^{-0CE&�R$&)7E&)C�JT+I/$?G-�^W*,9�&

MG-07�*OR$&)^{&)/$7E+5J0&2R�&87E+.?0/�XYR$&)J�&8HI-�F$MN&)/c*�Xd:�/�RMZ:6+I/c*,&)/�:�/$()&Z:6*�*,&)/]*E+I-0/� :6CE&q*BU'F�+I(�:6HIH.Uj:6S�*,9$&)/c*,+5�(�:;*,+I-�/h7E&)C�J�&8CE7)X���HI&G7E&)C�J0&)CE7)X�/�&)*BA"-0CEDj7E&)C�J0&)CE7)X�PQ-0S$/�R�:�C�Uj()-0/c*,CE-�HIHI&)CE7Z|ª+./$(8H.S$R$+I/�?�:�()(8&)7E7�(8-�/]*ECE-0HMG&8(g9�:�/�+I7EMG78X��$CE&)A�:�H.HI78X�?�S�:�CER�7g~>X�:�7GA�&)HIHL:�7Z-�*E9$&8CN(8-0MGFQ-0/$&8/c*E7Z*,9�:;*2M@S$7b*2/$&)(8&)7E7,:6CE+IH5U�PQ&�:;*HI&8:�7�*NF�:�Cb*,+I:�HIH5Uh*,C�S$7�*E&8R�3�e�CE-0M :jCE&8H.+�:�P�+IHI+5*BUhFQ-0+./]*N-�^ JT+.&)AfX���H.&s7�&8C�J�&8C�7�:�/$R�/�&)*BA"-0CED§7E&8CbJ0&)CE7

� `

Page 92: Practical Architectures for Survivable Systems and Networks (Phase

:�C�&vF�:�C�*E+I()S$H�:�C�H.Uj(8C�+.*E+I(�:6H�3pe�CE-0M :�7E&)(8S$C�+.*BU�FQ-0+I/c*�-6^\JT+I&>AfX�:�S�*,9�&8/c*,+.(�:6*E+I-0/�7�&8C�J�&8C�78X<PQ-0S$/$R$:�C�U(8-�/]*ECE-0H.HI&)CE78X$:�/$Ru(8C�UTF�*E-0?0CE:�F$9$+.(�S�/$+.*E7�M_S$7�*�CE&)(8&)+.J0&�&>=T*EC,:NF�CE-�*E&8()*E+I-0/«3"e�C�-0M :q7�UT7�*E&8M +I/c*E&8?0C�+.*BUFQ-0+I/c*<-6^�J'+.&)AfX$()C�UTF�*E-0?0C,:6F$9$+I(8:�HIH5Uq?0&8/�&8C,:;*,&8Rv+./c*,&8?�CE+.*BUG7�&�:�H.7�:�/$RvF$C�-'-6^��B(�:6CEC�UT+./$?_()-'R$& :�CE& S�7E&)^{S�H*,&)(g9$/$+.xTS�&87�*,-G9$+I/$R�&8C�S$/$R�&)*,&)()*E&8R�7bU'7b*,&)M�MN-TR$+��$(�:6*E+I-0/$7)3

��) � � "� � ��� ���������� � ��� � � �#! �Y���

%'&>J0&8CE:�H ()-0/$7E+.R$&8CE:6*,+.-0/$7L:�CE&@/�&8(8&)7E7E:�C�U�*E-2PQ&�:�P$H.&O*,-vC�&�:�R�+IH.U�()-0/���?�S$CE&@7�S$C�JT+5J�:6P$HI&@7bUT7�*,&)MN7f:6/$R/$&>*BA�-0C�D]7@-0S�*_-�^<7�S$P$7�UT7b*,&8MG783 � C�(g9$+.*E&8()*ES$C,:6HIH.U�X#*E9$&Z7�S$P$7bU'7b*,&)MN7�M@S�7�*O9�:�J0&v:�F�F$CE-0F�CE+�:;*,&�^{S$/$(��*,+.-0/�:�H.+.*BU�3§i�9$&>U�M_S$7�*Z:�HI7�- PQ&u(8-0MGF�:6*E+IP$H.&2A�+.*,9§-0/$&s:�/$-�*E9$&8C)X�:�/$R§*,9$&)+ICq+I/c*,&)C�^ª:�()&87NM@S$7�*NPQ&&�:67E+IH5U2()-0MNFQ-07E:�P$HI&63�%TUT7�*E&8M :�/$Ru/$&>*BA�-0C�DvMZ:6/�:�?0&)MN&)/]*�^ª:6(8+IH.+.*E+I&87":�C�&O:6HI7E-q()CE+.*E+I(8:�Ha*E-q*E9$&fMZ:6+I/'�*,&)/�:�/$()&_-�^�7ES$CbJT+.J6:�P$+.HI+.*BU�3�nB/sF�:�C�*E+I()S$H�:�C)X$*,9$&�(8-�/���?0S$CE:6*,+.-0/uMZ:�/$:�?0&8MG&8/c*�7�UT7b*,&8M M@S$7b*LPQ&�Pa-�*E9(8-�MNF$C�&89$&)/$7E+5J0&O:�/$Ru(8-0MGF$C�&89$&)/$7E+.P$HI&�&)/$-0S$?09�*,-qFQ&8C�MN+5*�(8-0/�7E+I7b*,&)/]*L:�R$MG+I/�+I7�*EC,:6*E+.J�&L(8-�/]*ECE-0H}3

��+.J0&)/�*,9$&�/�:6*,S�CE&�-�^�*E9$&�*,9$C�&�:6*E7�:�/$Rr/�:;*,S$CE:�H\^ª:�+.HIS$C�&87)X�+.*2+.72&87�7E&)/]*E+�:�H\*,9�:6*27�UT7�*E&8MG7s:6/$R/$&>*BA�-0C�D]7NPQ&�(�:�F�:6P$HI&v-�^�R�UT/�:6MN+.(vCE&8()-0/���?�S$C,:6*E+I-0/«X�A�+5*,9 -0C@A�+5*,9$-0S'*q9TS�MZ:�/ +./]*E&8CbJ0&8/c*E+I-0/ :�(��(8-�CER$+./$?@*,-�*,9�&�C�&�:�H ��*E+IMG&\C�&8x]S$+IC�&8MG&8/c*,7)3�i�9$+I7�+IMGF$H.+I&87�*,9$:6*�CE&)xTS�+ICE&)MN&)/c*,7�:�/$R�R�UT/�:�MG+I(�FQ-0H.+I(8+.&87M@S$7b*@:6R$R$CE&)7E7f*,9$&G/$&)&8R$7�^{-0CfCE&8()-0/���?�S$C,:6*E+I-0/p*,9$:6*_MN:�+./]*,:�+I/�7LA�9�:6*E&)J0&)CO^{S$/�()*,+.-0/�:�H.+.*BU�M@S$7�*OPQ&CE&>*g:�+./$&8R«XTA�+5*,9N:�F$F$C�-0F$CE+I:6*,&�7�&8(8S�CE+.*BUN:�/�R2CE&)HI+�:6P$+IH.+.*BU03 � :�(g9ZFa-�*E&8/c*,+I:�H�(g9�:�/�?0&L(8:�CEC�+I&87�A�+.*E9Z+5*"()&8C��*g:6+I/�+IMGF$HI+.(�:6*E+I-0/�78X]7ES$(g9�:�7�A�9$&)*E9$&8C�*,9�&�C�&87�S$H.*E+I/$?q7�UT7b*,&8M�()-0/���?�S$C,:6*E+I-0/vA�+.HIH«PQ&fHI&)7E7�7ES$CbJT+.J6:�P$H.&-0CfMG-0CE&�7�S$C�JT+.J6:�P�HI&�XY:�/$RpA�9$&>*,9$&)C_+.*�A�+.HIH PQ&q&�:�7�+I&)C�-�C�MG-0C�&GR�+��G(8S$H5*�*,-s:6*E*,:�(gD¡3 � /]*E+I()+IF�:6*E+I/$?*,9�&L(8-�/$7E&)xTS�&8/$()&87�-�^�&8:�(g92FQ-07E7�+IP$H.&\C�&8(8-�/���?0S$CE:6*,+.-0/Z+.7"&�=T*,CE&)MN&)H.UqR$+��G(8S$H5*�X]P$S�*�7E9$-0S�HIRZPQ& :�F�:�Cb*-�^#:�/cUGMG+I7E7�+I-0/T�B(8C�+.*E+I(�:6H�:�CE(g9�+.*,&)()*ES$CE&63di�9TS�78X$*,9�&8CE&L:�CE&\R$&87�+I?0/T��*,+.MN&�*g:6()*,+.(�:�HQ:�/�R27�*EC,:6*E&8?0+.(L+I7�7ES$&)7*,9$:6*ZM_S$7�*G^{-0CE&)7E&)&s*,9�&�CES�/'��*E+IMG&2*g:�(>*,+I(8:�H�:�/$R§7�*,CE:6*,&)?0+I(u+I7�7ES$&)783z%'S$(g9�(8-0/$7�+IR$&)C,:6*E+I-0/�7GA�+.HIH�PQ&F�:�Cb*,+.(8S$HI:�CEH5UN+.MNFQ-0Cb*g:�/c*<A�9$&)/$&)J�&8C\+I/�^{-0C�MZ:;*,+I-�/ZA<:6C�^ª:�C�&�+I7�:@J'+5*g:�H«(8-0/$()&8C�/�3

��)�� � ����"�¡! ������"� � �������d�]�$� � �«� � ���

i�9$&GF$CE&>JT+I-0S$7f7�&8()*E+I-0/�7O-�^"*,9$+.7�(g9�:�F�*E&8C�-0S�*EHI+I/�&�+IMGF$CE-KJ0&)MN&)/c*,7�*,9�:;*O/�&8&8Rj*,-uPa&qMN:�R$&q+I/p()-0Mq�F$S�*E&8CW7�UT7b*,&8MG7 :6/$RO+./f/$&)*BA"-0CED]+./$?\7�-�^t*BA�:�CE&63dV\-KA"&)J0&)C8X]%T&8()*E+I-0/�1$3��</$-�*,&)7#*E9�:6*W7�-0MN&d^{S$/�R�:�MG&8/c*g:�HF$C�-0P$HI&)MN7\(�:�/�/$-�* PQ&@7�-0H.J�&8R�*,9�CE-0S$?�9�Pa&>*E*,&)C 7�UT7b*,&8MG7�:�/�R�/$&)*BA"-0CED]+./$?v7E-�^t*BA�:�C�& � 7EFQ&8()+���(8:�HIH5U0X*,9�-07E&fCE&)H�:6*E+I/$?O*,-�*,9$&fS$/�R$&8C�H.UT+I/$?q+./�^{-0CEMN:6*E+I-0/N+I/�^{CE:�7�*ECES$(>*,S$C�&Z|{7ES$(g9s:�7�*,9�&�nB/c*E&8CE/�&)*\:�7�+.*�&�='+I7�*E7*,-TR�:�U�~>3q¥LJ�&8CE()-0MG+I/$?2*E9$&qHI+IMG+.*,:6*,+.-0/$7�-�^�*,9�&GnB/c*E&8CE/�&)*�+I7f:�/�&)/$-0C�MN-0S�7�S$/$R$&)C�*g:6DT+./$?$XWP$S�*f7�-0MG&R$CE:�7�*E+I(�MN&8:�7ES�CE&87GM@S$7b*ZPQ&�*g:�D6&8/�+.MNMG&8R�+�:6*E&8H.Up*E- F$C�&)J�&8/c*2*,9�-07E&uHI+.MN+5*g:6*E+I-0/$7f^{CE-�M Pa&)(8-0MG+I/�?7E+.?0/$+���(�:�/c*EH.U�A"-0CE7�&�3ui�9$&ZP�+I?0?0&)7�*OF$CE-�P$HI&)M -�^�(8-�S$CE7�&Z+I7f*,9$:6*O*E9$&ZnB/c*E&8CE/�&)*@+.7_:6/h+I/c*E&8CE/$:6*,+.-0/�:�H&8/c*E+.*BU03dnB/2©�:�Uu4K¢0¢0��XT:6*�:O9�&�:�C�+I/$?O-�^«*E9$&���3�%a3�%'&)/�:6*,&LlY&)CEMN:�/$&8/c*�%'S$PQ(8-0MGMN+5*E*E&8&�-0/ZnB/cJ�&87�*E+I?c:¤�*,+.-0/$7 |�%'&)/�:6*,&�k�-�MNMG+.*�*,&8&�-0/ ��-KJ0&8C�/$MG&8/c*g:�H � `«:�+IC�7g~�X�+I/ZHI+I?�9]*"-�^�*E&87�*E+IMG-0/cUZ-�/2R$+��G()S$H.*E+I&87�*,9�:;*&>='+.7�*_A�+5*,9PQ&8+./$?�()-0/$/$&)()*,&)R*,-�*E9$&2nB/c*,&)CE/$&>*�X�%'&)/�:6*E-0C�%�:6M  �S$/$/w| ���c�0� �X�F�:�?0&)724K�;�,404¤~�:�7ED6&8R+I/j&87�7E&)/$(8&GA�9�:6*�A�-0S�HIRj9�:�F$FQ&8/ +.^�A"&�|{*,9�&��/$+.*E&8Rh%T*g:6*E&87,~f7�+IMGF$H.U�(8S�*O-0S$C�7E&8H5J0&)7O-�`�^{C�-0M *,9�&CE&)7�*�-�^�*,9$&qnB/c*,&)CE/$&>*�3NlY&)CE9�:�F�7O9�:�JT+I/�?�:v/�:6*E+I-0/$:�H�()-0MNF�S�*,&)Cb�B()-0MGM@S$/$+.(�:6*E+I-0/�+./�^{C,:67�*,C�S$()*ES$CE&q+./:�R$R�+.*,+.-0/Z*E-@*,9$&�+./]*E&8C�/�:6*,+.-0/�:�HQnB/c*,&)CE/$&>*\+.7<+I/2^ª:6()*�:@?0-T-TRv+IR$&8:�X$:�H5*,9$-�S$?092+5*<A�-�S$HIRv/$-6*�7E-0H5J0& *,9�&F$C�-0P$HI&)M *E9�:6*q*,9$&�()-0MNF�S�*,&)C�7�UT7�*E&8MG7Z:�/�R§/$&>*BA�-�CED]+I/$?j7E-6^t*BA<:�C�&�:6CE&�/$-�*q7�&8(8S�CE&u&8/$-0S�?09�X<:6/$RA"-0S$HIRhR$&)^{&8:6*_*E9$&Z?0H.-0P�:�Hd+./�^{-0C�MZ:6*E+I-0/�+./c*,&8C�(g9�:�/$?�&2F$S$C�Fa-07�&87O-�^�*,9$&NnB/c*,&8C�/$&)*83��S'*_&>J0&8/ MG-0CE&^{S$/$R$:�MN&)/c*g:�H.H.U0X'+.^W+5*�9�:�R�?c:6*E&)A�:�U'7�:�/�RuR�+�:�H �BS$F2()-0/$/$&)()*E+I-0/$7�*E9�:6*�()-0S$HIR�PQ&f:�(8()&87�7E+IP�HI& ^{CE-�M *,9�&

� �

Page 93: Practical Architectures for Survivable Systems and Networks (Phase

CE&)7�*q-�^�*E9$&ZA"-0CEH.R�Xd+.*OA�-0S�HIR�PQ&2J0&8CbUR$+��G(8S$H5*@*,-�7�&�:�H"+.*�-�`Y3p \&>J0&)C�*,9�&8HI&)7E7)X�CE+.?0+IR�H.Up(8-�/]*ECE-0H.HI&)RF$C�+.J6:6*,&�/�&)*BA"-0CED]7�:�C�&q(8HI&8:�CEH5U�:�?0-T-'Rp+IR�&�:�3s|�%T&8&N:�HI7�- ��� �0�]X#� �61$X#������d^{-0Cf7�S$P$7E&)x]S$&8/c*�C�&8HI&>J6:�/c*%'&)/�:6*,&�*E&87�*E+IMG-0/$+.&8783�~i�9$+.7ZHI&8:�R$72S�7Z*,-�-0/�&�-�^f-0S$CNMN-�7�*Z^ª:6Cb�BC�&�:�(g9�+I/$?()-0/$()HIS$7�+I-0/$7Z-0/�-KJ0&)CE(8-�MN+./$?h*,9�&�&>='+I7b*,+I/�?

R$& ��(8+.&8/$()+I&87)3�n�*\+.7�S$CE?�&8/c*,H5Uv/$&8()&87�7,:�CbUu*E-q7ES$F$F�H�:�/c*�*,9$&f&�=�+.7�*E+I/$?qi�k<l�m6n�l�m;^t*,F�m;*,&)HI/$&>*�m6S$R�F¡m67EMO*,F7E&>*�-�^aF$CE-�*E-'()-0HI7)3YnBR�&�:�H.H.U0X0:�^{S�/$R�:�MG&8/c*g:6HIH.U�/$&>A�7�&)*�-�^QF$C�-�*,-T(8-0H.7 (8-�S$HIR�PQ&�&8/$?�+I/$&)&8CE&)R�*,-fF$CE-KJT+IR�&*,9�&G/�&8(8&)7E7E:�C�Uj7ES�C�JT+.J6:�P$+.HI+5*BU0X�7�&8(8S�CE+.*BU�XYC�&8H.+�:�P$+.HI+5*BU0Xa:�/$RjFa&)C�^{-0C�MZ:�/�(8&u|}:6HIH :;*O-�/$(8&�~>X�A�+.*E9jC�-0P$S$7b*:�S�*E9$&8/c*E+I(�:;*,+I-�/�:�7�:q^{S$/$R�:�MG&8/c*,:�H�CE&)xTS�+ICE&)MN&)/c*�3 � H.*,&)CE/�:;*,+.J�&8H5U0X¡:�^{&)A�-�^Y*,9$&�&>='+.7�*,+./$?GF$CE-�*E-'()-0HI7MG+I?09c*�PQ&f7ES$()(8&87�7�^{S$H.H.UvMG-TR$+���&)R�X$P$S'*�A"&�:�CE&f/$-6*�&8/$()-0S$C,:6?0&8Rs:6*�*,9�+I7�FQ-0+I/c*�:6*�*E9$&fHI+ID6&8H.+I9$-T-'RN-�^7EMN:�H.H�+I/�(8CE&)MN&)/c*g:�H +.MNF�CE-KJ0&)MN&)/]*E783 � H.*,9�-0S$?09�n�l�% � k :�/�Rjn�l���&8CE7�+I-0/j��:6*�*,&8MGF�* *E-�-¤J�&8C�(8-0MG&7E-�MN&�-�^«*E9$&�MN-07b*�?�H�:�C�+I/$? A"&�:�D]/$&)7E7�&878X$*E9$&)UN:�C�&\7b*,+.HIH$/$-6*�7b*,CE-�/$?_&)/$-0S$?09«3dnB/Z(8&)C�*,:�+I/GHI&)7E7�(8CE+5*,+.(�:�H(�:67E&87)X�+5*WMN+.?09c*�Pa&�FQ-07E7�+IP$H.&d*,-�S$7E&":�7ES$P�7E&)* :�F$F$C�-c:�(g9�X;F�:�CE:�MG&)*,&)CE+.[8+I/�?<*,9$&�F$C�-�*,-T(8-0H.7W:�(8()-0CER�+I/$?0H5U03V\-KA"&)J�&8C8X\+I/�*E9$&�HI-�/$?hC�S$/�X�*,9$&�7b*,CE:6*,&)?�U�-6^OC�&8F$HI:�(8+./$? *E9$&�&�=�+.7�*E+I/$?h^{S�/$R�:�MG&8/c*g:6HIH.U R$&>^{&8(>*,+.J�&F$C�-�*,-T(8-0H.7_A�+.*E9 :p/�&)A�7�&)*G-�^\7ES$CbJ'+5J6:�P$HI&�:6/$R 7E&8()S$CE&uF$C�-�*,-T(8-0H.7�MN+.?09c*q:�(>*,S�:�H.H.U Pa&vH.&87�7G()-07�*EH.U*,9$:�/�*,CbU'+./$?*,-�()-'&�='+I7�*vA�+5*,9�*E9$-07E&�F�CE-�*E-'()-0HI7G*,9�:6*v:�CE&�()HI&�:6CEH.U /$-6*vS$Fr*,-*E9$& ��-0P�3onB/r*,9�:;*A�:KU�X�+.*"A�-0S�HIR�Pa&LFa-07�7E+.P$HI&L*E-�R$&)J�&8H.-0F�9$+I?09�H.UG7ES$CbJT+.J6:�P$H.& 7E&)F�:�C,:;*,&f+I/�^{-�CEMN:6*,+.-0/N7b*,C�S$()*ES$CE&)78X$A�+.*E9FQ&8CE9$:�F$7L7�-0MG&OFQ-07E7�+IP$+.HI+5*BU2-�^ *ECES$7b*BA�-�C�*,9cU�P$S�*\9$+I?09�H.Uv()-0/c*,CE-�HIHI&)R�+./]*E&8C�-0Fa&)C,:�P�+IHI+5*BUZA�+5*,9s*E9$&�CE&87b*-�^#*,9$&�A"-0CEH.R |ª&�3�?$35X$*,9$&fnB/c*,&)CE/$&>*�~�3

��)�� ��� �T���Y! � ���"�Y�����! �#��� � ���d�«�������

nB/_?�&8/$&)C,:�H}X67bU'7b*,&)M R$&>J0&)HI-0F$MG&8/c*YF$C,:6()*,+.(8&�+I7�*,C�S$H.U�:�PcU'7�MZ:6H':6/$R_M@S�7�*YPa&�+IMGF$CE-KJ�&8R�R$C,:�MN:6*E+I(�:6HIH.U�3n�^Y7�UT7�*E&8MG7\:6CE& *,-qPQ&�(8-0/ ��?0S$C�&8RuF$CE+.MZ:�C�+IH5Uq-0S�*�-�^Y-�`¡��*E9$&>��7E9$&)H.^#(8-0MGFQ-0/$&8/c*E78X$*,9�&8/�R$&)J�&8H.-0F$MG&8/c*F$CE:�()*E+I(8&Z+I7OJT+5*g:�H�*,-�*E9$&2R$&)Fa&)/$R�:�P�+IHI+5*BUj-�^�*,9$-�7E&2()-0MNFQ-0/$&)/c*,783pV�-KA�&>J0&8C)X"+5*@+.7_/$-�*@CE&�:6HI+I7b*,+.(q*E-&>='FQ&8(>*�*E9�:6*f-0FQ&8CE:6*,+./$?v7�UT7b*,&8MG7�:�/$Rj/$&)*BA"-0C�DT+./$?�7E-�^t*BA�:�C�&qA�+.HIHY+IMGF$CE-KJ0&�R�C,:�MN:6*,+.(�:�H.H.U�3�¥�/p*,9�&-�*E9$&8C�9�:�/$R«XY-0/�(8&G7ES$P$7bUT7�*,&)MN7O9�:�J0&NPa&)&8/hR�&)J0&)HI-0FQ&8R«X�+.*�+.7f*E-'-�HI:6*,&�*,-ux]S$+IP�P$HI&G:�PQ-0S�*fP�:6RhR$&��J0&)HI-0F�MN&)/]*fF�C,:�(>*,+I()& � F�:6C�*,+.(8S$HI:�CEH5U�+.^�()-0MNF�HI&)*E&8R�7bU'7b*,&)MN7�:�/$Rp/$&>*BA�-�CED]7�:�CE&@*E-vPa&�:67E7E&)M@P$H.&8RC,:;*,9$&)C *,9�:�/jR$&>J0&8H.-0FQ&8R�3qe�S$Cb*,9$&)CEMG-0CE&6X�*,9$&�PQ&87b*OR�&)J0&)HI-0F�MN&)/]*�F$CE:�()*E+I()&�+I7�/$-�*�J�&8CbUp&)`a&8()*E+.J�&G+5^*,9�&�P$:�7E+.(f:�CE(g9$+5*,&)()*,S�CE&�+I7�/$-�*�7�S$+.*,:�P$H.&�3� C�&8()&8/c*�*,9$-�S$?09c*E^{S$H"P$S�*_7E-0MG&)A�9�:;*�7E+.MNF$H.+I7b*,+I(G:�Cb*,+.(8HI&qPcU�lY:�S$H��fC�&8&8/�� 404K¢ <+.7OA"-0C�*E9�/$-�*��

+I/�?$X]&8/c*,+5*,HI&)R � i�9$&L:�C�*"-�^W()CE&�:;*,+I/�?_CE&)HI+I:�P$HI&�7�-�^t*BA�:�CE&��BP�:�7�&8R�7�UT7b*,&8MG7<S$7�+I/$?O-�`¡��*,9�&>�B7�9$&8H5^�7E-6^t*BA<:�C�&(8-�MNFQ-0/$&)/]*E783 �r� H5*,9$-0S�?09s*E9$&@:�Cb*,+.(8HI&�+I7�(8-�/$(8&)CE/$&)RjF�CE+IMN:�C�+IH.UGA�+.*E9�:�F$F�HI+I(8:6*,+.-0/'��7�UT7�*E&8M�CE&)HI+I:�P$+IH �+.*BU�X�+5*qF$CE&)7E&8/c*E7v:p^{&>A�F$CE:�()*E+I(�:6H�?0S$+IR�&8HI+./$&87�P$:�7E&)R�-0/ �fC�&8&)/���7s4¤�¤��U0&�:6CG&�='Fa&)CE+I&)/$(8&�:6*Z%T*,CE:6*,S�7k�-0MGF$S�*E&8C83fe�-0C\&>=�:�MGF$HI&6X«+5^ U0-0Sj:�C�&@:2F$C�-'()S$CE+./$?v:�?�&8/c*�X�9�&@7ES$?�?0&87b*,7G|{A"&@-KJ0&)CE7�+IMGF$HI+5^tUu^{-�CLR$&��7E()CE+.F�*,+5J0&�F$S$C�Fa-07�&87,~�*,9$:6*�U0-0SN7E9$-0S�HIRG7E&8H.&8(>*"J�&8/$R$-�CE7"A�9�-_:�C�&\()-0MGMN+5*E*,&)R@*,-�CE&)HI+�:6P$+IH.+.*BU0X6+I/$7�+I7b*�-0/?0-T-'R�7�-�^t*BA�:�CE&�&8/�?0+I/$&)&8C�+I/$?�F$CE:�()*E+I()&<*,9$C�-0S$?09$-�S�*�XcMN:�D�&�7�S$CE&�U�-0S$C�(8-0/c*EC,:�(>*,7�(8-KJ0&)Cd*,9$&�&8/c*E+ICE&�H.+.^{&()UT()HI&�XT*,&)7�*�+./N*,9�& H�:�C�?0&�:�/$R2^{-0C�(8&�*,9�:6*�F$CE-T(8&)7E7<-�/ZU0-0S�C�(8-�/]*EC,:�(>*,-0C�78X�:6/$R2R$-0/��*�F�:�UZ-�`�J�&8/$R$-�CE7S$/c*,+.H�*,9$&>U�R$&)HI+5J0&8C�A�9�:6*�*,9�&)U�:�CE&�CE&)xTS�+ICE&)R�*,-NF$CE-TR$S$()&v|ª:�7E7�S$MN+./$?N*E9�:6*�U0-0S�9�:�J0&@7�Fa&)(8+��$&8R�*,9�&CE&)x]S$+IC�&8MG&8/c*,7�:�R$&)x]S�:6*,&)H.U�+./2*,9$& ��C�7�*�F$H�:6(8&K~�3

� �

Page 94: Practical Architectures for Survivable Systems and Networks (Phase

��) � � ��,����d��� � � � �b� �W�W�¡��� � � ���d�«�$�b���

��-'-TR�7E-6^t*BA<:�C�&�&8/$?�+I/$&)&8CE+./$?vF$CE:�()*E+I(8&_+I/cJ0-0H5J0&)7 *,9$&@S�7E&�-�^�MG-'R$S�H�:�C�R$&87�+I?0/«X«^{S$/$(>*,+I-�/�:�H :6P$7�*EC,:�(��*,+.-0/�X�A"&8H.H5��7EFQ&8(8+���&8R�^{S$/�()*,+.-0/�:�H.+.*BU�X0CE&)S$7,:�P�HI&�:�/$Rq+I/c*E&8CE-�Fa&)C,:�P$H.&<+I/c*E&8C�^ª:6(8&87)X]+I/�^{-0C�MZ:;*,+I-�/_9$+.R$+I/$? *E-MN:�7EDO+IMGF$HI&)MN&)/]*,:6*,+.-0/_R�&)*g:6+IH�X0:�/$R�*,9$&�S�7E&�-�^«:�/�:�H5U'7�+I7�*E&8(g9$/�+Ix]S$&87":�/$Rq*,-T-0H.7Y*,9$:6*�?0CE&8:6*,H5U@C�&8R$S$()&*,9�&�HI+ID6&8H.+I9$-T-'Ru-�^��¡:�A�7�:�/$R�F�CE-0?0CE:�MGMN+./$?N&)CEC�-0CE7)3���-'-TR�7�-�^t*BA<:6CE&�&8/�?0+I/$&)&8C�+I/$?vF$CE:�()*E+I()&_*,9$&)CE&��^{-0C�&G7�9$-0S$H.Rh:6HI7E-u+I/cJ�-0H.J�&q*E9$&GS$7E&G-�^<9�+I?09'��HI&>J0&8HdF�CE-0?0CE:�MGMN+./$?2H�:6/$?0S�:�?�&87�*,9�:;*_:6CE&q+I/c*,C�+I/$7�+I(8:�HIH5UHI&)7E7<7�S$7E()&8F�*E+IP$H.& *,-@(g9$:�C,:�(>*,&)CE+I7b*,+.( &8C�CE-0C�7 � 7�S$(g9�:67<MN+.7E7�+I/$?OPa-0S�/$R$7<(g9$&)(gD]78XQMN+.7EMN:6*,(g9$&)RZ*BUTFa&)7:�/$R MG+I7�MZ:6*E(g9$&8R�FQ-0+./]*E&8C�78X�-�`¡�BPcUc�B-0/$&v&)CEC�-0CE7)X�:�/�R MG+I7�7E+./$?�&>='()&8F�*E+I-0/ (8-�/$R$+.*E+I-0/�783 � 7@A�+IR$&)H.US$7�&8R :�7 *,9$&Gk�F$C�-0?0C,:6MNMG+I/$?NH�:�/�?0S�:�?0&O+I7)X�+.*�+.7�:v(8-0/c*E+I/]S�:�HY7E-0S$C�(8&q-�^�F$C�-0?0C,:6MNMG+I/$?N&8C�CE-0C�7�P]U7ED]+.HIHI&)RZF$C�-0?0CE:�MNMG&8C�7<:�7�A�&)HIH«:�7</$-KJT+I()&8783"k<:�C�&)^{S$HaR$-T(8S$MG&8/c*g:;*,+I-�/2+I7�:�HI7�-_&87�7E&)/]*E+�:�H}3�lY-�*E&8/c*,+I:�HIH5U0X*,9�&LMG-07�*"Fa-KA"&8Cb^{S$Ha*E&8(g9$/$+.x]S$&87�MN:�Uq+I/N*E9$& H.-0/$?�CES$/2+./cJ0-0H5J0&\^{-�CEMN:�H¡MN&>*,9$-TR$7L|�%'&)()*,+.-0/ �'3�¢c~�X'P$S'**,9�-07E&�*,&)(g9$/$+.xTS�&87 :6CE&�H�:6Pa-0C�+I/c*,&)/$7E+5J0&�:�/$Rs:�CE&�/�-¤A¨Pa&)(8-0MG+I/$?�M_S$(g9sMG-0C�&�&)`a&8()*E+.J�&�+./�F$C,:�(>*,+.(8&�3k�-0MGMN&)CE()+�:�Hc*,&)(g9$/$+.xTS�&87d^{-0C�7�-�^t*BA�:�CE&�&)/$?0+I/�&8&8C�+I/$?\*,&8/�Rq*E- &8MGF$9�:67E+I[)&<F$C�-'()&8R$S$C�&87d^{-0CY(8-0/c*,C�-0H5�

HI+./$?f:�/$Rq()-0/$7�*EC,:�+./$+I/�?f*E9$&���������������+./cJ0-0H5J0&8RG+I/�*E9$&�7E-�^t*BA�:�CE&�R$&>J0&)HI-0F$MG&8/c*"()UT(8H.&��YCE&8x]S$+.CE&)MN&)/]*E7&8/�?0+I/$&)&8C�+I/$?$Xc7�Fa&)(8+���(�:6*E+I-0/«Xc+IMGF$HI&)MN&)/]*,:6*,+.-0/�X¤*,&)7�*,+./$?$X]MN:�/�:�?0&)MN&)/c*�Xcx]S�:�H.+.*BU_:�7E7�S$C,:�/�(8&�X':�/$RGCE+.7EDMN:�/�:�?0&)MN&)/c*�3�i#&87b*,+./$?O+.7�+I/$9$&)CE&)/]*EH.U�+./$(8-�MNF$H.&)*E&�X0A�+.*E9�*,9$&�-0HIRG:�R$:�?0&�*,9�:;*"+5*�R$&8MG-0/$7b*,CE:6*,&)7�-�/$H.U*,9�&_F$C�&87E&)/$(8&�-6^dP$S$?07\C,:6*E9$&8C�*,9�:6/�*,9$&_:�P$7�&8/$()&@-�^�P$S$?�783L©s&)*ECE+I()7 :�C�&_FQ-0F$S$HI:�C�^{-0C\*E9$&_R�&)J0&)HI-0FT�MG&8/c*�F$CE-T(8&)7E7":�/$Rq^{-0C�:�7E7�&87�7E+I/�?_(8-TR$&�x]S�:�HI+5*BU0XcP$S'*�:6CE&�/$-�*�R$& ��/$+.*E+.J�&�3�k�-TR$&�+I/$7�Fa&)()*E+I-0/$7�:�C�&�:�HI7�-FQ-0F$S$HI:�C8XWP$S�*O/$-�*O(8-�/$(8H.S$7E+5J0&�3 � 7E7�&87�7EMG&8/c*�-�^�C�+I7�D�MZ:6/�:�?0&)MN&)/]*�+.7�+./$9$&)CE&8/c*EH.Uj:sC�+I7�D]UpF�CE-T(8&87�7|ª7�&8& ��������}X�F�:�?0&)7\� � � ����0�0~>3©�:�/cUv-6^�*,9�&�()-0MGMN&)CE(8+I:�H«7�-�^t*BA�:�CE&�&8/$?�+I/$&)&8CE+./$?�*,&)(g9$/$+Ix]S$&)7L:6CE&f7ES$F�Fa-0Cb*,&)R�PcU�:�S�*E-0MN:6*,&)Ru-�C

7E&)MN+I:�S�*E-0MZ:;*,&8R�*E-'-0H.7832nB/�R$&8&)R�X�*,9�&Z-0/$&)7�*E9�:6*_:�CE&G/$-�*O7ES�F$Fa-�C�*,&)RPcUjMN&)(g9�:�/$+.(�:�Hd*,-T-0H.7f:�CE&G-�^J0&)C�UuHI+.MN+5*,&)R2J�:6HIS$&63�i�9$&�S$7E&O-�^ 7�-�^t*BA�:�CE&O&8/$?0+./$&8&)CE+./$?G*E-'-�HI7�(�:6/�PQ&_:�R'J�:6/]*,:�?0&)-0S$78X¡F�:6C�*,+.(8S$HI:�CEH5U+I/ R$&)*E&8(>*,+I/�?�*,9$&2(g9$:�C,:�(>*,&)CE+I7b*,+.(Z&8C�CE-0C�7_/$-6*,&8R :6Pa-KJ0&63p¥ /$&2-�^�*E9$&ZMG-07b*@S$7�&)^{S$H�*,-T-0HI7�+I/C�&8()&8/c*U0&8:�CE7�+.7L*,9�&������������ F$CE-0?�C,:�MuXaA�9$+.(g9�R$&)*E&8(>*,7f?c:�C�P�:�?0&O(8-0H.HI&8(>*,+.-0/�F$C�-0P$H.&8MG7LCE&)7ES$H5*,+./$?Z^{CE-�M S$/T�^{CE&)&8Rq7�*E-0C,:6?0&�3�V\-KA�&>J0&)C8XT-¤J�&8C�CE&8H.+�:�/�(8&<-0/�7�S$(g9q*,-T-0HI7Y(�:�/�C�&87ES�H.*d+./�7E&8C�+I-0S�7 CE+.7ED]7d+I/_*E9$&�:�P$7�&8/$()&�-�^9]S$MN:�/Z+./]*E&8H.HI+I?�&8/$()&�3 e�S$Cb*,9$&)CEMG-0CE&6X'-KJ�&8CE&)MNF�9�:�7E+.7�-0/N*,9$&\F$CE-T(8&)7E7E&)7<C,:;*,9$&)C"*,9$:�/2-0/G*,9$&\CE&8x]S$+.CE&��MG&8/c*,7)X0*,9$&<R�&87E+.?0/$7)X]:�/$R@*,9�&<+IMGF$HI&)MN&)/c*g:6*E+I-0/$7�*E9$&8MG7E&)H.J0&)7�(�:�/�PQ&<MG+I7EH.&�:�R�+I/$?$3W �-�*d7�S$CEF$C�+I7�+I/$?0H5U0X*,9�&���&�:�C��b���0����l�C�-0P$H.&8M +I7<^{-0C�(8+I/�?�:�CE&)*E9$+I/�DT+./$?�-�^#M@S$(g9�-�^#*,9�&�-0HIR'��7�*BUTHI&L(8-0/cJ0&)/c*,+I-�/�:�H�A�+I7�R$-0MCE&)H�:6*E+I/$?�*,-�7�-�^t*BA<:6CE&f&8/$?�+I/$&)&8CE+./$?$3 i�9�-07E&�A�9$-�*g:6D�& *,9�& (g9�:�H.HI&8/�?0& 7E&)CE+.-0S$7EH5U2:6CE&�HI+.D�&)H.Uq*,-�C�&�:�H.+I[8&*,9�&v/$&8&)R ^{-�C@C,:�R�+I(�:6H�(g9�:�/�?0&v+I/�MN:�D]+I/$?s*,9$&v7�-6�B(8:�HIH.&8R7�-�^t*BA<:6CE&v&8/�?0+I/$&)&8C�+I/$? ��&)HIR�MG-0CE&Z-�^\:�/&8/�?0+I/$&)&8C�+I/$?qR$+.7E(8+.F$HI+./$&�3<|�%'&)&_:�F$C�-KJ0-T(�:6*E+.J0&�:�Cb*,+.(8HI&LP]U � :�JT+IRulY:�CE/�:67�����£ ���-0/�*,9�:6*�7�S$P���&)()*�3�~�\7�&N-6^�*,9�&N-0P ��&8()*b�B-0C�+I&)/]*E&8R F�:�C,:6R$+I?0M +I/p*,9$&G7�UT7b*,&8M R$&)7E+.?0/h+5*,7E&)H.^"MZ:�U�PQ&GPa&)/$& ��()+�:�H\|{F�:�Cb�

*,+.(8S$HI:�CEH5UZA�+5*,9�C�&87�Fa&)()* *E-Z7�UT7b*,&8M +I/c*,&)?0CE+5*BU�~>X�^{-0C�&>=�:�MGF$HI&6XQ()CE&8:6*,+./$?2:GH�:�U0&)CE&8R�7�UT7�*E&8M +./uA�9�+I(g9&�:6(g9rH�:�U0&)CN(8:�/�PQ&�HI-T-0D6&8R�S�Fa-0/�:�72:j7�*,C�-0/$?0H5U�*BUTFa&)Rr-0P���&8(>*2MN:�/�:�?�&8C8X<:�7Z+./§*,9�&�l�%$¥f%§R$&��7E+.?0/ � 4K�c�'X<���0� �3�i�9�:;*vF�:�CE:�R$+I?�M ()-0M@P$+./$&87N^{-0S$CZF�CE+I/�(8+IF�HI&87N-�^�?0-T-'R§7E-�^t*BA�:�CE&�&)/$?0+./$&8&)CE+I/�?� :�P$7b*,CE:�()*E+I-0/�XW&)/$(�:�F�7ES$HI:6*,+.-0/�XW+I/$9�&8CE+5*g:�/�(8&�X#:�/�R FQ-0H.UTMG-0CEF�9$+I7�Ms3@nB/�9$&8C�+.*g:6/$(8&q+I7�*E9$&q/$-�*,+.-0/�*,9�:;*CE&)H�:6*E&8R�()H�:�7�7E&87�-�^Q-0P ��&8()*E7�Pa&)9�:�J0&�7E+.MN+.H�:�C�H.U0X6:�/$R@*E9�:6*�7�S$Pa()H�:�7�7E&)7�7�9$-0S$H.Rq+I/$9$&)CE+5*�*,9�&�F$CE-0FQ&8C *BUTFQ&PQ&89�:�JT+I-0Cd-6^a*E9$&8+.C�:�/$(8&)7�*E-0CE7 ��+.*d:�HIH.-¤A�7dC�&8S$7E:�P$+.HI+.*BUO-�^a(8-TR$&�:�(8C�-07E7�C�&8H�:;*,&8Rq7b*,CE-�/$?0H.UO*BUTFa&)RZ(8HI:�7E7�&87)3lY-�H.UTMN-�CEF$9$+.7EM +I7L*E9$&@/$-6*,+I-�/�*,9�:6*�:2(8-0MGF$S�*,:6*,+.-0/�:�H#CE&)7E-0S$C�(8&�(8:�/j:�(8()&8F�*�:�C�?0S$MG&8/c*,7�-6^"R�+.`a&8Cb�&8/c*f*BUTFa&)7_:;*fR$+.`a&8C�&8/c*f*,+IMG&87)XW:�/$Rj7�*E+IHIHYCE&)MZ:�+./�*BUTFa&G7,:6^{& �Y+5*fFa&)CEMG+.*E7 F$CE-�?0C,:�MGMG+I/$?2?�&8/$&)C,:�H.+.*BU:�/$Ru7E-6^t*BA<:�C�&OC�&8S$7�&�3f| � CE&8()&8/c*\&)`a-0C�*�*,-GMG-'R$&)H�R�UT/�:�MG+I(8:�HIH5UN*BUTFQ&8R�:�(8()&87E7\(8-0/c*ECE-0H.7�+.7�?0+.J�&8/uP]Ui�+IR�7�A"&8HIHW:6/$R�l#-�*E*E&8C ���c� ��}3�~

���

Page 95: Practical Architectures for Survivable Systems and Networks (Phase

�\H5*,+.MZ:6*E&8H5U0X0*,9�& (g9$-0+.(8&87�-6^�A�9$+I(g9v-�^WMN:�/cUNR$&)J�&8HI-�F$MN&)/c*�MN&>*,9$-TR$-0H.-0?0+I&)78Xc*,&)7�*E+I/$?_*E&8(g9$/�+Ix]S$&87)X:�/$R�:�7E7�S$C,:�/�(8&�MG&)*,9�-'R$7Z:�CE&�S$7E&)Rr+I7Z/�-�*2F�:6C�*,+.(8S$HI:�CEH5U (8C�+.*,+.(�:�H}3 � 9�:6*2+.7ZMG-07�*Z+IMGFa-�C�*g:6/]*G+.7*,9$:6*G7E-�^t*BA�:�CE&uR$&>J0&8H.-0F$MG&8/c*NMZ:�/$:�?0&8C�7�S$/$R$&)CE7b*g:�/$R§*,9$&�R$&>J0&8H.-0F$MG&8/c*NF$CE-T(8&)7E78X"*,9�:6*GR$&)7E+.?0/$&8C�7S$/$R�&8CE7b*g:�/�RG*E9$&<^{S$HIHT+IMGF$H.+I(�:;*,+I-�/$7W-�^¡*,9$&)+IC R$&)7E+.?0/$78X]:6/$R@*,9�:;*�+IMGF$HI&)MN&)/]*E-0CE7#CE&)7EFQ&8(>*�*E9$&�+I/c*E&8?0C�+.*BU-�^¡*,9�&<R$&87�+I?0/�7 A�9$&8/�*,9�-07E&�R$&)7E+.?0/$7�:�C�&�:�R$&)xTS$:6*,&�P$S'*d*,9�:6*�*,9$&>U�:�H.7E- C�&8(8-�?0/$+I[)&�A�9$&)/G*E9$&<R$&)7E+I?�/$7:�C�&�^ª:6S$H.*BU�3#i�9�&"MG&)*E9$-'R�7Y:6/$R�*,-T-0HI7�(8:�/O?�-�-�/$H.UL7E-�^ª:�C83#nB/$&)JT+5*g:�P$H5U0X¤+.*W+.7�*,9$&�FQ&8-0F�HI&�+I/�*,9�&�F�CE-T(8&87�7*,9$:6*�MZ:;*E*,&)C8X�:6/$Ru*E9$&)U2(�:�/$/�-�*�Pa&�:�S�*E-0MN:6*,&)R�3

� �������� ��������� �� ������ ��� ���� ��� ���� �� ����4�}X]: Fa-�*E&8/c*,+I:�HIH5U�S$7E&>^{S$H�CE&)(8&8/c*"Pa-T-0Df^{CE-0M¦*,9$&\k<:�C�/$&8?�+I&>�©s&)HIHI-�/ ��/$+.J�&8C�7E+.*BUN%T-�^t*BA<:6CE& � /�?0+I/$&)&8C�+I/$?�nB/$7�*E+.*ES�*,&6XT()-0/$7�+IR$&)CE7�*,9$&�P$S$7�+I/$&)7E7�(>UT(8HI&�:�/�RZ-0C�?c:�/$+.[�:;�*,+.-0/�:�Ha^{-0CE()&87�Pa&)9$+I/$R�7�-�^t*BA<:6CE&@:6CE(g9$+5*,&8(>*,S$C�&�3�n�*�F$CE&)7E&8/c*E7�:�MZ:�/$:�?0&8MG&8/c*b�B-0C�+I&8/c*E&8RvJT+I&)A¨-�^�7�-0MG&-�^#*,9$&fF$C�-0P$H.&8MG7<*,9�:6*�A"&�(8-0/$7�+IR$&)C�9$&8C�&�3

����� � ��� � � �T���#! � "! �_���� � �b�b�B� �

l�:6CE/�:�7 ���0�TX$�0�6£'X����0�TX��0��¢�X���£0£TX���£�¢'X���£0��X���£0�TX���£�46X$�6£ �'X���£c�TX$��£c� d|{HI+I7b*,&)R2(g9$CE-�/$-0HI-�?0+I(8:�HIH5U$~ :6/$R� + ��D]7b*,C,: ��¢ ��X$¢�1�X�¢ ���9�:�J0&�^{-0C�MZ:�/cUNU0&�:6CE7�A�CE+5*E*,&)/�&>=T*,&)/$7E+5J0&8H5U�-0/v*,9$&�MG-TR$S$H�:6C�R$&)(8-0MGFa-�7E+.*E+I-0/-�^_7�UT7�*E&8M R$&)7E+I?�/$783 | ��:�C�+I-0S$7v-6*,9$&)Cs:6S�*,9$-�CE7�9�:�J0&jA�CE+.*�*,&)/wMG-0C�&jC�&8()&8/c*,H5U -0/w*E9$+I7v7�S$P���&)()*�3�~�\/'^{-0C�*ES$/�:6*E&8H.U�X6MG-07b*Y()-0MGMN&)CE(8+I:�H�7bUT7�*,&)MN7�:�CE&�7E&)CE+.-0S$7EH5U�H�:6(gDT+./$?�+I/f*,9$&)+IC#:�C�(g9$+.*E&8()*ES$C,:6HT7b*,C�S$()*ES$CE&63i�9$&�&>`«&)()*,7�-6^YMG-TR$S$HI&\(8-0MGFQ-07E+5*,+I-�/Z-0/2*E9$&�(8-0C�CE&)7EFQ-0/$R$+./$?�7E&)(8S$C�+.*BU2MG-TR$&8H.7�9�:�J0&fPQ&8&)/u7b*,S$RT�

+I&)R�&�='*E&8/$7�+.J�&8H.Uu+./�CE&)(8&)/]*\U0&8:�CE7q|{&�3�?$35X ����X¡1c��XW4¤�6¢'XW4K¢c�'XW4K¢ �TX#4K¢0�'XW4K¢0�TX#4K¢0£'Xa���0�TX«�'4 �'X �c���TX � �0�'X�c���TX �0¢�1'X �0¢ � t~�3�nB/jMN:�/cU�(8:�7E&)78XW9$-KA�&>J0&)C8X�7�&8&)MN+./$?0H.U�7�*EC,:�+.?09c*E^{-0CbA<:�C�R�(8-0MGFQ-07E+5*,+I-�/$7 9�:�J0&qS$/T�F$C�&8R$+.()*,&)R�7E+IR�& &)`a&8(>*,78X�+I/27�-0MN&L+I/$7b*g:�/$()&87�+./]*E&8Cb^{&8CE+./$?_A�+5*,92-0/�&f:�/$-�*E9$&8C)3�| � (8:�7E& -6^Y7�S$F$FQ-07E&)R$H.U+I/�R$&8FQ&8/$R�&8/c*L()C�UTF�*E-0?0C,:6F$9$+I(�7�&8()S$CE+5*BU�F$CE-�*E-'()-0HI7�+./c*,&8CE:�()*E+I/$?�S�/$7E&)(8S$C�&8H.U�+.7�?0+.J�&8/uPcU � 4 � � }3�~nB/G-�*,9$&)Cd&)`a-0C�*E7�HI&87�7�7EFQ&8(8+���(�:6HIH.U_CE&)H�:6*E&8R�*,-�7E&)(8S$C�+.*BU0Xc*E9$&8C�&\9�:67�PQ&8&)/N()-0/$7�+IR$&)C,:�P$H.&�CE&)7E&�:6CE(g92+./

(8-�M@P$+I/�+I/$?vMG-'R�&8HI7)X«*,9�&8-0C�+I&87)XW&8x]S�:6*E+I-0/�:6Hd:�/$Rj-�*,9�&8CfHI-0?�+I(87)X«*,&)CEM��BC�&)A�CE+5*,+./$?27�UT7b*,&8MG78X�:�/$RpR�:6*,:7�*ECES$(>*,S$C�&87)3"V�-KA�&>J0&8C)X�MG-07�*�-6^a*E9$&87�&\&>`«-0Cb*,7�9�:�J0&\(8-0/�7E+IR�&8CE&)RG*E9$&�7E+.MNF$H.&87b*d^{-0CEMG7d-�^a(8-0MGFa-�7E+.*E+I-0/|ªF$:�C�*E+I(8S�H�:�C�H.U�*,9$-07�&"+./cJ0-0H5J'+./$?�7E&)CE+�:6H09$-T-0D]S$F$7WA�+.*,9�-0S�*W^{&8&)R$P�:�(gD'~Y:6/$R�*E9$&�&)`a&8()*E7#*E9�:6*#CE&)7ES$H5*W^{CE-0M7E+.MNF�HI&�()-0M@P$+./�:6*E+I-0/$7#-�^QFQ-0HI+.(8+I&)7Y-�C MN-TR$&)HI7��6*,9$&)7E&�&)`a-0Cb*,7d9�:�J0&�-6^t*,&8/�PQ&8&)/q&>=T*,C�&8MG&8H.U�*,9�&8-0C�&)*,+.(�:�H� A�+.*E9 /�-�*�M@S$(g9 :�F$F$H.+I(�:6P$+IH.+.*BU�*,-uCE&8:�Hd7�UT7�*E&8M /$&)&8R$7�7ES$(g9:�7�*,9$&q+IMGF$H.+I(�:;*,+I-�/$7\-6^<(8-�MNFQ-07E&)R+IMGF$H.&8MG&8/c*g:6*E+I-0/�783

� 9$&)/�?0CE&8:6* (8:�CE&@9$:�7 PQ&8&8/�*,:�D�&)/�*,-v:6(g9$+I&>J0&�+I/c*E&8CE-�Fa&)C,:�P$H.&_MG-'R�S$H�:�C�+.*BU�X�MN-TR$S$HI:�C\()-0MGFa-07�+5�*,+.-0/�+.7\C�&8HI:6*,+5J0&8H5U�7�*EC,:�+.?09c*E^{-0CbA<:�C�R�3L©s-0CE&O(8-0MGMG-0/$H.U�X�9$-KA�&>J0&)C8X�(8-�MNFQ-07E+5*,+.-0/s+.7\/�-�*�:�/�� ���� ���� R$&)7E+I?�/h(8-�/$7E+.R$&8CE:6*,+.-0/�XY:�/$Rh()-0MGFa-07E:�P$+.HI+.*BUsMN:KUpPQ&qJ0&8CbUhR�+��G(8S$H5*�3NnBR$&�:�H.H.U�XY+5*O7�9$-0S$H.RhPQ&NFQ-07�7E+5�P$H.&�*E-Z(8-�/���?0S$C�&@:G7EFQ&8(8+���(�7�UT7�*E&8M (8:�F�:�P�HI&�-�^d:6*�*g:�+./$+I/�?q*E9$&_R�&87E+.CE&)R |ª7�S$P¡~b7�&)*L-�^dCE&)x]S$+IC�&8MG&8/c*,7)XF�:�CE:�MG&)*,C�+I(8:�HIH5Us*,:�+IH.-0CE&)Rp*E-s&8:�(g97�Fa&)(8+��$(2:�F$F�HI+I(8:6*,+.-0/�3qnB/c*,&)?0C,:6*E+I-0/j-�^<*E9$&G(g9$-07E&)/(8-�MNFQ-0/$&)/]*E77E9�-0S$HIRjPQ&N:;*E*g:6+I/�:�P�HI&_A�+5*,9pMN+./$+IM_S$M &)`a-0C�*8X#A�+5*,9pCE&)7EFQ&8()*�*,-�R$&)7E+.?0/�X#+IMGF$HI&)MN&)/]*,:6*,+.-0/�Xa-0Fa&)C,:;�*,+.-0/�XY:�/$RMN:�+./]*E&8/�:6/$(8&63�k�-0MGFQ-07E+5*,+I-�/j7�9$-0S$H.R:�R�R$CE&)7E7_*E9$&Z+./$(8-0C�Fa-�C,:6*E+I-0/j-�^�H.&87E7�*,C�S$7�*BA"-0C�*E9cU(8-�MNFQ-0/$&)/]*E7�|ª&63�?�3.X�:�7O+I/ �U'[8:�/c*,+./$&v:�?0C�&8&)MN&)/]*g~_:�7�A�&)HIH<:67@(8-0MGF$C�-0MN+.7E&G-�^�*,C�S$7�*BA"-0Cb*,9cU()-0Mq�FQ-0/$&8/c*E783 � 7_:�F$F$H.+I(8:�P$HI&6X�(8-0MGMG-0/ S�7E&)^{S�H"MG+IR$R�HI&)A�:�C�&�(8-0MGFa-�/$&8/c*,7O7E9$-�S$HIRjPa&N+IR$&)/c*,+��$&8Rp^{CE-0MA�9$+.(g9u7�S$C�JT+5J�:6P$HI& 7bUT7�*,&)MN7�(8:�/�MN-0C�&LC�&�:�R$+.H.UNPa&�()-0/���?�S$CE&)R � +I/2*,9�& 7E&)/$7E&�-�^Y:_JT+IC�*ES�:�Ha7ES$CbJ'+5Jc�:�P$H.&O*ECES$7b*,&8Rp()-0MNF�S�*,+./$?2P�:�7�&@*,9�:;*�(�:�/�7�S$C�JT+5J0&�(8&)C�*,:�+I/�*E9$CE&8:6*,7 R�&87EF�+.*,&@*E9$&@F$C�&87�&8/$()&G-6^�:2H.&87�7*,C�S$7�*BA"-0Cb*,9cU2S$/�R$&8C�H.UT+I/$?_-0Fa&)C,:6*E+I/$?O7�UT7�*E&8Mu3"%TUT7�*,&)M :�R$:�F�*g:6P$+IH.+.*BU�S$/�R$&8C�FQ&8C�(8&8+5J0&)R2*,9$C�&�:6*E7<MZ:�U:�H.7E-qPa&�S�7E&)^{S�H�3

� �

Page 96: Practical Architectures for Survivable Systems and Networks (Phase

� *d*,9�& � +.?09c*,9 � k�© %'n ��¥�l�% � S$C�-0Fa&8:�/ � -0C�D]7E9$-0FG+I/N%'+./c*,C,:'XclY-0Cb*,S$?0:�H�Xc+./Z%T&8F�*E&8M@PQ&8C�4K¢0¢�£|ª7�&8& ���61 t~�X�:uC,:6*E9$&8CO:�A�D]A�:�C�RR$&8P$:6*,&G*,-T-0D�F$HI:�(8&632i�9$&Z7b*g:6*E&8Rh:�CE?0S�MN&)/]*�A�:�7O*E9�:6*f*,9$&NR$&)J�&8H �-0F$MG&8/c*N-�^ C�-0P$S$7b*2R$+.7�*ECE+IP�S�*,&)R§7bU'7b*,&)MN7Z^{C�-0M (8-�MNFQ-0/$&)/]*E7N+.7 � � ����� ���� � 4 � � }3 � H5*,9$-�S$?09��E:MN:�CE?0+./�:�H�MN: ��-0C�+.*BU�R$+.7,:�?�CE&8&)R��_A�+5*,9Z*E9$+I7�F$CE-�Fa-07�+.*E+I-0/�Xc*E9$&8C�& :�C�&L7�*ECE-0/�?�:�CE?�S$MN&)/c*,7"*E9�:6*�&8MG&8CE?�&^{CE-�M *E9$&qR$+I7�(8S$7�7E+I-�/�Pa&8:�CE+./$?v-0/�A�9cU�(8-0MGFQ-07E+5*,+I-�/�+I7L/$-�*f7�*EC,:�+.?09c*E^{-0CbA<:6CER�+I/p:6/]U�CE&8:�HI+.7�*,+.(_7�+.*��S�:6*E+I-0/�783jV\-KA"&)J0&)C8X":�R$&8&)Fa&)Cq(8-0/$()HIS$7�+I-0/ *,9�:6*@MN+.?09c*@PQ&2R$C,:�A�/�^{CE-�M *E9�:6*�R$&)P�:6*E&v+I7_*E9�:6*@A"&M@S$7b*ZA"-0CED§M@S$(g9�9$:�CER$&)CZ*,-h&87�*,:�P$H.+I7E9�(8CE+5*,&)CE+�:pS$/$R�&8C2A�9$+.(g9�(8-0MGFQ-07E+5*,+I-�/§R$-T&87Z/$-�*2()-0MGF$CE-6�MG+I7E&�C�-0P$S$7b*,/$&)7E7)X«:�/�RsFQ&8C�9�:�F$7�&)J�&8/�&)/$9�:�/�(8&87\+.*�� :�7�7�S$?0?0&)7�*,&)R�PcUv*,9�&�/�-�*,+.-0/�-�^ ?0&)/$&8CE:�HI+.[8&)RR$&)Fa&)/$R$&8/�(8&�3

��� � ��¡! ��� � ����� ����

����� � �� �������� � � �� � � ��� ������� ����� �� � ��� � ���� � � ����� � � ����� � ���� ����������� � � ��� ���� � ���� � � � �������� � ��� � ��� �� � �� � ���"-0P <:�C�*E-0/�X¡©s:KUp4�¢0� � � ����

e�-0CEMN:�HWMG&)*,9�-'R$7�(8:�/pF$H�:�U�:�/�+IMGFQ-0C�*,:�/c* CE-�HI&_+./�*,9$&q:;*E*g:6+I/$MG&8/c* -6^"7bUT7�*,&)MN7�:�/�Rj/�&)*BA"-0CED]7*,9$:6*@M@S�7�*�:6(g9$+I&>J0&2?0&)/$&8CE:�HI+.[8&)R7ES$CbJT+.J6:�P$+.HI+.*BU�XY+./h7�Fa&)(8+��$(�:6*E+I-0/�X�R$&87�+I?0/�X :�/$R&�=�&)(8S�*E+I-0/«3��CE&�:;*+IMGF$C�-¤J�&8MG&8/c*,7�+./G7bUT7�*,&)M Pa&)9�:�J'+.-0C�(�:�/NPa&�C�&�:�H.+I[8&)R�A�9$&8/G*,9$&�CE&)xTS�+ICE&)MN&)/c*,7\|ª7�S$(g9v:�7�7ES�C�JT+.J6:�P$+.H5�+.*BU�Xc7E&)(8S$C�+.*BU0XT:�/�RGC�&8H.+�:�P$+.HI+5*BU$~�9�:�J�&\:L^{-�CEMN:�H�P�:67E+I7)3d%'+.MN+.H�:�C�H.U�X;&)/$-0C�MN-0S�7dPa&)/$& �$*E7�:�CE+.7E&�A�9$&)/$&)J�&8CR$&)7E+I?�/v7EFQ&8(8+���(�:;*,+I-�/$7�9�:�J0&f:_^{-0C�MZ:6HaP�:67E+I7 � &87�Fa&)(8+�:6HIH.UG+5^#*E9$&)U2:�CE&LR$&8C�+.J0&)Rv^{CE-0M A�&)HIH �B7EFQ&8()+���&)RCE&)x]S$+IC�&8MG&8/c*,7 CE:6*,9�&8CY*E9�:�/_*E9$&�()-0MGMN-0/OF$C,:6()*,+.(8&"-�^�PQ&8+I/�?L&87b*g:�P�HI+I7�9$&8R@:6^t*,&)CY*,9�&�^ª:�()*#*,-LCE&8F�CE&87�&8/c*:�/Z:�RN9�-'(\:�7E7�&8M@P�H.UG-�^�:6HICE&8:�R�Uc�BR�&)J0&)HI-0FQ&8RN7E-�^t*BA�:�C�&�|ª7�-0MG&)*,+.MN&)7dCE&>^{&8CEC�&8RZ*E-@:�7�F$S�*�*,+./$?�*E9$&�(�:�Cb*PQ&)^{-0C�&_*,9$&�9�-0CE7�&K~>3Oe�-0CEMN:�H#R$&87�+I?0/�J�&8C�+���(8:6*,+.-0/�*,9$&)/p+I/cJ0-0H5J0&)7 ^{-0CEMN:�H#R$&8MG-0/$7b*,C,:;*,+I-�/$7\*E9�:6*�*,9�&7EFQ&8()+���(8:6*,+.-0/$7�:6CE& ()-0/$7E+.7�*E&8/c*�A�+.*E9Z*,9$&)+IC<C�&8x]S$+.CE&8MG&8/c*E78X$F$C�-KJ'+.R$+I/�?@/$-�HI&)7E7�*E9�:�/vC�&8x]S$+IC�&8R � :6/$R*,-v*E9$&�&>=T*,&)/c*O*E9�:6*�*,9�&N:6P$7E&)/$(8&q-�^"iYC�-��E:�/p9$-0C�7E&)7O(8:�/pPa&qR$&)MN-0/�7�*,CE:6*,&)R�X�/$-�*E9$+I/�?uS�/$&>='FQ&8()*E&8R*,9$:6*<MG+I?09c*�PQ&L9�:�C�MG^{S�H�3 ��&)CE+���(�:6*E+I-0/N-�^�R$&)7E+.?0/$7<+.7"R$+��G(8S$H5*"^{-0C�7�UT7b*,&8MG7<*,9$:6*"A"&8C�&�/$-�*"R$&87�+I?0/�&8R*,-uPQ&NC�&�:�R$+.H.Up:6/�:�H.UT[)&8R�X#P$S�*O(�:�/ /$&)J�&8Cb*,9$&)HI&87�7@PQ&qJ6:�H.S�:�P$H.&q+I/pHI&)?c:�()Up7bUT7�*,&)MN72|}:�7�+I/j:�/$:�H.UT7E&)7-�^�*,9�&�CE+I7�D]7f:�7E7�-'()+�:6*E&8R�A�+.*E9�*,9$& ��&8:�Cb�����0�0�ZF�CE-0P$H.&8MZ~>3�e�+./�:�HIH5U0Xa:�H.*E9$-0S$?�9�+.*�+.7 HI&)7E7�()-0MNMG-0/$H5UF$CE:�()*E+I(8&)R2+I/N7E-�^t*BA�:�C�&�X'^{-�CEMN:�H¡(8-TR$&\J�&8CE+���(�:;*,+I-�/Z(�:6/2R$&8MG-0/$7b*,CE:6*,&�*,9�:6*<:O?0+5J0&)/2+IMGF$HI&)MN&)/c*g:6*E+I-0/+I7�(8-0/$7�+I7b*,&8/c*�A�+.*E9�+.*,7�7EFQ&8(8+���(�:;*,+I-�/$783�e�-0C�MZ:�HQ9�:�C�R�A�:�CE&�J0&)CE+���(�:6*E+I-0/v+.7<PQ&8+I/�?�S$7E&)Rs+./$(8C�&�:�7�+I/$?0H5U0X:�/$RNR$&8MG-0/$7b*,CE:6*,&)7�*E9$&\FQ-�*E&8/c*,+I:�H�&)`a&8(>*,+.J�&8/$&)7E7<-6^«^{-0C�MZ:�H�MG&)*E9$-TR$7dA�9$&8C�&\*,9�&8CE&L:�CE&�()-0/$7E+.R$&8CE:�P$H.&CE+.7ED]7O| ��/$:�/$(8+I:�H�-0C�-6*,9$&)C�A�+I7�&K~<-�^Y+IMGF$CE-�Fa&)C<R$&87�+I?0/s:�/$Ru+IMGF$H.&8MG&8/c*g:6*E+I-0/«3

��:�C�+I-0S$7�^{-�CEMN:�H�MG&)*E9$-'R�7#(8:�/_PQ&dJ6:�HIS�:6P$HI&d+./�7�Fa&)(8+5^tU'+./$?�:�/$R_:�/�:�H5U'[)+I/$?�C�&8x]S$+.CE&8MG&8/c*E78X�R�&87E+.?0/$7)X:�/$Rh+IMGF$HI&)MN&)/]*,:6*,+.-0/$7)XY:67_A�&)HIH":�7_+./h()-0MNFQ-07�+.*,+.-0/�:�H.+.*BU�3�¥L^�F�:�C�*E+I()S$H�:�Cf+.MNFQ-0C�*,:�/$()&N+./h(8-�/$/$&8(��*,+.-0/@A�+.*E9�7ES$CbJT+.J6:�P$+.HI+.*BUO:�C�&<*,&)(g9$/$+Ix]S$&)7�*E9�:6*d(8:�/qF$CE-KJT+IR�&<^{-0CEMN:�H�C�&8HI:6*,+.-0/$7E9�+IF$7YPa&>*BA�&)&8/ZR�+.`a&8CE&)/c*H�:�U�&8CE7_-�^\:�P$7�*EC,:�(>*,+.-0/ � A�+5*,9C�&87�Fa&)()*�*,-�CE&8x]S$+.CE&)MN&)/]*E7q:�/$R�7�Fa&)(8+��$(�:6*E+I-0/$7_:�HI+.D�&63�i�9$&vS$7�&2-�^^{-0C�MZ:�HQMG&)*,9�-'R$7"+I7<C�&8()-0MNMG&8/�R$&8Rv+./2F�:�Cb*,+I()S$H�:6CEH.Uq()CE+5*,+I(8:�HQ:�F$F$H.+I(8:6*,+.-0/$78XT:�/�Rv(�:�/�9$&)HIF2MG-KJ0& *,9�&(8S�CECE&)/c*\9�+I?09$H5UZS�/$F$CE&)R$+I(>*g:�P�HI&f:�R�9$-T(�R$&)J�&8H.-0F$MG&8/c*�F$CE-T(8&)7E7�+I/c*,-G:@M@S�(g9sMG-0CE&LF$CE&)R$+I(>*g:�P$H.& ^{-0Cb�MN:�HaR�&)J0&)HI-0F�MN&)/]*�F�CE-T(8&87�783�nB/2*,9$&�H.-0/$?@C�S$/�X$S�7E&�-�^#7ES�(g9u*E&8(g9$/$+.x]S$&87�(�:6/vR$C,:�MN:6*E+I(�:6HIH.U@R$&8()CE&�:67E&*,9�&OC�+I7ED]7�-�^d7bU'7b*,&)M ^ª:6+IHIS�CE&�3�k�-0/c*,CE:�C�U�*E-NFQ-0F$S$HI:�C�M_U]*,9�X���S$R�+I(8+.-0S$7�S$7�&O-�^�^{-0CEMN:�H�MG&)*E9$-'R�7\(8:�/:�H.7E-�R�&8(8C�&�:�7�&2*,9$&N-KJ0&8CE:�HIH�R$&>J0&8H.-0F$MG&8/c*q:�/�R-0FQ&8C,:;*,+I/�?�(8-�7�*,7 � &87�Fa&)(8+I:�HIH5U�A�9$&8/*E9$&Z()-07�*E7@-�^:�PQ-0C�*E&8RGR$&)J�&8H.-0F$MG&8/c*,7L|ª7�S$(g92:�7d*E9$&\(8:�/$()&8HIHI:6*,+.-0/$7 -6^a*E9$&\n�y\%aX]e �L� X]e �n�7bU'7b*,&)MN7�/$-�*E&8RG+I/Z%'&8(��

���

Page 97: Practical Architectures for Survivable Systems and Networks (Phase

*,+.-0/Z1�3 �c~�:�CE&\(8-0/�7E+IR�&8CE&)R�X$:6HI-0/$?�A�+.*E9Z*,9$&\(8-07b*,7<-6^W-¤J�&8C�CES$/$7)X�R$&8HI:�U'7"+I/2R�&8HI+5J0&)C�U0X�:�/$R27�S$P$7�&8x]S$&8/c*MN:�+I/c*,&)/�:�/$()&�3

� S$R$+.(8+.-0S$7�S�7E&�-�^¡^{-0C�MZ:�HTMG&)*,9�-'R$7�(�:�/q9�:�J0&�:LJ�&8CbU�9$+I?�9@F�:�U0-�`YXcF�:�Cb*,+.(8S$HI:�CEH5UO+./@CE&)x]S$+IC�&8MG&8/c*,7)X7EFQ&8()+���(8:6*,+.-0/$7)XW:�HI?0-�CE+.*E9$MG78Xa:�/$R�F$C�-0?0C,:6MN7 ()-0/$()&8CE/�&8R A�+5*,9�&)7EFQ&8(8+I:�HIH5Uu(8CE+5*,+.(�:�H#^{S$/$()*E+I-0/$:�HI+5*BU �7ES�(g9�:�7Z(8-0/$()S$CEC�&8/$(>U0X 7bUT/$(g9$CE-�/$+I[8:6*,+.-0/�X\:KJ�-0+IR$:�/$(8&�-6^OR�&�:�R$H.-'(gD]7�:�/�RrC,:�()&�(8-0/$R�+.*,+.-0/$7N+I/�*,9�&7EMN:�H.H�X�:�/$R FQ&8CE9$:�F$7u&)J0&)/�/$&>*BA�-�CEDr7�*,:�P$+.HI+.*BU§:�/�Rz7�S$C�JT+.J6:�P�+IHI+5*BU�+./ :�H�:�C�?0&8Cv()-0/c*,&>=T*8X R$&8C�+.J�&8R-0/�*E9$&�P�:�7�+I72-�^�MG-0CE&�R$&)*,:�+IH.&8Rr:�/$:�H.UT7E&)7v-�^�(8-0MGFQ-0/$&8/c*E783 i�9�&8CE&�+.72/$-�7�S$P$7�*E+.*ES�*,&�^{-0CZS$7E+./$?R$&)MN-0/�7�*,CE:�P$H5U27E-�S$/$R�:6HI?0-0C�+.*E9$MN7L|ª&63�?�3.X ����1 � �~>3nBMGFa-0Cb*g:�/c*L&�:�C�H.UuA�-0C�D�-0/�*E9$&@&>`«&)()*,7f-�^�()-0MGFa-07�+.*E+I-0/sS$7E+./$?v9$+I&)C,:�C�(g9$+I(8:�HIH5U�H�:�U0&)CE&)R :6P$7�*EC,:�(��

*,+.-0/$7qA<:672F�:�Cb*2-�^�%'y�n ��7vV\+.&8CE:�CE(g9$+.(�:�H � &>J0&8H.-0F$MG&8/c*�©u&)*,9�-'R$-�HI-0?�U &>`«-�C�*p|{7E&)&�y�-�P$+I/$7�-0/�:6/$R¬�&)JT+.*�* ���c�0� t~�3�e�-0CL7�-0MN&OCE&8:�7E-0/«X«*,9$+.7\A"-0CEDu+I7\7�*E+IHIHWC�&8H�:;*,+.J�&8H5U�S$/$D]/$-KA�/�XW:�H5*,9$-0S�?09�+5* +I7�JT+.*g:6HW*E-^{-0C�MZ:�HaCE&8:�7E-0/�+I/$?G:�PQ-0S�*�7�S$P$7�UT7b*,&8M (8-�MNFQ-07E+5*,+.-0/v:�/$Rs:�/�:6H.UT7E+.7�-�^�&)MN&)CE?0&)/c*\F�CE-0FQ&8Cb*,+I&)783¥L^�F�:�Cb*,+I()S$H�:6C_+IMGFQ-0C�*,:�/$(8&N+I7_*E9$&Z^{-0C�MZ:6H�:�/$:�H.UT7E+.7@-�^�CE&)x]S$+IC�&8MG&8/c*,7 � ^{-�C@&>=�:�MGF$HI&6XdR$&)*E&8C��

MG+I/$+./$?_A�9$&>*,9$&)C\:�?0+5J0&)/s7�&)*�-�^#CE&)xTS�+ICE&)MN&)/c*,7�:6*�:�F�:�Cb*,+I()S$H�:6C<H�:�U0&)C�-�^�:�P$7�*EC,:�(>*,+.-0/v+I7�()-0/$7E+.7�*E&8/c*A�+.*E9$+I/N+.*E7E&8H5^�XTA�9�&)*,9�&8C<*,9�& R$+.`a&8C�&8/c*�7�&)*,7�-6^WCE&8x]S$+.CE&)MN&)/]*E7�:6*"*,9$& H.-KA�&)C<H�:�U0&)C�:�C�&\^{S$/$R$:�MN&)/c*g:�H.H.U+I/�(8-0MGF�:6*E+IP$H.&�A�+.*E9N-0/�&L:�/�-�*,9$&)C8XT:�/$RGA�9$&)*E9$&8C�*,9$&�C�&8x]S$+IC�&8MG&8/c*,7�:6*":�H.-KA�&)C"HI:KU�&8C�:�C�&\()-0/$7E+.7�*E&8/c*A�+.*E9Z*,9�&LCE&)x]S$+IC�&8MG&8/c*,7�:;*�*,9�&LS$F$FQ&8C�H�:�U0&)C83�¥ /$(8&\7ES$(g9u:�/2:�/�:�H5U'7�+I7�+I7"R$-0/$&6X'*,9�&8/2+5*�+.7<:�H.7E-_PQ&8/T�& �$(8+�:6H#*E-2R$&)*E&8C�MN+./$&OA�9$&>*,9$&)C 7�UT7b*,&8M 7EFQ&8(8+���(�:;*,+I-�/$7 :�/�R�+IMGF$HI&)MN&)/c*g:6*E+I-0/$7�:�C�&_()-0/$7E+.7�*E&8/c* A�+.*E9*,9�&�CE&)HI&>J�:6/]*ZCE&)xTS�+ICE&)MN&)/c*,783 |}e�-0C�MZ:6H�:�/�:�H5U'7�+I7N:�F$F$H.+I&)R *E-7,:6^{&>*BU CE&8x]S$+.CE&)MN&)/]*E72+I7G(8-�/$7E+.R$&8C�&8R+I/ � 4¤��� �3�~n�*vM@S�7�*vPQ&�&8MGF$9�:67E+I[)&8R�*E9�:6*2*E9$&�MG-07�*NJ�:6HIS�:�P�HI&�S�7E&87v-6^�^{-�CEMN:�H�MN&>*,9$-TR$7v:�C�&�+I/ ��/$R$+./$?

�¡:�A�7�:�/�R�+I/$()-0/$7�+I7�*E&8/$()+I&)78X«/�-�* +./�:6*E*E&8MGF�*,+./$?q*,-2F$C�-KJ0&_*E9�:6* 7�-0MG&)*,9�+I/$?N+I7�(8-0MGF$HI&>*,&)H.U�(8-�CECE&)()*83V\-KA"&)J�&8C8X�^{-0C�MZ:6H�MN&>*,9$-TR$7N:�F$F$C�-c:�(g9$&)72:�C�&s/$-6*2:�P�7E-0H.S�*,&�?0S�:6C,:�/c*,&)&87)X�Pa&)(�:�S$7�&�F$C�-0P$H.&8MG7N(8:�/&>='+.7�*�-0S�*E7E+.R$& -�^W*,9�&8+IC�7E(8-�Fa&�-�^Y:�/$:�H.UT7E+.783de�-0C�&>=�:�MGF$HI&6X�7ES�F$Fa-�7E&�*,9�:;*�:@?0+.J�&8/u:�/�:6H.UT7E+.7�R$-T&87�/$-6*R$&>*,&8(>*@:6/]U �¡:�A�7O-0C�+./$(8-�/$7E+.7�*,&)/$(8+.&87�+I/p:�7EFQ&8()+���(8:6*,+.-0/p-0C�+IMGF$HI&)MN&)/c*g:6*E+I-0/�3On�*�+I7�7�*E+IH.H Fa-�7E7E+.P$HI&*,9$:6*"*E9$&�CE&8x]S$+.CE&)MN&)/]*E7<:�C�&\+./�:�R$&)x]S�:6*,&_|ª&63�?�3.X]*,9$&�7EFQ&8()+���(8:6*,+.-0/$7�(8-0S�HIRq^ª:�+IH$*E-_F$C�&)J0&)/c*�:�F�CE-0P$H.&8M/$-�*�()-KJ0&8C�&8RsP]UZ*,9$&fCE&)x]S$+IC�&8MG&8/c*,7,~>X�-0C<*E9�:6*�*,9�&f:�/�:�H5U'7�+I7�MG&)*E9$-'R�7<*,9$&)MN7�&8H.J�&87�(8-�S$HIR�PQ& �¡:�A�&)R�3e�-0CW*,9$&)7E&<C�&�:�7�-0/$78Xc&�=T*,&8/�7E+.J�&<*,&)7�*,+./$?L-6^¡R$&)J�&8HI-�Fa&)R�7�UT7�*E&8MG7 +I7Y:�HI7�-L+.MNFQ-0C�*,:�/c* O:�HIPQ&8+5*#+I/$9$&)CE&)/]*EH.UHI+.MN+5*,&)R�3�\/'^{-0C�*ES$/�:6*E&8H.U�X�*,&)7�*,+./$?�+I7 +5*,7�&8H.^�+./$9$&8C�&8/c*,H5U�+./$(8-0MGF$H.&)*,&@:�/$Rj+I/$(8:�F�:�P$H.&@-�^�R$+.7E(8-KJ�&8CE+./$?uMZ:�/cU

*BUTFa&)7�-�^�F$CE-�P$HI&)MN7 � ^{-0CW&>=�:�MGF$HI&6X67b*,&)MNMG+I/$?�^{C�-0M¨R$+.7�*,C�+IP$S'*,&8R�7�UT7b*,&8M¦+I/c*E&8C,:6()*,+.-0/$7#:�/$RO(8-0/�(8S$C��CE&)/$()Us^ª:�+IH.S$CE&)78XQ7ES$P'*,HI&�*,+.MN+./$?NF�CE-0P$H.&8MG78XaS$/�:�/c*,+.(8+.F�:6*,&)R�9�:�C�R�A�:�CE&_^ª:6+IHIS�CE&87)X«:6/$R�&8/cJT+IC�-0/$MG&8/c*g:�H&)`a&8(>*,7)3 � ='9�:�S$7b*,+5J0&f*,&87b*,+./$?q-¤J�&8C\:�HIHaFa-�7E7E+.P$HI&�7�(8&)/�:�CE+.-07�+I7�P�:67E+I(8:�HIH5UG+IMGFa-07�7E+.P$HI& +./�:�/cUv(8-�MNF$H.&>=7�UT7b*,&8Mu3k�-0/$7�+IR$&)CE+./$?u*E9�:6*O7ES$CbJT+.J6:�P$+.HI+.*BU�XW7E&8()S$CE+5*BU0XYCE&8H.+�:�P�+IHI+5*BU0X�:6/$Rh^ª:�S$H5*�*,-0H.&8CE:�/$(8&N:�C�&Z:�H.H A�&8:�D0�BH.+I/$D

F$C�-0Fa&)C�*E+I&87)X'^{-0C�MZ:6HaMG&)*E9$-'R�7<:�/$Rv/�-0/�^{-0C�MZ:�H¡*,&)7�*E+I/$?q:�C�& PQ-�*,92S�7E&)^{S�H�:�F$F$C�-c:�(g9$&)7�+I/�:6*�*,&)MNF�*E+I/$?*,- ��/$Ru*,9$&fA�&8:�D�HI+./$D]783� �&8+.*E9$&8C�+I7�:�R�&8x]S�:6*E&_PcUu+.*,7�&8H5^�3 � /s+I/c*,&)CE&)7�*,+./$?G/$-0/�^{-0C�MZ:6HW:�F$F$C�-c:�(g9s*E-^ª:�S$H5*f+I/���&)()*E+I-0/�*,-�R$&>*,&)()*�^ª:�+IH.S$CE&�MG-'R�&87�+I7f?0+5J0&)/ PcU��-c:�7�:�/�R©s( �fCE:�A � ��£c� ���7�+IMG+IH�:6C :�Rj9$-T(:�F$F�CE-c:�(g9�&87�:�C�&<(8-0MGMG-0/_A�+.*E9@CE&)7EFQ&8(>*�*E- CE&)R'��*E&�:�M :6*�*g:�(gD]7d+I/O*,&87b*,+./$? A�-�S$HIR'��Pa&�7E&8()S$CE&�7bUT7�*,&)MN7)3e�-0CEMN:�H]MG&)*,9�-'R$7�9�:�J0&�PQ&8&8/qS$7�&8Rq&>=T*E&8/$7�+.J0&)H.U�+./_*,9�&�F�:�7�*�^{-0C�7�&8(8S�CE+.*BUv|ª&63�?$35X����0�'Xc��¢'X'4�101$X'4¤�0�TX

4¤���TXc� �T4�Xc�6�0¢'X0�0���'X �0�0¢TX � �'4��X6^ª:�S$H.*#*,-�HI&8CE:�/$()&�|ª&63�?�3.X ���c�TX'4 �'40X'4�� ��XT4K£0�'X0���0�TXc�0�0�]Xc�0�6£'Xc���61�X0��¢ ���~>X?0&)/$&8CE:�H�(8-0/$7�+I7b*,&8/�()U � 4���4 }X<-0P���&)()*b�B-0C�+I&8/c*E&8R�F�CE-0?0CE:�MG7u|ª&�3�?$35X ��1��~>X"(8-0MGFQ-07,:�P�+IHI+5*BUr|ª:�7G/$-�*,&)R�+./%'&)()*,+.-0/ �'3�£c~�Xa()-0MNF�+IHI&)C\()-0CEC�&8(>*,/$&)7E7G|ª&63�?�3.X � ���0£ �~>XQF$CE-�*E-'()-0H#R$&)J�&8HI-�F$MN&)/c*G|ª&63�?$35X � 4 �0�'XY4 �61�X � ��£��~>X9�:�C�R�A�:�CE&�J0&)CE+���(�:6*E+I-0/p:6/$Rp(8-0MGF$S�*E&8Cb�B:�+IR�&8R�R$&)7E+I?�/ ���0� � �XW:6/$Rp9TS�MZ:�/p7E:6^{&)*BU |{&�3�?$35X � 4K����X ��1�4 �~

���

Page 98: Practical Architectures for Survivable Systems and Networks (Phase

P$S�*�*,-u-0S$C�D]/$-KA�HI&)R$?0&G/$-�*�^{-0Cf7ES$CbJ'+5J6:�P$+IH.+.*BU�X�-0C�^{-0Cf7E&8()S$CE+5*BU :�/$R ^ª:6S$H.*�*E-0HI&)C,:�/$()&N+./ ()-0M@P$+./�:;�*,+.-0/�3N¥ /$&q7E&)CE+I-�S$7�:6*E*E&8MGF�*O:6*O:�P�CE-c:�R�&8C�:�F$F$C�-c:�(g9 (8-0MG&87�^{CE-�M *,9$& � S$C�-0Fa&8:�/hR�&8FQ&8/$R�:6P$+IH.+.*BU(8-�MNM@S�/$+.*BU�XQA�9$+.(g9�*,&)/$R$7L*E-2(8-�/$7E+.R$&8C\R$&8FQ&8/$R$:�P$+IH.+.*BUu:�7L:�/�:�H.H5��&8M@P$CE:�(8+./$?�x]S�:�H.+.*BU |}:67L/$-�*E&8R�+./%'&)()*,+.-0/ 403��T3 �c~�3 � C�&8F$C�&87E&)/c*g:6*E+.J0&Z&>=�:�MGF$HI&�-�^"*,9�:;*_:6F$F$CE-0:�(g9h+.7f^{-�S$/$Rj+I/p*,9$&�A"-0CED�-�^ �f&)C,:�C�R¬�&�¬W:�/$/ � 4¤���'Xa4¤�T4 �C�&8HI:6*,+./$?�*E- � � �B(8C�+.*E+I(�:6Ha:6F$F$HI+.(�:6*E+I-0/�7��$X0A�9$&)CE& � (8-0S$H.R2PQ&�:�/cUZx]S�:6HI+��$&8C�7ES$(g9:�7 � � �� � ���� � ��� ���� ��� � � �� ��� � � �� �� ������a-0C ����������:6H.*,9�-0S$?09v9$+.7<^{-0CEMN:�HaMN&>*,9$-TR$7�9�:�J0&�*E9TS�7�^ª:6CPQ&8&8/j:�F�F$HI+.&8R�F�CE+IMN:�C�+IH.UZ*,-2^ª:�S$H5*\*E-0HI&)C,:�/�(8&�3�%T&8&@*,9�&@R$+I7�(8S$7�7E+.-0/p-�^d*,9$&_CE-0H.&_-�^�^{-0C�MZ:�HWMG&)*E9$-'R�7+I/�7�&8(8S�CE&�7�UT7�*E&8M :�CE(g9�+.*,&)()*ES$CE&)7�PcUu �&8S$MN:�/$/ ��� �'4�}3i�9$&_A"-0C�D�-�^ � -0/j©u+IHIH.&8/uS$/$R$&)C *,9$&_F$CE-���&)()*�+.7 7ES�MNMN:�CE+.[8&)R�+I/ � F$FQ&8/$R�+5=�L3 � +5*,9�F�:6C�*,+.(8S'�

H�:6C<CE&)HI&)J6:�/�(8&f*,-�*,9$&�^{-0C�MZ:6HI+I[8:6*,+.-0/Z-6^�7�S$C�JT+.J6:�P�+IHI+5*BU0X'9$&f9�:�7�?0&8/�&8C,:6HI+I[)&8R�&�:6CEHI+.&8C�7�&8(8S�CE+.*BUc��CE&8HI:6*,&)RA"-0CEDf-�^ak<:6*E9$&8C�+I/$&�©s&8:�R$-KA�7����6� ��T*,-L:�R$R$C�&87E7Y*,9$&"(8-0/��$?0S$C,:6P$+IH.+.*BU�-�^$7ES$CbJ'+5J6:�P$HI&�7E&)C�JT+I()&87)3 � :�CEH.+I&8CCE&)7ES$H5*,7"-�^�9$+.7"7�S$C�JT+.J6:�P�+IHI+5*BU@A"-0CEDG:�C�&L?0+5J0&8/N+I/Z:OF$S$P�HI+I7�9$&8RZCE&87�&�:�C�(g9vF�:�FQ&8C ���T4�1�¡*,9�:;*<(g9�:�CE:�()*E&8C��+I[)&87"CE&8()-0/���?�S$C,:6*E+I-0/2:�7<:_D]+./$RZ-�^ �$-¤AwF$C�-0FQ&8C�*BUq*E9�:6*<(8:�/2PQ&L^{-0C�MZ:�H.H.U_7,:6*E+I7 �$&8R�3�©s+.HIH.&8/���7"C�&8()&8/c*7ES�C�JT+.J6:�P$+.HI+5*BU_MG&�:�7�S$CE&<A"-0C�D ���'4���¡&>=T*E&8/$R$7�*,9�&�7bUT7�*,&)M MN-TR$&)H$+I/c*,C�-'R�S$(8&)RN+./q*E9$&�CE&)(8-0/��$?0S$C,:;*,+I-�/F�:�FQ&8C ���'4�1��*E-G:G7b*,CES�()*,S�C,:�HW9$+.&8C,:6CE(g9cU03�k�-0MGFa-0/�&8/c*,7�-�^ 7bUT7�*,&)M 7E&8CbJT+I(8&)7L:6CE&�JT+I&)A"&8R�:�7�7E&)C�JT+I()&87A�+.*E9�()-0MNFQ-0/$&)/c*,7L-6^ *,9$&)+IC�-KA�/�3 � +.*,9u*,9$+.7L:6R$R$+.*E+I-0/$:�H�R$+IMG&8/�7E+I-�/�X�-0/$&O(�:�/�R�& ��/$&OR$&8FQ&8/�R$&8/$(>U-�^�:u7E&)C�JT+I()&2-0/:uHI-KA"&8Cb��HI&>J0&8H�7E&)C�JT+I()&�X�:�/�RhHI-T-0D�^{-0C�:�HI:6*E*E+I()&>��J6:�H.S$&8RpMG&�:�7�S$CE&N-�^�7�S$C�JT+.J6:�P�+IHI+5*BU^{-0C ()-0MGF�:�CE+./$?Z7�&8CbJ'+.(8&)7f*E9�:6*�MN:�U�PQ&�:6*�R�+.`a&8CE&)/c*fHI&)J�&8H.783�i�9$&�(8-0/�(8&8F'*,7f+I/�*E9$&�MG&�:�7�S$CE&�F�:6Fa&)C9�:�J0&OPa&)&8/�7�+IMGF$HI+���&8R�R$CE:�MN:6*,+.(�:�H.H.U0X]U0&>* 7b*,+IH.H�HI&8:�Ru*E-Z:GMZ:¤=T��MN+./2^{-0CEM_S$H�:@^{-0C�*,9$&�MG&�:�7�S$CE&f*,9�:;*7,:;*,+I7 ��&87�*,9�&O+./]*ES$+.*E+.J�&8H.UN/$&)(8&87�7,:�CbU�F�CE-0FQ&8Cb*,+I&)783�i�9$&fA�-0C�Du:�HI7�-G()-0/$7�+IR$&)CE7�S$/$+Ix]S$&)/$&87�7LF$C�-0FQ&8C�*E+I&)7^{-0C<*E9$&OMG&�:67ES$C�&O:6/$Rs-6*,9$&)C�F�CE-0FQ&8Cb*,+I&)7�-�^Y*E9$&�9$+I&)C,:�C�(g9$+I(8:�H�7�*ECES$(>*,S$C�&�X¡7ES�(g9�:�7�(8C�+.*,+.(�:�H.+.*BUG-�^�7E&)*E7-�^Y(8-0MGFQ-0/$&8/c*E783¥L*,9$&)C�F�:�FQ&8C�7qA"&8C�&u:�HI7�-�R$-0/$&�PcU ©s+.HIHI&)/A�+.*E9 :6*qHI&8:�7�*qF�:6C�*,+I:�H � y\¬w7ES$F�Fa-0Cb*�X�CE&)H�:6*E+I/$?�*E-

(8&)C�*E+���(8:6*,&�C�&)J0-T(�:;*,+I-�/ ���'4�40X��'4K��d:�/�RjC�&�:�7�-0/$+./$?�:�PQ-0S�*fF$S$P�HI+I(��BD6&)Us+I/�^{CE:�7�*ECES$(>*,S$C�&87 ���T4K£�}3v| � -0/©s+.HIHI&)/ +I7G:�HI7�-jA"-0C�DT+./$?jS$/$R$&)C2: � � y\l � ()-0/c*,C,:6()*G*,-p^{-0CEMN:�HIH5UhMG-TR$&8H�:�/�R�F$C�-¤J�&�F$C�-0FQ&8C�*E+I&)7-�^"/$&)*BA"-0C�D�F$CE-�*E-'()-0HI7 :�/$Rj(8C�UTF�*E-0?0CE:�F$9$+.(�F$CE-�*E-'()-0HI7)X�S$7E+./$?s%�y�n ��7�l �f%�J0&)CE+��$(�:6*E+I-0/p7�UT7b*,&8M ^{-�C^{-0C�MZ:�HaF$CE-T-�^{7 29c*E*,F«��m0m¤A�A�Af3�()7EH�3�7EC�+�3�(8-0MZm6FcJT783�9c*,MGH�3�~e�-0CEMN:�HWMG&)*,9�-'R$7 :�CE&_:�HI7�-Z*,9$&�P$:�7E+.7L^{-0CLMG&)*E9$-TR$7L^{-0C\Pa&)HI+I&>^�HI-0?�+I(87�*,9$:6*�FQ&8CEMG+.*�*,9�&@7�UT7�*E&8M��

:6*E+I(�:�/$:�H.UT7E+.7�-�^Y(8C�UTF�*E-0?0CE:�F$9$+.(�F$CE-�*E-'()-0HI7)X$7�*E&8MGMN+./$?@^{CE-�M *,9�& �S$CEC�-KA�7b� � P�:�R$+ �� �&8&8R�9�:�M �  HI-�?0+I( ���0� }X0:�7#A�&)HIH$:67�MG-0CE&�CE&)(8&8/c* A"-0C�DOPcU��f-0/�?$X0 �&8&8R�9�:�M :�/$R �":�9$:�HI-0M � 404 � �Xc©s&�:�R�-¤A�7 �����61��X�f:�+IHI:�C�:�/�R��HI+I?�-0C � 4�1c��}X � H5J0&87���e�-07�7 ��¢ �X � P�:�R$+#:�/$R �f-�CER$-0/ �����XQ:�/�R�-�*E9$&8C�783<i�9$&)CE&O+I7�(8-0/�7E+IRT�&8CE:�P$H.&Z-�*E9$&8C�A�-0C�D -�/h^{-0CEMN:�H�:�/�:6H.UT7E+.7O-�^�()C�UTF�*E-0?0C,:6F$9$+I(NF$CE-6*,-T(8-0H.78X�+./$(8H.S$R$+./$?�©s&8:�R$-KA�7 ������1�-0/vD6&)U2MN:�/�:6?0&8MG&8/c*�X'¬�-KA�& � 4K£�1��-0/� �&8&8R�9�:�M��b%'(g9$C�-'&)R$&8C)X�:�/$R�lY:�S$H.7E-0/ ����¢�46X���¢c� �X$©s+.*E(g9$&8H.H«&>*:�H}3 ���0�6� �Xa:�/$R�¬W+./$(8-�HI/u&)*�:6H�3 � 4¤�0� Y-0/s(8C�UTF�*E-0?0CE:�F$9$+.(@:�/$R�:�S�*,9�&8/c*,+.(�:6*E+I-0/uF$CE-6*,-T(8-0H.7\+./s?0&)/$&8CE:�H�3%'&)&�:�HI7�- � P�:�R�+$:�/$RG �&8&8R�9�:�M ��7 ^{-0C�M@S$HI:6*,+.-0/_-�^QF$C�S$R$&)/]*�&)/$?0+./$&8&)CE+I/�?�F$C,:�(>*,+.(8&�^{-0C�(8C�UTF�*E-0?0CE:�F$9$+.(F$C�-�*,-T(8-0H.7 � ��}3L%'&8&_:�HI7�-v©s+.HIHI&)/u:�/$R�y�S$&87�7 ���'4¤� #^{-0C\:N7�&8F�:�CE:6*,+.-0/�-6^dF$CE-6*,-T(8-0H �B+I/�R$&8FQ&8/$R�&8/c* :6/$RF$C�-�*,-T(8-0H �BR$&)Fa&)/$R$&)/]*\:�/$:�H.UT7E&)7O|ªFQ&8C�^{-�CEMG&8R�S$/$R$&)C � � y\l � ()-0/c*,CE:�()*g~>3�&)HIHI-KJT+I/ ���c��W7�9$-KA�7\9�-¤A�^{-0CEMN:�HaJ�&8C�+���(8:6*,+.-0/s(8:�/uPa&fS$7�&8R�*E-G()-0/$7b*,C,:6+I/�*,9$&f(8-TR$&�?0&8/�&8C,:;*,+I-�/

F$C�-'()&87E7)X�A�9$+.(g9_(�:6/_PQ&"F�:6C�*,+.(8S$HI:�CEH5U +.MNFQ-0C�*,:�/c*W+I/�7E-0S�CE(8&���:�J6:�+IHI:�P$H.&d(8-0MGF$+IH.&8C�78XKA�9$&8C�&�()-0/$7E+.7�*E&8/$(>UPQ&)*BA"&8&8/*E9$&G7E&8MN:�/c*,+.(87�-�^�*E9$&G7E-0S$C�(8&N(8-TR$&Z:6/$R *E9$&N7�&8MN:�/c*,+.(87�-�^�*E9$&N-�P���&8(>*@(8-TR$&G+I7f(8C�+.*E+I(�:6H�X+I/�R$&8FQ&8/$R�&8/c*L-6^Y*E9$&f(8-0MGF$+IH.&8C)3%'&)&\:6HI7E-� �� �� ��� � � �� ���� ��� ��� � � � ��� ��� � �� � � � ��������� �� ����P]U � -0/�:6*E9�:�/ �-KA�&)/2:�/$RN©s+.(g9�:�&)H

V\+./$(g9$&>U ����4 �X$A�9�+I(g9s:�F$F$H.+I&87<^{-�CEMN:�H«MG&)*E9$-'R�7<*,-G+I/c*,&)?0CE+5*BU03e�-0CEMN:�H'MN&>*,9$-TR$7�(�:�/N:�H.7E-�Pa&�S$7�&8RZ+./N&�='&8(8S'*,+I-�/�X�:67�+./qF$CE-T-�^��B(8:�CECbUT+I/$?f(8-TR$&�*,9$:6*�(�:�/GPa&�S$7�&8R

���

Page 99: Practical Architectures for Survivable Systems and Networks (Phase

*,-Z&8/$7�S$CE&@*E9�:6*�:N(8CE+5*,+.(�:�HW(8-�MNFQ-0/$&)/]* 9�:�7L/�-�*�PQ&8&8/�*,:�MGFa&)CE&8RsA�+.*,9«3 e�-0CL&�=�:�MNF�HI&�Xa7E&)& �f&)-0CE?�& \&)(8S$HI: ��7O*,9�&87E+.7OA"-0CED ��� � ���:�/$R � &)P7E+5*,&�|ª9c*E*EF���m�m;A�A�Af3�()783�Pa&)CED6&8HI&>U03�&8R$S�m � /$&)(8S$HI:cm0~>X�+I/�(8HIS�R$+I/$?:s9$:�/$R$7��B-0/ R$&8MG-0/$7b*,C,:;*,+I-�/�3p| � /&�:6CEHI+.&8C�-0/�&>�BF$:�?0&G7ES$MGMZ:6C�Up-�^< \&8()S$H�: ��7�A�-0C�Dp+I/jF$CE-0?�CE&87�7_+.7?0+5J0&8/u+I/ ��� �0� �3�~¥L^WF�:�Cb*,+I()S$H�:6C"+./]*E&8C�&87�*�+./Z*,9�& (8-0/c*E&>=T*�-�^#9$+I?�9$H.Uq7�S$C�JT+.J6:�P�HI& 7bU'7b*,&)MN7)X$^{-0CEMN:�H¡MN&>*,9$-TR$7<9$:KJ�&f:

FQ-�*,&)/]*E+�:�H.H.UqJT+.*,:�H�CE-�HI&�+I/�C�-0P$S$7b*\7�-0S$C�(8&>�B:�J�:6+IH�:6P$HI& 7�-�^t*BA�:�CE&6X�(8-0/$7�+IR$&)CE&)R�+I/s%'&)()*E+I-0/ �'354K��3i�9$&Z%�y�nfk�-0MGF$S�*,&)CO%'(8+.&8/$()&2¬W:�PQ-0C,:6*E-0C�Us^{-0CEMN:�H MG&)*E9$-TR$7 � &8P 7E+5*,&q9�:�7O:�7E7�&8M@P�HI&8Rh:�/h&�=]�

*,&)/$7E+5J0&�()-0HIH.&8()*E+I-0/s-�^ �Ly�¬�7G|ª7�&8&�9c*E*EF���m�m;A�A�Af3�()7EH}3�7�CE+�3�(8-�M2m6FcJT783�9c*,MGHt~\C�&8F$C�&87�&8/c*,+./$?vA�-0C�DsA�+5*,9$+./k�%�¬:6/$Rs&)HI7�&)A�9$&)CE&�+I/v*,9$&�A"-0CEH.R�-0/v^{-0CEMN:�H�MG&)*E9$-'R�783

������� � Y��d�����r � � �T�� �_�#�� � �� � �g����d���

� &j/�&>=T*u(8-0/$7�+IR$&)Cu: (g9�:6HIHI&)/$?0+./$?�:�H5*,&8C�/�:6*E+.J0&�*E- (8-0/cJ0&)/c*,+I-�/�:�Hf7E-�^t*BA�:�C�&jR�&)J0&)HI-0F�MN&)/]*83�� ¥�S�CS$H5*,+IMN:6*E&d?0-c:�Hc9$&)CE&"+I7�*,-\Pa&":�P$H.&�*E-LR$&>J0&)HI-0FOCE-0P$S�7�* 7bUT7�*,&)MN7�:�/$R_:�F$F$H.+I(�:;*,+I-�/$7�*,9�:;* :�C�&"(8:�F�:�P�HI&�-�^7,:;*,+I7b^tUT+I/$?\7E&8C�+I-0S�7�CE&)x]S$+IC�&8MG&8/c*,7)X0/$-�*�MN&)CE&8H5U�^{-0C�7�&8()S$CE+5*BUOP�S�*�:�H.7E-�^{-0C�C�&8HI+I:�P$+.HI+.*BU�X�^ª:�S$H5*#*E-0HI&)C,:�/�(8&�X9]S$MN:�/_7E:6^{&)*BU�Xc:�/$RO7ES$CbJ'+5J6:�P$+IH.+.*BUL+I/f*,9$&�^ª:�(8&�-�^$*E9$&�A�+IR$&�C,:�/�?0&"-6^�CE&8:�HI+.7�*,+.(�:�R�J�&8CE7�+.*E+I&87#(8-�/$7E+.R$&8C�&8R+I/@*E9$+I7dC�&8FQ-0C�*83 � H.7E-�C�&8HI&>J6:�/c*�:�CE&�:�R�R$+.*E+I-0/�:6H�-0FQ&8CE:6*,+.-0/�:�HTCE&)xTS�+ICE&)MN&)/c*,7�7ES$(g9Z:�7d+I/c*E&8CE-�Fa&)C,:�P$+.HI+5*BU0X&)J�-0H.J6:�P�+IHI+5*BU2:6/$R�MZ:�+./c*g:�+./�:�P$+.HI+.*BU�X]:�7�A�&)HIHW:�7�R$+.7E()+IF$H.+I/$&\+I/v*,9$&f7�-�^t*BA<:6CE&�R$&)J�&8HI-�F$MN&)/c*\F�CE-T(8&87�783� &87�F$+.*E&�:�H.H$-0S$C F$:�7�*�CE&)7E&8:�CE(g9�XTR$&>J0&8H.-0F$MG&8/c*�-�^Q(8-0MGMG&8CE()+�:�H'7�UT7�*E&8MG7�+I7dR$&)(8+IR�&8R$H5U@7ES�Pa-0F'*,+IMN:�H

A�+.*E9�CE&87�Fa&)()*�*,-qMG&8&)*E+I/$?q7b*,CE+./$?0&)/]*�C�&8x]S$+.CE&8MG&8/c*E783i#-�PQ&dF$C�&8(8+.7E&�:�PQ-0S�*W-0S�C�*,&8C�MN+./$-0H.-0?�U0X)A�&�R$+.7�*,+./$?0S$+.7E9�9$&)CE&�PQ&)*BA"&8&8/ ��� � ��� � ����|{*E9�:6*W+I7)X¤(8HI-�7E&8RT�

PQ-K=�-0C�(8H.-07E&)R'�B7�-0S$CE()&K~\7�-�^t*BA�:�CE&�+./sA�9$+.(g9�7E-0S$C�(8&@()-'R�&@+I7�/$-�* :KJ6:�+.H�:�P�HI&�XQ:�/�R ��� ��� � ���_7E-6^t*BA<:�C�&|ª-T(8(8:�7E+.-0/�:�H.H.U�(8:�HIH.&8R � � � �� � ���¤~�+I/�A�9$+I(g9�7�-0S$C�(8&<()-'R$&"+I7�:KJ6:�+.H�:�P�HI&�|}:6H.*,9�-0S$?09OFa-07�7E+.P$H.U�-0/$H5UfS$/$R$&)C(8&)C�*,:�+I/�7�Fa&)(8+���&8Rr()-0/$R$+5*,+I-�/$7g~�3 �HI:�(gD0�BPQ-K=§7�-�^t*BA<:6CE&�+.7Z-�^t*E&8/r(8-�/$7E+.R$&8C�&8R :�7Z:�R�J6:�/c*g:�?�&8-0S$7ZP]UJ0&)/$R$-0C�7�:�/$RsPa&)HI+.&)J0&)CE7\+I/u7E&8()S$CE+5*BU�PcUu-0P$7�(8S$C�+.*BU�3\V�-KA�&>J0&8C)X�P$HI:�(gD0�BPQ-K=s7�-�^t*BA<:6CE&_MN:�D6&87L+5*�M@S$(g9MG-0CE&�R$+��G(8S$H5*�^{-0C�:�/cU0-0/$&G-�*E9$&8C�*,9$:�/j*E9$&q-0CE+.?0+I/$:�H�R$&>J0&)HI-0FQ&8C�7�*E-uR�+I7E()-KJ0&8C�JTS$HI/$&)C,:�P�+IHI+5*,+.&87 :6/$RF$C�-¤JT+.R$&���='&87d*E9$&8C�&)^{-0C)3d¥LJ0&)C,:�H.H�X0+5* (�:6/�Pa&�: 7�&8C�+I-0S$7�-0P$7�*,:�(8H.&�*,-�9$:KJT+./$?f:�/cU_S�/TP�+�:�7�&8Rq(8-0/ ��R$&8/�(8&+I/N*,9$&�:6P$+IH.+.*BUq-�^Y:_7bU'7b*,&)M�*,-@^{S$H���HIH¡+5*,7<C�&8x]S$+IC�&8MG&8/c*,7�|ª7E&)(8S$C�+.*BU�X$CE&)HI+�:6P$+IH.+.*BU0Xc7E:6^{&)*BU�X�:�/$Rv7�-�-0/�X�:67:�F$F�HI+I(8:�P$H.&K~>3

� &�:�H.7E-jR$+I7b*,+./$?0S$+.7E9 9$&8C�&�PQ&)*BA"&8&)/ ���������� �� � � �s:6/$R � � � ���������� ���� � �v7�-�^t*BA<:6CE&�3w �-�*,&�*,9�:;*-0FQ&8/'��Pa-�=�7�-�^t*BA�:�CE&f(�:6/s()-0MN&�+./vJ�:6CE+I-�S$7�F$CE-�F$CE+.&)*g:6C�Uv:6/$Rs/�-0/$F$C�-0F$CE+.&)*,:�C�U �¡:�J0-0C�783

����������� ���! #"%$'&��)(�*,+�( �.-0/ �%1

� &8FQ&8/�R$&8/$()&f-0/vP$H�:6(gDc��Pa-�=ZF$CE-�F$CE+.&)*g:6C�UG(8-TR$&�:�/�RvF$CE-0F�CE+I&>*g:�CbUZ+./c*,&8Cb^ª:�(8&)7<(�:6/u9$:KJ�&�MZ:6/]UNR$+.7,:�R'�J6:�/c*g:�?�&878�

2 ��/�:�J6:�+IHI:�P$+IH.+.*BUN-�^d7�-0S$CE()&@(8-TR$&@H.&�:�R�7�*E-2+I/$7�(8C�S�*g:�P�+IHI+5*BU0X�A�9$+.(g9�MN&8:�/$7�*,9�:6*\*,9$&O(8-TR$&@+.7\S$/T�:6/�:�H.UT[8:�P$HI&f+./�:�/cUuF$C,:6()*,+.(�:�HW7�&8/$7�&�X�F�:6C�*,+.(8S$HI:�CEH5U2PcUuD]/$-KA�HI&8R�?0&�:�P�HI&_()-0HIH.&�:�?�S$&87�A�9$-ZMG+I?�9]*�$/$Rs7�&8C�+I-0S$7���:KA�7)3

3!4�57698:8<;!=!><69?A@B69@C=!?AD<EF?ADHG.>H;!8:IJG.>H;!D<6KGMLONPDH?AIQGRE�GM@7;�LSE0?A8<6 >H69?A@TE�GME0;!D'UWVYXZ;![CIJGM@C@]\ ^A_A`.acbed�DH6 >f>H;!@YNP?AD#>H57;�gchihihkjlV�I�E0?A8H69[CIm?A@j�;!=![CDH6 >cVRGM@CnpoiDH6 qMGM=rVlbCstG�VR^AuAuAu7v

�%w

Page 100: Practical Architectures for Survivable Systems and Networks (Phase

2  �-0/$MG-'R�S$H�:�CL(8HI-�7E&8RT�B7E-�S$CE()&Z7�UT7b*,&8MG7@:6CE&G-�^t*,&)/ &)/$-0CEMG-0S$7)32i�9$&N+I/�:�P�+IHI+5*BUs*E-s7�S$P$7�&)*_*E9$&8M*BUTF$+.(�:�H.H.Uz9$+I/�R$&8C�7p*E9$& CE&)MN-KJ6:�H�-�^NS$/$/$&)(8&)7E7,:6C�U¦(8-0MGFQ-0/$&8/c*E78XG:�/$R�^{S$Cb*,9$&)Ch:�R�R$7�*,- +I/'�7�(8C�S�*g:�P�+IHI+5*BU03

2 k�H.-07E&)R'�B7�-0S$C�(8&@7bU'7b*,&)MN7�-�^t*E&8/�7�S�`«&)C ^{CE-0M :27�&8CE+.-0S$7 HI:�(gD�-�^�+I/c*,&)CE-0FQ&8CE:�P$+.HI+.*BUv:�/$R�(8-�MNFQ-07b�:6P$+IH.+.*BU0XdA�9$+.(g9�+./ *ES$CE/§(�:�/§CE&)7ES$H5*N+./§7bUT7�*,&)MN7GA�+.*E9§FQ-'-�C�7ES$CbJ'+5J6:�P$+IH.+.*BUr|}:�7qA�&)HIH�:�7GFQ-'-0C7E:6*,+.7�^ª:�(>*,+.-0/v-�^#*,9$&f7ES�P�*,&)/$R$&8RsCE&)xTS�+ICE&)MN&)/c*,7�� &87EFQ&8()+�:�H.H.UN7E&)(8S$C�+.*BUu:�/$RuCE&)HI+I:�P$+IH.+.*BU�~>3

2 k�H.-07E&)R'�B7�-0S$C�(8&f&8/cJT+IC�-0/$MG&8/c*,7�*,&)/$Rs*E-G+./$R$S$()&O7�+I/$?�HI&>��J0&)/$R$-0C�7�-0HIS�*E+I-0/�78X�A�9$+.(g9�+./�*ES$CE/�*,&)/$R*E-qF$CE&)(8HIS�R$&f(8-0/$7b*,C�S$()*E+.J0&�&)J�-0HIS'*,+I-�/�3

2 k�H.-07E&)R'�B7�-0S$C�(8&Z7bUT7�*,&)MN7O(�:�/�/$-�*@PQ&N:�R�:�F�*E&8RC�&�:�R�+IH.U�*,-�R�+.`a&8CE&)/c*_7�+.*,S$:6*,+.-0/$7f-0C�&�:�7�+IH.Uj:6/$Rx]S$+.(gD]H.UvC�&8F�:�+.CE&)R�A�9�&8/�7�&8C�+I-0S$7���:KA�7\:�C�&�R�+I7E()-KJ0&8C�&8R�3

2j� &)Fa&)/$R$&)/$(8&f-0/�F$C�-0F$CE+.&)*,:�C�UN+I/c*,&)C�^ª:�()&�7�*,:�/$R�:�C�R$7�?0CE&8:6*,H5UZ()-0MGF$HI+.(�:6*E&87<+./]*E&8?0CE:6*,+.-0/2-�^#HI:�CE?0&7bUT7�*,&)MN7f-0S'*f-�^�MN+ =T�B:�/$R'��MZ:;*,(g9�()-0MNFQ-0/$&)/c*,7�*,9�:;*�(8-0S�HIRp-�*,9�&8C�A�+.7E&�PQ&�A�&)HIH 7�S$+.*E&8R�*,-v*,9�&*,:�7ED]7�:6*�9�:6/$R�3

2 ldC�-0F$CE+.&)*,:�C�U�R�&)J0&)HI-0F�MN&)/]*Y-�^�P$H�:�(gD0��Pa-�=�7E-6^t*BA<:�C�&"9�+I/$R$&)CE7#-0FQ&8/@:6/�:�H.UT7�+I7�-�^'*,9$&�R$&)J�&8H.-0F$MG&8/c*F�CE-T(8&87�7�+.*,7�&8H5^�|tA�9$+I(g9u+I7�7�-0MN&>*,9$+./$?�MN:�/cUvR$&)J�&8H.-0Fa&)CE7\:�CE&�9$:�F$FcUv*,-q9$+.R$&K~�3

� +I/�R$-KA�7 �����0�_|ª  �'3��0~WC�&8FQ-0C�*E&8R$H5U A�+IH.Hc9�:�J0&�7�-0MG&)*,9�+I/$?�+I/�&>='(8&)7E7 -6^�����MN+.HIH.+I-0/ H.+I/$&)7W-�^$7�-0S$CE()&(8-TR$&u|{MN-07b* -�^�*E9�:6*f:�F�Fa&8:�CE7 *E-vPa&�D6&8CE/�&8Hd(8-TR$&�~>X«A�+5*,9p:�/$-6*,9$&)C��'3 �ZMG+IH.HI+.-0/�HI+I/�&87L-6^�:67E7E-T(8+I:6*,&)R*,&)7�*O(8-TR$&�3Gn�*�+I7�+.HIHIS�7�*,CE:6*,+5J0&@-6^�&8:�(g9h-�^"*,9$&)7E&q^ª:�()*E-0CE7)3��/�^{-0Cb*,S$/�:;*,&8H5U0X�*,9�&q*E-�*g:6HI+.*BUs-�^�(8-TR$&q-0/A�9$+.(g9�7ES$CbJT+.J6:�P$+.HI+.*BUv:�/$R�7�&8(8S�CE+.*BUsR$&)Fa&)/$R�+I7�&87�7E&8/c*E+�:�H.H.Uv*,9�&@D�&)CE/$&)H :�/$R�-0Fa&)C,:6*E+I/$?G7�UT7b*,&8M F$HIS�7FQ-�*,&)/]*E+�:�H.H.U2:�HIH«*E9$&O:�F$F$H.+I(�:;*,+I-�/v7E-�^t*BA�:�CE&�*,9�:;*L(8:�/�PQ&OH.-c:�R$&)R�:;*L:6/]Uv*E+IMG&�3"i�9�:6*\CE&8F�CE&87�&8/c*,7 :�/&8/�-0CEMG-0S$7":�MG-0S$/c*�-6^�(8-TR$&�*,9�:6*�M@S$7b*�PQ& ����� ��� �@|ªPQ&8(8:�S$7�& +.*�+I7�/$-�* ����� ����� ���������8~"+I/N:�/cUG(8CE+5*,+.(�:�H:�F$F�HI+I(8:6*,+.-0/�3w|ªy�&)(�:�H.H<*,9$&uR$+.JT+.R$&>��P]Uc��[8&8C�- +./�:6/� �i�:�F$F$H.+I(8:6*,+.-0/*,9�:;*NP�CE-0S$?�9]*q*E9$& ��-�CEDc*,-KA�/� &)?0+I7�MG+I7�7E+.HI& ()CES$+.7E&8C�*E-N:�9�:6H.*�X�+I/s%'&8(>*,+.-0/p403��'3�~%'F$+./$&8H.HI+.7����0��4 �()-0MGF�:�CE&)7L*,9�&@/]S$M@PQ&8CL-6^�7�UT7�*E&8M (8:�HIH.7\+./ � +I/�R$-KA�7f% � � |b4K¢�¢0£�X ��1]�0�q(�:�H.HI7g~

A�+.*E9�e�+.CE7b* � R$+5*,+.-0/ ��/$+5=h|�4K¢c�'4�X � �N(�:6HIHI7,~>XQ%'S�/¡¥f% �'3���|b4�¢0¢c�'XW4K¢0�G(�:�H.HI7,~>X¡:�/$R�¬W+./]S'=��'3���|b4�¢0¢0£�X�0��¢�(8:�HIH.7g~>3�i�9$&O()-0MGF�:�CE+.7E-0/v+.7�/$-�* �¡:;*E*,&)CE+./$?�*,-�*,9$& � +./$R$-KA�7\&)/cJ'+.CE-0/�MN&)/]*83� 9]S$MG-0CE-0S�7�P$S�*G7ES$P�HI+IMG+I/$:�HIH5U�7E&)CE+I-�S$7G:�7E7�&87E7�MN&)/c*Z-�^�*,9�&vS$7E&u-�^�(8-0MGMG&8CE()+�:�H"-�`¡��*,9�&>�B7�9$&8H5^

|�k�¥ i�%$~<7bU'7b*,&)MN7�+I7�?0+5J0&)/sPcU � :�JT+IRsk<:�CE/�&)U ���0¢ }3

����������� � �t1�� &��)(�*���+�( ��� " 1 &�� � �! ��p� 1� + ( � -F/ �%1

nB/2()-0/c*,C,:67�*�A�+5*,9NF$CE-0F�CE+I&>*g:�CbUqP$H�:6(gDc��Pa-�=N7E-6^t*BA<:�C�&L7bU'7b*,&)MN7)X�J6:�CE+.-0S$7�^{-0CEMG7�-�^�-0FQ&8/'��Pa-�=N7E-6^t*BA<:�C�&:�/$R�/$-0/$F$C�-0F$C�+I&)*,:�C�Uu7�-�^t*BA<:6CE&�-�`a&8C\-0F$FQ-0C�*ES$/$+.*E+I&)7�*E-27ES$C�MN-�S$/c* *,9$&)7E&@C�+I7�DT7L&8/]S$MG&8C,:;*,&8R�+./�*,9�&F$C�&)JT+I-0S�7�7�&8(>*,+I-�/�X�+I/vJ6:�CE+.-0S$7�A�:�UT783i�9$&�PQ&8/$& �$*,7�-�^�/�-0/$F$C�-0F$CE+.&)*,:�C�U_-0Fa&)/'�BPQ-�=q7E-6^t*BA<:�C�&\+./$(8H.S$R$&<*E9$&�:�P$+IH.+.*BUO-�^a-0S�*,7�+IR$&�?�-'-TRq?0S�UT7

*,-Z(�:�C�C�Us-0S�* FQ&8&)CLC�&)JT+I&>A�78X�:�R�R�/$&)Ao^{S$/$(>*,+.-0/�:�H.+.*BU0X¡+.R$&8/c*,+5^tU �¡:�A�78X�:�/�R ��=s*,9$-07�& �¡:�A�7 CE:�F$+IR�H.U� ^{-0C�&�=�:�MNF�HI&�Xa*,9$C�-0S$?09p(8-�HIH�:6Pa-0CE:6*,+5J0&�&)`a-0C�*E7�+I/cJ0-�H.JT+I/$?vFQ&8-�F$HI&_A�+.R$&8H5U�R$+.7EFQ&8C�7E&8R :�C�-0S$/$R�*,9�&A"-0CEH.R�3�¥L^<()-0S$CE7�&�X�*E9$&GCE+I7�D]7O+./$(8H.S$R$&q+I/$()CE&8:�7E&)R-0F$FQ-0C�*ES$/$+5*,+I&)7 ^{-0C�&)JT+IH �BR$-T&8C�7 *,-�R�+I7E()-KJ0&8C �¡:�A�7*,9$:6*�(�:�/uPQ&�&�='F$HI-0+5*,&)R�X$-0C<*E-N+./$7E&)C�*�*,CE:�F�R$-T-0CE7�:�/$R�i#CE-��E:6/s9$-�CE7E&)7\+./c*,-�*,9$&f()-'R$&63i�9$&�e�CE&)&_%T-�^t*BA<:6CE&�e�-0S$/$R�:;*,+I-�/j|}ed%�e ~�S$7E&)7�*E9$&�*,&8C�M � ��� ��������� ��"*,-G+IMGF$H5UG*E9�:6*�*,9�&�S�7E&8C�7

:�/$R CE&)R$&)J�&8HI-�Fa&)CE7_-6^<*,9$&G7E-6^t*BA<:�C�&Z9�:�J�&Z(8&)C�*,:�+I/j^{CE&8&)R$-0MG7�*E9�:6*OR$-�/�-�*O:�CE+.7E&qA�+.*,9jF$C�-0F$CE+.&)*,:�C�U

�)­

Page 101: Practical Architectures for Survivable Systems and Networks (Phase

7E-6^t*BA<:�C�& � +./rF�:�C�*E+I()S$H�:�C)X�^{CE&)&8R$-�M *,-h(8-0FcUr:6/$R�^{CE&)&8R$-0M *,-(g9$:�/$?0& ��9�-¤A"&)J�&8C)XL*,9$&�(8-07b*v-�^*,9�&_7E-6^t*BA<:�C�&_MN:�U�-0C\MN:�Uu/$-�*\Pa&�^{CE&8&6Xa7�-N*E9�:6*L*E9$&8C�&@:�C�&O7b*,+.HIH�-0F$FQ-0Cb*,S$/$+5*,+.&87�^{-0C�&8/c*,C�&8F$C�&8/$&)S$CE7+I/ R$&>J0&8H.-0F$+./$?:�/�R�MZ:6+I/c*g:�+./$+I/�?�7ES$(g9r7�-�^t*BA�:�CE&63wi�9�&�e�CE&8&�%'-�^t*BA�:�C�&�e�-0S$/$R$:6*,+.-0/ � &8P�7E+.*E&�:;*9c*E*EF���m�m;A�A�Af3�?�/TS«3�-0C�?�(8-�/]*,:�+I/�7u7�-�^t*BA�:�CE&6X�F$CE-���&)()*E78X�HI+.(8&)/$7E+./$? F$CE-T(8&)R$S$CE&)78Xf:�/�R�7E- -0/�3 n�*u+I/'�(8H.S$R$&)7�:N*,C�&�:6*E+I7�&@PcU�y�+I(g9�:6CERp%T*,:�HIH.MZ:6/s-0/ � � 9cU � ��� � �������� ���+I7LPQ&)*�*,&)CL*,9�:6/�� � �� � � � ���� �|ª9c*�*,F���m0m;A�A�Af3�?0/]S�3�-0CE?]m;F$9$+IH.-07E-�F$9cU$m¤^{CE&8&��B7�-�^t*BA<:6CE&>��^{-0Cb��^{CE&)&8R$-0Mu3�9]*EMNH�~>3 n�*v:6HI7E- R$& �$/$&87Z*E9$&�e %�e��&8/$&)C,:�H�ldS$P$H.+I(s¬W+.(8&)/$7E&| �fl�¬#~�X�A�9�+I(g9�&)/�^{-0CE()&87 ������� �� �� ����F$HIS�7 ������� � �����\A�9$&)CE&�()-0FcU'H.&)^t*NCE&��x]S$+IC�&87Z*E9�:6*NCE&)R$+I7b*,CE+.P$S�*E+I-0/¨|{A�+.*E9�-0CqA�+.*E9$-0S�*Z(g9�:�/$?0&�~NM@S$7b*2/$-6*2CE&)7�*ECE+I(>*Z^{C�&8&8R�-0M *E-h^{S$Cb*,9$&)C(8-�F]Uu:6/$R�(g9�:�/$?0&63i�9$& ¥�FQ&8/2%'-0S$C�(8& ©s-KJ0&8MG&8/c*�9$:�7"C�&8?0+.7�*E&8CE&)RN*E9$&\*E&8CEM�� � �� � � � �����:�7<:f(8&)C�*E+���(8:6*,+.-0/NMN:�C�DQ3

i�9$&<*E&8CEM +I7d7�Fa&)(8+��$&8RqPcU_*,9�&�¥�FQ&8/N%'-�S$CE()& � & ��/$+5*,+I-�/v|ª9c*�*,F���m0m;A�A�Af3�-0FQ&8/$7�-0S$CE()&�3�-0CE?cm6-07ER«3�9c*,MGHt~�X:�H5*,9$-0S�?09u*E9$&8C�&_:6CE&�/$-NC�&87b*,CE+.()*E+I-0/$7�-0/�*,9$&OS$7E&�-�^�7E-�^t*BA�:�CE&O7ES$P ��&8()*L*,-q*,9�:6*\R$& ��/$+.*E+I-0/«3�i�9$&�CE&��x]S$+IC�&8MG&8/c*,7L-�^d*,9$&�¥�FQ&8/�%'-0S$C�(8& � & ��/$+.*E+I-0/s7EFQ&8()+.^tUsS$/$CE&)7�*ECE+I(>*,&)R�CE&8R�+I7�*ECE+.P$S�*,+.-0/ �QR$+I7b*,C�+IP$S�*,:�P$+.H5�+.*BUN-�^#7E-�S$CE()&�(8-TR$&��$FQ&8C�MN+.7E7�+I-0/Z^{-�C�R$&)CE+.J�&8RvA"-0CED]7���()-0/$7b*,C,:6+I/c*,7�-0/v+./c*,&8?�CE+.*BU �'/$-0/$R$+.7E()CE+IMG+I/$:6*,-0CbUF$CE:�()*E+I(8&)7�CE&8?0:�CER$+./$?�+I/�R$+.JT+IR�S�:�HI7)X'?�CE-0S$F�78X¡:�/$R ��&)HIR$7�-�^Y&8/�R$&�:�J0-�C���*,CE:�/$7E+5*,+5J0&�HI+.(8&)/$7E+./$?@-�^YCE+.?09c*,7��(8-�/]*E&>=T*���^{CE&)& H.+I(8&)/$7E+./$? �O:�/$Rw/$-§:�R�J0&)CE7�&h&)`a&8(>*,7u-0/z:�7E7�-'()+�:6*E&8Rw7E-�^t*BA�:�CE&63�i�9$&h¥ Fa&)/¨%T-0S$CE()&©s-KJ0&)MN&)/c* � &8P$7�+.*,&u+I7q9c*E*EF���m0m;A�A�Af3�-0Fa&)/$7E-�S$CE()&�3�-0CE?]mTX�A�9�+I(g9�+./$(8H.S$R$&)7 � C�+I(uy\:�UTMG-0/$R���7 �bi�9$&k<:6*E9$&8R$CE:�H :6/$R�*,9$& <:�[�:�:�C��v:6/$R�*,9�&q¥ Fa&)/j%'-0S$C�(8& � & �$/$+.*E+I-0/�3 �&)(�:�S$7�&�-�^d*,9�&87E&@*E&8C�MN+./$-0HI-�?�U(8-�/�^{S$7E+.-0/$7)X'A"& S$7E&\*,9$&�*,&8C�M �b-0Fa&)/'�BPQ-�= �_*,-OR$&8/$-6*,& 7�-0S$CE()&>�B:KJ6:�+.H�:�P�HI&�(8-TR$&�X'&8/$()-0MGF�:�7E7�+I/$?_Pa-�*E9^{CE&)&f7E-�^t*BA�:�CE&O:�/$Rs¥ FQ&8/'��%'-0S$C�(8&f7E-�^t*BA�:�C�&�3"UZCE&)^{&)CEC�+I/$?q9$&)CE&�*,-q/$-0/�F$CE-0F�CE+I&>*g:�CbU2-0FQ&8/T�BPQ-K=v7E-�^t*BA�:�CE&6X$A�&�&8/�(8-0MGF�:�7�7�*E9$&f&)`a-0C�*E7�-�^YPa-�*E9

*,9�&se�C�&8&s%'-�^t*BA�:�CE&s©s-KJ�&8MG&8/c*v:�/�R *E9$&�¥�FQ&8/�%'-0S�CE(8&s©s-KJ�&8MG&8/c*�3§ \-0/�F$CE-0F�CE+I&>*g:�CbU�-0FQ&8/'��Pa-�=7E-6^t*BA<:�C�&�+I7@+./$(8C�&�:�7�+I/$?0H5U ^{-�S$/$R +I/*E9$&�e�CE&8&u%T-�^t*BA<:6CE&u©s-KJ0&)MN&)/c*�|{7ES$(g9§:�7@*,9�&�e¡C�&8&u%'-6^t*BA<:�C�&e�-0S$/$R$:6*,+.-0/���7 �f  � 7bUT7�*,&)M A�+.*E9r¬�+I/]S'=$~Z:�/�R�*,9$&p¥ FQ&8/w%'-�S$CE()&p©s-KJ0&)MN&)/]*83 "-�*,9�-6^�*E9$&87�&MG-¤J�&8MG&8/c*,7\Pa&)HI+.&)J0&�+I/�:�/$R�:�()*E+.J0&)H.U�F$C�-0MG-�*,&fS$/$()-0/$7b*,C,:6+I/$&)R�CE+.?09c*,7�*,-ZMG-TR$+���(8:6*,+.-0/�:�/$RsCE&)R$+I7��*,C�+IP$S'*,+I-�/v-�^�-�Fa&)/'�BPQ-�=�7E-�^t*BA�:�C�&�3n�*<+.7<:_7E:�Rv(8-�MNMG&8/c*g:6C�UG-0/2MN:�/cUZ()-0MGMN&)CE(8+I:�H¡:�/$RvF�CE-0F$C�+I&>*g:�CbUN7�-�^t*BA�:�CE& R�&)J0&)HI-0F�MN&)/]*E7<*,9�:;*

7E-�MN& -6^#*E9$& MG-07�*<S$7E&>^{S$H�X �$&>='+IP$H.&�X�:�/$RvCE-�P$S$7�*�7�-�^t*BA�:�CE&�()-0MNFQ-0/$&)/c*,7<*,-TR�:�UZ:�CE& /�-0/$F$C�-0F$CE+.&)*,:�C�U-0FQ&8/'��Pa-�=s7E-6^t*BA<:�C�&�F$CE-TR$S$(>*,7)X«-�^t*E&8/�*,9�&_CE&)7ES$H5*,7 -6^�H�:�PQ-0CE7�-�^�H.-¤J�&�X«:�/$R�A�+.R$&8H5U�:�J6:�+.H�:�P$H.&�^{CE&8&O-�^(g9�:�C�?0&L-KJ�&8C�*E9$&LnB/c*,&)CE/$&>*�-0C�A�+.*E92MN+./$+IMN:�H'&8/$()S$M@P$CE:�/$(8&)783L|ªi�9$C�&8&\&>=�:�MGF$HI&)7�-�^�/�-0/$F$C�-0F$CE+.&)*,:�C�U-0FQ&8/'��Pa-�= 7�-�^t*BA<:6CE&�9�:�J�&�PQ&8&8/�F�:�C�*E+I()S$H�:�C�H.U J�:6HIS�:�P�HI&�+I/ *,9$&sF$CE&)F�:�CE:6*,+.-0/§-6^ *,9$+.7NC�&8FQ-0C�*8��*,9�&�f  � � MN:�(87�&)R$+.*E-0C8X«*E9$&q¬��,i � � R$-'()S$MG&8/c*�7�UT7b*,&8MuX#:�/$RjV�UTFQ&8C�H�:6*E&>= � A�9$+I(g9p?0&)/$&8CE:6*,&)7�9]*EMNH^{CE-�M ¬ � i � � 7�-0S$C�(8&�3�~� =�:�MNF�HI&87�-6^�-0FQ&8/T�BPQ-K=�7E-�^t*BA�:�C�&GA�+5*,9$+./�*,9$&qe�CE&)&G:�/$R ¥ Fa&)/'�b%'-�S$CE()&G7�-�^t*BA�:�CE&G(8-0MGM@S$/�+.*,+.&87

+I/�(8HIS�R$& ��l�¬«�B&)R 7�-�^t*BA<:6CE&�|{&�3�?$35XYi�9$& �f  � %TUT7�*E&8M A�+.*E9h¬�+I/]S'=aX ��  � � MN:�(87)X ��k�kLX �f/�-0MN&�'3���X �f9$-�7�*EJT+.&)AfX ��  �\7E(8:�FQ&@ L:�JT+I?0:6*,-0C)X¡?0[8+.F�X � :�J6:NF$:�(gD;:�?0&87,~L:�/$R�e¡C�&8& �f% � �Q/$-�*\x]S$+.*E& �fl�¬��&8R�7E-�^t*BA�:�CE&u|ªlY&)CEHt~ �«/$-�/'� �fl�¬h^{CE&8&_7E-�^t*BA�:�CE&v|}e�CE&)& �% � X � A�+./$R$-KA�78X � F�:6(g9$&�X�¬��Ei � � X«©s-0[)+IHIHI:�X \&>*,7�(�:�FQ& � :�J6:c%'(8C�+IF�*�3.353�~ � :6/$R ¥ Fa&)/ �% � X" \&>* �% � X�V�U'FQ&8C�H�:6*E&>=aX � :�[8&)H ��7v¬�+I/]S'=§?0CE:�F$9$+.(�:�H7E9�&8HIH}X�3.353f|�� ��  � �G+I7\:GC�&8()S$CE7�+.J0&_:�(8C�-0/cUTMsX¡CE&)F$CE&)7E&)/]*E+I/$? � ��  ��+I7\ \-�* �\/�+5= �$3�~v¥ *E9$&8C�HI+.(8&)/$7E&)7PQ&87E+.R$&87 �fl�¬h+I/$()HIS$R�&�©�l�¬:�/$R���l�¬��$MG-0C�& J�:6CE+�:6/]*E7�:�CE&fH.+ID�&)H.UG*,-G&8MG&8C�?0&�+I/v*,9�&f^{S'*,S$C�&�3i�9$&NCE-0H.&87_-6^�-0FQ&8/'��Pa-�= 7E-�^t*BA�:�C�&2+I/ R$&)J�&8HI-�F$+I/$?�9$+I?09�H.U�7�S$C�JT+.J6:�P�HI&Z7bUT7�*,&)MN7@:�CE&Z:sCE&)(8S$C�CE+./$?

*,9�&8MG&�+I/�*,9�&�CE&87b*u-�^f*,9$+.7vCE&8FQ-0Cb*�X�+I/rHI+.?09c*v-�^Z|{^{-�C2&>=�:�MGF$HI&�~N*,9$&�nB/c*E&8CE/�&)*�X\*BU'F�+I(�:6HIH.U �¡:�A"&8R-0FQ&8CE:6*,+./$?�7�UT7�*E&8MG78X¡JTS$HI/$&)C,:�P�HI&�7�UT7b*,&8M &)M@Pa&)R$R$+./$?07�-�^Y7�*,C�-0/$?G(8CbU'F'*,-0?0CE:�F$9cU0XQ:�/�Ru*E9$&fF$CE&)7E&8/�(8&-�^�MG-0P$+.HI&�()-'R$&63 � /2:�CE(g9$+5*,&)()*,S�C,:�H¡7ES�Pax]S$&)7�*,+.-0/2+./]J�-0H.J�&87�A�9$&8C�&\*,C�S$7�*BA"-0Cb*,9$+./$&87�7<M@S$7b*<PQ&\F$HI:�(8&)R

��

Page 102: Practical Architectures for Survivable Systems and Networks (Phase

*,-�MG+I/�+IMG+I[8&�*E9$&�:�MG-0S$/c*�-�^�(8C�+.*E+I(�:6H"()-'R$&�:6/$R�*,-p:�(g9$+.&)J�&uC�-0P$S$7b*,/$&)7E7q+I/*E9$&vF$C�&87E&)/$(8&�-�^�*,9�&7EFQ&8()+���&)R�:6R�J0&)CE7E+5*,+.&878XQ:�/�R�*E9�:6*�x]S$&87b*,+.-0/s+.7�:�R$R$C�&87�7E&8Ru^{S$C�*E9$&8C�+./�k�9$:�F�*,&)C\�'3� 9�+I?09$H5U�-KJ0&8C�7E+.MNF$H.+���&)R�x]S$&)7�*,+.-0/�+.7\^{CE&)x]S$&8/c*,H5U�:67ED�&)R�� � � +IH.H#-�Fa&)/'�BPQ-�=�7�-�^t*BA�:�CE&@C�&�:�H.H.U�+.Mq�

F$C�-¤J�&L7bU'7b*,&)M 7�&8(8S�CE+.*BU�� �ji�9$&L-0PcJT+I-�S$7�:6/$7�A"&8C"+I7 � � � � � �� � � � � ��� � � � ��� ��� � � � � �� �� ���� � ��� � �� � ������� ���©�:�/cUu-�*,9$&)C�^ª:�()*E-0CE7�M@S$7b*LPQ&O()-0/$7�+IR$&)CE&8R«3<nB/$R$&)&8R�XaMZ:�/cUv-6^ *,9$&�F$C�-0P$HI&)MN7�-�^�P$H�:6(gDc��Pa-�=7E-6^t*BA<:�C�&q(�:�/j:�H.7E-vPQ&�F$CE&)7E&8/c*O+I/�-0FQ&8/T�BPQ-K=�7E-�^t*BA�:�C�&�XY:�/$R � �� � ��� ��|{^{-0C�&�=�:�MNF�HI&�X �¡:�A�&)RhR$&��7E+.?0/$7)XW*E9$&qCE+.7ED]7O-6^�MG-0P$+.HI&@()-'R$&6X#:u7�9$-0C�*,:�?0&q-�^"?0+.^t*E&8Rp7�UT7b*,&8M :�R�MN+./$+I7b*,C,:;*,-0C�78X�:�/�R 7�-s-0/�~>3qnB/*,9�&�:�P$7�&8/$()&�-6^¡7E+I?�/$+���(8:�/c*dR$+.7E(8+.F$HI+./$&":�/$R�+I/�9$&8C�&8/c*,H5U_PQ&)*�*,&8C�7�UT7�*E&8M :�C�(g9$+.*E&8(>*,S$C�&878Xc-�F$Fa-�C�*,S�/$+.*E+I&87MN:KUpPQ&Z&>J0&)/�MN-0C�&�A�+IR$&)7EF$C�&�:�Rh^{-�CO+./$7E&)C�*,+.-0/j-�^�MN:�HI+.(8+I-�S$7�(8-TR$&G+I/ *E9$&ZR�&)J0&)HI-0F�MN&)/]*_F$CE-T(8&)7E7)X:�/$R�^{-0C�S$/�(8-0/c*,C�-0HIH.&8R�7ES�P]J�&8C�7E+I-�/$7\-6^Y*E9$&f-0Fa&)C,:6*E+I-0/$:�H�F$C�-'()&87E7)3nB/s:6*E*E&8MGF�*,+./$?@*,-q&>='F$H.-0+.*�-�Fa&)/'�BPQ-�=�7E-�^t*BA�:�C�&�X$A"&�^ª:�()&�:GP�:67E+I(�()-0/ ��+.()*�PQ&)*BA"&8&8/�|}:c~�7�&8(8S�CE+.*BU

PcU -0P$7�(8S$C�+.*BU*E-j7�HI-KA R�-¤A�/ *,9�&�:�R'J0&8C�7,:�C�+I&)78X<:6/$R¨|{P¡~_-0FQ&8/$/�&87E7G*,-j:�H.HI-KA ^{-0C�MN-�CE&2*,9�-0CE-0S�?09:�/�:6H.UT7E+.7\:6/$Rs()-0HIHI:�PQ-0C,:6*E+.J�& +IMGF$CE-KJ�&8MG&8/c*�-�^ ()CE+.*E+I(8:�H�7�UT7b*,&8MG7 � :�7�A"&8H.HY:67\F$C�-KJ'+.R$+I/�?N:�^{-0C�(8+I/�?^{S$/$(>*,+.-0/*,-p+I/�7EF$+.CE&2+.MNF$C�-KJ0&8MG&8/c*E7�+I/*,9�&2^ª:�(8&v-�^�R$+.7E()-¤J�&8C�&8R�:;*E*g:6(gDh7E()&8/�:6CE+I-�783 � =�:�MGF$HI&)7@-�^:�/�:6H.U]*,+.(L*,-T-0HI7<^{-�C�&)J6:�HIS$:6*,+./$?@-0FQ&8/'��Pa-�=�7�-0S$C�(8&�(8-TR$&f+I/$()HIS$R$&

2 9c*�*,F���m0m6+.MNM@S�/$+5=a3�-0CE?$� k�CE+.7EF$+./�k�-KA�:�/���7 %]*g:�(gD ��S�:�CER2 9c*�*,F���m0m;A�A�Af3�(87)3�PQ&8C�D�&8H.&)U�3�&)R$S¡m � R$:KA\m;F�:�FQ&8CE7,m'� � :�JT+IR � :6?0/$&8C ��7�P$S'`«&)C�-KJ�&8C �$-¤A¦:6/�:�H.UT[)&8C2 9c*�*,F���m0m;A�A�Af3�H���F�9]*83�()-0MZm67EH.+I/c*�3�9c*,MGH��¨¬W��F�9]* ��7�|ª/�-¤A��f%T*g:�D6& ��7g~�7E&)(8S$C�+.*BUoC�&)JT+I&>A :�/�:6H.UT[8&)C7�HI+./]*

2 9c*�*,F���m0m;A�A�Af3�CE7b*,(8-�CEF�3�(8-0MZm6+5*,7E1cm'��y�&)HI+I:�P$HI&\%'-6^t*BA<:�C�&�iY&)(g9$/$-0H.-0?�U ��7�nBi�%'1�^{S$/$()*E+I-0/T�B(�:6HIHQ:�/�:;�H5UT[8&8C<^{-�C�kz:�/$R�k���� (8-TR$&

nBR$&8:�HIH5U0X�+5^Q: 7�UT7�*E&8M +.7 MG&�:�/$+./$?�^{S$H.H.U�7�&8()S$CE&6X'-0FQ&8/�7�Fa&)(8+���(�:6*E+I-0/�7d:�/$R�-0FQ&8/T�BPQ-K=@7E-0S�CE(8&�7�9$-0S$H.R/$-�*"PQ&L:�7E+I?�/$+���(8:�/c*�Pa&)/$& �$*"*,-O:6*E*,:�(gD�&)CE7)X$:�/$RG*,9$&\R$&)^{&)/$R$&)CE7<MG+I?09c*�PQ&L:6P$HI&�*,-OMZ:6+I/c*g:�+./q:O()-0Mq�FQ&)*,+5*,+5J0&f:�R�J6:�/c*,:�?0&���e�-0C�&>=�:�MGF$HI&6X$*,9$+.7�+I7<*,9�&OF$C�+I/$()+IF$H.& PQ&89$+./$RsS�7E+I/�?N7b*,CE-�/$?N-�Fa&)/$H.UvF�S$P$HI+.7E9$&)R(8CbUTF�*,-0?�C,:�F$9�+I(q:�H.?0-0CE+5*,9$MG7 � ^{-�C A�9$+I(g9 :�/�:�H5UT7E+I7�-6^<:�H.?0-0C�+.*,9�MN7L:�/$Rp*,9$&)+IC�+IMGF$H.&8MG&8/c*g:6*E+I-0/�7\+.7J0&)C�UGJ6:�HIS�:6P$HI&6X':6/$RZA�9$&)CE& -0/�H.U�*,9�&LF$C�+.J6:6*,&�D�&>UT7</$&8&)R2*,-OPa&\9$+IR$R�&8/�3�¥L*,9�&8C�&�=�:�MNF�HI&87�-�^�-�P$7E()S'�CE+5*BU2+./$(8H.S$R$& *g:6MNFQ&8C�F$CE-T-���/$?q:6/$R�-0P�^{S$7�(�:6*E+I-0/�3 ��/�^{-0Cb*,S$/�:;*,&8H5U0X$MN:�/cUv&�=�+.7�*E+I/$?q7�UT7b*,&8MG7�*,&)/$Ru*E-PQ&NFQ-'-�CEH.UsR$&)7E+I?�/$&8Rh:�/$RhFQ-T-0CEH5U�+IMGF$H.&8MG&8/c*,&)R�X�A�+.*E9 C�&87EFQ&8(>*_*E-s+./$(8-0MGF$H.&)*,&q:6/$R +./�:�R$&)x]S�:6*,&)H.U7EFQ&8()+���&)RsC�&8x]S$+.CE&8MG&8/c*E783 � &)J�&8HI-�Fa&)CE7�:�CE& *E9$&8/u:6*�:�R$&)(8+.R$&8R�R$+.7,:�R�J6:�/c*,:�?0&�X�&>J0&)/uA�+5*,9�P$H�:6(gDc��Pa-�=7�UT7b*,&8MG783 �&)7E+IR�&878X�CE&87�&�:�C�(g9�+./$+.*E+�:6*E&8R+./§: 4K¢ �6��F�:�FQ&8CqPcU � R�©s-T-0CE& ���0�'4 �CE&8MG+I/�R$7�S$7�*,9�:;*F$S$C�&8H5Uv&>=T*,&)CE/�:6H�� � � � � ��� L&>='FQ&8C�+IMG&8/c*,7�-0/uP$H�:6(gDc��Pa-�=�7bUT7�*,&)MN7�(�:6/�-�^t*E&8/uR$&)*E&8CEMG+I/�&�+I/c*,&)CE/�:�H7�*,:6*,&fR$&>*g:�+.HI7)3�&)9�:�J'+.-0C,:6H$7�UT7�*E&8M C�&8x]S$+IC�&8MG&8/c*,7�7�S$(g92:�7�7E:6^{&)*BU�XTC�&8H.+�:�P$+.HI+5*BU0X6:�/$RqCE&8:�H5��*,+IMG&�FQ&8Cb^{-0CEMN:�/$()&�(�:�/T�

/$-�*@Pa&vC�&�:�H.+I7�*E+I(8:�HIH5Up:�(g9$+.&)J0&)R§S�/$HI&)7E7@*,9�&v7�UT7�*E&8MG7N:6CE&�:�R$&)x]S�:6*,&)H.Uh7E&8()S$CE&63n�*q+I7OJ0&8CbU�R$+��N()S$H.**,-qP$S�+IHIR�C�-0P$S$7b*L:6F$F$HI+.(�:6*E+I-0/�7<P�:�7�&8R�-�/uF�CE-0F$C�+I&>*g:�CbUvP$H�:6(gDc��Pa-�=�7�-�^t*BA�:�CE&f*,9�:;*�+I7�/$-�*�7�S��G(8+I&)/c*,H.U*,C�S$7�*BA"-0Cb*,9cU03i�9$&�4�¢ ���sF$:�Fa&)CE7@PcU � -09$/hJ�-0/  \&8S�MZ:�/�/ � ��£�1 <:�/$R�PcU�©u-'-0C�&2:�/�R %'9�:�/$/�-0/������0� �/$-�*,&)R

+I/u%T&8()*E+I-0/�4�3��_7�9$-KA�&)Rs9$-KAw*,-�()-0/$7�*ECES$(>*�CE&)HI+�:6P$HI&\(8-0MGFa-�/$&8/c*,7�-0S�*�-�^WH.&87E7�C�&8H.+�:�P$H.&\()-0MGFa-0/�&8/c*,7)3¬W:6*,&)C�A"-0C�D�-0/Z()-0CEC�&8()*"PQ&89�:�JT+I-0C�R$&)7EF$+5*,&�7E-0MG&�/TS�M@Pa&)C"-6^�:�C�P$+.*EC,:�C�+IH.UOFQ&8C�J�&8C�7E&��U'[8:�/c*,+./$&\^ª:�S�H.*,7^{-0H.HI-KA�&)R:�H.-0/$?�*,9$-�7E&ZH.+I/$&)783�nB/h*E9�:6*O(8-0/c*,&�=T*�XdP$S$+.HIR$+./$?u:s^ª:�S$H5*���*,-0H.&8C,:6/]*f7�+IH.D�F$S$C�7E&2-0S'*_-�^�H.&87�7CE-�P$S$7�*�7�-¤A ��7�&�:�C�7�+.7d+I/$R�&8&8RGFQ-07E7�+IP$H.&�+I/q7E-0MG&�(�:67E&87)3 �S�*�(8-�/$7�*ECES$(>*,+I/�?OMG-0CE&<*ECES$7b*BA�-�C�*,9cUq7�&8(8S�CE&

���

Page 103: Practical Architectures for Survivable Systems and Networks (Phase

7�UT7b*,&8MG7�-0S�*�-�^QH.&87E7 *ECES$7b*BA�-�C�*,9cUq7�S$P$7�UT7b*,&8MG7�R$-'&)7d/$-�*d7�&8&)M CE&8:�HI+.7�*,+.("A�9$&)/G*E9$&�S$/$R�&8CEH5UT+I/$?�()-0Mq�FQ-0/$&8/c*E7�:�C�&�(8-0MGF$CE-�MN+.7E+IP�HI&�X6R$&87�F$+.*E&\&>`«-�C�*,7�7�S$(g92:�7�A�C,:6F$Fa&)Cd*,&8(g9�/$-0HI-�?�Uq:�/$R ��CE&>A<:6HIH�+I7�-0H�:;*,+I-�/�3

� 9$&)/$&)J�&8C�:�(g9$+.&)JT+I/$?f7�&8(8S�CE+.*BU_PcU�-0P$7�(8S$C�+.*BU@+.7 /$-�*�*,9$&�F$C�+IMN:�C�U�?0-0:�H�X�*E9$&8C�&�7E&)&8M *E-�Pa&�7b*,CE-�/$?:�C�?0S$MG&8/c*,7�^{-�C�-0FQ&8/'��Pa-�=_7E-�^t*BA�:�C�&�*,9�:;*d&8/$()-0S$CE:�?0&87d-�Fa&)/@CE&>J'+.&)A§-�^¡CE&)x]S$+IC�&8MG&8/c*,7)XcR$&87�+I?0/$7)X07EFQ&8(��+��$(�:6*E+I-0/$7)X0:�/�R�(8-TR$&�3 � J�&8/qA�9$&8/�-�P$7E()S$CE+5*BU@+I7YR$&8&)MN&)R�/$&8()&87�7,:�CbU0X]7E-0MG&�A�+.R$&8C��B(8-�MNM@S�/$+.*BUf-0FQ&8/T�PQ-K=N:6F$F$CE-0:�(g92+I7�R$&)7E+.C,:�P$H.&�3de�-0C�7�-�^t*BA<:6CE& :6/$RN^{-0C�7�UT7b*,&8M :�F$F�HI+I(8:6*,+.-0/$7d+./GA�9$+.(g9Z7�&8(8S�CE+.*BUG(8:�/2PQ&:�7�7ES$C�&8RvPcUG-�*,9$&)C�MG&�:�/�7�:�/�R2+I7�/$-�*"(8-0MGF$C�-0MN+.7E+.P$HI&�A�+5*,9$+./G*E9$& :6F$F$HI+.(�:6*E+I-0/q+5*,7E&)H.^�Xc*,9�&L-0FQ&8/'��Pa-�=:�F$F�CE-c:�(g9j9�:�7fF�:6C�*,+.(8S$HI:�CEH5Uu?0CE&8:6*�:�F$FQ&�:�H}3@nB/ :�/cU�&)J�&8/c*�XY+.*�+.7f:�H.A�:�U'7fS$/cA�+.7E&q*,-�CE&)H.U �� � � �_-0/-0P$7�(8S$C�+.*BU�3%'-$X#A�9�:6*O&8H.7E&Z+.7f/$&8&)R$&8R*E-�:�(g9$+.&)J�&Z*,C�S$7�*BA"-0C�*E9cUhC�-0P$S$7b*@7�UT7b*,&8MG7_*E9�:6*_:�CE&GF$CE&)R$+I(>*g:�P�H.UpR$&��

FQ&8/$R�:6P$HI& � i�9�& ��C�7�*b�BHI&>J0&)H\:6/$7�A"&8CG+I7�*,9�&s7E:�MN&v^{-0C�-�Fa&)/'�BPQ-�= 7�UT7�*E&8MG72:�7�A"&8H.H�:�7N()HI-07�&8R'��Pa-�=7�UT7b*,&8MG78�\7E&)CE+I-�S$7LR$+.7E()+IF$H.+I/$&f*,9$C�-0S$?09�-0S�*L*E9$&@R$&>J0&)HI-0F$MG&8/c*�(>UT(8HI&@:�/$R�-0FQ&8CE:6*,+.-0/�:�HWF$CE:�()*E+I(8&6X«S$7�&-�^#?0-T-'Rv7�-�^t*BA�:�CE&�&)/$?0+I/�&8&8C�+I/$?�X$CE+.?0-0CE-�S$7�C�&8FQ&�:6*E&8Ru&)J6:�HIS$:6*,+.-0/$7�-6^Y7bUT7�*,&)MN7�+./2*,9$&)+IC<&)/]*E+IC�&)*BU0X¡:6/$R&8/�HI+I?�9]*E&8/$&)RsMN:�/�:6?0&8MG&8/c*�XT^{-0C�7�*,:�C�*E&8C�783� 7E&)(8-0/�R'�BH.&)J0&)H¡:�/$7bA�&)C�+./cJ0-0H5J0&87�+./$9$&8C�&8/c*,H5U@C�-0P$S$7b*�:6/$Rq7E&8()S$CE&�&>J0-0H5J�:6P$HI&�+./]*E&8C�-0Fa&)C,:�P�HI&�:�C�(g9$+5�

*,&)()*ES$CE&)7 *,9�:6*d:KJ�-0+IR_&>='(8&)7E7E+5J0&�R$&8FQ&8/�R$&8/$()&�-0/�S$/c*,C�S$7�*BA"-0C�*E9cU�(8-0MGFQ-0/$&8/c*E783�¥L^¡(8-�S$CE7�&�X]Fa-6*,&8/c*E+�:�HCE+.7ED]7 (8:�/pPa&�:67E7E-T(8+I:6*,&)R�A�+.*E9�/$-0/$F$C�-0F$C�+I&)*,:�C�Uu7�-�^t*BA<:6CE&q:�7 A"&8H.H :�7 F�CE-0F$C�+I&>*g:�CbU�7�-�^t*BA<:6CE& � ^{-�C&>=�:�MGF$H.&�X C�&8H�:;*,+I/�?s*,-�*E9$&v:�S'*,9$&)/]*E+I()+.*BU -�^�*,9$&Z7E-0S$C�(8&)7N:6/$Rh*,9�&2*,CES�7�*BA"-0C�*E9$+I/$&)7E7�-�^�*E9$&2R$+.7�*,C�+5�P$S�*E+I-0/pF�:;*,9$7)3Ni#-s()-0M@P�:;*f-0CER$+./�:�CbU�(8-TR$&q9�:�(gD]+I/�?�:�7�A"&8H.H�:�7�*,9$&�*,9�CE&8&q^{-0C�MN7�-�^"(8-�MNF$C�-0MG+I7E&/$-�*E&8RN+I/Z%'&8(>*,+I-�/s403 ��XT:fP$CE-c:6R'�B7�Fa&)()*,C�S$M (8-�M@P$+I/$:6*,+.-0/q-�^«*E&8(g9$/$+.x]S$&87"+I7�R$&87�+ICE:�P$HI&6X]+I/$()HIS$R$+./$?N|{^{-0C&>=�:�MGF$H.&K~<(8CbU'F'*,-0?0CE:�F$9$+.(f(g9$&8(gD]7ES�MN7)X«*,C�S$7�*BA"-0C�*E9cU�7�-�^t*BA<:6CE&�R$+I7b*,CE+.P$S�*E+I-0/�(g9�:�/�/$&8H.78Xa:�/$RuF$S$P$H.+I(>�D�&>Uu:�S�*E9$&8/c*,+.(�:6*E+I-0/v7�(g9$&8MG&87)X�A�9$+I(g9v*,-�?0&)*E9$&8C�(8:�/s-KJ�&8CE()-0MG&�7�-0MG&�-�^W*,9$&fS$/$()&8Cb*g:�+./]*BUv:�7<*,-�*,9�&*,C�S$7�*BA"-0Cb*,9$+./$&87�7�-�^�:�/cU�()-'R�&OJ0&)CE7�+I-0/�*E9�:6*LU�-0S�MG+I?09c*�Pa&_S$7E+./$?$3�¥ /$&O-�^d*,9�&_F$C�+IMN:�C�Uu:�C�(g9$+.*E&8(��*,S�CE&87�()-0/$7�+IR$&)CE&8R +./*,9$+.7_CE&)Fa-�C�*�+./]J�-0H.J�&87@*E9$+I/'��(8H.+I&8/c*_S$7E&)C�F$H�:6*�^{-0CEMG7fA�+.*,9�MG+I/�+IMN:�Hd-0FQ&8C,:;*,+I/�?7�UT7b*,&8MG78X$A�9�&8CE& *ECES$7b*BA�-�C�*,9�+I/$&)7E7�+I7�PQ&87b*,-KA"&8R�A�9$&8C�&�+5*<+.7<&87�7E&8/c*E+�:�H � *BU'F�+I(�:6HIH.U�X'+./27E&)C�J�&8CE7)X ��CE&��A�:�HIH.78X¡(8-TR$&�R$+I7b*,CE+.P$S�*E+I-0/�F�:6*E9$78XQ/$-0/�7EFQ-'-�^ª:6P$HI&fF$C�-¤J�&8/�:6/$(8&_^{-�C\()CE+.*E+I(8:�H�7E-6^t*BA<:�C�&�Xa(8C�UTF�*E-0?0CE:�F$9$+.((8-;�BF$C�-'()&87E7�-0CE7)X"*,:�MNFQ&8C�F$CE-T-�^�&)M@Pa&)R$R$+./$?078X�F$C�&)J0&)/c*,+I/�? R$&)/$+�:6H5�B-6^��B7E&)C�JT+I()&2:6*�*g:�(gD]7)X"C�S$/'��*E+IMG&2R$&��*,&)()*E+I-0/v-�^WMN:�H.+I(8+.-0S$7�(8-TR$&�:6/$R�R$&)JT+�:6/]*<MN+.7ES$7�&�X$:6/$Rv7E-�-0/«3 � HI&)7E7<^{&�:67E+IP�HI& :6H.*,&)CE/�:;*,+.J�&L+./Z*,&)CEMG7-�^#*,-TR�:�U ��7�*,&)(g9$/$-0H.-0?�Uv+./cJ0-0H5J0&87�M@S�(g9�MG-0CE&L*ECES$7b*BA�-�C�*,9cUu&8/�R'�BS$7�&8C�F$H�:;*E^{-0C�MN7)3� *,9�+ICERT�BHI&>J0&)H$:�/$7bA�&)C�+I7 *,9$:6*d*,9$&)CE&�+.7d7�*,+.HIHTM@S$(g9GCE&)7E&�:6CE(g9qU0&)*�*E-�PQ&�R$-0/�&_|{7ES$(g9N:�7d-0/qC�&�:�H.+I7�*E+I(

(8-�MNFQ-07E+5*,+.-0/�:�H.+.*BU0Xc+./$9$&)CE&8/c*EH.UNCE-0P$S�7�*�:�C�(g9$+.*E&8(>*,S$C�&878X¡:6/$Rv-0FQ&8/'��Pa-�=ZP$S$7E+./$&87�7�MN-TR$&)HI7g~�X�:67<A�&)HIH�:67MG-0CE&O&)`a-0C�*E7\*,-vP�CE+I/�?N*,9$:6* C�&87E&8:�CE(g9p+./]*E-2F$CE:�()*E+I(8&63 � `«&)()*E+.J0&@*E&8(g9$/�-0HI-0?6Uu*EC,:�/�7�^{&8CL7E&8&)MN7LM@S$(g9MG-0CE&�H.+ID�&)H.UG*,-G9�:�F$FQ&8/u+I/v-�Fa&)/'�BPQ-�=�7�UT7�*E&8MG783 \-�/$F$CE-�F$CE+.&)*g:6C�Uv-0FQ&8/T�BPQ-K=v7�UT7�*E&8MG7 :�C�&�/�-�*\:GF�:6/�:�(8&8:�3�V�-¤A"&)J�&8C)XQ*E9$&)Uu9�:�J0&�FQ-�*,&)/]*E+�:�H�PQ&8/T�

& ��*,7�*,9$C�-0S$?09�-0S�*@*E9$&vF$CE-T(8&)7E7q-�^�R$&>J0&8H.-0F$+./$?j:�/$R -0FQ&8C,:;*,+I/�?�(8C�+.*,+.(�:�H�7�UT7b*,&8MG783hnBMNF$C�&87�7E+.J�&�Pa&��?0+./$/$+I/�?07G:�HIC�&�:�R�U &�='+I7�*83  \&>J0&8Cb*,9$&)HI&)7E78X�M@S$(g9�&)`a-0C�*NCE&)MZ:�+./$7q+I/§F$CE-KJT+IR$+./$?p*,9$&u/$&8()&87�7,:�CbU�R$&��J0&)HI-0F�MN&)/]*LR$+I7�(8+.F$HI+./$&�XQ:�R$&)x]S�:6*,&_(8-0/c*,C�-0HI7\-KJ0&8C\*,9$&O+I/c*,&)?0CE+5*BUs-6^ *,9$&_&8MG&8CE?�+I/$?G7E-�^t*BA�:�C�&�X�7bU'7b*,&)M:�C�(g9$+.*E&8()*ES$CE&)7�*,9�:6*�(8:�/u7,:6*E+I7�^tUZ(8C�+.*,+.(�:�HaCE&)xTS�+ICE&)MN&)/c*,78X¡:6/$RuA"&8H.H5��R$-'()S$MG&8/c*,&)RuR�&8MG-0/$7�*EC,:6*E+I-0/�7<-�^*,9�&OPQ&8/$& �$*,7\-�^ -�Fa&)/'�BPQ-�=�7�UT7�*E&8MG7L+./u*E9$&OC�&�:�H�A"-0CEH.R�3�n�^�/$-�*E9$+I/$?G&8H.7E&6XQ-�Fa&)/'�BPQ-�=�7ES$()(8&)7E7E&)7�MZ:�U9�:�J0&u:�/�+./$7EF�+IC,:;*,+I-�/�:�H�&)`a&8(>*q-0/�(8-0MGMG&8CE()+�:�H�R$&>J0&8H.-0FQ&8CE7)XdA�9$-p(�:�/ C,:6F$+IR$H5U :�R$-0F�*_*,9$&vPQ&87b*�-�^*,9�&\C�&87ES�H.*,7)3 �S�*�*,9�&\FQ-07E7�+IP$+.HI+5*,+I&)7 :�C�&\()-0/$7�+IR$&)C,:�P$H.&�^{-0C�(8-09$&)CE&)/]*"(8-�MNM@S�/$+.*BU�()-'-�Fa&)C,:6*E+I-0/q+I/q*,9�&R$&>J0&8H.-0F$MG&8/c*�-�^Y/$-0/$F$C�-0F$C�+I&)*,:�C�U2-0Fa&)/'�BPQ-�=v7�-�^t*BA<:6CE&�X¡&)7EFQ&8(8+I:�HIH5U2+5^�:6R$&8x]S�:6*E&8H5Uv7ES$F�Fa-0Cb*,&)R�3�&)(�:�S$7�&�7E-0MG&�-�^�*E9$&�7E&)CE+I-�S$7�7�UT7�*E&8MG+I( R�& ��()+I&8/�(8+I&)7�:�CE& /�-�*�HI+.D�&)H.Uq*,-�PQ&�-KJ0&8C�(8-0MG&�+I/ZF$CE-0F�CE+5�

&)*,:�C�Us7�UT7b*,&8MG7G|�%T&8()*E+I-0/�1$3 �0~>X«+5*\A"-0S$H.R�PQ&@9$+I?�9$H.Uu:�R'J�:6/]*,:�?0&)-0S$7L*E-2MZ:6D�&@MG-0CE&�7�UT7b*,&8MN:6*E+I(@S$7�&

� �

Page 104: Practical Architectures for Survivable Systems and Networks (Phase

-�^Y/$-0/$F�CE-0F$C�+I&>*g:�CbUZ7�-�^t*BA<:6CE&�X¡&)7EFQ&8(8+I:�HIH5UZ+5^W*,9$&�7�-0S$CE()&f(8-TR$&f+I7�-0FQ&8/$H5U2:�J6:�+.H�:�P$H.&�X':�/$R�+.^#+5*�(�:�/uPQ&MN:�R$&@MG-0CE&_CE-0P$S�7�*�*,9$:�/p+.*,7LF$CE-0F�CE+I&>*g:�CbU�()-0S$/c*,&)CEF�:6C�*,7)X�:6/$R�+.^�*,C�S$7�*BA"-0Cb*,9cUpR$+I7b*,C�+IP$S�*E+I-0/sF�:6*E9$7(�:6/Pa&Z&87�*,:�P$H.+I7E9�&8R�:�/�RS$7E&)R�(8-0/�7E+I7b*,&)/]*EH.U +I/h:s*,C�S$7�*BA"-0C�*E9cUMN:�/$/$&)C83 � HI7�-�+IMGFa-�C�*g:6/]*�+.7O*,9�&7�UT7b*,&8MN:6*E+I(�S$7E&�-�^ /�-0/$F$C�-0F$CE+.&)*,:�C�Uv+./c*,&8Cb^ª:�(8&f7b*g:�/$R$:�CER$7�*,9�:;*\9$:KJ�&OPQ&8&)/�&>='F$H.+I()+.*,H5UZ()CE&8:6*,&)RsA�+.*E9+I/c*E&8CE-�Fa&)C,:�P$+.HI+5*BUN+./�MN+./$R�3l�:6C�*,+.(8S$HI:�CEH5U�7E&)CE+.-0S$7�FQ-�*E&8/c*,+I:�H¡F$CE-0P�HI&8MG7�A�+.*,9NiYC�-��E:�/29�-0CE7�&87<MG+I?09c*"Pa&\+IMGF$H�:6/]*E&8RG+I/GJ�:6CE+�:6/]*

J0&)CE7�+I-0/$7�-�^Y-0FQ&8/'��Pa-�=27E-�^t*BA�:�CE&63 � F$:�C,:�R�+I?0MN:6*,+.(\C�+I7�DZ+I7�F�CE-KJT+IR$&)RuPcU���&)/si�9$-�MNF$7�-0/���7\k ()-0Mq�F$+.HI&8C�&�=�:�MNF�HI& ���c�0��}X�/$-�*E&8R�+./s%'&8(>*,+I-�/ 403 ��3�nB/s^ª:�(>*�X�()-0MNF�+IHI&)CE7�S$7�&8Ru*,-GF$CE-TR$S$()&O()CE+.*E+I(8:�H5��7�UT7�*E&8M(8-TR$&vF$C�&87�&8/c*G7E-0MG&v7EFQ&8()+�:�H"F$CE-0P�HI&8MG783 �&8H.HI-KJT+I/���7@:6F$F$CE-0:�(g9�*,-pS$7E+./$?�^{-0C�MZ:�H�J0&)CE+���(�:6*E+I-0/����c��+I7�CE&)HI&>J�:6/]*_+I/R�&8MG-0/$7�*EC,:6*E+I/$?u(8-�/$7E+.7�*,&)/$()UhPa&>*BA�&)&8/ 7E-�S$CE()&2(8-TR$&2:6/$R-0P���&)()*�()-'R�&�X�A�9$+.(g9�+I7O:F�:�Cb*,+.(8S$HI:�CEH5U@*,9$-�CE/cUZF�CE-0P$H.&8M A�9$&)/v+I/$7�+IR$&)CE7 |ª7ES�(g9s:67<��&8/2i�9�-0MNF�7E-0/ ��~�:�CE&L:�P$H.&�*E-_*,+./$D�&)C"A�+.*E9*,9�&�()-0MGF$+IH.&8C<+5*,7E&)H.^�3n�*"+I7�S$/�^{-0Cb*,S$/�:;*,&\*E9�:6*"7E-_^{&>A CE-0P�S$7�*�-0Fa&)/'�BPQ-�=G7E&)(8S$C�+.*BUN7�UT7�*E&8MG7<&>='+I7b*�XTF�:�Cb*,+I()S$H�:6CEH.U@Pa&)(�:�S$7�&

(8H.-07E&)R'�B7�-0S$C�(8&�7�UT7�*E&8MG7 CE&)F$CE&)7E&8/c* :qJT+I-�H�:6*E+I-0/v-�^Y*,9$&�F$C�+I/$()+IF$H.&�-6^ 7E()CES�*,:�P$+.HI+.*BU�|ª7�&8&�%T&8()*E+I-0/��'354¤~>3nB/�:ZC�&8()&8/c*�(8-�MNM@S�/$+I(8:6*,+.-0/�Xa%T*g:6HIHIMN:�/�/$-�*E&87L*E9�:6*�*,9$& ��  � ldCE- ��&8()* +I7\A"-0C�DT+./$?2-0/�e¡C�&8&@%'-�^t*��A�:�CE&�^{-0C\F�S$P$HI+.(>��D�&)Uu&)/$(8CbU'F'*,+I-�/�3\i�9�& �f  �¦l�C�+.J6:�(>U ��S�:�C�R�XQ:G^{C�&8&@:6/$R�/$-0/T�BF�:6*E&8/c*���+I/�^{C�+I/$?�+I/$?CE&)F$H�:6(8&8MG&8/c*�^{-0CO*,9$&�/$-0/T��^{CE&)&vF$CE-�?0C,:�M l ��l#X +I7q:6HICE&8:�R�U Pa&)+I/$?�S�7E&8R«3 ¬Y%'VOXd:�^{CE&)&�:�/$R /$-0/T�F�:6*E&8/c*���+I/�^{C�+I/$?�+I/$?qCE&)F$H�:6(8&8MG&8/c*�^{-0C�*,9$&O/$-0/'��^{CE&8&�F$C�-0?0C,:6M %$%�VOXQ+I7�+I/sR$&)J�&8H.-0F$MG&8/c* P$S'* /$-�*�U0&>*CE&8:�R�U2^{-�C�S$7E&63i�9$&�CE&)7E&8:�CE(g9NHI+.*E&8CE:6*,S$C�&<+I7 ^{S�HIH�-6^«F$S�P$HI+.(>�BD6&)Uc�BP$:�7E&)R2:�S�*E9$&8/c*E+I(�:;*,+I-�/�F$CE-�*E-'()-0HI7)X]:�/$RG:�/q+IMGFQ-0Cb�

*g:6/]*<CE&8()&8/c*�R$&)MN-0/�7�*,CE:6*,+.-0/Z7�9$-KA�&)Ru*E9�:6*�7E&8C�+I-0S�7�:�S�*E9$&8/c*,+.(�:6*E+I-0/Z(�:�/$/�-�*�PQ& R$-0/$&\A�+.*,9�-0S�*<7�-0MG&^{-0C�M -6^WF$S$P$H.+I(>��D�&>UZ()C�UTF�*,- � 4¤�0� �3di�9�& � +��G&>�BV\&8H.HIMN:�/qF$S$P$H.+I(��BD�&>UZ()C�UTF�*E-0?0C,:6F$9$+I(L:�HI?�-0CE+5*,9$M ��¢c��+I7�/$-KA¨+I/2*E9$&�F$S$P�HI+I(LR$-0MN:�+I/�3 � ^{&)Az7E+IMGF$H.& 7E(g9$&)MN&)7�^{-0C�HI-0?�+I/v:�S'*,9$&)/]*E+I(8:6*,+.-0/�:�CE&\^{CE&8&)H.U2:KJ6:�+.H5�:�P$H.&�X<7�S$(g9 :�72%]����&)U -�/$&>��*,+IMG&�F�:�7�7�A"-0CER$7)3¨i�9$&�©snBi � *,9$&)/�:���&8C�Pa&)CE-07Z:�/$R "&8CED6&8H.&)U �% ��\/�+5= :�C�&2^{S$C�*E9$&8Cq&�=$:6MNF$H.&87�A�9$&)CE&u7E&8()S$CE+5*BU 9�:�7qPQ&8&8/�:�7E&8C�+I-0S�7G()-0/$()&8CE/«X�:�H.*E9$-0S$?�9 �f&)CEPQ&8C�-079�:�7L&>='Fa&)CE+.&8/$()&8R :NJ6:�CE+.&)*BUs-�^�7E&)(8S$C�+.*BU ��:KA�7)3�l �fl |ªldCE&)*�*BU ��-'-TR�ldC�+.J6:�()U�~\+.7LPQ&8()-0MN+./$?2MG-0CE&A�+IR�&87EF�CE&�:6R :�7@+.*OPQ&8(8-�MN&)7@7E&8:�MNH.&87�7EH.U &8M_Pa&)R$R$&8R�+./&>��MZ:6+IHd&8/cJT+IC�-0/$MG&8/c*,7)X�:�H.*E9$-0S$?09 9�:�7@9$:�R7E-�MN&\F$CE-0F�CE+I&>*g:�CbUqS$/$R$&)CEF$+./$/$+./$?0783�%T-0MN&�-�^�*E9$-07�& F$CE-TR$S$(>*,7"(�:�/v:6HI7E-OPa&\-0P�*,:�+I/$&)RZ()-0MNMG&8C�(8+I:�HIH5U*,9�CE-0S$?�9v-0CE?c:6/$+I[8:6*,+.-0/$7�*,9�:6*�F$CE-KJT+IR�&�-0Fa&)C,:6*E+I-0/$:�HQ:�/$RvMN:�+I/c*,&)/�:�/$()& 7ES�F$Fa-�C�*�X'7ES$(g9s:�7�l �fl§:6/$Ry�&8R�V\:6*L¬W+./]S'=a3�nB/�R$&8&)R�X«+5*\+.7\/�-�*L&)7E7�&8/c*,+I:�H#*E9�:6*\/$-0/$F�CE-0F$C�+I&>*g:�CbU�7E-�^t*BA�:�CE&OPa&O:�J6:�+IHI:�P$HI& ^{C�&8&�-�^(g9�:�C�?0&�X¡:6/$Rs()-0/$7�+IR$&)C,:�P$H.& J6:�HIS$&�(8:�/uPa&f:�R�R$&8RuPcU�(8-0MGMN&)CE()+�:�HQ&8/c*,&)CEF$C�+I7�&8783 � 9�:6*�+.7�+IMGFa-0Cb*g:�/c*+I7"*,9�:6*"*,9$&�7�-�^t*BA�:�CE&�PQ&�:�J6:�+IHI:�P$HI&�^{-0C�-0Fa&)/v7E()CES�*E+I/cU0X�:6P$HI&L*E-@PQ&�+IMGF$CE-KJ0&)R2-KJ0&)C<*,+IMG& :67�:@CE&)7ES$H5*-�^Q:�/�-�Fa&)/�(8-0H.H�:�PQ-0C,:;*,+.J�&�F$CE-T(8&)7E78X]:6/$Rq:�P$H.&"*,-�PQ&<7�S$P���&8(>*,&)RG*E- R$+I7b*,C�+IP$S�*E+I-0/$:�H](8-0/c*,C�-0HI7#*,- &)/$7ES�CE&+.*E7�+I/c*,&)?0CE+5*BU03

� &�/$&8&)R 7�+I?0/$+���(�:6/]*f+.MNF�CE-KJ0&)MN&)/]*E7�-0/�*,-TR�:�U ��7f7E-6^t*BA<:�C�&�XWPQ-�*,9pF$C�-0F$CE+.&)*,:�C�U�:�/$Rp-�*,9�&8C�A�+.7E&6X*,-�-KJ0&)CE(8-�MN&\M_UTCE+�:6RNC�+I7ED]7L|ª7�&8&�*,9$&\y�nb%'�O%G:�CE(g9�+.J0&)78X'9]*�*,F���m0m6(8:6*,H.&87�783�/$(8H}3�:�(63�S�D�m6y�+.7ED]7gm'X'-0Cd*,9$&�nBH5�HIS�7�*,CE:6*,+5J0&Oy�+.7ED]7 R$-T(8S�MN&)/]*8X«9c*E*EF���m0m;A�A�Af3�(87EH}3�7�CE+}3�()-0M2m;/$&8S$MN:�/$/�m0~>3 � 9$&8/�()-0MGMN&)CE(8+I:�H�7�UT7b*,&8MG7:�C�&</$-�* :�R$&8x]S�:;*,&8H5U_C�-0P$S$7b*�X0A"&�M@S$7b* (8-�/$7E+.R$&8C 9�-¤A§7E-�S$/$R�-0FQ&8/'��Pa-�=_(8-0MGFQ-0/$&8/c*E7 MN+.?09c*�PQ&<()-0Mq�FQ-07E&)RO+./]*E-�R$&8MG-0/$7b*,CE:�P$H.U\CE-�P$S$7�*#7bU'7b*,&)MN7)3�i�9$+.7�CE&8x]S$+.CE&)7Y:6/�+./c*,&8C�/�:6*E+I-0/�:6H6()-0HIHI:�Pa-�C,:6*E+.J0&YF$CE-T(8&)7E7)X-0FQ&8/'��&8/$R�&8R�XQHI-0/�?6��*E&8CEMuX�^ª:�C��B7�+I?09c*,&)R�X¡7E-0MG&)A�9$:6*\:�H.*ECES$+.7�*,+.(�X$+./$(8C�&8MG&8/c*g:6H�X¡:�/$RuA�+.*E9�R$+5J0&8C�7E&OF�:�Cb�*,+.(8+.F�:�/c*,7�^{CE-0M R$+5`«&)CE&)/]*�R$+I7�(8+.F$HI+./$&87�:�/$RZF�:�7�*�&>='FQ&8CE+.&8/$()&87)3"n�*�:�HI7�-_C�&8x]S$+IC�&87<7�&8C�+I-0S$7�:6*E*E&8/c*,+.-0/N*E-*,9�&�C�&�:�7�-0/$7�A�9cU�(8-0MGFa-�7E+.*E+I-0/Z9�:�7�Pa&)&8/u7E-GCE+I7�DcUv+I/v*,9�&�F$:�7�*_|}:67�R�+I7E()S$7E7�&8R�+./v*,9$&fR$&)P�:6*,& � 4 � ��/$-�*E&8R�:;*\*E9$&_&)/$R�-�^�%'&)()*E+I-0/ �'3�£0~>3\lY&8CbJ6:�7E+5J0&�:�R�9$&8C�&8/$()&_*,-N?0-'-TR�R�&)J0&)HI-0F�MN&)/]*LF$C,:6()*,+.(8&O+I7\:�HI7�-/$&)(8&87�7,:�CbUw|{A�9�+I(g9�7ES�?0?0&87b*,7@PQ&)*�*,&)C_*,&8:�(g9$+I/�?�:�7_A"&8H.Ht~>3si�9$&2F$C�-'()&87�7�/$&8&)R$7�7E-0MG&ZR�+I7E()+IF$H.+I/$&6X�+./

� �

Page 105: Practical Architectures for Survivable Systems and Networks (Phase

-0C�R$&8Cd*,-�:�J0-�+IRGC,:�MGF�:�/c*�F$C�-0HI+5^{&8C,:;*,+I-�/_-�^a+I/$()-0MGF�:6*,+.P$HI&�J6:�CE+I:�/c*,783 e¡-�C�*,S�/�:6*,&)H.U�X�*,9$&)CE&\:�CE&�:6HICE&8:�R�U7E-�MN&LJ�&8CbUv7ES$P�7�*g:6/]*E+.J�&�&)`a-0C�*E7<*,-�R$&>J0&8H.-0F�X$MN:�+./]*,:�+I/«X':6/$Rv7ES$F�Fa-0Cb*�-0FQ&8/'��Pa-�=Z7E-�^t*BA�:�CE&�7bUT7�*,&)MN7)XA�+.*E9�7E+.?0/$+���(�:�/c*\MN-�MN&)/]*ES$Mu3�n�^d*E9$-07�&_&)`a-0Cb*,7L(8:�/�7�S$(8()&8&8Rj+I/sF$CE-TR$S$()+I/$?NR$&8MG-0/$7b*,CE:�P$H.U�C�-0P$S$7b*7�UT7b*,&8MG78X�*E9$&)UvA�+.HIH�:6HI7E-qF$C�-KJ'+.R$&f:�/u+I/$()&8/c*,+5J0&�^{-0C�PQ&)*�*,&8C�()-0MNMG&8C�(8+I:�H«7bU'7b*,&)MN7)3¥LJ0&)C,:�H.H�X\A"&j/$&8&)Rz*,&)(g9$/$+.xTS�&87s*E9�:6*s:�S$?�MN&)/]*�*E9$&pCE-0P$S�7�*,/�&87E7�-�^_H.&87�7sC�-0P$S$7b*s()-0MGFa-0/�&8/c*,7)X

F$S$P�HI+I(��BD6&)U_:�S�*,9�&8/c*,+.(�:6*E+I-0/�X6(8CbU'F'*,-0?0CE:�F$9$+.(�+./]*E&8?0C�+.*BU�7E&8:�HI7)X0?0-T-'RO(8CbU'F'*,-0?0CE:�F$9cU0X0*ECES$7b*BA�-�C�*,9cU�R�+I7b�*,C�+IP$S'*,+I-�/ F�:;*,9$7)X�:�/$Rh*ECES$7b*BA�-0Cb*,9cUR�&87E()CE+.F�*,+.-0/$7_-6^�*,9$&NF$CE-KJ0&)/�:�/$()&v-�^�+I/�R$+.JT+IR�S�:�Hd(8-�MNFQ-0/$&)/]*E7:�/$R A�9$-�9�:�7�MG-'R$+���&8Rj*,9$&)Ms3 � &Z/$&)&8RR�&)*g:6+IHI&)Rh&>J�:6HIS�:6*E+I-0/�7�-6^�(8-0MGFQ-0/$&8/c*E7@:�/$R *,9$&N&)`a&8()*E7-�^<*E9$&8+.C_()-0MNFQ-07�+.*,+.-0/§|{A�+5*,9+./]*E&8C�&87�*E+I/$?s-0F$FQ-0C�*ES$/$+5*,+I&)7�^{-�C�^{-0C�MZ:6H�MG&)*E9$-TR$7g~�3�©�:6/]U F$C�-0P$HI&)MN7M@S$7b*�PQ&v-¤J�&8C�(8-0MG&�X�+I/�(8HIS�R$+I/$?sR$&)^{&)/$7E&)7G:�?c:�+./$7�*_iYC�-��E:�/ 9$-0C�7E&87�9�+IR$R$&)/�+I/�7bU'7b*,&)MN7)X�()-0MGF$+IH.&8CE7:�/$Rh&)J6:�HIS$:6*,+.-0/ *E-'-0H.78XY+I/h9$:�CER�A�:�C�&�Xd7E-�S$CE()&2(8-TR$&�X�:6/$R-0P���&)()*�()-'R�& j&87�Fa&)(8+I:�HIH5U�A�9$&8/�FQ&8C�Fa&��*,CE:6*,&)R@PcU_+./$7E+.R$&8C�783 � &</�&8&8R�F�CE-KJT+IR$&)CE7�A�9$-�?�+.J0&"CE&8:�H'7�S$F$FQ-0C�*��0A<:6CEC,:6/]*E+I&)7 -0/@7bU'7b*,&)MN7 *E-'R�:�UO:�C�&MG-07�*EH.UqJ0&)C�UZA"&�:6DQ3 � & /$&)&8R�7E&)CE+I-�S$7<+I/�(8&8/c*E+.J0&)7�+I/$()HIS$R�+I/$?f^{S$/$R$+./$?_^{-0C�CE-0P$S�7�*�-0FQ&8/T�BPQ-K=Z&)`a-0Cb*,783� &87�F$+.*E&@:�H.H�*,9$&_(g9�:�HIH.&8/$?�&878X¡*,9�&_FQ-�*,&)/]*E+�:�HWPQ&8/$& �$*,7L-�^�CE-0P�S$7�*L-0Fa&)/'�BPQ-�=s7E-�^t*BA�:�CE&@:�CE&fA�-�C�*,9cUs-�^(8-�/$7E+.R$&8CE:�P$HI&�()-0HIHI:�PQ-0C,:6*E+.J�&L&)`a-0Cb*�3ldH�:�/�7�^{-�C�*E9$&_()-0HIHI:�PQ-0C,:6*E+.J�& CE&)7E&�:6CE(g9�:�/�R�R$&>J0&8H.-0F$MG&8/c* -6^�*,C�S$7�*BA"-0Cb*,9cU�7�S$C�JT+5J�:6P$HI&N|ª&63�?�3.XQCE-6�

P$S$7b*�XY7E&8()S$CE&6X CE&)HI+I:�P$HI&�~\+I/c*E&8CE-�Fa&)C,:�P$H.&q/$-0/$F$C�-0F$C�+I&)*,:�C�Up-�Fa&)/'�BPQ-�=j7E-�^t*BA�:�CE&G(8-�MNFQ-0/$&)/]*E7@:�C�&qPa&��?0+./$/$+I/�?h*,- ?0&)CEMG+I/�:6*E&�3 � &pM@S$7b*�7E&)&8D :�/ -0FQ&8/ F$C�-'()&87E7v*E9�:6*�&8/�(8-0S$CE:�?0&)7u*E9$&�R$&)J�&8H.-0F$MG&8/c*-�^L7�UT7�*E&8MG7Z:�/�R§()-0MNFQ-0/$&)/c*,7N:�R$R$C�&87E7�+I/$?p*,9�&s&)7E7E&)/c*,+�:6H�F�CE-0P$H.&8MG7�R$& �$/$&8R§+I/ *,9$+.7�CE&8FQ-0Cb*�X<:6/$RA�9$+.(g9NMG+I?09c*�+./$+.*E+�:�H.H.U�PQ&�(�:�H.HI&8RGldCE&>*E*BU ��-'-TRN%'S$CbJ'+5J6:�P$+IH.+.*BUZ|}l ��%$~>3ci�9�&\+./]*E&8/c*�+I7 *E9�:6*�Xc*E9$CE-0S�?09HI-�/$?6��*E&8C�M -0Fa&)/�(8-0H.H�:�PQ-0CE:6*,+5J0&q&)`a-0C�*E7@+I/cJ�-0H.JT+I/�?�CE&)7E&�:6CE(g9 :�/$R�R$&>J0&)HI-0F$MG&8/c*�()-0MGM@S$/$+5*,+I&)7_:6/$RS$/$+5J0&)CE7E+5*,+.&878XYl �O%�(8-�S$HIR ?0C,:�R�S�:�HIH5U�&>J0-0H5J0&N+I/c*,- ��&8CbU �f-T-'R %'S�C�JT+.J6:�P$+.HI+5*BU�| � �O%$~�3 � *O*E9$&qMN-6�MG&8/c*�X � ��%u7E&)&8MG7\H.+ID6&O:GR$CE&8:�MuX�P$S�*\+.*�7E&)&8MG7�*E-ZPQ&�^{&8:�7E+.P$HI&�+5^dl �O%�+I7�7ES�+.*g:6P$H.UvMG-�*E+.J6:6*,&)R�3�n�*:�H.7E-�7E&8&)MN7":�P$7�-0HIS'*,&8H5U�&87�7E&)/]*E+�:�H�*E-�*E9$&�^{S'*,S$C�&\-�^«9$+I?�9$H.U_7ES$CbJ'+5J6:�P$HI&�7bU'7b*,&)MN7)X$:�/$RN7E9$-�S$HIRGPa&�A"&8HIHA"-0C�*E9uA�9�:;*,&)J�&8C�&)`a-0C�*�+5*�CE&)xTS�+ICE&)783� R$+.7E(8S�7E7E+.-0/ ?0CE-0S�F ^{-0C@*E9$&�&8/$()-0S$CE:�?0&8MG&8/c*N-�^\&)`a-0C�*E7q*E- F�CE-TR$S$(8&�C�-0P$S$7b*N/�-0/$F$C�-0F$CE+.&)*,:�C�U

-0FQ&8/'��Pa-�=u7�-�^t*BA<:6CE&Z|{A�9$&>*,9$&)C �,¥ FQ&8/'��%'-0S$C�(8&��N-0C �Ee�CE&)&��]~<*,9�:;*\n"^{-0CEMG&8Ru-0/j404_ �-KJ0&8M_Pa&)C_4K¢0¢�£9�:�7�9�:6Rs7�-0MN&�+./$7E+.?09c*E^{S$H«R$+I7�(8S$7�7E+I-�/$783\|ªi#- ��-0+I/�X'7E&)/$R�&��BMN:�+IH¡*,-��������������� ������������������������������� �� ��"! A�+5*,9G*,9$&\-0/$&>��HI+./$&�(8-0/c*,&)/c* �"��#$�� ����%#�� � -�C �"��#&�� ����%#��� U0-0S$C\:�R$R�CE&87�7 Y+.^#U0-0S�C�R�&87E+.CE&)R�:�R$R�CE&87�7L+.7�R$+.`a&8C�&8/c*\^{C�-0M�U�-0S$C(' ���"!*) :�R$R$C�&87�7��«©�: ��-0C�R$-0MG-qA�+.HIH:�()(8&8F'*\()-0/c*,C�+IP$S�*E+I-0/�7<^{-0C<*,9$&f?0C�-0S$Fu-0/$H5UZ^{CE-�M U0-�S$C�7EFQ&8(8+���&8R ���+) :�R$R$C�&87E7)3�~� /�+I/c*,&)CE&87b*,+./$?R$+.7E(8S�7E7E+.-0/�-�^LA�9$&)*E9$&8Cv-0FQ&8/T�BPQ-K=§7�-�^t*BA<:6CE&�(8:�/r+I/$()CE&8:�7E&s7E&8()S$CE+5*BU�+.7N^{-0S�/$R

+I/*E9$&�Fa-�7E+.*E+I-0/hF�:�FQ&8CE7�^{-0C@:pF$:�/$&8H�7�&87�7E+I-�/�:6*_*,9$&s���0����n ����� %]U'MGFQ-07E+.S$M -0/§%'&)(8S$C�+.*BU :6/$RldCE+5J�:6()U0XQA�+.*E9�F�:�FQ&8C�7 PcUp%T*E&)J0&q¬�+.F$/$&8C�� 4�£ ��}X �f:�C�U�©s( �fCE:KA � 4K¢0¢ }X� �&8S$MN:�/$/ ��� ��£ �X«:�/$Rpe�CE&)R%'(g9$/�&8+IR�&8C�� ��1�1 }3 � /_:�R�R$+.*E+I-0/�:6H�F�:�/�&8HcFQ-07E+5*,+I-�/�F�:�FQ&8C�A�CE+5*E*,&)/fP]U "CE+�:6/ � +.*E*E&8/�X�k<:�C�H]¬#:6/$R�A"&89$C)X:�/$R�©s+I(g9$:�&8H�k<:�HI-KU0:�/$/$+.R$&87L:�CEC�+.J0&)Rs*E-'-NH�:6*E&f^{-�C\+./$(8H.S$7E+.-0/s+./u*E9$&_F�CE-T(8&8&)R$+I/�?078XQP$S�*L+I7�:�J�:6+IH�:6P$HI&-0/'��HI+./$&��Y9]*�*,F���m0m;A�A�Af3�(87�H�3�7EC�+�3�(8-0MZm6/$&)S$MZ:6/$/¡m;A�+5*E*,&)/�3�F$783 � H.7E-�-0/v*,9�&�F�:�/$&)H�A<:�7 � CE+.(�y�:KUTMG-0/$R�XA�9$-@/�-�*,&)RZ*,9�:;*"*E9$&L()-0M@P$+./$&8RZ^{-�CE(8&)7�-�^«*,9$&\-0Fa&)/'�BPQ-�=NMN-KJ0&)MN&)/c*<+I/cJ�-0H.J�&����0���_:�(>*,+.J�&LF$C�-���&8(>*,7)X� ���'X��0����F�:6C�*,+.(8+.F�:�/c*,7)X�:�/�R�4 ����X��0�0�f9�:�C�R'�B()-0CE&\R$&)J�&8H.-0Fa&)CE7)3di�9�:6*<C�&8F$C�&87�&8/c*,7�:�J�&8CbUZ()-0/$7E+.R$&8CE:�P$H.&FQ-�*,&)/]*E+�:�Ha^{-0CE()&f*E-qPa&fMG-0P$+IH.+I[)&8R �� ^{S$/�R�:�MG&8/c*g:�H«R$+I(g9$-6*,-0M_UN7E&)&8MG7�*,-�&>='+.7�*�PQ&)*BA"&8&8/s7�UT7�*E&8MG7�*,9�:6*�M_S$7�*�PQ&�7,:;^{&f:�/$R�CE&)HI+�:6P$HI&

-0/p-0/$&�9$:�/$R�X#:�/$Rp7�&8(8S�CE&G-0/�*,9$&q-�*E9$&8C)3@nB/j*E9$&@^{-0C�MN&)C (�:�7�&�X#-0FQ&8/'��Pa-�=�7�-�^t*BA�:�CE&q+I7�&�=T*,CE&)MN&)H.UR$&)7E+ICE:�P$H.&�*E-@Fa&)CEMG+.*�&>=T*E&8/$7�+.J0&f:6/�:�H.UT7�+I783�nB/Z*,9$&LH�:6*�*,&8C�(�:67E&�XT*,9$&\+I/$?�C,:�+./$&8RNF$CE&)R$+IH.&8()*E+I-0/q*,&)/$R$7�*E-F$C�-0MN-6*,&f7E&)(8S$C�+.*BU�PcUu-0P$7E()S$CE+5*BU � A�9$&)*E9$&8C\-0C\/�-�*�+.*�+I7�/$&)(8&87�7,:�CbU03�V\+.?09$H5U27ES�C�JT+.J6:�P$H.&fMN+.7E7E+.-0/'�

� �

Page 106: Practical Architectures for Survivable Systems and Networks (Phase

(8C�+.*E+I(�:6HQ7bUT7�*,&)MN7�(8HI&8:�CEH5UqR$&87�&8CbJ0&�?0C�&�:6*E&8C�7�(8C�S�*,+./]UG*,9$:�/v:6`a-0CER�&8R2PcUN(8HI-�7E&8RT�B7E-�S$CE()& 7E-�^t*BA�:�C�&�X$P$S'*FQ&8CE9$:�F$7fMZ:�U�/$-�*fMG&8CE+5*�(8-�MNF$H.&)*E&8H.Us-0FQ&8/'��Pa-�=�7E-�^t*BA�:�CE&qA�9$&)CE&�*,9$&G:6*�*g:�(gD6&8C�7O()HI&�:6CEH.Us9�:�J0&q*,9�&:�R�J6:�/c*,:�?0&�3dnBR�&�:�H.H.U0X�+.^Y:�7�UT7�*E&8M�+I7�7E&8()S$CE&6X¡+.*�7�9$-0S$H.RuPQ&fFa-�7E7E+.P$HI&\^{-0C<*,9$&�R�&87E+.?0/u:�/$Ru+IMGF$HI&)MN&)/'�*g:;*,+I-�/Z*,-@PQ&f:�J6:�+IHI:�P$HI&63�V�-KA�&>J0&8C)X¡MZ:�/cUN-�^W*,-TR�:�U ��7<7bUT7�*,&)MN7�:�C�& 7E-@^ª:6C�^{CE-0M :�R�&8x]S�:6*E& *,9�:6*�*,9$+.7+IR�&�:�Ha7E&8&)MN7�S�/�:6*E*,:�+I/$:�P$HI&63 i�9]S$78X$*E9$+I7�R�+I(g9$-�*E-0M_UNCE&)MZ:�+./$7"J�&8CbUvR$+��G()S$H.*<*E-�CE&)7E-0H5J0&f:�R$&)x]S�:6*,&)H.U�3

����������� ��� 1 ( ��� ��� + + ( �.-0/ �%1 � �� ���r- � " �B+ � � -e1� �

i�9$+.727E&)()*,+.-0/r7ES�MNMN:�CE+.[8&)7Z7E-�MN&�-6^�*,9$&�MG-07�*ZCE&)HI&)J6:�/c*vF$:�Fa&)CE7Z^{C�-0M :CE&8()&8/c*u  � i�¥ (8-�/�^{&8C��&8/�(8& ������¢��-�/�k�-�MNMG&8C�(8+�:6H<¥L`¡�Bi�9$&��b%'9$&)H.^\ldCE-TR$S$(>*,7�+I/ � &>^{&8/$()& � F$F$H.+I(8:6*,+.-0/$78�Gi�9$&�y�S�*,9�HI&87�7ldS$CE7�S$+.*<-�^�k�¥�i�%p|{+I/v:�R�R$+.*E+I-0/G*,-@*,9�& 7EH.+IR$&)7<F$CE&)7E&)/]*E&8RuPcUv \&)S$MN:�/$/ ��� �0� }X�A�9$+.(g9�:�CE&L+I/$()HIS$R$&)R+I/O*,9$&<F�CE-T(8&8&)R$+I/�?07�-�^�*E9�:6*d()-0/�^{&)CE&8/�(8&�X]:6/$R@A�9$-07�&�(8-0/$()HIS$7�+I-0/@:�CE&"7ES$MGMZ:6CE+I[)&8R_:6* *,9�&�PQ&8?0+./$/$+I/�?-�^#*,9$+.7�7E&)()*,+.-0/¡~�3

2 ldC�-�^{&87�7E-0CW \:�/$()U�¬W&>J0&)7E-0/�Xc©snBi � &8CE-�/�:�S�*E+I(87W:6/$R � 7�*ECE-0/$:�S�*,+.(87 � &)F�:�C�*EMN&)/c*�� �\7�+I/$?\k�¥ i�%k�-�MNFQ-0/$&)/]*E7d+I/G%�:;^{&)*BUc�bk�C�+.*,+.(�:�H$%TUT7�*E&8MG7�� 4¤�;1��3 ��nB/�MZ:6/]U_(�:�7�&87)XTS�7E+I/�?_k�¥ i�%@(8-�MNFQ-0/$&)/]*E7+./@7,:;^{&)*BUc�B()CE+.*E+I(8:�H�7bU'7b*,&)MN7 A�+5*,9q:�()(8&8F'*g:�P$H.&�CE+.7EDfA�+IHIHT7E+.MNF�H.U�Pa&�+I/�^{&8:�7E+.P$HI&63YnB/@*E9$&87�&�(8:�7E&)78X]+.*A�+.HIH�PQ&�(g9$&�:�FQ&8CL:�/$Rs7,:6^{&)C�*E-NF$C�-KJ'+.R$&_7�Fa&)(8+I:�H5��F$S$CEFQ-07�&�7�-�^t*BA�:�CE& � S�7E+I/�?2k�¥ i�%�:�MG-0S$/c*E7*E- ^ª:�H.7E&s&8(8-�/$-0M_U *,9�:;*ZA�+IH.H�(8-07b*2MG-0CE&s+I/§*E9$&�&)/$R�3¨i�9$&)CE&�:6CE&�X�9$-KA"&)J�&8C8X\7E+5*,S�:6*E+I-0/�7N+./A�9�+I(g9wk�¥ i�%�(8-0MGFQ-0/$&8/c*E72(�:�/rPQ&�:�7�7ES$C�&8Rr*,-h9�:�J0&p:�R$&)x]S�:6*,&�7bUT7�*,&)M 7E:6^{&)*BU�3¦nB/�*E9$&87�&(8:�7E&)78X &)+.*E9$&8C�*,9$&G7�UT7�*E&8M R$&87�+I?0/ M@S$7�*@:�HIH.-KA F$C�-�*,&)()*,+.-0/:6?c:�+I/�7�*O:�/cUhFQ-07�7E+IP�HI&q9�:�[8:�CER$-�S$77�-�^t*BA�:�CE&qPQ&89�:�JT+I-0Cf-0Cf:�(8-�MNF$H.&)*E&�P$H�:�(gD]PQ-�=pPa&)9�:�JT+I-0Cf7EFQ&8()+���(8:6*,+.-0/pM@S$7b*OPQ&qF$CE-KJT+IR�&8RjP]U*E9$&uF$CE-TR$S$()&8CG-�^L*E9�:6*N(8-0MGFa-�/$&8/c*G+I/ -0CER�&8Cq*,-jFa&)C�^{-0C�M :j7bU'7b*,&)M 9�:6[�:�C�R�:�/�:6H.UT7E+.783�e�-0C()-0MGF$HI&�=�7�-�^t*BA�:�CE&6X�7EFQ&8()+�:�H#7�UT7�*E&8M 9$:�[�:�C�R�:�/�:6H.UT7E+.7\*,&)(g9$/$+.xTS�&87�:�/$R�*E-'-�HI7�MZ:�UsPa&O/$&8&)R$&8R*E-G:�7E7�+I7�*�*E9$&f7�UT7�*E&8M�&8/�?0+I/$&)&8C�+I/v*E9$+I7<*,:�7ED¡3 �

2 n�:6/ � 9$+5*,&6X �L� � &)^{&8/�(8& � J6:�H.S�:6*,+.-0/�:�/$R_y�&)7E&�:6CE(g9 � ?0&8/$(>UZ| � � y � ~>� � C,:�F�F$+I/$?�*,9�&<k�¥ i�%� +.HI&)MNMN: ���0¢0��}3 �,%�:;^{&)*BU (8C�+.*,+.(�:�H�|}%$k�~�7E-�^t*BA�:�CE&s(�:�/�/$-�*NPa&sF$CE-KJT+IR$&)R§^{C�-0M MZ:6+I/$7b*,CE&8:�Mk�¥ i�%a3¡V�-KA�&>J0&8C)XaMG-0C�& CE&)HI+�:6P$HI& 7�-�^t*BA�:�CE&f(�:6/sPQ&�MZ:6R$&�S$7E+./$?N%$kwF�CE+I/�(8+IF�HI&87)3<353.3 � C�(g9$+.*E&8(��*ES$CE&�MN:�/$R$:6*,&)7�R�-G/�-�*\:�R$R$C�&87E7�*,9�&�F�CE-0P$H.&8MG7�-�^YS$7E+./$?Nk�¥�i�%�+I/vMG+IH.+.*g:6C�UG7�UT7�*E&8MG783 �

2  �+I("lY&)&8HI+./$?\:�/$R�y�+I(g9�:6CER_iY:�UTHI-0C)X �L� � &>^{&8/$()& � J6:�HIS$:6*,+.-0/_:6/$R�y�&87E&8:�CE(g9 � ?0&8/�()UZ| � � y � ~>�%]*g:�/$R$:�CER$7 � ©uU]*,9$7)X � &)HIS$7�+I-0/$7�:�/�R¥ F$FQ-0C�*ES$/$+5*,+I&)7 ����¢61 }3 �)353.3G*,9$&GR$&)^{&)/$(8&N(8-0MGM@S$/�+.*BU7�9$-0S$H.R_()-0/$7E+.R$&8CWA�9$&>*,9$&)CY*,9�&�H�:;*,&87b*�R�&)J0&)HI-0F�MN&)/]*E7�+./OnB/c*,&)CE/$&>*�%T*,:�/$R�:�C�R$7 :6/$R�¥ FQ&8/�%T-0S$CE()&-6`«&)C�:�/N-0F$FQ-0C�*ES$/$+5*BU�*,-_(8:�F�*ES$CE&�*,9$&\Pa&)/$& ��*,7<-�^�¥ Fa&)/�%TUT7�*E&8MG7"A�9$+.(g9Z*,9$& �L �n � +./$R$S$7b*,C�U7�x]S�:�/$R$&)CE&)R�+I/v*E9$&q4K¢0£0��7)3 �

2 � :6MN&)7 <:6CEP�:�C�&8H.HI-�:�/$R � :�H5*,&)CO�f:�7�+�:�/«X �L% � C�M_U k � k�¥f© � ��/$+.*E&8R%T*g:6*E&87 � CEMOU k�-0Mq�MG&8C�(8+I:�H�¥L`¡�Bi�9$&��b%'9$&)H.^ |�k�¥ i�%$~ � ='Fa&)CE+I&)/$(8&6� i�9$&\ldCE-0MG+I7�&87�:�/$RGy�&�:�H.+.*E+I&87 ����£ �3 �)3.353d:�R�-0F�*�X:6R�:�F�*8X$R$&)J�&8H.-0FsF�9$+IH.-07E-0F�9]U�3 � �)353.3�:�/cUvR�&8(8+.7E+.-0/v*,-TR�:�U�3.353dMN:KU2Pa&�R$+5`«&)CE&)/]*�*E-0MN-�CECE-KAf3 �

2 ©s:�CED�� +IR�?0&8C�:6/$R � -09$/ � &�:�/«X� L:6*E+I-0/$:�H_y�&87�&�:�C�(g9 k�-0S�/$(8+.H@-�^Zk<:�/�:�R$:��o©�:�+./c*g:�+./$+I/$?k�¥ i�%]� <:�7�&8Ro%TUT7b*,&8MG7 � �c�6¢ �3 � � H5*,9$-0S�?09z()-0MGFa-0/�&8/c*���P�:�7E&)R�7�-�^t*BA<:6CE&h7bUT7�*,&)MN7sF$CE-KJT+IR�&MN:�/cUv:6R�J6:�/c*g:�?0&)78X�R$&)7E+.?0/$&8C�7�:�/$R�S$7E&)CE7�M@S$7b*�7�*,+.HIHa&>='Fa&)()*�*,9$:6*�*,9$&fMN: ��-0C�+.*BUN-�^Y*E9$&�HI+5^{&8(>U]�()HI& ()-07�*�A�+.HIHQPa&L+I/$()S$CEC�&8Ru:6^t*,&)C�*,9�&�+I/$+5*,+�:6H�R$&8F$H.-KU'MG&8/c*�-�^W*E9$&�7�UT7�*E&8Mu3�y�&)R$S$(8+./$?@*,9�+I7<()-07�*8X:6/$Rp&�:�7�+I/$?2*E9$&qMZ:�+./c*,&8/$:�/$(8&@:�/$RpMZ:6/�:�?0&)MN&)/]*f&>`«-�C�*�X�C�&8x]S$+.CE&87�R�&87E+.?0/$&)CE7�:�/$Rj:�C�(g9$+.*E&8()*E7

� �

Page 107: Practical Architectures for Survivable Systems and Networks (Phase

*E-Z()-0/$7E+.R$&8C\*,9$&OFa-07b*���R$&8F$H.-KU'MG&8/c* :�()*E+.JT+.*E+I&87�R$S$C�+I/$?G*,9$&_&�:�C�HI+I&)7�*\7�*,:�?0&87L-�^�7E-�^t*BA�:�C�&@R$&)J�&8H �-�F$MN&)/c*�3 �U�+.R$&8/c*,+5^tUT+I/$?j*,9$&�:6()*,+5JT+.*,+.&87q*,9�:;*2MN:�+I/c*,&)/�:�/$()&�:�/�R�MZ:6/�:�?0&)MN&)/]*ZFa&)CE7�-0/$/$&)HFQ&8Cb^{-0CEM�*E-27ES$F�Fa-0Cb*�(8-�MNFQ-0/$&)/]*b�BP�:67E&8R�7bUT7�*,&)MN7)X�:�/$R�S�7E+I/�?v:ZR$&)7E+I?�/�*,9�:;* 7ES�F$Fa-�C�*,7 *E9$&87�&:6()*,+5JT+.*,+.&87)X�7�UT7b*,&8MG7�(�:�/uPa&�MN:�R$&fMG-0CE&L(8-07b*��B&>`«&)()*E+.J0&63 �

2 %TS$7,:�/�/$& � :�/c*,7�(g9�X"n � � M_P�VOX �f&)CEMN:�/cUa�Zy�+.7ED]7@PcU ��7E+I/�?pk�¥ i�% ldCE-TR$S$(>*,7q:�/�R k�-0Mq�MG&8C�(8+I:�H$nbk�iw%'&)C�JT+I()&87 � 4�1�4��3 � � ()(8&8F'*,+I/�?O*,9$:6*�*,9$&�S$7E&�-�^�k�¥�i�%GF$CE-TR$S$(>*,7":�/$RZ()-0MGMN&)CE(8+I:�H7�&8CbJ'+.(8&)7ZA�+IH.H�(8-0/c*,+./]S$-0S$7�H.U§+I/$()CE&�:67E&�+./§*E9$&�MG+IH.+.*g:6C�U&)/cJ'+.CE-0/�MN&)/]*8X<*,9$&s-0PcJT+I-0S$7ZPa&)/$& �$*E79$:KJ�&L*,-OPa&LHI&)J�&8H.HI&8RGA�+.*E9Z/$-�*�x]S$+.*E& :�7"-0PcJ'+.-0S$7<C�+I7�DT7"-0/2-0/�&L9�:�/�Rv:�/$R�X'-0/Z*E9$&L-�*E9$&8C�9�:�/$R�XA�+5*,9v*,9�&�FQ-07�7E+IP�+IHI+5*,+.&87":KJ6:�+.H�:�P�HI& :6/$RsR�S�*,+.&87�S$/�:�J0-�+IR�:�P�HI& *,-G:�(>*,+5J0&8H5UvMN:�/�:�?0&\*,9$&)7E&�CE+I7�D]783 �

2 y�-0PQ&8Cb*�k�9�:�C�Fa&)/c*,+I&)Cd:�/$RG©s:�CE+./�%�:�H.-0+I7)X � &>^{&8/$()&�y�&)7E&8:�CE(g9 � 7�*g:6P$HI+.7E9$MG&8/c* ��:6HI(�:6C�*,+.&8C)X � S$&��PQ&8(6X�k<:�/�:�R$:�� � &)*,&)()*E+I-0/-6^\©�:�HI+.(8+.-0S$7_k�-'R$&Z+I/ k�¥ i�%�%'-�^t*BA�:�C�&vP]Uk�&8Cb*,+5^tU'+./$?pk�-0MGF$+.H5�&)CE7 ������}3�i�9$&8+.Cf:�F$F$C�-c:�(g9pCE&)xTS�+ICE&)7f:2(8&)C�*,+5^tUT+I/$?2()-0MGF$+IH.&8C\*E9�:6*�&)/�^{-0C�(8&87�:Z^{-0C�MZ:6HY7�&8(8S�CE+.*BU7�Fa&)(8+���(�:6*E+I-0/h:�/$R*BUTFQ&v:�/$/$-6*g:6*E+I-0/$7)3sn�*_+I7OP�:�7E&)R�-0/ ��CE&)?p©s-0C�+I7E7�&)*�* ��7@i�UTFQ&8R � 7�7E&)M@P$H.U¬W:�/�?0S�:�?0& |ªi � ¬#~�&)`a-0Cb*d:6*�k�-�CE/$&)HIH�3#n�*d-�^Q()-0S$CE7�&�CE&)xTS�+ICE&)7�:�(8()&87�7 *,- *,9�&�k�¥�i�%_7�-0S$C�(8&�(8-TR$&�3| � 7E&8()-0/$RsF�:�FQ&8C�P]Uv*E9$&87�&_:6S�*,9$-�CE7 � � � ��W&>=�:�MG+I/�&87�R�UT/�:�MG+I(fR$&>*,&8(>*,+.-0/uA�9�&8/�7�-0S$C�(8&_()-'R�&+.7�/$-�*�:�J6:�+IHI:�P$H.&�3�~

2 y�-0PQ&8Cb*_y�-KA�HI+./$?07E-�/�X � &)^{&8/�(8& � J6:�H.S�:6*,+.-0/j:�/$Rhy�&)7E&�:6CE(g9 � ?0&8/$(>U�| � � y � ~>�Wi�9$&2k�-0/cJ0&8C��?�&8/$()&u-6^�©s+.HI+5*g:�CbUj:�/$R�k�+.JT+IH � F$F$C�-c:�(g9$&)7G*E-pnB/�^{-0CEMN:6*E+I-0/ %T&8(8S�CE+.*BU � �c�����3 ��i�9$&�9$+I?�9$&87b*()H�:�7�7E+���&8R�+./�^{-0CEMN:6*E+I-0/ CE&8x]S$+.CE&)R +./�R$&)^{&)/$(8&�9�:67G/�-�(8-0S$/c*E&8CEF$:�C�*E7G+./*,9$&v()+.JT+IH"7E&)()*,-�CN:6/$R*E9$&8C�&�+I7�S$/�HI+ID6&8H5Us*E-uPQ&q:�/cUp:�H5*,&)CE/�:6*E+.J�&_*,-vC�&87�*ECE+.()*,+./$?v7ES�(g9h+I/'^{-0CEMN:6*,+.-0/s*E-vF�:�FQ&8C�-0C�+.7E-6�HI:6*,&)R�X$F$9cUT7E+.(�:�H.H.Uc�BF�CE-�*E&8()*E&8R�7�UT7b*,&8MG783 �

2  �-0CEMN:�/Z%'(g9$/$&)+IR$&>A�+I/$R«X$ L:�J6:�HalY-07b*,?0CE:�R$S�:;*,&�%T(g9$-'-�H�X'©s-0/c*,&)CE&>Ua��i�9$&Ly�S'*,9$H.&87E7�ldS$CE7�S$+.*"-�^*E9$&�iYC�S�*,9O:�PQ-0S�*Yk�¥ i�% � ��10� �3 ��i�9$&�R$&)(8+.7E+I-�/f*E-�&8MGF$HI-KUfk�¥ i�%f-0/fMN+.7E7E+.-0/�(8C�+.*E+I(�:6H�7�UT7b*,&8MG77�9$-0S$H.RN/�-�*�PQ&LP$:�7E&)R2-0/ZR�&)J0&)HI-0F�MN&)/]*"(8-�7�*�:6HI-0/$&63 y�:6*,9�&8C8XT(8-�7�*,7"7E9$-�S$HIRNPa&\&)J6:�HIS$:6*,&)RN-0/Z:*E-�*g:6HcHI+.^{&)()UT(8H.&�P�:�7E+.7#:�/$R � CE&)HI+I:�P$+IH.+.*BU�X�MZ:6+I/c*g:�+./�:�P$+.HI+5*BU0XK:�/�R@:�J6:�+IHI:�P$+IH.+.*BU ;7E9$-�S$HIROPa&�&)J6:�H.S�:6*,&)R+./w: 7bU'7b*,&)M ()-0/c*,&>=T*�|ª+�3�&�35Xfk�¥ i�%w()-0MGFa-0/�&8/c*,7u&8M@PQ&8R�R$&8Rz+I/z: 9$-�7�*s7�UT7�*E&8MZ~>3 k�¥ i�%7�S$F$F$H.+I&)CE7d7E9�-0S$HIRG:�H.7E-�()-0/$7E+.R$&8CdMN:�D]+I/�?f:KJ6:�+.H�:�P�HI&�MN-0C�&�R$&)*,:�+IH.&8R�+./�^{-0CEMN:6*E+I-0/�CE&)?c:�CER�+I/$?�*,9�&PQ&89$:KJT+.-0C�-�^�*,9$&)+IC�7bU'7b*,&)MN7)X�:�/�Rj()&8Cb*,+.^tUT+./$?2*,9�:;*�*E9$&8+.C (8-�MNFQ-0/$&)/]*E7f7,:6*E+I7�^tU�:v7EFQ&8(8+���&8Rj7E&>*-6^�Pa&)9�:�J'+.-0C,:6HYF$C�-0FQ&8C�*E+I&)783�nB/p:�R$R�+.*,+.-0/�XQ:Z^{-0C�MZ:�HWC�+I7EDs:�7�7E&87�7EMG&8/c*f-�^�CE&)x]S$+IC�&8MG&8/c*,7 7�9$-0S$H.RPQ&�FQ&8C�^{-�CEMG&8Rv*g:�D]+./$?q+I/c*,-G:�()(8-0S$/c*�*,9�&�(g9$:�C,:�(>*,&)CE+I7b*,+.(87�-�^Y9$-07�*�7bU'7b*,&)M &)/cJ'+.CE-0/�MN&)/]*E783 �

� 7�7�&8&8/G^{CE-0M *,9$&�&>='()&8CEF'*,78X'MN-�7�*�-�^Q*,9$&)7E&�(8-0/'^{&8CE&)/$(8&\F�:�FQ&8C�7�C�& ��&)()*�^ª:�+IC�H.UO7ED6&8F�*E+I(�:6H¡JT+.&)A�7�-�^R$&>J0&8H.-0F$+./$?u:�/$R�(8-�/���?0S$C�+I/$?�MG+I7�7E+I-�/'�B()CE+.*E+I(8:�H�7�UT7�*E&8MG7f-0S�*f-�^�(8-�/]J�&8/c*,+.-0/�:�HdMN:�+./$7�*ECE&�:6M k�¥ i�%F$C�-'R$S�()*,7)X$A�+.*E9sMN:�/cU2(8:KJ�&�:6*E783

�����T� � ����� � �����$� �"� � �d���d�f� � ! �

y�&8HI+I:�P$+.HI+.*BU�X8^ª:�S$H5*W*,-0H.&8C,:6/$(8&6X67�&8(8S�CE+.*BU�Xc:�/$RO+I/$R�&8&8R_7ES$CbJ'+5J6:�P$+IH.+.*BULM@S$7�*YPQ&"()-0/$(8&)F�*,S$:�HIH5Uf+I/c*,&)?0C,:�H0*E-9�:�C�R�A�:�CE&":�/$R�7E-�^t*BA�:�C�&�X�R�&87EF�+.*,&�*,9�&�R�&87E+.CE&�*,-�S$7E&�-�`¡��*E9$&>��7E9$&)H.^TA�&8:�DcA<:�C�&<:�7�*E9$&"P$:�7E+.7W^{-�C�(8CE+5*,+.(�:�H:�F$F�HI+I(8:6*,+.-0/$7)3�nB/�F�CE+I/�(8+IF�HI&�X¡MN:�+I/�7�*,C�&�:�M ()-0/$(8&)F�*,7�7�9$-0S$H.R�PQ&_S$7�&8R�A�9$&8C�&�:�F$F�HI+I(8:�P$H.&�XQ:�H.*E9$-0S$?�9*,9�&8+ICf7�9$-0C�*E(8-0MG+I/�?07�M@S$7b*OPQ&G-¤J�&8C�(8-0MG&�3 �f-T-'Rp7�-�^t*BA<:6CE&G&8/$?0+./$&8&)CE+./$?�F$C,:�(>*,+.(8&q7E9$-�S$HIRjPa&GS$7�&8R+I/�:�F$F$H.+I(8:6*,+.-0/$7�:�7�A�&)HIHY:�7L7bU'7b*,&)M R$&>J0&8H.-0F$MG&8/c*�3�i�9$&@&)/c*,+IC�&_F$C�-'()&87�7 -�^dF$C�-0?0CE:�M�R$&)J�&8H.-0F$MG&8/c*

� �

Page 108: Practical Architectures for Survivable Systems and Networks (Phase

7E9�-0S$HIRqPQ&<7�UT7b*,&8MN:6*E+I[8&)RGA�9�&8CE&>J0&)C"FQ-07E7�+IP$H.&�3Ye�-0CEMN:�HTMN&>*,9$-TR$7d7E9�-0S$HIR�PQ&�:�F$F�HI+I&)R@*,-�F�:6C�*,+.(8S$HI:�CEH5U(8C�+.*E+I(�:6H�:�H.?0-0CE+5*,9$MG7<:6/$RsF�CE-0?0CE:�MG783� F�:�Cb*,+.(8S$HI:�CEH5Uj*E9$-0C�/]U :6CE&�:�+./]J�-0H.J�&87�*,9�&u/�&8&8R ^{-0C�MG&)*,C�+I()7@Fa&)CEMG+.*�*,+I/�?�*,9$&�R$& ��/$+5*,+I-�/§:6/$R

:�/�:6H.UT7E+.7d-�^�7�S$C�JT+.J6:�P�+IHI+5*BU_C�&8H.&)J6:�/c*":6*E*ECE+IP�S�*,&)783�¥ /G-0/$&�9�:�/$R�X]C�&8HI+I:�P$+.HI+.*BU�C�&8x]S$+IC�&8MG&8/c*,7�:�/�RN^ª:�S$H5*��*,-�HI&8CE:�/$()&�MG&8(g9$:�/$+I7�MN7Y:�C�&"/$+.(8&)H.Uf:�MG&8/$:�P$HI&d*E-\MG&)*ECE+I()7#:�/$R_F�CE-0P�:6P$+IH.+I7�*E+I(d:6/�:�H.UT7�+I783�¥ /O*E9$&"-6*,9$&)C9�:�/�R�XL7�&8(8S�CE+.*BUr:�/$R 7ES$CbJT+.J6:�P$+.HI+.*BU *E&8/$R *,-�PQ&�M@S$(g9wHI&)7E7v&�:67E+IH5U�(g9$:�C,:�(>*,&)CE+I[)&8RwS$7E+./$? MN&>*,C�+I(87� A�+.*E9 ��S�7�*s: ^{&>A &>='()&8F�*E+I-0/$7)3�¥ /$&p7ES�(g9�&>='()&8F�*E+I-0/z+I/cJ0-0H5J0&)7uA"-0CED�^ª:6()*,-�CE7�CE&)?c:�CER�+I/$?�*,9�&&)`a-0Cb*�*,-�P$C�&�:�DZ:q?�+.J0&)/�(8C�UTF�*E-0?0CE:�F$9$+.(f:�HI?0-�CE+.*E9$Mu3�V�-¤A"&)J�&8C)X¡*E9$&�7E+.MNF�HI+I7b*,+.(L:�F�F$HI+.(�:6*E+I-0/N-�^#7ES$(g9MG&)*,C�+I()7Z+I7ZR�:�/$?0&)CE-0S�783 e¡-�CZ&>=�:�MGF$H.&�X�*,9$&�+IMGF$HI&)MN&)/]*,:6*,+.-0/ -�^O:?0+.J�&8/r7�*ECE-0/�?�(8C�UTF�*E-0?0CE:�F$9$+.(:�H.?0-0CE+5*,9$MoMN:�U@PQ&�*ECE+5J'+I:�HIH5Uf(8-0MGF$C�-0MN+.7,:�P�HI&"^{C�-0M PQ&8H.-KAfX0^{CE-0M¦A�+.*,9�+I/�X0-�C ^{CE-0M -0S�*,7�+IR$&6X]Pa&)(�:�S$7�&-�^�JTS$H./$&8CE:�P$+IH.+.*E+I&87�+./h*,9�&Z-0FQ&8CE:6*,+./$?�7bU'7b*,&)M -0C�*,9$&v:6F$F$HI+.(�:6*E+I-0/p+./hA�9$+I(g9 *,9$&2()C�UTF�*E-0?0C,:6F$9cUh+.7&8M_Pa&)R$R$&8R«3 � /$-�*E9$&8Cd&�=�:�MNF�HI&<+.7d:�/G:6*E*E&8MGF�* *E-�(8-0MG&�S$F�A�+.*E9@*,9$&�7�&8(8S�CE+.*BU@-�^a: ?0+.J�&8/q-0FQ&8C,:;*,+I/�?7�UT7b*,&8Mu3 nB/z?0&)/$&8CE:�H�X\?0+.J�&8/z:�HIH\*,9$&pD]/$-KA�/ �¡:�A�7)X *,9$&�A"-0S$HIRT�BPQ&j7�&8()S$CE+5*BU +I72*BUTF$+I(8:�HIH5U�&8:�7E+.H.UFQ&8/$&>*,C,:;*,&8R �_^{S$C�*E9$&8C�MN-�CE&�X\*,9$&jHI+.D�&8H.+I9$-T-TRr-�^_S�/$D]/$-KA�/ �¡:�A�7s7�9$-0S$H.RzMN:�D�& :�/cU x]S�:�/c*,+5*g:6*E+.J�&MG&�:�7�S$CE&)7�-6^�7�&8(8S�CE+.*BU�7�S$7EFQ&8(>*�3" \&>J0&8Cb*,9$&)HI&)7E78X¡*,9�&O:6F$F$CE-�F$CE+I:6*,&�S$7�&O-6^�MG&)*ECE+I()7�+I7�R$&)7E+.C,:�P$H.&�3� 7GR$&)7E(8C�+IPQ&8R�+./�%T&8()*E+I-0/ 1$3 ��X�*E9$&s7�S$FQ&8CE()-0MGF$S�*,+./$? ��&8H.R�9�:�7G7ES'`«&)CE&8R�+I/ *,9$&sF�:�7�*G^{CE-�M :

7E&)CE+.-0S$7�(�:67E&�-�^�M_U0-�F$+�:�3%'-0MG&2-�^�*,9�&uH.&87�7E-0/$7@*E9�:6*q(8:�/ Pa&vR$CE:�A�/ ^{C�-0M *E9�:6*q&�=�FQ&8C�+I&)/$(8&u:�C�&R$+.CE&8(>*,H5Uv:�F$F�HI+I(8:�P$H.&L*,-�*,9�&�/�&8&8R�^{-0C�9$+.?09$H.UN7ES�C�JT+.J6:�P$H.&�7�UT7�*E&8MG7L:6/$Rs/�&)*BA"-0CED]783%'&>J0&8CE:�H]Fa-6*,&8/c*E+�:�H.H.U�S$7E&>^{S$H]CE&)7E&�:6CE(g9_R�+ICE&)()*E+I-0/$7W:6CE&�:�HI7�-�/$-�*,&)ROPQ&8H.-KAfX;+./O%'&8(>*,+I-�/$7 �'3.4K��:6/$R_¢'3��'3

������� � � � ��� � "�b�W����� ���

i�9$+.7dCE&8FQ-0Cb*�R$-'&)7d/$-�*�:6*�*,&)MNF�*�*,-�CE&)F$HI+.(�:6*E&�*,9�&�J6:�7b*�HI+5*,&8CE:6*,S�CE&�-6^Q*E&8(g9$/�+Ix]S$&87�^{-0C ^ª:�S�H.*�*E-0HI&)C,:�/�(8&�3e�-0C<&�=$:6MNF$H.&�X�*E&8(g9$/�+Ix]S$&87�^{-0C<+./$(8C�&�:�7�+I/$?�7bUT7�*,&)M�CE&)HI+�:6P$+IH.+.*BUq+I/vC�&87�Fa-0/�7E&�*,-q9�:�C�R�A�:�CE&�^ª:�S$H5*,7�:6/$R(8-�MNM@S�/$+I(8:6*,+.-0/$7�^ª:�+IH.S$CE&)7Z:6CE&�&�=�F�HI-0C�&8R�+./�?0&8/�&8C,:6HL+I/ ��1 ��X�¢���X\4K� �'X\4K��4�X\4K�0¢TX<�610��X<�6¢ �'X ��404�X��4�1'X � ��� }3ve¡:�+IH.S$CE&�C�&8()-¤J�&8CbUh+./j*E9$&N()-0/c*,&�='*_-�^�iY:�/$R$&)M ��7O \-0/¡%]*,-0Fk�HIS$7b*,&8C�7_+.7�()-0/$7�+IR$&)CE&8RhP]U� :�P�:6CE7EDcU � �0¢ ��}XdCE&8F�CE&87�&8/c*,+./$?j:�7E&)CE+I-�S$7@7�*E&8F�*,-KA�:�CER�7bUT7�*,&)MN+.(Z^ª:�S$H5*_*E-0HI&)C,:�/$()&�3j%'-�MN&27�+I?0/�+����(�:6/]*qC�&8()&8/c*qCE&)7E&�:6CE(g9 -�^\�fS�HID;:�CE/�+�:�/�R � CE-0CE:�CE&)H�:6*E&87_*E-�(8-0MGFa-�7E+.*E+I-0/$:�HI+5*BU�F$C�-0Fa&)C�*E+I&87_-�^�^ª:�S$H.**,-�HI&8CE:�/$()& ���0�TX�4 ��¢ �:�/$R�*,9$&f7E-�MN&>A�9�:6*�(�:6/$-0/$+.(�:�H�R�&8(8-�MNFQ-07E+5*,+.-0/v-�^#^ª:�S$H.*b��*E-0HI&)C,:�/c*<R�&87E+.?0/$7�+I/c*E-� �� ���� �����<:�/$R ����� ������ ����� ��� � }3¥ /$(8&N:�?c:6+I/jR$&8MG-0/$7b*,C,:;*,+I/�?u*E9$&NR�&87E+.C,:�P�+IHI+5*BU�-�^�:s(8-�/ ��S$&)/$(8&2-6^<CE&)x]S$+IC�&8MG&8/c*,7_:�/$R:u(8-0C�CE&��

7EFQ-0/$R�+I/$?�(8-0/ ��S$&8/�(8& -�^a*,&)(g9$/$+Ix]S$&)7�^{-0C�(8-�M@P�:6*�*,+I/�?�7�&8()S$CE+5*BUZ:6/$RZC�&8HI+I:�P$+.HI+.*BU�F$C�-0P$H.&8MG7":6HI-0/$?f*,9�&HI+./$&87O-�^�*,9$&vC�&8()-0/cJ0&8C�?0&8/�(8&u-�^\:KJ6:�+.H�:�P�+IHI+5*BU�C�&8x]S$+IC�&8MG&8/c*,7�+./ e�+I?�S$CE&��3.4�Xd(8-0/$7�+IR$&)C_*,9�&vCE&8x]S$+.CE&��MG&8/c*,7d^{-0CdR�:;*g:�+I/c*,&)?0CE+5*BU@+./q*E9$&�7E&)/$7E&�-�^�/�-6�BS$/�+I/c*,&)/$R$&8RT�B(g9�:�/�?0&�7E9$-KA�/2:;*d*,9$&�/$-TR$&87�R$&)7E+I?�/�:6*,&)RPcU :p7E9�:�C�F¨|��q~_+I/�*,9$& ��?�S$CE&63 � :;*g:�+I/c*E&8?0C�+.*BU(8:�/ Pa&v&)/$9�:�/$()&8R *,9$C�-0S$?09 (8CbU'F'*,-0?0CE:�F$9$+.(v+I/'�*,&)?0CE+5*BU�(g9$&8(gD]7G|t*BU'F�+I(�:6HIH.UN*,-NF$CE-�*E&8(>*�:�?c:6+I/$7b*\MN:�H.+I(8+.-0S$7�:6H.*,&)C,:6*E+I-0/�7g~�-0C�&8C�CE-0C��B(8-�CECE&)()*E+I/$?G(8-TR$+I/�?*,&)(g9$/$+.xTS�&87�|t*BUTF$+I(8:�HIH5Uh*,-jF$C�-�*,&)()*Z:�?c:�+./$7�*G:�()(8+.R$&8/c*g:6H�?0:�CEP$H.+I/$?c~>3 V\-KA"&)J0&)C8X�:�/ +I/c*E&8CE&)7�*E+I/$?jCE&��(8&)/c*�7EFQ&8()+�:�H �BF$S$C�Fa-�7E&GS$7E&N-�^�(8-TR$+./$?s^{-0C�R$&>*,&8(>*,+./$?�MN:�HI+.(8+I-�S$7L*g:6MNFQ&8C�+I/$?s:�7OA"&8H.H�:67@:�()(8+IR�&8/c*g:�H&8C�CE-0C�7f+I/p-0/$()&>��A�C�+.*,:�P$HI&_-0F�*,+.(�:�H�R$+I7�DT7f+.7�?0+.J�&8/jP]U �H�:�S�M &)*O:�H}3 � 101 }X�*g:�D]+I/�?s:6R�J6:�/c*g:�?0&�-6^�*,9�&:�7bU'MGMG&)*,CbUZ+./$9$&)CE&8/c*�+./2(8&)C�*g:6+I/v-0/$()&>��A�CE+.*,:�P$H.&L7�*E-0C,:6?0& MG&8R$+I:_+I/2A�9$+.(g92A�CE+5*,+I/�?@(�:�/v(g9$:�/$?0&�*,9�&7�*,:6*,&�-�^L:pP$+.*�-�/$H.Uh+I/ -0/$&�R$+.CE&8(>*,+.-0/z|ª&�3�?$35X�^{C�-0M :p/$-�*qF�CE&)JT+.-0S$7EH5UA�CE+5*E*E&8/ �� ���2P$+5*�J6:�HIS$&2*E-:�A�CE+5*E*,&)/ � � _P$+5*�X�P$S�*G/$&>J0&8Cq*,9�&sC�&)J0&)CE7�&K~>3 i�9$+.7G+.7q:�/$-�*E9$&8Cq&�=$:6MNF$H.&v-�^L:j()CE-07�7E-KJ0&)CN+.MNF$H.&>�MG&8/c*g:6*E+I-0/G*,9�:;*�(�:�/Z7E+IM_S$H.*,:�/$&8-�S$7EH5UZ:6R$R$CE&)7E7�R$+5`«&)CE&)/]*�7E&>*,7�-�^W7�S$P$CE&)x]S$+IC�&8MG&8/c*,7�7b*,&8MGMG+I/$?�^{CE-0M

���

Page 109: Practical Architectures for Survivable Systems and Networks (Phase

-�*E9$&8CbA�+I7E&�+I/�R$&8FQ&8/$R�&8/c*���7E&8&)MN+./$?GMZ: ��-�C�CE&8x]S$+.CE&)MN&)/]*E783"nB/s7�S$(g9�(8:�7E&)78XQ(8-0/$7�+IR$&)C,:�P�HI&fPa&)/$& ��*L(8:�/PQ&L-0P�*,:�+I/�&8R2PcUNCE&8()-0?0/$+.[8+./$?O*E9$&L()-0MNMG-0/�:6HI+.*BU�:�MN-�/$?O-6*,9$&)C�A�+I7�& +I/�R$&8FQ&8/$R�&8/c*�7ES�P$CE&)xTS�+ICE&)MN&)/c*,7:�/$R�*,9�&8/uF$CE-KJT+IR$+./$?q:qS$/$+��$&8Rv*,C�&�:6*EMN&)/]*�+./�*E9$&fR$&87�+I?0/u:�/�Rs+.MNF$H.&8MG&8/c*g:;*,+I-�/�3

������� � ��������� ��� �T���#! �w� ��� � �$���

©�:�/cUs*,&8(g9�/$+Ix]S$&)7�&�='+I7�*L^{-0C\*E9$& ������ ���� #:�/�:�H5UT7E+I7\-�^�7�UT7�*E&8M PQ&89$:KJT+.-0C8XaP�:�7E&)Rp-0/�(8-0/�7E+IR�&8C,:;*,+I-�/-�^"CE&)xTS�+ICE&)MN&)/c*,78XYR$&87�+I?0/p7�Fa&)(8+��$(�:6*E+I-0/$7)XY+.MNF�HI&8MG&8/c*,:6*,+.-0/�X�:6/$R -�Fa&)C,:6*E+I-0/�:6H�F$C�-'()&8R$S$C�&87)3Zi�9$&)7E&*,&)(g9$/$+.xTS�&87�MZ:�UvPQ&�^{-0CEMN:�Hd|{7E&)&_%T&8()*E+I-0/ �'3�¢c~�-0C�+./�^{-0CEMN:�H}3 � =�:�MNF�HI&87�-6^�7�S$(g9s*E&8(g9$/$+.x]S$&87L:�CE&

2 � /�:�H5U'7�+I7�-�^#*,9�&�+./c*,&8C�/�:�H�()-0/$7�+I7�*E&8/$(>Us:�/$R�(8-0MGF$H.&)*,&)/$&87�7\-6^�C�&8x]S$+IC�&8MG&8/c*,72 � /�:�H5U'7�+I7�-�^#*,9�&�()-0/$7�+I7�*E&8/$(>U�Pa&>*BA�&)&8/�R�&87E+.?0/u:�/$RuCE&)xTS�+ICE&)MN&)/c*,72 � /�:�H5U'7�+I7�-�^#*,9�&�()-0/$7�+I7�*E&8/$(>U�Pa&>*BA�&)&8/�R�&87E+.?0/u:�/$Ru+IMGF$HI&)MN&)/c*g:6*E+I-0/2 � /�:�H5U'7�+I7@-6^\-�Fa&)C,:6*E+I-0/�:6H"F$C�-'()&8R$S�CE&87s|{&�3�?$3.X�()-0/���?0S�C,:6*E+I-0/�()-0/c*,CE-�Ht~_:�/�R*,9$&)+IC@()-0/$7E+.7�*E&8/$(>UA�+5*,9�CE&)x]S$+IC�&8MG&8/c*,72 "H�:�(gD0�BPQ-�=w:�/�:6H.UT7E+.7h|tA�+.*E9z/$-§D]/$-KA�HI&8R�?0&h-�^O*,9$&j+I/�/�:�CER�7g~v:�/$Rz-0Fa&)/'�BPQ-�= *,&)7�*,+./$?�|{A�+.*E9()-0MGF$HI&>*,& D]/$-KA�HI&)R$?0&�-�^#*,9$&f+I/�/�:�CER�7g~>X'A�9$&)*E9$&8C�A�+.*E9u*E&87�*E+I/$?q-0C<^{-�CEMN:�H«MG&)*E9$-'R�7

2 k�-�MNF$+.HI&)C\()-0/$7E+.7�*E&8/$(>U�(g9$&8(gD]+./$?�:6/$Rp+IMGF$H�:�/c*,:6*,+.-0/s-6^"R'U'/$:�MN+.(@(g9$&)(gDT7O:�7f:2PcUTF$CE-TR$S$(>*f-�^()-0MGF$+IHI:6*,+.-0/2 y�+I7�D2:�/$:�H.UT7E+.78X$C�+I7�DZMN:�/�:�?0&)MN&)/c*�X�:�/�RsC�+I7EDNMN+5*,+.?c:6*,+.-0/2 nB/�R$&8FQ&8/$R�&8/c*\J�&8C�+���(8:6*,+.-0/u:�/$R�J�:6HI+IR$:6*,+.-0/2 ldC�-'R$S�()*�(8&)C�*,+���(�:;*,+I-�/nB/�:�R�R$+.*E+I-0/�X;&)J6:�H.S�:6*E+I-0/�-�^$*E9$&<F$C�-'()&87E7�&87 *E9�:6* S�/$R$&8C�HI+.&"7bU'7b*,&)M R$&>J0&8H.-0F$MG&8/c*dMN:�UfFa-07�7E+.P$H.U�PQ&

-�^�+./c*,&8C�&87b*�3 � H.*E9$-0S$?09O7ES$(g9_F$CE-T(8&)7E7 ()&8C�*E+���(8:6*,+.-0/�R$-'&)7�/$-6*�/$&)(8&)7E7,:6CE+IH5U�7,:�U�M@S$(g9�:�PQ-0S�*�:\7�Fa&)(8+���(R$&>J0&8H.-0F$MG&8/c*�X'+.*�MN:KUqPQ&�S$7E&>^{S$H«+./GA"&8&)R$+I/$?_-0S�*�*,9$&\-0S�*,H.+I&)CE7dA�9$-@:6CE&�(8-0MGF$HI&>*,&)H.UqS$/$x]S�:6HI+��$&8R��+.^W*E9$&f&)J6:�HIS$:6*,+.-0/v+I7�+5*,7E&)H.^YMN&8:�/$+./$?�^{S$H}�

2 k�&)C�*E+���(8:6*,+.-0/�:�/$RuHI+.(8&8/�7E+I/�?�-�^�R�&)J0&)HI-0F�MN&)/]*�FQ&8C�7E-0/$/�&8H"|{^{-0C�&�=�:�MNF�HI&�X�7E&8& ��� � ���~2 k�&)C�*E+���(8:6*,+.-0/h-�^<R$&)J�&8HI-�Fa&)C@(8-0MGF�:�/�+I&87_:�/$R-6^�*,9$&)+IC�R$&)J�&8HI-�F$MN&)/c*�F$CE-T(8&)7E7�&878X�7ES�(g9 :�7_*,9�&k<:6CE/$&)?0+I&��b©s&)HIHI-�/�%'-�^t*BA�:�CE& � /$?0+./$&8&)CE+I/�?GnB/�7�*,+5*,S�*E& ��7\k<:�F�:�P$+.HI+5*BUv©�:;*,S$C�+.*BU�©u-'R$&)H|{9c*E*,F«��m0m¤A�A�Af3�7�&8+�3�(8M_S�3�&)R$S¡m�:6()*,+5JT+.*,+.&87,m6(8MGM2m�~

������� � �_�W�����$�b"� ��� � ���d�«�������

� H5*,9$-�S$?09�*,9�&�F$CE+.MZ:�CbU�&)MNF�9�:�7E+.7�-�^�*,9$+.7 CE&)Fa-�C�*f+I7L-0/p7�UT7�*E&8M :�/$Rp/$&>*BA�-�CED�:�C�(g9$+.*E&8(>*,S$C�&878X#-0F'�&8CE:6*,+.-0/�:�HQF$CE:�()*E+I(8&�+.7�:�P$7�-0HIS'*,&8H5UG(8CE+5*,+.(�:�H¡*,-q7ES�C�JT+.J6:�P$+.HI+5*BU03�i#-TR�:�U ��7�7�UT7b*,&8MG7�:�/$R�/$&>*BA�-0C�D]7�F�H�:�()&&8/�-0CEMG-0S$7OP$S$CER�&8/$7�-0/h7�UT7�*E&8M :�R�MN+./$+I7b*,C,:;*,-0C�7O:6/$R7E&)(8S$C�+.*BUhFa&)CE7E-�/$/$&8H}3�nBR$&8:�HIH5U0X�7bUT7�*,&)MN7q:6/$R/$&>*BA�-0C�D]7 7E9$-�S$HIR�PQ&�R$&87�+I?0/$&)R�:�/$R�+IMGF$HI&)MN&)/]*E&8R�*,-N+I/$()CE&�:67E&O*E9$&�MZ:�/$:�?0&�:6P$+IH.+.*BU2-6^d-0FQ&8C,:;*,+I-�/$78X

�%w

Page 110: Practical Architectures for Survivable Systems and Networks (Phase

:�/$R *,9$&NCE&8x]S$+.CE&)MN&)/]*E7O^{-0CO-0FQ&8C,:;*,+I-�/$7O7�9$-0S$H.RhPQ&Z+./$(8H.S$R$&8R S$Fh^{C�-0/c*�Xd:�7O/$-�*E&8R+./�%'&)()*,+.-0/ �'3�1$3nB/$R$&)&8R�X�:6/]U (8H.&�:�/�HI+I/�&87E7_:�/$R()-0/c*,C�-0HIHI:�P$+IH.+.*BUs+I/$9�&8CE&)/c*�+I/h:�CE(g9$+5*,&)()*,S�CE&87_(�:�/F�H�:�U :�MZ: ��-0COC�-0HI&+I/�+.MNF$C�-KJ'+./$?@*,9�&�-�Fa&)C,:6*E+I-0/�:6H�F$C,:6()*,+.(8&63�i�9�&_:�F�F$CE-c:6(g9$&87�R$+I7�(8S$7�7E&)R�&�:6CEHI+.&8C�+./�*E9$+I7�(g9$:�F�*,&)CL:6/$R*,9�&u7b*,C�S$()*ES$C,:�H�()-0/$()&8F�*E7N&�=$:6MN+./$&8R +I/§k�9�:6F�*,&)CZ��(8:�/§9�&8HIF«3 � H.7E-p+IMGFa-�C�*g:6/]*�:�CE&vMG-0/$+5*,-0C�+I/$?^ª:�()+IHI+5*,+.&87Y*E9�:6*":�C�&\:6(8(8S�C,:6*E&�X]*,+IMG&8H5U0Xc:6/$RGJT+.7ES�:�H.H.U_S$/$R$&)CE7�*,:�/$R�:6P$HI&63di�9TS�78XT+I/$()HIS$R$+./$?�-0FQ&8CE:6*,+.-0/�:�HCE&)x]S$+IC�&8MG&8/c*,7�:�MG-0/$?�*,9�&�R�&87E+.CE&)Rs7bU'7b*,&)M�(g9�:�C,:6()*,&)CE+.7�*,+.(87�+I7�+.MNFQ-0Cb*g:�/c*<^{C�-0M *E9$&f-0S�*,7�&)*83� /q+.MNFQ-0C�*,:�/c*d:�F�F$CE-c:6(g9G*E-�(8-0/c*,C�-0HIH.+I/$?L7�UT7�*E&8M :�/$Rq/$&>*BA�-�CED�PQ&89�:�JT+I-0Cd+./cJ0-0H5J0&87�C�&�:�H ��*,+.MN&�R$&��

*,&)()*E+I-0/�:6/$Rq:�/�:�H5UT7E+I7#-�^¡FQ-�*,&)/c*,+�:6HIH.UfS�/$R$&87�+ICE:�P$HI&"R$&)JT+I:6*,+.-0/$7Y^{C�-0Mo&>='FQ&8()*E&8RqPQ&89�:�JT+I-0C)X0(8-�/$7E+.R$&8C�&8R+I/s%'&)()*E+I-0/ �'354 �'3

����� � �r�W���.¤���b! � �z� ��� � �$���� � � � � ���\�b�� ��� ���r�W� �_"� ���

� 7L/$-�*,&)R�+I/p%T&8()*E+I-0/�1�3.40XQ*,9$&)CE&�+.7 :Z?0C�&�:6* /$&8&)R�^{-0CL*,9�&�:�P$+.HI+.*BUZ*,-vF$C�-¤JT+.R$&@CE&8:�H5��*,+.MN&fR$&>*,&8(>*,+.-0/:�/$Rs:�/�:6H.UT7E+.7�-�^�7bUT7�*,&)M :�/$Ru/$&)*BA"-0CEDvPQ&89$:KJT+.-0C8X$A�+5*,9u:�F$F$C�-0F$C�+�:6*E&�CE&�:6H5��*E+IMG&LC�&87EFQ-0/$7�&87 � ^{CE-0M*,9�&\()-'-0C�R$+I/$:6*,&)RGFQ&8C�7EFQ&8(>*,+.J�&\-6^�7ES�C�JT+.J6:�P$+.HI+5*BU@:�/�RZ+.*E7d7ES$P'*,&8/�R$&8R2C�&8x]S$+.CE&8MG&8/c*E783di�9$&)CE&L9$:�7�Pa&)&8/(8-�/$7E+.R$&8CE:�P$HI& A"-0C�Dv-0/v*,9$+.7<*,-0F$+.( ^{-0C�MG-0CE& *E9�:�/s:qR�&8(�:6R$&�3%�y�n�9�:�7NF$+I-0/�&8&8C�&8R�A"-0CED -0/�C�S$HI&��BP�:67E&8R�&>='Fa&)C�*v7bUT7�*,&)M :�/$:�H.UT7E+.7Z:6/$Rr7�*,:6*,+.7�*,+.(�:�H�:�/$:�H.UT7E+.78X

*,9�CE-0S$?�9¨n � � % |ªnB/c*,C�S$7E+.-0/ � &)*E&8(>*,+I-�/ � =�FQ&8Cb*j%TUT7�*E&8M � 4K£�¢��~�:�/$R� �n � � % |} �&>=T*�� �f&)/$&8CE:6*,+.-0/n � � % � 404�X�4¤�TX�4�1]�'X�4 ��¢��~>3�i�9$&s(8S$C�CE&)/]*GA"-0CED -0/ � © � y � ¬ � | � J0&)/]*�©s-0/$+5*,-0C�+I/$? � /�:�P�HI+I/�?y�&87EFQ-0/$7�&87�*,- � /$-0MN:�HI-�S$7�¬�+.J0& � +I7b*,S$C�P�:�/$()&87,~ � 4K£c�]X ����1�X �0� � Q+I7d*,9$&�(8S�CECE&)/c*<&>=T*E&8/$7�+I-0/2-6^�n � � %:�/$Rs \n � � %v*,-GMN-0/�+.*,-�C</$&)*BA"-0C�Ds:6()*,+5JT+.*BU03<¥LJ0&8CE:�HIH}X�A"&OD]/$-KAo-�^�/$-N&>`«-�C�*,7�-�*E9$&8C�*,9$:�/ � © � y<�� ¬ � *,9$:6*v:�C�&�-0CE+.&8/c*,&)R�*,-KA�:�CER�*E9$&p:�P$+.HI+.*BU�*E-�R$&)*E&8(>*�F$CE-0P�HI&8MG72:6CE+I7�+I/$?h+I/�()-0/$/$&)()*,+.-0/�A�+.*E9?0&)/$&8CE:�HI+.[8&8R�7�S$C�JT+.J6:�P�+IHI+5*BU03�|}%'&8&f9c*E*EF���m0m;A�A�Af3�(87EH}3�7�CE+}3�()-0M2m;+I/c*,C�S$7E+.-0/�3�9]*EMNH}3�~¥L^�(8-0S$C�7E&6X�MZ:�/cU�-�*,9$&)C +I/�7�*,+5*,S�*E+I-0/�7L9�:�J0&qPQ&8&)/jR�&)J0&)HI-0F�+I/$?�7�UT7b*,&8MG7�:�R$R$C�&87�7E+I/�?2J�:6CE+I-�S$7�:�7��

FQ&8()*E7�-�^�*,9�& +I/c*,C�S$7E+.-0/'��R$&)*E&8()*E+I-0/NF$CE-�P$HI&)MsX]*BUTF$+I(8:�HIH5UqS$7E+./$?�&8+5*,9$&)C�CES�HI&>��P�:�7�&8R2*,&)(g9$/$+.xTS�&87�-0C"7�*g:¤�*,+.7�*E+I(�:6H�:�/�:�H5U'7�&87)X P$S�*_+I/jMN-07b*_(8:�7E&)7@/$-�*OPQ-�*,9�X�:�/$R S$7ES�:6HIH.UpR�&�:�H.+I/$?�A�+.*E9hS$7�&8CE7_-�^�+I/�R$+.JT+IR�S�:�H7�UT7b*,&8MG7�-0C�HI-T(�:�H�/�&)*BA"-0CED]783�%'&8& � R�A<:6CER � MN-�CE-07�- ��7�/$&>A�PQ-'-0D � 4�� �^{-0C�:�/u+I/c*,C�-'R�S$()*E+I-0/v*,-q*,9�&��&)HIR�3 ©�:�/cU_F$:�Fa&)CE7d:6CE&"A"-0Cb*,9�CE&8:�R$+./$?$X�+./$(8H.S$R$+./$?���� ��X6£�40XT4¤� �TX'4 �6�'XT4 �0�'X �0� �TX ��1c� �3 �C,:6R$HI&>U ���c��(8-�/$7E+.R$&8C�7 *,9$&<&>`«&)()*E7d-�^QR$+I7�CES$F�*E+.J�&<CE-0S'*,&8C�783 nB/q:6R$R$+.*E+I-0/«X6-0/�H.U_:\^{&)A§&)`a-0C�*E7 9�:�J0&�:6R$R$CE&)7E7�&8Rq^ª:�S$H.*R$&>*,&8(>*,+.-0/s+./v*,9$+.7�(8-0/c*,&�=T* � ^{-0C�&�=�:�MNF�HI& � 4�1c�'X�4�¢ �'XQ����£�}3%'(g9$/�&8+I&)C�:�/$R��f&)HI7�&)U � ��10¢ �9$:KJ�&�R$&)J�&8H.-0Fa&)Rp:Z(8CbUTF�*,-0?�C,:�F$9�+I(�:6HIH.U�P$:�7E&)Rj7b*,&)F�*,-KA<:6CER�*,9�&@7E&��

(8S�CE+I/�?G-6^ :�S�R$+.*�H.-0?07�:�?c:6+I/$7b*<*g:�MGFQ&8CE+./$?q:�/$RuPcUTF�:�7E7�+I/$?�3� /�-�*,9$&)Cu^{-�CEM -�^_CE&8:�H5��*,+IMG&�:�/$:�H.UT7E+.7v+I/cJ0-�H.J0&)7�R�UT/�:6MN+.(j/�&)*BA"-0CED MN:�/�:�?0&)MN&)/c*�3  \&)*BA"-0C�D

MN:�/�:�?0&)MN&)/c*q7E9$-0S�HIR§:�HI7�-jPQ&�+I/c*,&)?0C,:;*,&8R A�+.*E9§C�&�:�H ��*E+IMG&2:�/$-�MZ:�H5U�:�/�R§MG+I7�S$7E&�R$&>*,&8(>*,+.-0/�:6/$RCE&8:�H5��*,+.MN&\CE&8()-0/���?�S$C,:6*E+I-0/u:�7�:�CE&)7ES$H5*�-�^ R�&)*,&)()*E&8R�F�CE-0P$H.&8MG783

������� � ����� ���d�����

%T*,:�/$R�:�C�R$7f:�C�&�+IMGFa-0Cb*g:�/c*8X�P$S�*f(8:�/j:�HI7�-vPa&�&�='*ECE&)MN&)H.U�()-0S$/c*,&)CEF$C�-'R�S$()*E+.J0&q+5^"FQ-T-0CEH5U�()-0/$(8&)+.J�&8R-0C"MN+.7,:�F$F�HI+I&)R�3dk�9$:�F�*,&)C��_(8-�/$7E+.R$&8C�7<*,9$& &�='+I7�*E+I/$?@:�/$Rv&8MG&8C�?0+I/�?_&)J6:�H.S�:6*E+I-0/N(8CE+5*,&)CE+�:'3 � F�Fa&)/$R$+5=k¦7�S$MGMZ:�C�+I[)&87�7E-�MN&q-�^�*,9$& � &)F�:�C�*EMN&)/c*O-6^ � &>^{&8/$7�&N&>`«-0Cb*,7�*,-�7b*g:�/$R$:�CER$+.[8&G:�C�(g9$+.*E&8()*ES$CE&)7_:6/$R7E&)(8S$C�+.*BUq7�&8C�JT+.(8&87)3�nB/NF�:6C�*,+.(8S$HI:�C8Xc%'&8(>*,+I-�/2kL354\()-0/$7�+IR$&)CE7�*,9$&�:6*�*,&8MGF�*�*,-f+.MNFQ-07E&�7b*g:�/�R�:�CER�+I[�:;*,+I-�/

�)­

Page 111: Practical Architectures for Survivable Systems and Networks (Phase

*,9�CE-0S$?�9�*E9$& � -0+I/c*�i#&8(g9$/�+I(�:6H � CE(g9$+5*,&)()*,S�CE&N| � i � ~ �Q%'&8(>*,+I-�/�kL3��@(8-0/$7�+IR$&)CE7�*,9$& � - � ��-c:�H�%'&8()S'�CE+5*BU � C�(g9$+.*E&8()*ES$CE&�| � ��% � ~ �#%'&8(>*,+.-0/�kL3 �s()-0/$7E+.R$&8C�7O*E9$& � -�+I/c* � +IC�Pa-�CE/$&N%'n ��n� \i � CE(g9$+5*,&8(>*,S$C�&| � � % � ~�%T*,:�/$R�:6CER$7�VL:6/$R$PQ-'-0D�| � %�VL~>3k�CE+5*,&)CE+�:2^{-0C�7E&)(8S$C�+.*BU :�C�&N()-0/$7E+.R$&8C�&8R+./%T&8()*E+I-0/h��X�+./$(8H.S$R$+./$?v*,9$&�O3�%a3 � &8F�:�Cb*,MG&8/c*O-�^ � &>�

^{&8/�7E&Li#CES�7�*,&)R�k�-0MGF$S�*E&8C�%'&8()S$CE+5*BU � J6:�H.S�:6*E+I-0/Nk�CE+5*,&)CE+�:N|ªi�k�% � k�~�XT*E9$& � S�CE-0FQ&�:�/�|ªnBi�% � k�~":6/$Rk<:�/�:6R$+�:�/�()-0S$/c*,&)CEF�:�Cb*,7_|�k�i�k<l � k�~>Xa:�/$R�*,9$&f/$&>A¨+./]*E&8C�/�:6*,+.-0/�:�H�k�-0MGMN-0/sk�C�+.*,&)CE+I:�3i�9$& "CE+.*E+I7�9�©s+./$+I7b*,C�U�-�^ � &)^{&8/�(8&�9�:�7Y&87b*g:�P$H.+I7�9$&8R�7�-0MN&"CE+.?0-0CE-�S$7Y7b*g:�/�R�:�CER�7�^{-0C�7E:6^{&)*BUc��(8CE+5*,+.(�:�H

7�UT7b*,&8MG7�� �c���TX �c��� �X¡:6H.*,9�-0S$?09�+.*<+I7�/$-�*�()HI&�:6C<*,-�A�9�:6*�&>=T*E&8/c*\*E9$&)U29�:�J0&O:�()*ES�:�HIH5UZPQ&8&)/�S$7�&8R�3nB/c*,&)CE/�:6*E+I-0/$:�H"()-'-�Fa&)C,:6*E+I-0/ +I7_+./$9$&)CE&8/c*EH.U :�R$+��G()S$H.*OF$CE-�P$HI&)MsX ()-0MGF$HI+.(�:6*E&8Rh&>J0&)/ ^{S�C�*,9�&8C@+./

*,9�&@(�:�7�&@-�^�()-0MNF�S�*,&)CL7�UT7b*,&8M 7�*,:�/$R�:�C�R$7�:�/�R�(8CE+5*,&)CE+�:qPcU�/�&8&8R�7 ^{-0C\*EC,:�/$7�Pa-�CER$&)C +I/c*,&)CE-0FQ&8CE:�P$+.H5�+.*BU�XWCE&8()+IF$C�-'(8:�H &>J�:6HIS�:6*E+I-0/�7 *,9�:6*�(8:�/ PQ&s|ª-0Cf+./$R$&8&)R�XWM@S$7b*OPQ&K~ 9$-�/$-0CE&)Rh+./jM_S$H.*E+IF$H.&_(8-�S$/c*,CE+.&87)XR$+5`«&)CE&8/c*�/$:6*,+.-0/�:�H�/$&)&8R$7�:6/$R�Fa&)CE()&8F�*E+I-0/$7v|ª&�3�?$35X -0/h*E9$&2C�&8HI&>J6:�/$(8&Z-�^�M@S$H5*,+IH.&)J�&8H�7E&)(8S$C�+.*BU0X�:6/$R9$-KA¨*E-2:�(g9$+.&)J�&O+5*�~>X¡:6/$R�7�-Z-0/�3"i�9$&8C�&@:�C�&O/�-Z&�:67�UvA�:KUT7L*E-Z:6(8(8-�MNF$H.+I7�9u7�S$(g9�()-'-0FQ&8CE:6*,+.-0/�X�P$S'*MN:�D]+I/$?�7�S$CE&�&)J�&8C�U�-0/$&O+I7<*g:6HID]+I/$?@A�+5*,9�&)J�&8CbU0-0/$&O&8H.7E&f+I7�&)7E7E&)/c*,+�:6H�3� 7 :�/�+I/c*,&)CE/�:;*,+I-�/�:�H#/$-0/$?0-KJ�&8CE/�MN&)/]*,:�H -0C�?c:�/$+.[�:6*E+I-0/«XQ*E9$&@nB/c*,&)CE/$&>* � /$?�+I/$&)&8CE+./$?2iY:�7ED�e�-0CE()&

|ªn � i�ed~N|ª9c*E*EF���m0m;A�A�Af3�+I&)*�^�3�-�CE?]~�9�:�7OPa&)&8/F�:6C�*,+.(8S$HI:�CEH5U�&>`«&)()*,+5J0&2+./ &)7�*,:�P$HI+.7E9$+./$?unB/]*E&8C�/$&)*�7b*g:�/T�R�:�C�R$78XOA�+.*,9o()-0/$7E+.R$&8CE:�P$H.&�&8MGF$9�:�7�+I7�-0/o+./]*E&8C�-0Fa&)C,:�P�+IHI+5*BUz:�/$Ro(g9�:�/$?�& ()-0/c*,C�-0H�3 |ªi�9$&�n � i�e7�*ECE-0/�?0H.Us^ª:KJ�-0CE7�-0FQ&8/p+I/c*E&8C�^ª:6(8&87)X�:6/$Rj*E-0HI&)C,:6*E&87�F$C�-0F$C�+I&)*,:�C�U�7�*,:�/$R�:�C�R$7f-0/$H5U�A�9$&)CE&G-0Fa&)/ 7b*g:�/T�R�:�C�R$7�:�HI7�-q&>='+I7b*�3�~�nB/s:�R$R�+.*,+.-0/�X'-�*,9$&)C�7�*g:6/$R�:�C�R$7�:�CE&f&8MG&8C�?0+I/�?@^{CE-0M�*E9$&O¥ Fa&)/ ��CE-�S$F|ª9c*�*,F���m0m;A�A�Af3�-0FQ&8/$?0C�-0S$F�3�-0C�?]~>Xc*,9�&<n ����� |ª9c*E*EF���m�m;A�A�Af3�+.&8&)&�3�-0CE?]~�X0*,9$& � 7E7�-'()+�:6*E+I-0/_^{-�C�k�-0MGF$S�*��+I/�?�| � k�©�~|ª9c*�*,F���m0m;A�A�Af3�:�(8Mu3�-0CE?]~�X :�/�Rr-�*,9$&)Cv-0CE?0:�/$+I[8:6*,+.-0/$7)3 V�-KA�&>J0&8C)XL*,9�&�n � i�e F$C�-'()&87E7vM_S$7�*vA"-0CED9�:�C�R$&8C�*,-_:�(g9$+I&>J0&\Pa&>*E*,&)C�F$C�-�*,-T(8-�HI7d*,9�:;*�&)/$(8-0MGF�:�7�7�MG-0CE&�-�^�*E9$&�7ES$CbJ'+5J6:�P$+IH.+.*BU�+.7E7�S$&87�:�R$R$C�&87E7�&8R+I/v*E9$+I7�C�&8FQ-0C�*83i�9$& ()&8Cb*,+��$(�:6*E+I-0/v:6/$RvHI+.(8&8/�7E+I/�?@-�^WF$C�-0?0C,:6MNMG&8C�7"+.7�:�HI7�-@PQ&8+I/�?@(8-0/�7E+IR�&8CE&)R�+I/27�-0MN&\(8+.CE(8H.&87�:67

:�/�:6F$F$CE-0:�(g9_*,-\7�*,:�/$R�:�C�R$+I[)+I/$?\R$&)J�&8H.-0Fa&)C 7ED]+.HIHI7)3Y%'&8&<C�&8()&8/c*dFQ-07E+5*,+I-�/OF�:6Fa&)CE7�PcU_l�:�C�/�:�7 ����£�1�$:6/$R \&)S$MN:�/$/��� � � ¡^{CE-0M *E9$&������0��n ����� nB/c*,&8C�/�:6*E+I-0/�:6HQk�-0/�^{&8C�&8/$()& -0/Zy�&)xTS�+ICE&)MN&)/c*,7 � /$?�+I/$&)&8CE+./$?$3

����� � �r�W���W�d����� ��� �������"�#�b���! �#���

V\+.7�*E-0CE+.(�:�H.H.U0X�C�&87E&8:�CE(g9z9�:�7�F$C�-¤JT+.R$&8Rz7E-0MG&�Fa-KA"&8Cb^{S$H�*,&8(g9�/$+Ix]S$&)7s^{-0Cv+./$(8C�&�:�7�+I/$? 7ES�C�JT+.J6:�P$+.HI+5*BU0XCE&)HI+I:�P$+IH.+.*BU�X :�/$R 7�&8(8S�CE+.*BU�X<:�H5*,9$-�S$?09�M@S$(g9 -�^�*,9$&vFQ-�*E&8/c*,+I:�HIH5U MG-07b*�J�:6HIS�:�P�HI&2C�&87E&8:�CE(g9 9�:�7q/$-6*^{-0S$/�RG+5*,7#A<:�U�+./]*E-�(8-0MGMG&8CE()+�:�H.H.Uf:�J6:�+.H�:�P$H.&"FQ&8C�7E-0/$:�H$(8-�MNF$S'*,&8C�F$CE-TR$S$(>*,78XT:�/�R�-0/$H.UO-T(8(�:67E+I-�/�:�HIH5U+I/c*E-�(8-0MGF$S�*E&8C@7bUT7�*,&)MN7)3�%'&)CE+.-0S$7@C�&87E&8:�CE(g9 +I7O7�*E+IHIH�/$&)&8R$&)R *E-p:�R$R$C�&87E7�7�-0MG&2-�^�*,9$&ZCE&8MN:�+./$+I/$?R$& ��(8+.&8/$()+I&87)3

2 e¡:�S�H.*�*,-0H.&8C,:6/$(8&\+I7�: �$&8HIRv+./ZA�9$+.(g92*,9$&)CE& +.7<&>=T*,&)/$7E+5J0&f:�/�RvR$+.J�&8CE7�&�CE&)7E&�:6CE(g9�X�MN:�/cU2:67EFQ&8()*E7-6^QA�9�+I(g9q9�:�J0&�^{-0S$/�Rq*E9$&8+.C A<:�U�+./c*,-�(8-�MNMG-0/@F$CE:�()*E+I()&�3�%'S�(8(8&)7E7b^{S$H¡&>=�:�MGF$HI&)7d+I/$()HIS$R$&<:�H.*E&8Cb�/$:6*,+5J0&�/$&>*BA�-0C�D�CE-0S'*,+I/�?$X�CE&)R$S$/$R$:�/c*OR$:6*g:v7E+5*,&)78X�^ª:�S$H5*�R$&)*E&8(>*,+I-�/ :6/$RpCE&8()-KJ0&8CbU0X�:�S�*,-�MZ:6*E+I(C�&)*EC�U�+./�F$CE-T(8&)7E7E+./$? :�/$R (8-0MGM@S$/�+I(�:;*,+I-�/$78X�:�/�R§&)CECE-�Cb�B()-0CEC�&8(>*,+I/�?�(8-TR$+I/$?p+./*,C,:6/$7EMG+I7�7E+I-�/:6/$R�7�*,-�C,:�?0&63

2 %T&8(8S�CE+.*BU C�&87�&�:�C�(g9r+I7G:jMG-0C�&sR$+��G(8S$H5*N+.7E7�S$&�3 ©uS$(g9rF�:�7b*ZC�&87E&8:�CE(g9�9�:�7GPa&)&8/�R$&>J0-�*E&8R�*E-S�/$CE&8:�HI+.7�*,+.(2:�F�F$CE-c:6(g9$&87)3 � -0C�D-0/ M@S$H5*,+.HI&)J�&8H�7E&)(8S$C�+.*BU�9�:67G9$:�R HI+.*�*,H.&NC�&�:�H�+.MNF�:6()*�X ^{-�C�:

��

Page 112: Practical Architectures for Survivable Systems and Networks (Phase

J6:�C�+I&>*BU2-�^YCE&8:�7E-0/�78X�-0/$&�-6^YA�9$+.(g9s+.7<*,9�:;*�*,9$&O©�¬#%2(8-0/�(8&8F'*L9�:67�/$-�*�Pa&)&8/�A�+IR$&)H.UZ:�(8()&8F�*E&8R-�S�*,7�+IR$&2-6^ � - � � &8+.*E9$&8C�+./*,9$&v()-0MGMN&)CE(8+I:�H�7�UT7�*E&8M :�/$R /$&>*BA�-�CED]+I/$?jMN:�+I/$7b*,C�&�:�MG78X -�CPcU�S$7E&)Cv(8-0MGM@S$/$+5*,+.&8783 � 7v:(8-�/$7E&)xTS�&8/$()&�X�MN:�/cU � - � 7bUT7�*,&)MN7�7b*,+IH.H\C�S$/r7�UT7b*,&8M��B9�+I?09�3%T+IMG+IH�:6CEH.U�X'FQ-�*E&8/c*,+I:�HIH5Uv+IMGFa-�C�*g:6/]*�C�&87�&�:�C�(g9�-0/�(�:6F�:�P$+.HI+.*BUc��P�:�7E&)Rs7bUT7�*,&)M :6CE(g9$+5*,&8(>*,S$C�&87�:6/$R9$:�CER�A�:�C�&>�B&)/�^{-0C�(8&8RuR$-0MN:�+./27�*ECES$(>*,S$C�&87�9�:�7�CE&)MZ:6+I/$&)RvH�:�C�?0&8H5UNS�/$+IMGF$HI&)MN&)/c*,&8Rv+./v(8-0MGMG&8Cb�()+�:�H�7�UT7�*E&8MG783 � J0&8/NA�9$&8/29$:�CER�A�:�C�&\R$-T&87�F$C�-¤JT+.R$&\7�-0MG&\R$-�MZ:�+./�7E&)F�:�C,:;*,+I-�/�Xc*,9$&�-0FQ&8C,:;*,+I/�?7bUT7�*,&)MN72*E&8/$R /$-6*2*,-�S$7�&�+.*83olY&8C�9�:�F$7vA"-0CE7b*�-�^O:�HIH}X<7E-�MN&�J�&8CbUrCE&8:�HI+.7�*,+.(�:6/$RrF$C,:6()*,+.(�:�HC�&87�&�:�C�(g9�9�:�7G7E+.MNF$H5U/$-6*G^{-�S$/$R�+5*,7@A�:�U§+./c*,-j?0&8/$&)C,:�H�F$CE:�()*E+I()&�3�e�-0Cq&�=$:6MNF$H.&�X�&>='(8&)HIH.&8/c*C�&87�&�:�C�(g9&)`a-0C�*E7O-�/:�S�*E9$&8/c*E+I(�:;*,+I-�/�X�:6(8(8&)7E7@()-0/c*,C�-0H�XY:�/$Rh:�(8()-0S$/c*g:�P�+IHI+5*BU�9�:�J�&27E+.MNF$H5U�/$-6*PQ&8&)/�:�R$-�F�*,&)R�+I/sMN-�7�*\(8-0MGMN&)CE()+�:�H�7bUT7�*,&)MN7)3 y�&8()-0MNMG&8/�R�:6*,+.-0/$7�^{-0C\:�(g9$+.&)JT+I/$?GM@S$H5*,+.HI&)J�&8H7�&8()S$CE+5*BUsR�&87EF�+.*,&�*,9$&@:�P$7E&)/$(8&_-�^dM@S$H5*,+.HI&)J�&8H �B7E&)(8S$C�&fS$7E&)C 7�UT7�*E&8MG7�:�/$Rs^{-0CL:6R$R$CE&)7E7�+I/$?27�-0MG&-6^Y*E9$&fFa-�*E&8/c*,+I:�HIH5UGCE&87�&�:�C�(g9'�BMG-�*E+.J6:6*,&)R�7�UT7�*E&8M +I7�7ES$&)7\:6CE&f(8-0/�7E+IR�&8CE&)Rs+./sk�9�:�F�*E&8CL�'3

2 %TS$C�JT+.J6:�P�+IHI+5*BUZC�&87�&8M@P$H.&87�*,9$&f*g:�+.H�*,CbU'+./$?q*,-NA�:�?G*,9$&�R$-0?$3�l#&8C�9�:�F$7\MN-07b*�+IMGFa-0Cb*g:�/c*�+./s*,9�&^{S'*,S$C�&OA�+IH.H�Pa&O7�UT7�*E&8M��B-0C�+I&)/]*E&8R�C�&87�&�:�C�(g9�&)`a-0C�*E7\*,9$:6*LF�+I(gD�S$F�*E9$&_(g9�:6HIHI&)/$?0&)7LF$S�*\^{-0C�*E9�+./*E9$+I7�CE&8FQ-0Cb*�Xc+I/c*E&8?0CE:6*,+./$?LC�&8HI+I:�P$+.HI+.*BU�X;^ª:6S$H.*Y*,-0H.&8C,:6/$(8&6Xc7E&8()S$CE+5*BU0X]FQ&8C�^{-�CEMN:�/$(8&6Xc:�/$Rq-�*E9$&8C JT+5*g:�HC�&8x]S$+.CE&8MG&8/c*E78X$A�+.*E9$+I/v*E9$&f-¤J�&8CE:�HIH�()-0/c*,&�='*\-�^Y?0&8/�&8C,:6HI+I[)&8R�7ES�C�JT+.J6:�P$+.HI+5*BU03

nB/O*E9$+I7#CE&)Fa-�C�*�|ª7�&8&�%T&8()*E+I-0/@�'3��0~>X;A�&"F$S$CE7�S$&"*E9$&�/$-�*,+.-0/�-�^�?0&)/$&8CE:�HI+.[8&8R�M@S$H5*,+.HI&)J�&8Hc7�S$C�JT+.J6:�P�+IHI+5*BU|�©s¬ � X +I/c*ECE-TR$S$(8&)R�+I/ %'&)()*E+I-0/r403��0~�*E9�:6*qR$CE:�A�7�-0/�F�:�7b*q&>='Fa&)CE+.&8/$()&�A�+5*,9�M@S�H.*,+.HI&>J0&8H�7E&)(8S$C�+.*BU�XM@S$H5*,+.HI&)J�&8H�+I/c*E&8?0C�+.*BU0X :�/$R�M@S$H5*,+.HI&)J�&8H�:�J6:�+IHI:�P$+IH.+.*BU�3 � &2R�-�*,9$+.7_/$-�*OA�+.*E9h*,9$&Z&>='Fa&)()*,:6*,+.-0/*,9�:;*7�UT7b*,&8M R$&)J�&8H.-0Fa&)CE7_A�+.HIHdC�&)A�CE+5*,&Z:�HIH *E9$&8+.C_7�UT7b*,&8MG78XdP�S�*@CE:6*,9$&)COA�+5*,9 *E9$&Z&�='Fa&)()*g:;*,+I-�/h*,9�:;*_*,9�&©�¬ � (8-0/�(8&8F'*LMG+I?09c*�F�CE-KJT+IR$&f7E-�MN&�S$7�&)^{S$H#:�C�(g9$+.*E&8(>*,S$CE:�H�+I/�7E+I?�9]*E783i�9$&�MG-0P$+IH.&>��(8-TR$&<F�:�CE:�R$+.?0M +.7�:�/q+IMGFa-0Cb*g:�/c* *E-0F$+.(<^{-0C ^{S�*,S�CE&�y � � X�A�+5*,9GCE&)7EFQ&8()*�*E-O7�&8(8S�CE+.*BU

:�/$RuCE&)HI+I:�P$+IH.+.*BU�3�|}%'&8&_%'&)()*,+.-0/s�'3�1$3�~y�&87E&8:�CE(g9wCE&)7ES$H5*,7u:�H.7E- 7ES$?�?0&87b*s7�-0MG&�R$C,:�MN:6*E+I(�(g9�:6/$?0&87u+I/r9�+I?09'��Fa&)C�^{-0C�MZ:6/$(8&�()-0MGF$S�*,+./$?$X

A�9$+.(g9+.^�F$CE-0FQ&8C�H.Uj:�F�F$HI+.&8Rh()-0S$H.RhCE&>J0&)CE7E&2*E9$&GC,:6*E9$&8CO/$&8?c:;*,+.J�&Z9$+.7�*E-0CE+.(�:�HdFQ&8C�7EFQ&8()*E+.J�&2/$-�*E&8R+./%'&)()*,+.-0/u1$3 �'3<e�-0C�&>=�:�MGF$H.&�X�*BA�-NCE&)(8&8/c*\7E-�^t*BA�:�C�&>�BP$:�7E&)R�&)`a-0C�*E7L:6CE&�+IHIH.S$7�*EC,:6*E+.J�& -�^d:qD]+I/$Ru-�^�/$&)A*,9�+I/$D]+I/�?�*E9�:6*Y(8-0S�HIR�Pa&dJ0&)C�U�PQ&8/$& ��(8+I:�H�3 � :�(g9_+.7Y:�R$+.`a&8C�&8/c*#/$&)A F$:�C,:�R�+I?0Mw*,9�:6*#9�:67Y()-0/$7E+.R$&8CE:�P$H.&FQ-�*,&)/]*E+�:�H«+I/v*,9$&fR$&>J0&)HI-0F$MG&8/c*�-�^Y9$+I?�9'�BFQ&8Cb^{-0CEMN:�/$()& 7�UT7�*E&8MG783

2 �f¬ � � 4 �0£ �F$CE-KJT+IR$&)7v:jJT+.C�*,S$:�HI+.[�:6*E+I-0/�-�^ M@S$H.*E+IF$C�-'()&87�7E+I/�?p*E9�:6*ZCE&8x]S$+.CE&)7N*,9�&�:�R$R�+.*,+.-0/ -�^:G^{&)A HI+I?�9]*BA"&8+.?09c* 7b*g:6*E&8MG&8/c*,7 *E-2(8-0/cJ�&8/c*,+.-0/�:�H F�CE-0?0CE:�MG78XaA�9�+I(g9�A�9$&)/ F$C�&8F$C�-'()&87�7E&8Rj+I/c*E-*E9$&u(8-0/cJ0&)/c*,+I-�/�:�H�H�:�/$?�S�:�?0& |�k�+./ *E9$&�(8:�7E&s-�^ *E9$&s&�='+I7�*E+I/$? ��¬ � +IMGF$HI&)MN&)/c*g:6*E+I-0/$7,~O&8/T�:6P$HI&f*,9$&OF�:�CE:�HIH.&8HI+.[8&)Ru&�='&8(8S'*,+I-�/�-�^ *E9$&_F$C�-0?0CE:�M +ICEC�&87�Fa&)()*,+5J0&O-�^ *,9�&_S$/$R�&8CEH5UT+I/$?N9�:�CER'A<:�C�&()-0/���?�S$C,:6*E+I-0/«3

2 %T+IMGF$HI&_©�:�S$R�& � 4¤�6£ F$C�-KJ'+.R$&87f:2MN:�(g9$+./$&>��+I/$R�&8FQ&8/$R$&)/c*�F$CE-�?0C,:�MGMG+I/$?NH�:�/$?�S�:�?0&OP�:�7E&)Rp-0/C�&)A�C�+.*,&fC�S$HI&)7�*E9�:6*�(�:6/sPQ&O()-0MGF$+IH.&8R2*,-G&>='&)(8S�*E&_-0/�:�CEP$+5*,CE:�C�UZ9�:�CER'A<:�C�&O()-0/���?�S$C,:6*E+I-0/�783�n�*+.7_:u7ES$P�7E&)*q-6^�©�:�S$R�&�����c��}X�A�9$+.(g9+I7O:�/&�='*E&8/$7�+.J�&2&8/cJT+IC�-0/$MG&8/c*@+./$(8H.S$R$+I/�?�:sJ�&8CbUhFQ-KA<�&)C�^{S$H�MG&)*,:�H�:6/$?0S�:�?�& *,9�:6*�7�&8C�J�&87L:�7L:6/s&�=�&)(8S�*,:�P$H.&O7�Fa&)(8+��$(�:6*E+I-0/uH�:�/�?0S�:�?0&f:6/$R�:qS$/$+5J0&)CE7,:6HR�&87E()CE+.F�*,+.-0/�H�:�/$?�S�:�?0&q|{9c*E*,F«��m0m;MZ:�S�R$&�3�(87�H�3�7ECE+}3�()-0MZ~>3

%'FQ&8()+���(�C�&8(8-�MNMG&8/$R$:6*,+.-0/$7L^{-0C\^{S�*,S$C�&qCE&87�&�:�C�(g9h:6/$RpR$&)J�&8HI-�F$MN&)/c*_:6CE&�?0+5J0&8/p+./j%'&8(>*,+I-�/ ¢'3��'3i�9$&Gy � � C�&8(8-�MNMG&8/$R$:6*,+.-0/$7�-�^�*,9�&NldC�&87E+.R$&8/c* ��7_k�-0MGMN+.7E7E+.-0/�-0/ k�C�+.*,+.(�:�HYnB/�^{C,:67�*,C�S$()*ES$CE&GldCE-;�*,&)()*E+I-0/u:�C�&�7�S$MGMZ:�C�+I[)&8Rv+I/s%'&)()*E+I-0/u¢�3��'3

���

Page 113: Practical Architectures for Survivable Systems and Networks (Phase

����� � � � � ���������� ��� � � ���������b� �

nB7E7�S$&87s7ES$(g9�:�7�CE&)HI+�:6P$+IH.+.*BU0X�7E&8()S$CE+5*BU0Xf:�/�Rw7bUT7�*,&)M 7ES$CbJ'+5J6:�P$+IH.+.*BU§/$&8&)Rw*E-§PQ&8()-0MG&p: F�:6C�*�-�^_:P$C�-c:�R$&)C�&8R$S$(8:6*,+.-0/�:�H�(8S$C�CE+I()S$HIS�M :�/$R +./$7�*E+.*,S'*,+I-�/�:�H�*,C,:6+I/$+./$?�F$C�-0?0C,:6MN7)3hi�9$&�7,:6MN&2+.7@*,C�S$&v-�^:�/ S$/$R$&)CE7�*,:�/$R$+./$?�-�^<JTS$H./$&8CE:�P$+.HI+.*E+I&)78X�*,9�CE&�:;*,78X :�/$RC�+I7ED]7)3si�9$&NR$&87�+IC�&8R :�S$R�+I&8/�(8&Z+./$(8H.S$R$&)7O/$-6*��S$7b*_F$C�-0?0CE:�MNMG&8C�7�:�/$Rh7bUT7�*,&)M R$&)J�&8HI-�Fa&)CE78X�P$S�*_:�HI7�-�:�R�MN+./$+I7b*,C,:;*,-0C�78XWHI&)?0+I7�H�:6*E-0CE7)X�7�UT7�*E&8M F$CE-6�(8S�CE&8MG&8/c* :�?0&8/c*E78X�:6/$R�&>J0&8/�F�CE-07�Fa&)()*,+5J0&OS$7E&)CE783\V\-KA"&)J�&8C8X«+I/s*E9$& ��/�:�HY:�/�:�H5UT7E+I7)X¡&8R$S$(8:6*,+.-0/�:6/$R*,CE:�+I/�+I/$?j(�:�/�/$-�*vPQ&�&)`a&8(>*,+5J0&�S$/�HI&87�72&)`a&8(>*,+5J0&�7�UT7b*,&8M 7E-0H.S�*,+.-0/$7Z:�CE&�:KJ6:�+.H�:�P�HI&v*,-PQ&�H.&�:�C�/$&8R�3� F�Fa&)/$R$+5= � -�S�*,H.+I/$&)7<(8-0S�CE7E&�(8S�CECE+.(8S$HI:_^{-0C�7ES�C�JT+.J6:�P$+.HI+5*BU03

����� ��� �����¡��!��#� ��� � � ���������� � � �

k�9�:�F'*,&8CN��-�^�*,9$&�C�&8FQ-0C�*q-�^�*,9�&sldC�&87E+.R$&8/c* ��7Zk�-0MGMN+.7E7E+.-0/-0/§k�C�+.*,+.(�:�H"nB/�^{C,:67�*,C�S$()*ES$CE&sldCE-�*E&8(��*,+.-0/ � 4K¢�1 �C�&8(8-�MNMG&8/$R�7O*,9�&2&87b*g:�P$H.+I7�9$MN&)/c*_-�^�7�-0MG&Z/$&>A -�CE?c:�/�+I[�:;*,+I-�/�:�Hd&8/c*E+.*,+.&87)3�n�*@+.7�A"-0Cb*,9CE&>JT+I&)A�+./$?�*,9$&)MsX�PQ&8(8:�S$7�&�*E9$&)UvPQ&�:6C�R�+ICE&)()*EH.U2-�/�*E9$&fF$CE-�P$HI&)MN7�-�^Y+I/'^{C,:�7b*,CES�()*,S�CE&f7ES$CbJT+.J6:�P$+.HI+.*BU�3

2 � / ��� " 1 ( ��� -� ( � #��� � � � � -��� " -� �%1 � � � � � � " 1�+./p*E9$& � 9$+5*,&qV\-�S$7E&�*,-�7�&8C�J�&Z:67*E9$&�^{-'(8:�H�FQ-0+I/c*<^{-�C�+I/�^{CE:�7�*ECES$(>*,S$C�&O:67E7ES�C,:�/$()&

2 � � - � ( � #��� ��� � � -��� " - ���O1 � � � ��� � " 1 � ( � � " � � -�^a(8-�CEFQ-0C,:6*E&�HI&�:6R$&8C�78X]7�*,:6*,&\:�/$RG?0-KJc�&)CE/$MG&8/c*�CE&)F$CE&)7E&)/]*,:6*,+5J0&)78Xa:�/$Rsk<:�P$+./$&)*�-��G(8&)CE7

2 � / � ��� � � -��� " - ���O1 � � � ��� � " 1 + ��� � ( � - ��� " 1

2 � ^{&)R$&8CE:�H�� 1 �� ��� 1�� " �j^{-�C�&�:�(g9s7E&8(>*,-0C2 � + 1 " - ( � � � � � � -��� " -� �%1 � � � � � � " 1 � (�( � � � � - ( �O^{-0C�&8:�(g9s+./�^{C,:67�*,C�S$()*ES$CE&2 � / � ��� ( � - � ( � +! J ��� � � � � � � #� � � � � �k1��'-e1 ��-6^ ?0-KJ0&)CE/$MG&8/c*L:�/$Rs+I/$R$S�7�*,CbU�CE&)F$CE&��7�&8/c*g:;*,+.J�&87

2 �#" � � � � � � 1��'- 1 �

i�9$+.7�7E&8&)MN7 *E-�CE&8F�CE&87�&8/c*_:2(8-0/$7�+IR$&)C,:�P�HI&�+I/�(8CE&8:�7E&�+./�*,9$&�+./$7�*E+.*ES�*,+.-0/�:�H.+I[�:;*,+I-�/u-6^<:�/p:6HICE&8:�R�U9$+.?09$H.UwP$S�CE&�:6S$(8CE:6*,+.(h7E+5*,S�:;*,+I-�/�Xf&87EFQ&8()+�:�H.H.Uw+I/z*,9�:6*�*,9$&�l�k�k�n�l 9$:�7�^{-T(8S$7�&8R�H�:6CE?0&)H.Uw-0/¨*,9�&7E-;�B(�:6HIHI&)Rh()CE+.*E+I(8:�H�/�:6*,+.-0/�:�H�+./�^{C,:�7b*,C�S$()*ES$CE&)7q:�/$R7�&8CE+.-0S$7�H.UjS$/$R$&)CEF$HI:�U0&8R�*E9$&2+IMGFQ-0C�*,:�/$(8&G-�^�*,9�&(8-�MNF$S'*,&8C��B()-0MNM_S$/$+I(8:6*,+.-0/G+I/�^{CE:�7�*ECES$(>*,S$C�&8783���&)C�UNHI+.*�*,H.&\+./Z*,9$& l"k�k�n�l§CE&8FQ-0Cb*<7ES�?0?0&87b*,7�*,9$:6*<*,9�&7ES�C�JT+.J6:�P$+.HI+5*BU0XK7E&)(8S$C�+.*BU�X0:�J6:�+IHI:�P$+IH.+.*BU�X8-0CWCE&)HI+I:�P$+IH.+.*BU�-�^T*,9$&�(8-�MNF$S'*,&8C��B()-0MNM_S$/$+I(8:6*,+.-0/�:�/�R_+I/'^{-0CEMN:;�*,+.-0/u+I/�^{CE:�7�*ECES$(>*,S$C�&87�A�-0S�HIR�?0:�+I/�7E+.?0/$+���(�:�/c*EH.U2^{C�-0M�*,9�&87E&_-0CE?c:6/$+I[8:6*,+.-0/�:�Ha&8/c*,+5*,+I&)783<nB/�:�R$R$+5*,+.-0/�X*,9�&8CE&�+I7�7b*,+IH.H$/$-O(8-0/$7b*,+5*,S$&)/$()Uq^{-0Cd*,9�&\/$-�/'� � - � /$-0/T� �O3%$a3 � ��-KJ'&8C�/$M(&8/*)�S�7+&8C�F$S$P�HI+-,6XT:�7�9�:�7�P.&/&8/F10'2-3*)4&)R�0�S5)�063OJ6:�C+2700S$7�08,9,�:67+2-063$7 �:273�,8H.S$R�273$?;2-3<),9�&�4K¢0¢0�;2-3<),95&>= � � � ��� ����� �.? ��� 7@)ES$R�U �������3nA3B)E9�&2M(&�:63cA�9�2.H-&�X�ldC+&87@2IR�&/3*)Nk�H-2-3*)+0'3h9�:67@C+&/,90'3$7�)42C),S5)+&8RD),95&vl�k�k�n�lE,9063�,9&)F5)�PcUD,)C+&�:F)42-3�?

:jk�C+2C)42-,8:�H<nA3�^{CE:�7@)ECES�,G),S$C@& � 7E7�S$C,:635,9&�¥ �(,/&|}k�n � ¥�~�X�:63$RH,8C@&�:I)+&8RJ),9�&K0��(,9&L0�^M),9�&u \:I)4270'3�:�Hk0800CER�273�:I)+00C�^N00C�$8&9,8S�C+27)BU�X nA3�^{CE:�7@)ECES�,G),S$C@&vldC+06)+&9,/)+2-0'3«X :63$R�k00S�3*)4&)Cb�Bi�&8C�C+00C@2I7�MsX#A�9�2-,g9hA;2.HIH�P1&C+&)7EF10'3$7@2IP$H7&@^N00Cf:vP$C+0c:6R CE:63$?'&�0�^"F100H-27,92-&)7�:63$RjF$C@00?0C,:6MN7 C@&8HI:I)4&)RO)+0L,)UTP.&)C@)+&8CEC@00C+2.7EMu3�nA3h:6R$R�25�)4270'3�X8),9�&�e �n�2.7&)7@)g:6P$H-2.7E9�273$?�:� L:F)42-063�:�HQnA3�^{C,:�7�),C�S�,/)ES$C+&�ldC+06)+&9,G)42-063uk&93*)4&)C_|ª \n�l�k�~�)40�,/00S�3*)4&)C

� �

Page 114: Practical Architectures for Survivable Systems and Networks (Phase

2-3�R�2.J82IR�S�:�HI7<:63$RK00CE?c:I3�2I[8:I)4270'3$7 ),9$:I)M,900MGM 2C) ,90�MNF$S )4&8C;,)C+2IM(&87)3 | $ &9&OldC+&)7+2IR5&93*)42I:�H � &9,/2I7+270'3 � 25�C+&/,/)+2.J'&)7�l ��� �c�;063�,/00S�3*)4&)C@)4&)CEC@00C+2.7EMo:63$ROl ��� � ����� � }X�:I2IM(&8R�:I)#C+&)R$S�,9273$?;),9�&�JTS$H-3�&)C,:�P52IH-2C)427&8783�~��3'^N00C@)ES�3�:I)+&8H.U�X*),9�& ��3 $Q3 ��0KJ'&8C@3$M(&93*)<9�:67�9�:�RZH-27)@),H7&�7ES�,/,9&87�7 2-3 &93*)427,92-3�?>,9&)C@),:62-3NMZ: �@0�C�,/00Mq�

M(&8C+,/2�:�H�R�&)J6&8H-0�F.&)CE7 )40fR�0<),9�&�C+2.?09*) ),9�273$? � 3�:�M(&8H5U0X')40�7+2.?'3�2�� ,�:63*)EH.U�2-3�,)C+&�:67+&;),9�&�7ES�C�J82.J6:�P�2.H-2C)BU0X7+&/,8S$C@27)BU�X�:63$R�C@&8H72�:�P�2.H-2C)BU 0�^ )E9�&92.CL7bU'7�)4&)MN7)3 i�9�:I)�7�9�00C�)4,90�M 273$?NMN:�UuS$H7)+2IMN:I)4&)H.UvP1&�)E9�&_H72IM(27)4273$?^ª:6,G)400C � R�&)7EF�2C)4&�),95&�9500F.&>^{S$H-35&87E7M&>='F$C@&87�7+&8R 2-3�7+00M(&�0�^�),9�&fC@&9,90�MNM(&93$R$:I)4270'3$7 0�^ 00S$C�C@&8F100C@)83� H.7+0$X�S�3�^N00C�),S�3�:F)4&8H5U0X ),95&���0KJ'&)C+3$M(&93*)\7+&9&)M 273$?0H5Uv9�:�7;3�06)�9�:6RsM@S5,g9�7ES5,9,9&)7E7 273u:6,g9�2-&>J82-3$?N:

M(2-3�2.MZ:�HYH-&>J'&8H�0�^ ,/00MNF1&/)+&93�,/& 273:�J'0'2.R�2-3�?s7@&9,8S�C+27)BU C+2.7ED]7v|ª:�7>&>J82IR�&/3�,9&)R�P]U � &)F$S5)BUD$ &9,)C+&/),:�C�U0�^ � &>^N&93$7@& � 009�3 V\:�MGC+&(,�:�H.H-2-3�?L)E9�&�k�H70¤J6&8C�R�:�H-&ND 2IR$7 � ,/0 00D]P10 0�D :F)+)g:I,gDO)E9�& �bM 007�)�00C�?c:63�2.[9&)R:63$R�7bU'7�)4&)MZ:I)+2-, )E9�&fl &/3*)g:�?'063s9�:67�7+&9&/3 )40qR�:I)+&�� � 7@&9&�),9�&fy;2I7�D]7�e 0�CES$MuXTJ600HIS�M &@4�¢�X52.7E7ES5&f�0�|ª9*)@),F���m0mI,8:I),H7&87E7)3 35,8H�3�:6,63�S$D'm�y;2I7�D]7gm'4K¢'3��0�'3�9*),MGHt~�00C�2-3hR5&�:�H72-3$?�A;27)E9B,90�MNF$S )4&8CO7�UT7@)+&8MG7q:I)_:�HIH\|}:67&)J82.R�&93�,/&8R P]U ),9�&q9]S$?'& &)`.00C�)�)40�7ES$C�M 0�S�3*)�),9�&����6� ,g9�:�H.H-&/3$?'& � 7@&9&Zk0'3$?0C@&87E7�MZ:I3D$8)+&8F$95&93V�0�C+3���7 �f����C+&)F.00C�)�,8:�CER«X�9*)+)EF���m�m;A�A�Af3�9500S$7+&63�?60¤J�m6C@&)^N00C�M2m;?0M 2C)�m;U��6D'mI273$R�&�=«3�9*),MuX6A�9�27,g9_A�:�7�S$FT�R�:I)+&8Rvx]S�:�C�)4&)CEH.Uq^N00C"7+&>J'&8CE:�H«U6&�:�C�7<F$C+2700C�)+0 ���6�¦:I3$R27E950¤A�&8R�7�H-0KAwF$C+00?�C+&87�7�^N00C":_H-063$?>)42.M &�~>3Yn )2I7 :�9]S$?6&(,g9$:�HIH7&93$?'&_M &)C+&8H5U�?6&/)+)+2-3$? ,/00MGF.&G)4&935,9&qH-&>J'&8H.7�2-3�7@&9,8S�C+27)BU�S$F )40�),95&GH7&)J6&8HI7L7ES$?0?6&87@)+&8R2-3 � �� ���� ���� = � � � ��� � = �� � ����� � }3e�S$C@)E9�&8C 273�^N00C�MZ:I)+2-0'3�0'3 � &)PO7@27)4&)7�^N00C�7+00M(& 0�^8),9�&�:�P10KJ'& 00C�?c:63�2.[�:I)+2-0'3$7�:63$Rf^N00C!),9�&"k<:�C@3�&8?62-&>�© &)HIH-063 $80�^ )BA<:6C+& � 3$?62-3�&/&8C+273$?qnA3$7@)+27)ES5)4& ��7 k00MNF�S5)4&)C � M(&8C�?'&93�,>UsyM&)7EF10'3$7+&Oi &8:�M |�k � y�i�~�:�C@&?'25J'&93K2-3 � F$F.&/3$R�2 = � | $ 00M(&f �06)+&)A�00C@)E9cUuyM&>^N&8C+&/3�,9&)7g~�:I) ),95& &/3$R 06^ )E9�2I7�C@&8F100C@)83

� �

Page 115: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

������� ��������� � ��� �"!#���$�

%'& &�,)(+*,*@&93*).-0/ &21 243�)4273+5 &)6879-:(;7I)4270'3 ,)*+2C)4&<*@2=7?>@*,79A(&)B�0C*,DE379*@&�3�06)F/6&/)<,909A?G+*@& & &/3+3+206'&)-:/�3H(�27).79I+--&>N0C*�&)6879-:(;7I)4273+5 & 245 & -0/J3,(K*H682:6879I+-7&L3M/N3�)4&)A?3�7I3+O�3�&G)PB0C*HDE3<QSRT6'&93UB;2C) & *@&<5V78*,O>)+0W3+&/,<(+*@27)P/XIV/>2C).3+&)-:>ZY) & & &[1 243@)+2-3+5;,)*+27)+&<*@2=7'79*@& 273�,909A?G+-7&/)+&�763+O 2-3;78O�&<\E(;7I)+&9Q^]A3U79OKO�27)+2-0'3_Y/) & &)*+& 243`79-:A 0C3�) 3�0M&21NG1&<*+27&93�,/&2-3 &)6879-:(;7I)4273+5a3H/b3@)+&<Ac3 & 7d682-3+5e7 ,/0C-4-7&9,/)+2-0'3O09> 2-3+O�&)G.&/3+O�&/3 )>,<*@27)4&)*+247L) & 7I)XA 2:5 & )�,/0'3*).*@24I+(5)+&()+03,(K*H682:6879I�2:--2C)P/CYf763+O�) & &K2-3*)4&)*.76,G)42-063+3g78A 0'3K5hO52:i.&<*+&/3*)�,<*@27)+&<*+247�3,(+I+3@&/),3j79*+&k79-:A 0C3�)l(�3�&[1KGK--0C*@&<O0C(5),3+2:O�&�09> ) & &�,9063 )+&218) 09> ) & 243X*+&<G10C*�)dQ�mM&)6'&)*@) & &<-7&<3,3)YL7n560 0bO�3@&/) 09>o3@&9,<(K*+27)P/ ,<*@27)+&<*+247jp 20> 27)&21 2:3@)4&)Ojp B�0C(+-:OkI1&J6'&)*H/j6879-4(+79I+--&8Q

%'& 2:3S3@&9,G)42-063 ,/0'3+3+2:O�&<*H3 ) & &M&<A(&<*,562-3+5Xq0CAcA 063gqL*@27)+&<*+247�&)i.0C*@)<YEB & 2-, & 2:3S7I)+)+&<AcG5)4273+5 )40 0r6'&<*Zs,909A &'A?763V/�09>1) & &oO�& � ,927&93�,/2-&)3�09>.27),3�G+*+&/,<(+*H3+0C*H3<Y8) & &ut 0Vt % *,(+3�)4&<Ovq0CAcG+(5)4&)*�$ &9,)(+*+2C)P/lRT6978-4(;7ws)4270'3xqL*+27)+&<*@2=7oyz7I2-3EI.0rB�3+&<*@2-&)3'{ &8Q|5KQ:Y ) & & % q $KRSq~}|�8�C�8��Y % mu]S}|�9�N�)��YC763+O % tF]�}��9�V�w�=�2Y ) & &LR�(+*@0CG.&<763] % $KRSq�}��C�8��Y�763+O ) & &xq�7I3;79O�24763kq % q��SRSq�}��C�8��Q

%'& & &26'0C-06 273+5�q0CAcA 063cqL*+27)+&<*@2=7WO�08,<(KA &/3 ) & 793�I.&/&93c(�3+O�&)*,5'062-3+5�&[1 )+&93+3@2:66&z*@&)682-&2BYVG+*+&)G;79*.7�s)409*H/ )+0�I.&/2-3+5�3H(+I+A(27)@)4&<Oa783o763a]�$+�#3�)�763+O+79*,O_Q�$ &/& & )+).G����C�F,<3,*@,9Q 3�243�)dQ�5'0r6K�I,9,>N0C*) & &J-=7I)+&<3�)'O+*.7w> )O�08,<(+A(&93*),3o763+OaG+*+095C*+&)3,3 )40rBL79*,OL&)3@)�78I+--2:3 & 273+5>) & &�q0CA?A(0'3aqL*@27)+&<*+247KQo{�� &<*,3@2-0'3��bQ:�FBL793'G10C3@)+&<O�K� � 763E(;79*M/��9�C�9�KQ��

� 3V/"3+&G)�09>o*+&)\E(�24*@&<A(&93*).3)Y�763+OD273+O�&9&)O�763V/�56&93�&)*+2-,n{�79IK3@).*,76,/)��X3H/b3�)4&<Ac3l79*@, & 27)+&9,/),(+*+&8Y�AU(+3�)3�06) 0�66&<*H-:/�,/0'3+3�).*.7I2-3 ) & & 24AcG+--&)A &/3 ).7I)4270'3+3 09>^3H/b3@)+&<Ac3;2-3*)4&/3+O�&<O )+0�3.7I)+243H>�/ ) & 093+&J*+&)\E(�24*@&<A(&93*).3)Q%'& 2:3M2:3u763 273 & &)*+&93*)uO;763K5'&<*;2-3 ) & & % q $NRfqWY�I+(5)u-7&<3,3o3@0 2-3 ) & &<06) & &)*;,<*+2C)4&)*+2=7�I1&9,<79(+3+&<) & &)/�79*@&>@*.78A &2B0C*HDE3x>N0C*�&26978-4(;7I)+2-0'3"*.7I) & &<* ) & 7I3�G+*+&)3+,<*@24G5)+2:66&j*+&<\E(�2:*+&)A &/3 ),3<Q�]A3�79O+O527)4270'3_Y�) & &v] % $NRfq763+Ohq % q���RSqE&2i &/,/)4206'&)-:/nO5243@)+2-3+59(�243 & >@(�3�,G)42-063;79-$*@&<\E(�2:*+&<A(&93*),3F>@*+0CA 793,3H(+*.7I3�,9&l*+&)\E(�24*@&<A(&93*).3)Y763+OL) & 7I)o(+3+&2>@(+-`O�243�)4273�,/)+2-0'3 & 783uI1&9&/3 ,/0'3*)4273b(5&<OK2-3 ) & &Xq0CAcA(0'3�qL*+2C)4&<*@2=7KQ

%'& &)*+&�243F79-43@0j7v3+&)*+2-09(+3JO;763+56&<* 09>S(�3KO�&<*@,90'3+3�).*,762-3�273+5�) & &U*+&)3,(+-C)42-3K5j3H/b3@)+&<Ac3763+OO3�&/)PB�0C*HDb3)Q¡ 0C* &[1K79A?GK--&9Y.) & &�yu76273bI10rB#3+&<*@2-&)3 09> ).*H(+3@)+&<ONs¢3H/b3@)+&<A ,)*+27)+&<*@2=7gA?7d/ 0r6'&)*+,/0'3+3@),*.76273O24AcG+--&)A &/3 ).7ws)4270'3+3'B;27) & *@&<3HG.&/,/) )+0() & &�I+(�3+O+-72-3+5 09>�,<*@27)4&)*+247 &)--&)A &/3 ),3W7F)W7lG;79*�)427,<(+-479* &)6879-:(;7I)4270'3a--&26'&<-f{N&9Q�5+Q:Y� �9Y8£L�KYw£'�NYw£W�CY8q'�C�[YwIK(5)^79-43@0'(�3+O�&)*+,/0'3+3@),*.76273 ) & & 24AcG+-7&<A(&93*)�7I)+2-0'3K3¤B;27) & *+&)3,G1&9,/)�)+0uA?763V/ 0I) & &)*,<*@27)+&<*+247K&)--&)A &/3 ),3�) & 7I)�78*+& 09A 2C)+)4&)O�p *+&)-=7I)+2-3+5L)40 3�&/)PB�0C*,D 273+5+Y�79G+GK--2-,<7I)4270'3�3+&/,<(+*@27)P/CY�A(0bO�&<*@379(5) & &93*)+2-,d7F)42-063~{ &8Q|5KQ:YT(K3+2-3K5 0'3�&[s )+24A(&()+0CD6&/3+3�2-3K3@)4&<79OD09>��K1 &<O�*+&)(+3.78I+--&?G;793,3MB09*,O+3.�2Y�>¥79(+-C)�)+0C-0s&<*,763�,/&9Y�*@&<-72=79I�2:--2C)P/CY+*@&d79-¦s )42:A &JG1&<*M>N0C*,A?763�,/&9Y12-3*)4&)*+0CG1&<*,79I�2:--27)P/9Y;*+&)(+3.79I524--2C)P/CY�3+09> )PBL79*@&�&93+562-3�&/&<*+273+5+Y763+O ) & &UO5&)6'&)--0CGKA &/3 )FG+*+08,9&)3,3<Y.)40�3;78A &'§H(+3@)F7?>N&)BQ %'& &<3+&l783,G1&9,/),379*+&x79I+3@0C-4(5)+&<-0/j>@(�3+O;79A(&93bs)�78- )+0 ) & &g3H(�,9,/&<3,3M>@(+-'G+*@0 ,)(+*+&)A &/3 )U763+O"O�&)66&<--09G+A &/3*)�09>'3H(�27).79I+-7&?3M/N3�)4&)A?3�7I3+OD3�&G)PB0C*HDE3>) & 7F),d7I3e3.7F)4243M>�/a3@),*+2-3K5'&93*)u*+&)\b(524*+&)A &/3*).3<QM$824AcG+-:/v79O & &)*+2-3K5()+0c66&<*H/k3,(KG.&)* � ,/2=79-`I+(5)W79-:--&<56&<O+-0/gO�& � 3�2¦s

� �

Page 116: Practical Architectures for Survivable Systems and Networks (Phase

)4206'&�5'&/3�&<*@2-,U*@&<\E(�2:*+&<A(&93*),3X7I3+O ,<*@27)4&)*+247�{ �F*.7I3+5'&l£080CD�Y y;&<Oh£080CD�Y`763+O 06) & &<*H3��2Y GK*+08,<(+*@&<A(&93*),9080CDEI10 0CDE3)Y`763+O"q & 2-35&<3+&�A(&93E(+3J>N0C*W3H/b3@)+&<A ,/0'3��;5C(K*.7I)+2-0'3 2:3FO�080CA &)O )40v>¥762:-4(+*@&9Q]A3h79O+O�2C)4270'3_YO�&)3,G�2C)4&) & & &9350C*,A(0C(+3�G+*+0C-72:>N&)*.7I)+2-0'3 09> ) & &'yz7I2-3EI.0rB�3@&<*+27&<3 273xAU(K-7)42C).(+O52-3�0C(K3 ,/0C--0C*H3<YF) & & % q $NRfq243�2-3*).*@2-3+3@2-,<79-4-0/ 2-3�,/0CAcG+--&G)4&9Y^>N0C*U7e6879*@2-&G)P/ 08>o*+&d783+0'3+3)Q�� ¡ 09*�&[1+78A?G+-7&9Y 2C)xO�&<79-43xG+*+2:Ag79*@24-0/eB;27) &,9063��;O�&/3 )+2=79-727)P/ 273 ,/&93*).*,79--2 � &)Ok3M/N3�)4&)A?3U{@>¥762:--2-3K5>)40cD6&/&<G�(+G�B;27) & ) & &X-4793@)oO�&/,d79O5&>09>$G+*+0C59*+&<3H3 273O�2:3@).*@24I+( )4&<O�3M/N3�)4&)A?3�763+OO3�&G)PB09*,D6&)O 3H/b3�)4&<Ac3<Y�763+OO3�0I)�79O�&<\E(;7F)4&<-0/ ).*@&d7I)+2-3+5 273*)4&<59*+27)P/e763+OO) & &G+*@&)6'&/3*)42-063�09> % *+0w§,7I3 & 0C*,3@&<3l763+OJ06) & &<*�G1&<3�)lG+*+095C*.79Ac3��[Q"] )�243UA(0'3�0C-727) & 2-,8Y�2-3D) & 7I)�2C)�-4(KA?G+3)4095'&/) & &<*U>@(�35,/)4270'3;79-727)P/�763+O�793H3,(+*,763�,9&8Y'763+O�B;2C) & 273 >@(�3�,/)+2-0'3+79--2C)P/B,)*+27)+&<*@2=7e-:(+A?GK3�)40C5'&G) & &)*�*+&[s\E(�24*@&<A(&93*).3�) & 7I)a78*+&nA(0C*+&e*.7I)+2-0'3;78-4-:/ ),*+&<7I)4&)O~3+0CA(&)B & 7F)L2-3+O�&)G.&/3+O�&/3 ),-:/9Q ¡ 0C* &[1K79A?GK--&9Y;) & &3�06)+2-0'3�08> �K1 &)O?G;783,3HB�0C*HO+3fO50 &)3 3506)�Ag78D6&'AU(�, & 3+&/3+3+&M2-3�3M/b3@)4&)A?3 ) & 7I)�O�&<A?763+O & 2:5 & 793H3,(+*,763�,9&8QqL*H/bG5)+0C5C*,79G & / 243I;793@2-,d78-4-:/ 245'350C*+&)O_Q %'& & % q $KRSq O�08&<3 3�06)x79O�&<\E(;7F)4&<-0/O,90'35,9&<*@3�79G+GK--2-,<7I)4270'3+3763+Ol3M/N3�)4&)A?3 ,/0'3��;5C(K*+&<O(0C(5) 09>106) & &)*�3H/b3@)+&<Ac3<YE3@),*+&)3,3+273+5G+*+2:Ag78*+24-0/ ).*H(+3@)+&<Oc3H/b3@)+&<A ,/0CAcG.0'35&93*).3)Q] )z79-43@0�)P/bG�2-,<79-4-0/ 2:5'3�0C*@&<3'3,(K*H682:6879I�2:--2C)P/CYK*@&<-72=79I�2:--2C)P/CYV>¥79(+-C) )40C-7&<*,763�,9&8Y+G1&<*H>N09*,A?763�,9&8Y 2-3*)4&)*+0CG1&<*,79I�2:-0s27)P/9YE*+&d78-0s )+24A(&'*+&)\b(524*+&)A &/3*).3<Yb3H/b3�)4&<A�&93K5'2-3�&/&<*@2-3+5x763+Og3@09> )PBL79*+&�&93+5'273�&9&)*+273+5+YE3H/b3@)+&<A�0CG1&<*.7F)42-063+3<Y763+OjA?763V/ 06) & &)* 243H3,(�&)3 ) & 7I)'79*+& &)3,3@&93*)42479- )40�) & &FO�&26'&)--0CG+A(&93*)u763KO ,90'3��+5C(+*.7F)42-063 09>`3,(+*M682:6879I+-7&3H/b3�)4&<Ac3z763+OK3�&/)PB�0C*,DE3)Q

%'& &�O5&<3+2:*+&)+0FI1&�79I+-7&�)+0 ,90'3 �;5C(+*@& ,<*@27)427,d79-E3M/N3�)4&)A?3 0C( ) 09> 09i�s ) & &2s¢3 & &)-:> ,/0CA?G10'3�&/3*).3�763KO�G;79*Ms)427,<(+-479*,-0/ 09i�s ) & &2s¢3 & &)-:>;3@09> )PBL79*+&�243�,90CAcA &/3+O;79IK--&9YwI+(5)$-=79*H5'&<-0/7u>¥7I3 ).793H/9Q�q0CAcA(&<*+,/2=79-:-:/W7d697I24-=78I+--&2-3N>@*.793�).*,(5,/).(K*+&(,90CAcG.063�&93*).3g{ 09G.&)*.7I)+2-3+5�3H/b3@)+&<Ac3<YTO+7I)�79I+793+&cAg7I3;795'&)A &/3 )�3M/N3�)4&)A?3)Y 3�&/)PB�0C*HD8273+53+08> )PB�79*@&9YN763+O?79G+G+-72-,<7I)4270'3U3+08> )PB�79*@&r��79*+& )P/bG�27,d79-:-:/�3�06)f79I+-7& )40>@(+-��;-:-K3�).*+273+5'&/3 )S*@&<\E(�24*@&<A(&93*).3)Q�]A33+09A & ,d783+&<3�&218)4&/3+3+206'& ,<(+3�)40CA(2 � 7I)4270'3 243*+&)\E(�24*@&<O_Y�763+O 243J3@)+24-:- 2-3;78O�&<\E(;7I)+&9Q ¡ (K*@) & &<*,A(0C*@&9Y�,90'3bs3+2:O�&<*,79I+-7&>&21NG1&<*�)4243@&�243z*+&)\b(524*+&)O )40 0CG.&)*.7I)+&U763KO�Ag76273*)�76273K) & &x*@&<3,(K-7)4273+5v3M/N3�)4&)A?3)Q %'& &�,9063�,9&)G5)09>�).(+*@3NsPDI&)/a3M/N3�)4&)A?3u3.7I)+243M>�/ 273+5 &218).*@&<A(&<-0/�,909A?G+-7&21L,)*+2C)42-,<79-�*@&<\E(�2:*+&<A(&93*),3M2:3'(�3+*@&d79-7243@)+2-,8Q

� & 7I) 243�3�&9&)O�&<OO2-3K) & &X>@(5).(+*@&�243zA 09*+&>&2i 09*@).3W7624A(&<O 3�06)F7I)�,9080CDEI10 0CDE3zI+(5)J*,7I) & &)*F7I) ,90'3bs3@),*,(�,G)4206'&�O�0 ,)(+A(&93*)�7I)+2-0'3 08>�B�0C*,DI&<O &[1K79A?GK--&<3'GK*+0r6824O�273+5�) & &J>N0C-:--0rB;2-3+5K�

2 t &G)�762:--&)O�>@(53�,/)+2-0'3;78-'*+&<\E(�2:*+&)A &/3 ),3 &/3�,90CAcG;793H3+273+5�*@&d79-7243@)+2-,<79-4-0/B,/0CA?GK--&/)+&a3+&/),3�09>W*+&<\E(�2:*+&[sA(&93*),3f*@&<--&268763*)�)+0X3H(+*H682:6879I524--2C)P/�{ &8Q|5KQ:Yb3+&/,<(+*@27)P/CYb*+&)--2479I�24-727)P/9YC763+Oc>¥79(+-C) )+0C--&)*.7635,9&r� ) & 7I) ,90C(+-:OI1&J(+3@&<Ok>N09*o7�B;2:O�&*.763K5'&<09>$GK*+08,<(+*@&<A(&93*).3)Q

2 t &G)�762:--&)O 5C(524O;7635,9& 063 & 0rB )40 & 763+O+-7& ) & & 2-3*)+&<*.7I,/)4270'3+3g79A 063+5 ) & &k6879*@2-0C(+3(,9063+3@)+27).(5&93*)3H(+I5)+&93+O�&)Oe*@&<\E(�24*@&<A(&93*).3o>N0C*'3H(+*H682:6879I524--2C)P/CQ

2 t &)3+2:5'3�>@*,79A(&)B�0C*,DE3?763+O 78-7)4&)*+3;7F)42:66&j>¥79A 2:--27&<3�09>W--0C562-,d78-'79*+, & 27)4&/,/),(+*+&)3v763+O 79*+, & 27)4&/,/),(+*.79-3�).*H(�,/),(+*+&)3L) & 7I)j>¥76,/24-727)�7F)4& ) & & ,909A?G10C3+2C)4270'3 09>X3,(+*M682:6879I+-7&�3H/b3@)+&<A 763+O 3�&G)PB09*,DE3 09(5)L09>3H(+I+3M/N3�)4&)A?3)Q

2�� (�2:O;763�,/& 0'35'080NOF3M/b3@)4&)A &93+562-3�&/&<*+273+5o763+O3@09> )PB�78*+& &93+562-3�&/&<*+273+5'G+*,76,/)+2-,9&8Y�763+OJ>¥79*ZsP*+&<76, & 273+578G+G+*+0C76, & &<3 )+0�BL79*HOe3H/b3�)4&<A O5&)6'&)--0CGKA &/3 )<Q

2�� (�2:O;763�,/&�0'3a5'0 0bOaG+*+08,<(K*+&<A(&93*)uG+*,76,/)+2-,9&8Q2 ]PO5&93*)42�� ,d7I)+2-0'3 08> 273*)4&<*@0CG1&<*.78I+--&FO5&)6'&)--0CGKA &/3 )M&/3E682:*+0'3+A(&93*),3z7I3+OL,90'3+3�).*H(�,/)+2:6'&�)+0 0C-:3<Q��M0rB�s&26'&)*<YM27)vAx(+3@)aI1&n*+&/,90C563�2 � &<O ) & 7I)�)4080C-:3v79*@& 3�06)v7 G;763;76,/&d7�� ) & &92:*v(+3@&�Ag7d/�2-3 >¥76,G)jI1&,/0C(�3*)4&)*,G+*@0NOK(�,/)+2:6'&8Q

3 j�;rqW;�DHGMLS=!DH6 ><6���[C;!8:UlV XZ;![CIJG� \ ^�W`Ma GCn� ]69L9L9698� YGMDH; \ �A`A`.a GMDH;�8f>H69L9L d��AD<><5 =���C8<69nC;!DH6���CbOU0;!= GM[78H;�IJGlV��MN >H57;���G�d�8 6�T>H5C;4�� j�h�� GMDH;Z8<><69L9L�DH;���;!=r>H;!n�6��;rqMGML9[�G.>H;!n�8<V�8<><;!I�8i>��ln�G!V���N [CDf>H57;�D<I �ADH;AbW8��AI�;!�MNe><5C;ZECD��AUCL9;!I�8OdZ6 ><5�>H57; 4�� j�h�� =�G�U0;ZDH;!ECL969=�G.>H;!n�UlVECD"�M>H;!=r>H6���pECD��#�L9;!8�6��><5C;$�%�AI�I ��&� DH6 ><;�D<6KG7v

� �

Page 117: Practical Architectures for Survivable Systems and Networks (Phase

2�� (�2:O;763�,/&�0'3�76, & 2-&2682-3+5 2-3*)+&<*+,/0'3�3�&/,/)+2:6827)P/a7I3+Ok*@&<(+3,79I�2:--27)P/9Q2 ]PO5&93*)42�� ,d7I)+2-0'3 09>�>@(�3+O+79A &/3*)�79-;5V78G+3 2-3�) & &;&[152:3@)+2-3+53@).763+O;78*,O+3)YK763KO 2:O�&93*)42�� ,d7F)42-063�09>¤B & 2-, &3�)�763KO;79*,OK3z78*+&<0C*o79*@&�3�06);).*H(+-:/ ,90CAcG;7I)+24I+-7&WB;27) & B & 2-, & 06) & &)*,3)Q

2 ]PO5&93*)42�� ,d7I)+2-0'3 09> >@(�3+O;78A &/3 ).79- ,/0CAcG.0'35&93*).3) & 7I)�79*+&J78I+3+&/3 ) 0C* 2-3+79O�&<\E(;7F)4& 273 ) & & &21 243�)42-3K5GK*+0bO+(�,/),3<Y¤763+Ok5C(�24O+763�,9& 0'3�B & 7I)�243z76,/),(;79-4-0/ ,909A?A(&<*@,92=78-4-:/g7d687624-479I+--&W*.7I) & &<*;) & 7I3eA(&<*+&)-:/7�{@G.0C3H3+2:I+-:/K�&<A(&<*H5'2-3K5�G+*+0bO+(�,G)dQ

2�� (�2:O;763�,/& 063 & 79*HOKBL79*+&[sP3+08> )PB�79*@&�),*.79O�&/09i¤3<Y9G+79*@)+2-,<(K-=79*H-:/WB;2C) & *+&<3HG.&/,/) )40M,<*H/bG5)+0C5C*,79G & 27,�2:AlsGK--&<A(&93*).7I)4270'3+3<QL{ %'& &<*+&;2:3�7F5C*+&<7I) 3�&/&<O�>N0C* & 78*,OKBL79*+&[sPI;783+&<O?79(5) & &93*)+2-,d7F)42-063l793 2-3 ¡ 0C*�)4& ��� 7KYIK(5) & 79*,ONB�79*@& 2:A?GK--&<A(&93*).7I)4270'3 09>�,<*M/NG )40C5C*,79G & 27,c79-45'09*+27) & Ac3 243IV/O3�0�A &<763+3�7jG;763;7I,9&d7NQ¡ 0C*<&[1+78A?G+-7&9Y�3+&9&�}|� � �w�S>N0C*x7I3�763;79-0/b3+243 09>�B & &/) & &<*�,)*H/bG5)40 24AcG+--&)A &/3 )+&<O 2-3 & 79*,ONB�79*@& 2:335&9,9&)3,3,79*+2:-:/aA(0C*+&<).*H(+3@)PB�0C*@) & / ) & 763kB & &93 2:A?G+-7&<A(&93*)4&)O 273k3@09> )PBL79*+&8Q �M2-3*)d� �H] )W762-3�� )�3�&9,[s&)3,3,79*+2:-:/v3@0+Q �E�

� �

Page 118: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� ����� � �"!�� ��� � !�� �'� � � �"� �`���� ����� � �

� ��� �������������� �� ��� ��������������������������� �!���� � � �"����� � �� ��#� ���$��� �� ��� ��� ��%� �&�'��� �� (� ��� �"����� �)����� � �����*�$� �� � �����������*� � ������ �� �+���-, �!��������� �.�� �� � �� � �� 2:A �M0C*+3�273+5l763+Ok£L*@2=763ayu763+O�&)-4-�Y_�r��/9�a} �r�C�w�

]A3*)4&)-4--2:5'&93*),-:/ ,90'3�,/&9206'&<Oe3H/b3@)+&<A 3@),*,(�,G).(+*@&x*+&)Ag7I2-3+3o3+&)*+270C(+3,-0/j(�3+O5&<*H6879-:(�&<O�Q %'& &x79G+G+*@0CG+*+247I)4&(+3@& 08>$3�).*,(5,/).(K*+&B�793u79-:*+&<79OK/v*@&9,/0C5'3�2 � &<Ok793o7 ,<*@&d7I)+2:6'& ).793,D 2-310k(+-C)42-,)3�{ &8Q|5+Q0Y;3+&/&?}2/43����273h�d�C��3NY763+O 2C).3XI.&/3�& ��),3 2-3B) & 7I)U3M/b3@)4&)A B�&<*+&v66&<*M/ ,90'3K3+24O5&<*.78I+--& 2-3B) & &jG+*+08,9&)3,3�09>oO5&)6'&)--0CGKA &/3 )c7I3+O3,(KI+3+&)\b(5&93*) &)660C-4( )42-063_Q�y;&65 &/,/)4273+5H0'3 ) & & ��09*+3�273+58sZyu763+O5&<-4-z\E(�06)4&h79I10r6'&8Y 27)L2:37���� � �f7�682C)�79-,<*@&d7I)+2:66& )�793HD�273 ) & & 3�&)B A(24-:--&9353�24(+A p G1&<* & 79G+3�&26'&93 A(0C*+&k3+0D) & 763 I1&)>N0C*@&9Q �M0�B�&)66&<*)Y 27)AU(+3�)�I.&"76,9,/0CAcG;763�27&<O IV/ ) & 0C*@0C(+5 & (�3+O5&<*,3�)�763KO�2-3+5�09>>) & &�O�&<3@24*@&<O *@&<\E(�2:*+&<A(&93*),3e763KO ) & &92:*24AcG+-72-,d7F)42-063+3<YS793lB&)-4-z793cO�&/).7624-7&<O &/3+5'273�&9&)*+2-3K5 )+0B&93K3,(+*@& ) & 7F) ) & & 2:A?G+-7&<A(&93*)�7F)42-063�O�0 &)3 3�0I)(�3+O5&<*,A(2-35&FB & 7I);) & &3�).*,(5,/).(K*+& & 793u7I)+)+&<AcG5)4&)OK)+0c76, & 2-&26'&8Q

%'& &;&<AcG & 783+243 273 ) & 243�*@&<G10C*@) 2:3 0'3 �#������ ����������&�����-��������������������763KO"���)���8�����&����� �#������ ��*�������&����� ) & 7F)79*@&(273+O�&)G.&/3+O�&93*)>09>�G;78*@)427,<(+-479*F3M/N3�)4&)A 7I3+OB3�&G)PB09*,D�O�&<3@245'3K3X7I3+OB273+O�&<G1&93KO�&93*)�09>�3HG.&/,92���, 2:AlsG+-7&<A(&93*)�7I)+2-0'3K3<Y�IK(5)3@)+24-4- �;*HA?-0/k*@0 0I)4&<O 273 ) & &�IK*+0V79O�3@&/)<09>S*@&<\E(�24*@&<A(&93*).3F>N09*F3,(+*M682:6879I�2:--27)P/9QJ]A3) & 243$BL7d/CYVB&o7d660'24Ol5'&G)+)4273+5FA(24*@&<O�273�) & &'O�2:3@)+2-3�,G)42-063+3T79A(0'3+5�) & & � 0'273*) % &/, & 3�27,d79- � *+, & 2C)4&/,/).(K*+& ��3��)+&9, & 3�27,d79-_79*+, & 2C)4&/,/).(K*+&<3 �+Y �@0CG1&<*,7I)4270'3;79-�79*@, & 27)+&9,G).(+*@&<3��KY�763+O �H3H/b3�)4&<Ac3o79*@, & 27)+&9,/),(+*+&)3��e{¥3@&9& � GbsG1&93+O�2¦1�$ &9,G)42-063lqWQ:�r� p 78-4-809>+B & 27, & -=76,�D�7�),*,(�&�3@&93+3@& 09>�79*@, & 27)+&9,G).(+*@&:9X793^B&)-4-+783 ) & &'t 0Vt � 0V79-$ &/,<(+*@27)P/ � *+, & 2C)4&9,G).(+*@& ��3F79IK3@).*,76,/)<Y;5'&935&<*+27,9Y+3HG.&/,92�� ,9Y�763+Oa-70C5'2-,<79-_78*+, & 2C)4&9,G).(+*@&<3z763+OL27),3'3+08s ,d79-:--&)O3+&/,<(+*@27)P/�79*@, & 27)+&9,G).(+*@&g{@3+&/& � G+G.&/3+O�2¦1 $ &9,G)4270'3kqWQ��C�[Q��$ 0CA(& 09><) & &�79*+, & 27)4&/,/),(+*.79-z3@),*,(�,G).(+*@&<3K,90'3+3@24O�&)*+&)O & &<*+& 273V6'0C-06'&�*+&)-=7I)+2:66&<-:/ (�3*).*H(+3@)+&<O &93+Obs

(+3@&<*�3H/b3�)4&<Ac3 ,90CAxI�2-3�&)O B;27) & (+-7),*.7ws¢O�&<G1&93+O+79I+--& ).*,(K3@)PB�0C*@) & / 3+&<*M6'&)*,3(0C(5)�09>oB & 27, & 3@).*H(�,/),(+*.78-79*@, & 27)+&9,/),(+*+&)3 ,<763 I1& ,9063�,9&/2:6'&)O_Yo763+O >@*+0CA B & 27, & 3,(K*H682:6879I+-7&k3M/b3@)4&)A?3g763+O 35&/)PB�0C*,DE3�,<763 I1&O�&26'&<-70CG1&<O 0C* ,90'3 �;5C(+*@&<O_Q �W>XG;79*@)+2-,)(+-=79* 2-3*)4&)*+&)3@)k79*+&�78*+, & 2C)4&9,G).(+*,79-J3@),*,(�,G).(+*@&<3L) & 7F)L2-3�,)-4(+O�&79(5) & &93*)+2-,d7F)42-063U3+&)*H6'&)*,3)Y��;-7&�3+&)*H66&<*,3)YK7I3+O�3�&/)PB�0C*HDU3+&)*H6'&)*,3)YbB & 27, & (�3+O�&)*�5'&93�&)*.79-72 � &<O�O�&)G.&/3+O�&935,9&,d7I3 0r6'&)*.79-:-_G+*@0�682:O�& & 245 & -:/v3H(+*H68206978I+--&763KO & 2:5 & -0/g3@&9,<(K*+&�3H/b3@)+&<Ac3W763KO 3�&G)PB09*,DE3<Q$ 0CA(& 09><) & &�3 & 09*@)Hs )4&)*,A ,<763+O�2:O;7I)+&�79*+, & 2C)4&/,/).(K*+&<3L,<763 &)6'&/3*).(;79-:-:/ I.&�A?79O�&�A(0C*+&e3,(+*M6 206Vs3 4�57; LKGM8<>Sn7;�#�C6 >H6���&�MN�; GMD<= 5C6 ><;�=r><[CDH;=<�6��><5C;?>A@�BDC*E�FHG8E�IKJML�N�OQP)RSOQE�BD@�TMUZ698S8H69I�ECL VV;<>H57;#8<><DH[C=r><[CDH; �MN GlVl>H576���Cv < � L >H5��A[��A5 �A[7D><;�D<I�8W; GMDH= 5C6 ><;!=r>H[CDHGMLS8<><DH[C=r><[CDH;=< GCnX;H8<><DH[C=r><[CD GML GMD<= 5C6 ><;!=!><[CD<;)< IJG!V 8H;!;!IQ>"� U0;J>HGM[7>"�AL����A69;!8 �A[7><8H69nC;�><5C;J=���l><;MY�> �MNS>H5C698:DH;!E �AD<>�b

><5C;rV GMD<;:6�W><; 7nC;!np>���;!I�EC5CGM8H6[Z!; >H57;:n7;�8<69DH;!nRNP[�CnCGMI�; W>HGML D��AL9; �MNO8<><DH[7=!><[CD<;WbFG7np>���G�q �A69n =���7NP[C8H6���pDH;!8H[CL ><6��� NPD��AI ><5C; IJGM8H8H6 qW;!L VI�698HE7LKGM=�;!n&� qW;!DHL��WGMn76��� �MN%>H57; d��ADHn\; GMDH= 5C6 ><;!=r>H[CD<;=<�>H5�G.> GMDH698<;!8�6��>H57;8]W4 � GCn_^�`#j � v

w ���

Page 119: Practical Architectures for Survivable Systems and Networks (Phase

79I+-7&gIV/"5C*.79OK(;79-&26'0C-:(5)4270'3_Q � 3K>N0C*�).(�3+7I)4&)-:/CY$3+0CA(&�09> ) & &v--063+5'&<*Zs )+&<*,A 78G+G+*+0C76, & &<3�) & 7I)>,90C(+-:O76, & 27&)66&�).*,(K-:/ & 245 & 3,(+*M682:6879I�2:--27)P/n*+&<\E(�2:*+&vA(0C*@&g*+&26'0C-:(5)4270'3;79*M/ 3�&)B O�2:*+&9,G)4270'3+3 � ) & &)/ 79*+&?AU(�, &A(0C*+&l>¥79*,3@245 & )+&<O_Y�7I3+OB,/0'3+3+&)\E(�&93*).-0/ -7&<3,3x--24DI&<-0/ )40eB;273�G10CG+(+-479*�3,(+G+G10C*�)�79A(0'3+5L) & 093+&v3M/N3�)4&)AO�&26'&<-70CG1&<*,3�B & 0X79*+&oI1&93*) 0'3c--0rB&)3@)MsPG10C3,3@24I+-7&2sA,/0C3@)�3@0C-4( )42-063+3<Q %'& &o*+&9,/&93*) 3506)Hs )40808sP3H(+*,G+*@243@2-3+5FO5243Ms,90r66&<*H/�IV/Xm � $ � ) & 7I)�) & &924* �M>¥783@)4&)*<YI, & &d79G1&<*)YCI1&/)+)+&<* �W79GKG+*+0V7I, & 243^7u*+&<3@0C(�3+O52-3+5o>¥7624-:(+*+& 2:3^7M,)--&d78*24-:-4(+3�).*,7I)4270'3�09> ) & &�*+243HDE3<Q ¡ 793@)+&<*z763+O , & &d79G1&<*W79*+&�5'&/3�&<*,79-4-0/ �+� �`I.&G)+)+&<*oB & &93n3M/b3@)4&)A?3F79*+&�A 2:3Ms3+270'3 ,)*+27)+2-,<79- QU{ ¡ 0C*M&21K79AcG+--&8Y�3+&/&lyu]�$���$VsM�9�KQ|� � & )@).G_� �C�I,<7I).-7&<3,3)Q 35,<- Q|76,8Q|(+DN�9y;243HDE3��C�9�NQ � � Q & ).Ac-T7I3+OQ|�C� & )+).G����C�F,d7I),--&<3H3<Q 3�,<-�Q 7I,9Q�(+DN�9yM2:3,DE3��9�9�KQ|�C�KQ & ),A?-^>N0C*F3@0CA &xO�243@,<(+3H3+2-063 063 ) & & 0k79*,3��`763+O5&<*<Y`7I3+O� &)66&<3+063�}¦��/ � �;>N0C*S763?763;78-:/b3+2:3 09> ) & &o*+0C-7&M08> ,)--0C3@&<ONs¢I.0d1lG+*@0CG+*@2-&/).79*H/U3+09> )PBL79*+&M2-3lA(243H3+2-063NsA,)*+27)+2-,<79-3H/b3�)4&<Ac3<Q �

%'& 2:3 , & 79G5)4&)*�,/0'3+3@24O�&)*,3AU(+-C)424-7&)66&<-0s¢3+&/,<(+*@&�3H/b3@)+&<Ac3x793JB�&<-:-f783�3@2-3+59--&2s¢--&26'&<-$3H/b3@)+&<Ac3<Q $82-3+5C-7&2s--&26'&)-L3H/b3�)4&<Ac3l79*@&v(+I�2:\b(527)409(+3<Q 0k(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+&?3H/b3@)+&<Ac3l79*+&gO�&<3@24*+&)O�IV/ ) & &jt &<G+79*@),A &/3 )>09>t &)>N&/3+3+&8Y�I+(5) 2-3*),*+0bO+(�,9&aA?763V/�G+*@0CI+--&)A?3 09>M) & &924* 0rB;3�p 3@0CA &L09>zB & 2-, & ,d7I3 2-3*)+&<*H>N&)*+&jB;27) &) & & 3�&/&<O+3c>N0C*l3,(+*M682:6879I�2:--27)P/9YfG+79*@)+2-,<(K-=79*H-:/ 2:> 3506)?79O+O+*@&<3,3@&<O~3M/N3�)4&)A 27,d79-:-:/CQ�]PO�&<79-4-0/CYLAx(+-7)+24--&26'&)-0s3+&/,<(+*@&j3H/b3@)+&<Ac3U3 & 0C(+-4O�I.& ,90'3��+5C(+*.78I+--&lB;27) & 0'3+-0/�A 273�24A?79-TO�&)G.&/3+O�&/3�,9& 0'3�AU(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+&,909A?G10'3�&/3 ),3<YE*.7F) & &)* ) & 763c*+&)\b(524*+273+5G.&)*H68793@2:6'& & 2:5 & sZ783,3,(K*.763�,/& 0���$�) & *+0C(K5 & 0C(5) &26'&<*M/(&93+ONs¢(+3+&)*,909A?G10'3�&/3 )<Q ¡ (K*@) & &<*,A(0C*@&9Y!) & &c3@2-3+59--&2s¢--&26'&<-$3H/b3@)+&<Ac3X3 & 0C(+-:O"I1&�2-3*)4&)5C*.78-4-:/k*+&)-=7I)+&<O )40L) & &cAx(+-0s)42:--&26'&<- 3M/b3@)4&)A?3)Y�*.7I) & &<*;) & 7I3 ,/0CA?GK--&/)+&<-0/vO�20i &)*+&93*)o>¥79A(24-72-&<3�09>$79*+, & 2C)4&/,/).(K*+&<3)QL]¢>T763e78*+, & 2C)4&9,G).(+*@&243oG+*@0CG1&<*,-0/ ,9063�,9&/2:6'&)O_Y¤7lAx(+-7)+24--&26'&)-_3H/b3@)+&<A 3 & 0C(+-4O 3�06) & 7d6'&<)40cI1&X3@245'3�2�� ,d7I3 ),-:/gO�2:i.&<*@&93*)o>@*+0CA27),3z3@2-3+59--&2s¢--&26'&<-�,/0C(�3*)4&)*,G;79*�).3)Q %'& 2:3 2:3W7c5'0V79- ) & 7I) & 793 3�0I)WG+*@&)682-09(+3,-0/kI1&9&/3nG+(+*H3,(�&)O_Y 763KOe*,(53+3,909(�3*)4&<*�)40>) & &FO�27,/)�7F)4&<3�09> ) & & % *H(+3@)+&<O�q0CAcG+(5)+&<* $ &9,)(+*+2C)P/vRT6879-4(+7I)4270'3jqL*@27)4&)*+247v{ % q $NRfq'�LO5243Ms,<(K3,3+&)O 273aq & 79G )4&<*��KQ ��0rB�&)6'&)*<Y 2C)�3+&/&<Ac3 & 2:5 & -:/?79ON6 2:3.79IK--& 20>W0���$g3H/b3@)+&<Ac3o79*+& &)6'&)* )40UI1&9,/0CA(&G+*,76,/)+2-,d78-4-:/U76, & 27&)6879I+-7&9Q�mM&)6'&)*@) & &<-7&<3,3)Y5) & & 2-3 & &<*@&93*)273�,909A?G+-7&/)+&93�&)3,308> 0���$?*@&<\E(�24*@&<A(&93*).3fAU(+3�)I1&X78O+O+*+&)3,3@&<O_Y 2-3aG;78*@)427,<(+-479*LB;2C) & *+&)3,G1&9,/)M)40�) & &*+&<\E(�2:*+&)A &/3 ),3u>N09* 2-3*)4&)5C*+2C)P/j763+Oa3H(+*H682:6879I524--2C)P/CQ

� ��� � ���� �� � ��� � � � � ��� ���@� ��� � ��������� ���

$ &26'&<*,79-;>@(�3+O;78A &/3 ).79-�79*@, & 27)+&9,/),(+*.78-;G+*+273�,92:G+--&)3�79*+&;&<3H3+&/3 )+2=79- )+0�&2i &/,/)4206'&z79*+, & 27)4&/,/),(+*.79-;3�).*H(�,/),(+*+&8Y&d7I, & 09>LB & 2-, & ,<763B,/0'3+3@24O�&)*.79I+-0/O24AcG+*+0r66&(0r66&<*.78-4-�3,(+*M682:6879I�2:--27)P/9QgmM06)X3,(+*HG+*+2:3+2-3K5C-:/9Y�) & &<3@&gG+*@2-3Ns,92:G+--&)3 & 7r66&�O�&9&)G�*+0806).3M2-3K) & &x3+&9,)(+*+2C)P/n7I3+On3+08> )PB�79*@&2s &93+5'273�&9&)*+273+5 ,/0CA?Ax(�3�27)+2-&)3<Qo]A3�G;79*�)42-,)(+-=78*<Y3+&/& ) & &��r��/#3�G+79G.&)* 09> $K79-7) � &)*o763+O $ , & *+08&<O5&<*X}��9��/w��Y�2-3jB & 27, & A?763V/�09>�) & &>N09-4--0rB;273+5>2C)4&<Ac3o79*@&>N0C(�3KO_Q

2 � � � -�� #" -�� ( � � ]A3L,909A?G+( )4&<*L3H/b3@)+&<A G+79*,-4763�,9&8Y+79IK3@).*,76,/)+2-0'3 2:3�) & &79I�2:--27)P/�)+0UO�&)3+,<*@24I1&J--0C5620s,<79-�>@(�35,/)4270'3;79-727)P/(2-3 2C).3 0rB;3 )4&)*,Ac3'*.7I) & &<* ) & 763L2-3V6'09D8273+5 24AcG+--&)A &/3*)�7I)+2-0'3Ns¢3,G1&9,/2�� ,uO�&/).7624-:3<Y7I3+O�)40�Ag793HDx3H(�, & O�&G)�762:-43T>@*@0CAE) & &;2-3V6'0CDI&<*H3�09>.) & &o5'206'&/3l>@(53�,/)+2-0'3;78--27)P/9Q � I+3@),*.76,G)4270'3 & 24O�&)32:A?GK--&<A(&93*).7I)4270'3nO�&G)�762:-43J>@*+0CA ) & &cG+(+*H6827&)B 09>�) & &(2-3*)4&)*H>¥76,/&9Q � I+3@),*.76,G)42-063B243G;78*@)427,<(+-479*,-0/(K3+&)>@(K- 273 & 24O�273+5L0C**+&<OK(�,9273+5n79GKG;79*+&/3*)>,/0CA?GK--&21 2C)P/ 09>'7�3H/b3@)+&<A 0C*�3,(+IK3H/b3@)+&<A�Q���35& 2:AlsG10C*�)�763*)SAg7I3�2:>N&)3@)�7F)42-063(08>`79I+3�).*.7I,/)4270'3(243�>N0C(�3+O 2-3 2:A?GK--&<A(&93*).7I)4270'3NsA273+O�&)G.&/3+O�&93*) 273*)4&<*M>¥76,9&)3) & 7I)�,d763?5C*+&<7I).-0/ &93 & 763�,9& ,90CAcG;7I)+24I+-7&M273*)4&<*@0CG1&<*.78I�24-727)P/CY9*+&<(K3.79I�2:--2C)P/CYb763+Ov-70'3+58s )4&)*,A�3M/N3�)4&)A&26'0C-:(5)4270'3_Q � I+3�).*.7I,/)4270'3 243L79-43@0X>@(�3KO;79A(&93*)�79-1)40U3@24AcG+--20>�/82-3+5J>N0C*HAg79-�763+79-:/b3+&)3 09>`3M/N3�)4&)A?3 273) & &o-=79*H5'&9Y*&/3;79I+-72-3+5J*@&d793@0'3�273+5�79I.09(5)f79I+3@),*.76,G) &93*)42C)42-&)3�*.7I) & &<* ) & 763 ) & &/24* 24AcG+--&)A &/3*)�7I)+2-0'3+3)Q

2�� ��1�� � "F � " #���! �� 1���� � �J� ]A3 A 0C3�) ,<793+&)3<Y'3@&<G;79*,7I)4&k-=7d/'&)*,3 09>79I+3�).*,76,/)+2-0'3H,d763 79OK68763*)�7�s56&90C(+3H-:/?I.&�2:O�&93*)+2�� &)Oa763+OaO�243�)4273+5C(�2:3 & &)Og>@*+0CA 0'3�&J7I3�06) & &<* 2-3�)+&<*HA?3 08>�) & &F>@(�3�,G)4270'3+3�G1&<*Zs

w �%w

Page 120: Practical Architectures for Survivable Systems and Networks (Phase

>N09*,A(&<Oa763+O ) & &<2-3K>N0C*HAg7F)42-063 &93*)+27)427&<3 273V6'0C-06'&<O�QfR�76, & 79I+3�).*,76,/)+&<O�-=7d/'&)*'3 & 0C(K-4OaAg783,DvA(0C3@)08> ) & &�2:O�2-093H/83�,<*,793+27&<3;09>$--0rB&)*o-=7d/'&)*,3<Q %'& &>@(�3�,/)+2-0'3+79--2C)P/v7I)z763V/a-47r/6&<*u3 & 09(+-4O�I.&3HG.&/,92���&<O273()+&<*HA?3�09>!) & & &93*)+27)427&<3f7I) ) & 7I)f-=7d/6&<*<Y 3�06)�2-3()4&<*HA?3 09> -70rB&)*MsP-47d/'&<*�>@(�3�,G)4270'3;79-727)P/CQ � 3@24AcG+--&&[1K79A?GK--&�243'562:6'&/3kIV/�) & &-=7d/'&)*+273+5 09> % 79I+-7&��KQ:�9Y;79-7) & 0C(+5 & 273�7lO5&/)�7I24--&)O�79*+, & 2C)4&/,/).(K*+&9Y &<76, &08> ) & 0C3@&c-47d/'&<*H3JA 2:5 & ) 2C).3+&)-:>SI1&�3,(+I+3�).*H(�,/),(+*+&)O_Q?�J(K*�3�06)4270'3 09> ,909A?G+*@0CA(243+&�>@*+0CA 0C(5),3+24O5&273�,<-:(+O�&)3�,/0CA?GK*+0CA(243@&<3 0C*+2:5'2-3;7F)42-3K5F>@*+0CA & 27&<*,79*+, & 27,d79-¤79I+3�).*,76,/)+2-0'3+3f7I) & 245 & &<*f-=7d/'&)*,3�783fB�&<-4-783F>@*+0CA 0I) & &)*X78I+3@),*.76,G)42-063+37I)�) & &c3,79A(&c-47d/'&<*)Q ¡ 09* ) & &)3+&cG+(+*HG.0C3@&<3)Y�B�&c*@&)>N&)*<)+0 �#������ (� ����������)�������� (� ��7I3+O ���$�� ��$� � ����� ���������������� (� ����*@&<3HG.&/,/)4206'&)-:/CQ q09A?G+*@0CA(243+&)3>09> & 0C*+2 � 0'3*)�78-�79INs3�).*,76,/)+2-0'3L,d7I3�I1&<,90'3K3+24O5&<*+&)On793 ,/0CAcG+*+0CA(243@&<3�>@*@0CA�B;2C) & 273L)+245 & ),-:/ ,90C(+GK--&<Oa3M/N3�)4&)A?3)Y.0C*o783,/0CAcG+*+0CA(243@&<3L>@*@0CA 09(5).3@24O�&JB & &/3�&)66&<* 273*)4&<*@3;79-`79( ) & 0C*@2 � 7I)4270'3�243 )+0lI.&<2-3V660CD6&)O_Q

2 � � " �� ������ - � ( � � � I+3@),*.76,G)42-063�A?793HDb3 2:A?G+-7&<A(&93*)�7F)42-063�O�&G)�762:-�7I)c7�G;79*�)427,<(+-479*�2-3*)+&<*H>¥7I,9&9QR 3�,<79G+3H(+-=7I)+2-0'3L09>�) & &>@(53�,/)+2-0'3;78--27)P/ 09>�) & 7F)u79I+3@),*.76,G)4270'3 & 793 )PB0g79O+O�2C)4270'3;79-�7I)+),*+24IK(5)4&)3<� 27)& 2-3+O�&)*,3<) & &cO�&)*+2:687I)+2-0'3O09>2-3*)4&)*+3;78-S3�)�7I)+& 273K>N0C*HAg7I)+2-0'3n>@*@0CA 0CIK3+&<*M687I)4270'3 08> ) & &(2-3*)+&<*H>¥7I,9&9Y7I3+O 27)U7I)+)+&<AcG5).3 )40�G+*@&)6'&/3*) ,/0CAcG+*+0CA(243@&?>@*@0CA 0C(5).3@24O�&lp >N0C*>&[1K79A?GK--&9Y�IV/B2-3*)4&)*H>N&<*@&93�,/&B;2C) & ) & &�2-3*)4&)*+3;79-�0CG1&<*,7I)4270'3+3<Qu] ) 2:3z*@&<-7&)68763*) )+0gI106) & O5&<3+2:5'3�{N&93+3H(+*+273+5 ) & 7I)�) & &�273 )+&<*@3;79-4378*+&g-70C5'27,d79-:-:/ & 2:O+O�&/3��X763KO 24AcG+--&)A &/3 ).7I)4270'3 { &93K3,(+*@2-3+5 ) & 7I)>) & &�273 )+&<*@3;79-43x79*+&gAg793HD6&)O"p3H(+Ib§@&/,/)M)40 2-3K>N&)*+&/3�,9&)3M) & 7I);,d7I3kI1&O+*.7dB;3_Y�793o3H(+5C5'&)3@)4&)OeIV/h}��C�N�<��Q

2 �� 1 ( ��� 1 " - &7( ����1��'- 1 ���� � � � � � %'& &<0CIb§@&9,G)Hs 0C*+27&93*)4&)O�G+79*.79O5245CA�3�06)+&<OL2-3 $ &/,/)4270'3 3NQQ/&/3�,909A?G;783,3+&)3�) & &g78I.0r6'& ,90'35,9&<G ).3>08>o79I+3�).*.7I,/)4270'3_Y�&93�,<79G+3H(+-=7I)+2-0'3�Y�273 & &)*+27).763�,/&9Y�763+O�G10C-0/EsA(0C*HG & 243HAkYwB & 2-, & ,/0C-4-7&9,/)+2:66&<-:/�G+*@0r6 2:O�&o7FG106)4&/3 )+2=79-:-:/J6879-:(;79I+-7&L3@),*,(�,G).(+*@2-3+5<0C*H5V763�2 � 273+5WG+*@2-3Ns,/24G+-7&9Qo{ ��0rB�&)6'&)*<Y127)oAU(K3@)oI1&�GK*+0CG1&<*H-:/�2:A?GK--&<A(&93*)+&<O 2-3L0C*HO�&<* )+0cI1&<&)i.&9,G)42:66&9Q �

2� 1 � � � � � � 1 � � �r- � � t &<G1&93KO�&93�,/&kGK*+24A?79*@24-:/ 0'3H0'3�&a3M/N3�)4&)A GK*+0r6824O�&)*<Y063�&a3+09> )PBL79*+&�O�&[s66&<-70CG.&)*<Y10'3�& & 79*,ONB�79*@&xG+*@0NOK(�,9&)*<Y10'3�&x3@&/) 09>�G+*@06)408,90C-:3<Y 0'3�&X3+&G) 09> 35&/)PB�0C*,Dk3+09> )PBL79*+&8Y 0'35&35&/)PB�0C*,D ,/0'3�3�&/,/)4270'3_Y 0'3�& � &<I�I+*+0rBo3+&)*<Y 09*�0'3�&L0CG1&<*.7F)42-3K5�3H/b3@)+&<A 243�273 & &<*@&93*).-0/�(�3VB;243@&20>�3,(+*M682:6879I�2:--27)P/K2:3J7j3+&<*@2-0C(K3J5'0V79-�Qxq09A?A(0'3n>¥79(+-C)FA(0NO5&<3J763KO ,/0CAcA 0'3�3@&9,)(+*+2C)P/e6b(+--35&<*.7�sI524--2C)427&<3 ,<763k*@&93+O5&<*�) & & &93*)42:*+& 2-3K>N0C*HAg7F)42-063�2-3K>@*,793@),(�,/),(+*+&�(+3@&<--&)3,3u>N0C*oG+*+0C-70'3+5'&)OkG1&<*@2-0bO+3;09>)+24A(&9Q � -7) & 0C(+5 & O�2:66&<*,3@27)P/ 2:3�O�&)3+24*,79I+-7& 2-3 &26'&<*M/ 0'3�&�08>�) & &<3@&O�24A(&93+3@2-0'3K3<YKO52:6'&)*,3@27)P/ & 793 27),30rB;3?3+&/)09> *@243,DE3Tp 273�,<-:(+O�273+55C*+&<7I)4&)*�,/0CA?GK--&21 2C)P/�2-3g76, & 2-&2682-3+5 2-3*)4&)*+0CG1&<*,79I�2:--27)P/9YVAg7I2-3*)�76273Ns78I�24-727)P/CY ,9080C*,O�273;7I)+2-0'3h763+Oh3H/83�, & *+0'3�2 � 7I)+2-0'3�79A(0'3+5aO�2:66&<*H3+&(,90CAcG.063�&93*).3)Q %'& (+3<Y�O�2:66&<*H3+27)P/2:3 2-3j5'&/3�&<*,79- 3�06)M3�&/,9&)3,3.78*+24-0/jI1&93�& � ,92479- Q

2 � ( �t( � �� � � �r- � � %'& &oG+*+273�,92:G+--&) & 7I)�A(0NOK(+--&)3<YC3H(+I+3H/b3�)4&<Ac3<YK763+Ol3H/b3�)4&<Ac3S3 & 0C(K-4OlI.&'*@&d79Obs2:-:/>,90CAcG.093.79I+-7&�B;27) & 0C(5)f79O+O527)4270'3;79-5&)i.0C*@)�243�>@(�3+O+79A &/3*)�79-�)+0�) & &zO�&)Ag7I3+O+3 09>_3H(+*H682:6879I524--2C)P/p 79-C) & 0C(K5 & ) & &>24AcG+-72-,d7F)42-063 243 3506) &/3 )+24*@&<-:/K0CIV682-09(+3 2-3e7?B�0C*,-:O 2-3eB & 2-, & A(0C3@)�,90CAcA(&<*Ms,/2=79-u3+08> )PB�79*@&O243�3�0I) &d793@24-0/ ,/0CA?G10C3,79I+--&8Q %'& &�O�&9,/0C(+G+-72-3+5D08>>,/0'3�,9&)G5).3)Y 273 )+&<*M>¥76,9&)3<YF7I3+O2:A?GK--&<A(&93*).7I)4270'3+3�) & 7I) 243<3�&/,9&)3,3.78*H/O)40K&93 & 763�,9& ,90CAcG10C3.79I524--2C)P/K,d763 ,90'3*).*@24I+( )4& 2-3+O524*+&/,/),-:/)+03,(+*M6 206879I�24-727)P/>2-3�6879*+270C(+3�B�7d/b3�p >N0C* &[1K79A?GK--&9YEIV/ 2-35,<*+&<793+273+5 ,90CAcG.063�&93*) 2-3+O5&<G1&93+O�&/3�,9&8Y273*)4&<*@0CG1&<*.78I�24-727)P/CY 5�&21 24I�2:--2C)P/CY 5'&/3�&<*,79--2C)P/CY�763+OhG.0C-0/bA 0C*HG & 27,�(+3.79I524--2C)P/CQ %'& &?*@&<\E(�2:*+&<A(&93*)�09>>¥7I,924-7&�,90CAcG10C3.79I524--2C)P/ 09i.&<*H3x7�3@),*+0'3+5�>N0C*+,/2-3+5a>@(�3�,G)4270'3B0'3�79*+, & 27)4&/,/),(+*+&)3U763+O"3H/b3@)+&<A ,90'3bs�+5C(+*.78I�24-727)P/CY�793,3H(+A 273+5B) & 7I)�2C)�2:3�2-3*)4&/3+O�&)O )40�I1&n*+&/,90C5'352 � &)O 763+O & 063�0C*+&)O ) & *@0C(+5 & 0C(5)dQq09A?G10C3.78I�24-727)P/�,<763�I1&>,9063+3+2:O�&<*,79I+-:/K&/3 & 763�,/&<O�IV/K) & &U(K3+&�09> & 0C*+2 � 0'3*)�78-�7I3+Oe6'&)*@)+2-,d78-T79INs3�).*,76,/)+2-0'3_Y5&93�,<79G+3,(K-=7I)+2-0'3_Y+763+Oa3+&)G;79*.7F)42-063K08>$G10C--27,)/v763+OaA &/, & 763�2:3,A�Q

w ��

Page 121: Practical Architectures for Survivable Systems and Networks (Phase

2� 1 � � � ��� ( � � 1�� � � 1 � - 1��'- � " - � ( � � � "S" 1 � � " ( �'-�� (:�W� � -7) & 0C(+5 & A?763V/�O�&<3@245'3bs&)*,3�A?7d/B,/0'3+3+2:O�&<*l78(5) & &/3*)42-,<7I)4270'3�793l7I3�78> )4&)*@) & 0C(+5 & )dYS763KO�76,9,/&<3,3 ,/0'3*).*+09-�*+&)--&)68763*)�063+-:/>N09* ,9&)*@)�7I2-3�76,/,9&<3H3 )P/bG1&<3)Y^3@&9,)(+*+2C)P/�*+&)\b(524*+&)37�) & 0C*@0C(+5 & G1&<*H3,G1&9,G)42:66& 09>SG.&)*H68793+206'&c79(5) & &93bs)+2-,<7I)4270'3�763+O 7I,9,9&)3,3�,/0'3*).*@0C-43 ) & *@0C(+5 & 0C(5)?3H/b3@)+&<A 7I3+O 3�&G)PB09*,D 79*+, & 2C)4&/,/).(K*+&<3)Q � 3�2:>N09*,A),*+&<7I).A(&93*)�09>`3+&/&<A(2-3+5C-0/lO�2:66&<*H3+&J76,/,9&)3,3'A(&9, & 7635243,Ac3,<763vI1&F76, & 2-&)66&<OjIV/?*+&9,/0C5'3�2 � 273+5>,/0CAlsA(0'3a79IK3@).*,76,/)+2-0'3K3z78A 0'3K5�O�2:i.&<*@&93*)uA &/, & 763�2:3,Ac3<Q

2� 1 � � � ��� ( � �� � � � � - � - � 1 � � ( � 1 � -�� ( � #�t" ( �'-�� (:� �! �� � � �!- � � � 5'&/3�&<*,79-4-0/ 245'350C*+&)OGK*+2-35,924GK--& 2:3 ) & 7F) 09> &93+3H(+*+273+5�) & 7I) ) & &JO�&)3+24563K08>$3M/N3�)4&)A?3u763+O ) & &92:* 0CG.&)*.7I)+2-0'3+79-.273*)4&<*M>¥76,9&)32:3'3,(��(,/2-&93*),-:/a7dBL79*+&<09>�) & &<3�&/&<O+3�09>$79O+A(2-3�2:3@).*,7I)4270'3v7I3+O 09G.&)*.7I)+2-0'3_Q

2� 1 � � � ��� ( � � 1�� � � 1 "S" ( � �'- � � � �r- � � � �O1 " (� 1�� � � $824A(24-=78*�)+079(5) & &93*)427,d7I)+2-0'3l7I3+O7I,9,9&)3,3 ,/0'3*).*+09- YV76,/,90C(53 ).79I�2:--27)P/*@&<\E(�2:*+&<3�7zG.&)*H68793+206'&o79GKG+*+0V7I, & )40FA(0'3�2C)40C*@2-3+5M09>�79-:-N*@&<--&268763*)7I,/)4206827)427&<3J7F)O�2:i.&<*@&93*)�-=7d/'&)*,3<09>'78I+3@),*.76,G)42-063_Y *+&<79-0s )424A(&U7I3;79-:/b3@243�09>f3+2C).(;7I)+2-0'3K3 ) & 7I)A(245 & )-7&d79OO)40�G106)4&/3 )+2=79- ,)*+2:3+&<3)Y�763+O ) & &?79I�2:--2C)P/ )40�*+&/,90r6'&)*U3H/b3�)4&<A 3�)�7I)+& 2-3N>N0C*,A?7I)4270'3�763KO�O;7I).7B & &93 3�&9,/&<3,3,79*H/9Q %'& &)3+&(,d79G+79I�24-727)+2-&<3z3 & 09(+-4O�I1&?78O+O+*+&)3,3@&<OB273�3H/b3@)+&<A 79*+, & 27)4&/,/),(+*+&l*.7F) & &)*) & 763�79O+O5&<OK0'3e7w> )4&<*MB�78*,O+3)Q

2 + 1 �R � - � ( � ( � �t(:� � " � � � 1 "I J � � � � � 0C-72-,2/?O5& � 3�&)3uB & 7I);243�3H(+G+G10C3+&)OK)+0�I.&WO�0'3�&8Y7I3+O�A &/, & 763�2:3,A &<3�)�79I+-7243 & &<3 & 0�BE27)�243�)40vI1&�O�0'3�&8Q�$ &<G;78*.7I)+2-3+5 ) & &<A O�2:3@)4273�,/),-:/a>@*+09A 0'35&7I3�06) & &<*$59*+&d7F).-:/ &/3 & 763�,/&<3�3H/b3�)4&<A�5 &21 24I524--2C)P/�763+O�&26'0C-06879I�24-727)P/9YI&)3,G1&9,92479-4-0/ 2:> ) & &�G.09--2-,/2-&)3 ,<763I1&;, & 763+56&<OgB;2C) & 0C( ) & 7r68273+5 )+0U79-C)4&)* ) & &uA &/, & 763�2:3,Ac3<Q � 3+2:A?GK--& &21K79AcG+-7&M2:3 ) & &uO�2:i.&<*@&93�,/&I1&/)PB�&9&/3�76,/,9&<3H3Ms ,90'3*).*@0C-^G.0C-72-,/2-&<3o7I3+OK) & &�A &/, & 763�2:3,Ac3;) & 7I)z79*@&�273 )+&93+O5&<O )+0 &/3K>N0C*@,9&<) & 0C3@&G10C-72-,927&<3)Q

2 � � � � � � 1��'- ( � � 1 � - � ��� � � 1 � 1 � � & &/3�&)66&<*uO�0CA?762-3g3+&<G+79*.7I)+2-0'3�763KOjO�2:i.&<*@&93*)42479-_76,/,9&)3,3,/0'3*).*@0C-43<,d7I3�I1& &93N>N0C*+,/&<O�IV/"7k3M/b3@)4&)AkY�G.&)*,A(243H3+2-063+33 & 0C(K-4O�I1&c5C*.763*)+&<OD0'3K-:/�793 3�&/&<O�&)O_Q� *.7I3 )+2-3+5 09>$3,(+G1&<*H(+3+&)*WG1&<*HA 2:3,3+270'3+3 2:3z7�5�7959*.763*)u6 270C-=7F)42-063�09>�) & &�G+*+273�,92:G+--&�09>$--&<793@)uG+*@2:6820s-7&<5'&8Q

2 + 1 �R � - � ( � ( � " ( � " 1�� � � � � & ,90'3+3@24O�&)* ���������?7F)j763V/ -47d/'&<* 09>�79I+3�).*,76,/)+2-0'3~783�&92C) & &)*G1&909G+--&�0C*G+*@0 ,/&<3H3+&<3 ) & 7F)�273�27)+2=7I)+&�76,G)42-063+3�2-3O,909A?G+( )4&<*H3x7F) ) & 7I)�-=7d/6&<*<09>L79I+3@),*.76,G)4270'3_Q �562:6'&/3 (+3@&<*vA?7d/ & 7d66&nO�2:i.&<*@&93*)a793H3+08,9247I)4&)O O+(5)+2-&<3 ) & 7I)v79*+& )40 I1&eG1&<*M>N0C*,A(&<O_Yu763KO Ag7d/).79D6& 0'3�O�2:i.&<*@&93*)u*+0C-7&<3'>N0C*;,9&)*@).762-3�3+&G).3 08>$O+( )42-&)3<QF{ %'& & 3�06)+2-0'3K09> �M(+3+&)*��cAg7d/jO�20i &)*'>@*+0CA-47d/'&<* )+0?-47r/6&<*)Q ¡ 0C* &21K79AcG+--&8Y ,90CAcG�2:--&<OL0C*u793H3+&)AUI+--&)O ,/0NO�& ,d7I3eI1& ,/0'3+3@24O�&)*+&<On793 ) & &�(+3+&)*08> & 79*HOKB�78*+&9Q � G+G+-72-,d7F)42-063"G+*@0C5C*,79A?3x79*+& 09> )4&/3 (+3@&<*,3�08>;0CG.&)*.7I)+2-3+5k3H/b3@)+&<Ac3<Q���&90CG+-7&j79*@&)P/bG�27,d79-:-:/u(+3@&<*,3�09>b5C*,79G & 27,d79-8(+3+&)*�273*)4&<*M>¥76,9&)3^763+O<,90CAcA?763+O )4080C-:3<Q���0rB�&)66&<*<YI) & & & (+A?763(+3+&)*2:3 09> )4&/3 ,/0'3+3@24O�&)*+&<OL)40cI1&<) & &(+3+&)*;09>$6879*@2-0C(+3 273*)4&<*@3;79-!273*)4&<*M>¥76,9&)3<Q � ¡ (�3�,G)4270'3;79-!09G.&)*.7I)+2-0'3+3A?7d/ )�78D6&cG+-=76,/& 2-3hO�2:i.&<*@&93*)xGK*+06)+&9,/)+2-0'3hO�0CA?76273+3<Q $ &<G+79*.7I)+2-0'3O09>,<*@27)427,d79-�0CG.&)*.7I)+2-0'3K3X7I3+O,/0CAcAU(�3�27,d7I)+2-0'3�>@*+09A 3�09*,A?79- 0CG.&)*.7I)+2-0'3 243L79-43@0x*+&)--&2697I3 )<YK(+3@2-3+5>0C(5)Hs 09>=sPI+763+Og3@245'3+79--273+5x7I3+O,/0'3*).*@0C- Q $8&<G;79*,7I)4270'3L09> ,90'3�,/&<*@3+3M).79D6&)3�063e7I)o-7&d793�) ) & *@&9&<,909*,*+&)3,G10'3+O�273+5l>N0C*,Ac3<�� $ &)G;79*.7F)42-063 09>�*+0C-7&<3S*+&9,/0C5'3�2 � &)3�) & & &21 2:3@)4&/3�,9& 09>_O�20i &)*+&/3 )L*+0C-7&<3W{ &8Q|5+Q0YN793L7 ,9&)*@)�7I2-3gD 273+O09>�78O+A 273�243�).*,7I)40C*0C*u763 0C*HO�2-3+79*H/j(K3+&<*.�u(�3KO�&<*oB & 2-, & 763V/�G;79*@)+2-,)(+-=79*���������{N) & 7I)M243)Y�7632-3KO�2:6824OK(;79- Y80C*o7lG+*+08,9&)3,3)Y109*o7 % q $NRfq ��� ��� �����4�LAg7d/�09G.&)*.7I)+&9Q

w ��

Page 122: Practical Architectures for Survivable Systems and Networks (Phase

� $ &)G;79*.7F)42-063 09>^O+(5)427&<3'*@&9,9095'3�2 � &<3 ) & 7I)oO�20i &)*+&93*) 273+O�206 2:O+(;79-:3L3 & 0C(+-:O 0CG.&)*.7I)+&J(�3+O�&)*'O�2:>=s>N&<*@&93*)F*@0C--&)3W7I,9,909*,O�273+5()+0 ) & &XOK(5)427&<3WI1&9273+5cG.&)*H>N0C*HA &)O_Y�763+Oe3 & 0C(+-:OeI1&x78-4--08,d7F)4&<OaG1&<*ZsA(243,3@2-0'3K3l76,9,/0C*,O�273+5C-0/CQ�$ &<G+79*.7I)+2-0'3H09>z*+0C-7&<3 243 3�&/,9&)3,3.78*H/�>N0C*�) & &L2:A?G+-7&<A(&93*)�7F)42-063D09>3+&)G;79*,7I)4270'3 09>�OK(5)427&<3$p ) & 7F) 243<Y') & &u79-4-70 ,<7I)4270'3>08>�O�20i &)*+&/3 )S7I,9,9&)3,3fG.&)*,A(243,3@2-0'3K3�76,9,/0C*,Obs2-3K5 )+0�) & &3,G1&9,/2�� ,*@0C--&JI1&9273+5lG+-=7d/'&)O_Q

� $ &)G;79*.7F)42-063H08>zO50CAg7I2-3+3�*@&9,9095'3�2 � &<3�) & 7I)cO�2:i.&<*@&93*)lG+*@0C5C*.78A?3�09*�3,(+I+3M/b3@)4&)A?3 3�&9&)OH)+00CG1&<*,7I)4&K2-3�O�2:i.&<*@&93*) &21 &9,)(5)4270'3 O�09Ag76273+3<YL763+OH) & 7I)c3@&<G;79*,7I)4&kO�0CA?762-3K3�AU(+3@) 3�06)?I1&,909A?A(2-3+59--&<OH2-3 ) & &92:*gO�&)3+2:5'3 ,90'35,9&<G ).3 0C*�273 ) & &924* 24AcG+--&)A &/3*)�7I)+2-0'3_Q $ &)G;79*.7F)42-063 09>O�0CA?76273+3 243o79-:3+0�3�&/,9&)3,3.78*H/a>N0C* ) & & 2:A?GK--&<A(&93*).7I)4270'3�09>�3+&)G;79*.7F)42-063K08>$O+( )42-&)3<Q

%'& &JG+*+273�,92:G+--&)309>`3@&<G;79*,7I)4270'3 09>`*@0C--&)3'763+Oj3@&<G;79*,7I)4270'3 09>`O+( )42-&)3o79*+&F793,3@0 ,/2=7I)+&<OvB;27) & (+3@&<*,3)YB & &<*+&<793U3@&<G;79*,7I)4270'3D09>oO50CAg7I2-3+3*+&)-=7I)+&<3>)+0 &[15&/,<(5).79I+-7&jG+*+0C59*.79Ac3<Q %'& &vA(0'3�0C-727) & 2-, � 3�2013H(+G1&<*,(K3+&<*LA &/, & 763�2:3,A 243f763�&[1+78A?G+-7&�08>!) & &�2-3;78I�24-727)P/>)+0UO�2:3@)4273+5C(�2:3 & 79A(0'3+5�O�2:i.&<*@&93*)�*@0C--&)37I3+O?O52:i.&<*+&/3*)fOK(5)427&<3<YbI1&9,d78(+3+&;) & &)*+&M243 0'3+-0/�0'3�&o3H(+G.&)*,(+3@&<*fO�0CA?762-3_QL{ $8&)6'&)*.79-�3H/b3�)4&<Ac3 & 7r66&*@&9,/&93*).-0/�G;79*@)+27)+2-0'3�&)O ) & &cA 063�0C--2C) & 27,U3,(KG.&)*,(+3@&<*x*@0C--&c76,/,90C*HO�2-3K5K)+0eO�2:3@)4273�,/)�*@0C--&)3<Y^3,(�, & 783% *,(K3@)4&)O � &935201¤Q�� ¡ 0C*@),*.763���3F3 & 79*+&)O ,/0CAcA 0'3k3@)+0C*.7956&�243J763506) & &)* &21K79AcG+-7&�09> ) & &�273;79I�2:--2C)P/)+0a79O�&)\b(+7I)4&)-:/�3@&<G;79*,7I)4&lO�09Ag76273+3<Q>$b/b3@)+&<A 79*@, & 27)+&9,G).(+*@&<3�79*+&�35&9&<O5&<O ) & 7I)<,<763O&)i.&9,/)+2:66&<-:/&/3K>N0C*@,9&U*@245'0C*@0C(+3u3+&)G;79*.7F)42-063n79A(0'3+5?O�2:i.&<*@&93*)JG+*@06)4&/,/)4270'3eO50CAg7I2-3+3)Y�76,/,90C*HO�2-3K5 )40vO52:i.&<*+&/3*)*@0C--&)3<Q�{ %'& &nO�& ��3�27)+2-0'3 763+O ,/0CAcG.0C3,79I�2:--27)P/D09>J3+&)G;79*,7I)4270'3NsA08>=sPO+(5)P/�G10C-72-,927&<3 243(,9063+3+2:O�&<*@&<O273h}¦�9�C�<��Q��

2 � 1 � - " ( ( � 1 "I J � � � � %'& &eGK*+2-35,924GK--&L09>J-7&d793�) ,/0CA?A(0'3�A &/, & 763�2:3,A )�78D6&<3 0'33@&)66&<*.78- Ag76352:>N&<3�)�7I)+2-0'3K3<Y5&<76, & 09>�B & 2-, & *+&�5 &9,G).3M0'3L3�06);0r6'&)*,--0C79O�2-3K5cA(&9, & 763�243HA?3fB;27) & >@(�3bsO+79A &/3*)�79-:-:/ O52:i.&<*+&/3*)?>@(�35,/)4270'3;79-727)P/9Q ¡ 0C* &21K79AcG+--&8Y2:>z/'0C( *+&d78-4-:/ I.&)--2-&26'&K2-3 79-4-¦sPG10rB&)*H>@(+-A(&9, & 763�243HA?3o3H(�, & 793;) & & � 3�201�3H(+G1&<*,(K3+&<*U{@B & 27, & 2:3;2-3 & &)*+&/3 ),-:/jO+763+5'&)*+0C(+3.�2Y ) & 2:3'G+*+273�,92:G+--&B�0C(+-:O"3H(+5C5'&)3@) ) & &c(+3@& 09>�7K,/0C-4-7&9,/)+2-0'3O09>LO�2:i.&<*@&93*)�3,(+IbsP3,(KG.&)*,(+3@&<*UG+*@2:6824-7&<5'&)3J*.7I) & &<*<) & 7637U3@2-3+59--&F3H(+G.&)*,(+3@&<*uG+*+206824--&)5'&9YEB;27) & O�2:i.&<*@&93*)oG+*+206824--&)5'&<3f*+&)\b(524*+&)O�>N09*�O�2:i.&<*@&93*)oA(&9, & 7635243,Ac3<Q] )X79-:3+0a3,(K5C5'&<3�).3<) & 7F)X3�).*@0'3+5L)P/NG52-3+5K243G+*@&)>N&<*,79I+-7& )+0kG1&<*HA 2C)+)+2-3+5�0r66&<*,-70V79O�273+5K09>L(53 )P/bG1&<O09G.&)*.7I)+2-0'3+3<0'3"O�2:i.&<*@&93*) )P/NG1&<3)Qk] )�>@(+*�) & &)*X3H(+5C5'&)3@).3�) & 7I)X(�3+*@&<-47I)4&)O">@(�3�,G)4270'3+3�I.&().*+&<7I)4&)O3@&<G;78*.7I)+&<-:/9Q � -7) & 0C(+5 & ) & 2:3xA(245 & )�3+&/&<A )40e*H(�3D,/0C(�3*)4&)*>)40 ) & & 3506)4270'3B09>�G.0C-0/bA 0C*HG & 2:3,A273 ) & &�0CIb§@&/,/)MsA0C*@2-&93*)+&<O�G;79*,79O�2:5CA {@B & 27, & 24AcG+--27&<3oAU(+-C)42:>@(53�,/)+2-0'3K,d79G+79I�24-727)+2-&<3.�2Y�763V/ &)i.0C*@),3)+0rB�79*HO�G.09-:/bA 09*,G & 2:3,A 3 & 0C(+-:OnAg7I2-3*)�76273e3�).*+063+5C-:/L)P/bG1&<O�(+3.785'&9Q � 3�06) & &<*W682-09-=7I)+2-0'3k79*+2:3+&)3273jG+*+095C*.79AcA(2-3+5U-4763+5C(+795'&<3�B;2C) & 763�(�3+3@&<5CA(&93*)4&)Oe5C-70CI;79-.,90CAcA(0'3j3@)+0C*.7956&>¥7I,924-727)P/9Q

2 � * �p� � " �!-��%1 � �%1 � 1��'- -�� ( � ( � � � � - 1 � � �J1S-0/ ( � $ � - -e1 � � ( � ��� � � �� � � �r- � - &- � � � � - 1 �i� ]A3"A(0C3@)<,/0'3V6'&/3 )+2-0'3+79-�3H/b3@)+&<Ac3<Y�) & &c3@).7I)4& 09> ) & &l3M/N3�)4&)A?3)Y$AU(�, & --&)3,33H/b3�)4&<Ac308>�3H/b3@)+&<Ac3<Y�243W66&<*M/�O�2 �(,)(+-7)�)40a793@,9&<*�)�76273nB;27) & *+&<3HG.&/,/)<)40j3@&9,)(+*+2C)P/ 0C*F*@&<-72=79I�2:--2C)P/CQ�$E/N3�)4&)AO5&<3+2:5'3a3 & 09(+-4Ok7I)+)+&<AcG5) )40lA?79D6& ) & &<3@&X3�)�7I)+&<3M&21NG+-72-,92C) 0C* &)-43+&<&<793+2:-:/vO5&<*+206879I+--&8Q

2 �:( � �� � " 1 ( � � -���� " - � 1 � 1�� � 1�� " 1 ( � � �'-�� � � -0/ ( � - � 1��'- �r- �!1 � � %'& &<3�06)+2-0'3L09>�5'&93bs&)*.79-72 � &<OjO�&)G.&/3+O�&935,9&>&[1NG+--27,927),-:/?*+&/,90C5'352 � &)3 ) & &*+2:3,DE3;2-3 & &<*+&/3*)�273aO�&<G1&93+O52-3+5 0'3�3+0CA(&/) & 2-3K5{N&9Q�5+Q0Y;7�,90CAcG.063�&93*)dYK3H/b3@)+&<A�Y ,90CAcAU(�3�27,d7I)+2-0'3K3LA(&<O�2:(+AkY80C*'(+3@&<*.� ) & 7I);2:3 &92C) & &)* 2-3 & &)*+&/3 ),-:/(53 ),*,(+3�)PB09*@) & / 09*vG.0I)4&93*)+2=79-:-:/�3,(K3,G�27,92-09(+3<Q qL--&<79*,-0/CY'3@),*+27,/)jO�&)G.&/3+O�&/3�,9& 0'3~3,(5, & &/3*)427)+2-&)33 & 0C(+-:OaI.&�7d6'0'2:O�&<OK0C* 06) & &<*MB;243@& ,/24*@,<(+Ac3+,)*+24I1&<O�YKB & &<*@&)66&<*WG10C3H3+24IK--&9Q

w ���

Page 123: Practical Architectures for Survivable Systems and Networks (Phase

2 �:( � �� � " 1 ( � " ( � " 1 �:-�� - 1 � #� � 1 �i� RT6'&/3J2-3�763 79*+, & 2C)4&/,/).(K*+& ) & 7I)�3,7I)42:3 � &)3�79-4- ) & &78I.0r6'&�G+*@2-3�,/24G+-7&<3<Y ) & &<*+&k79*@&k-724D6&)-:/ )40hI.&�Ag7I3E/�7I)+),*.76,G)42:66& )�79*H5'&/),3() & 7I)c*+&)3,(+-C)c>@*@0CA:) & &,/0'3�,/&93*).*,7I)4270'3 09>WG.0rB�&<*)Q %'& &kG+*@2-3�,/24G+-7&L09>F-7&d793�) ,/0CA?A(0'3�A(&9, & 7635243,A 2:3F§H(K3@) 0'3�&�3,(�, &78G+G+*+0C76, & >N0C*W7r660'24O52-3+5 ,90'3�,/&93*).*,7I)4270'3 09>�6879-:(�&<3)QFRT6'&/3O2:>�G1&93�&G).*,7I)4270'3�763+Oe3,(+IV6'&)*,3@2-0'3h79*@&O52 �(,<(+-C)dY ) & &<*@&L79*@& )P/NG52-,d78-4-:/zA?763V/�&d793M/�)�79*H5'&/),3 >N0C* O�&9352=79-¦sA09>=s¢3+&<*M682-,9&T7I)+).76,�DE3<Q ¡ 0C* &[1K79A?GK--&9Y3@&9,)(+*+2C)P/vA?763;795'&)A &/3*)�3H/b3�)4&<Ac3<Y 35&/)PB�0C*,DvA(0'3�2C)40C*@2-3+5X3H/b3@)+&<Ac3<Y;G+(KI+--27,2sPDI&)/ 2-3K>@*,793@),*,(�,G).(+*@&<3)Y7I3+O &/3�,<*M/NG )4&<O �+--&<3?79A(0'3+5"7h56&93�&)*.79-:-:/�(�3�&/3�,<*M/bG5)4&)O �;--&�3H/b3@)+&<A 79-4-'*@&<G+*@&<3@&93*) 0CIV682-0C(K3).79*,56&/).3^>N0C*T7F)+)�7I,�D�Q ¡ (K*@) & &<*,A(0C*@&9Y8B�&d78Dx--273+DE3$78*+&�-724D6&)-:/3@0C(+*+,/&<3 09>�*@&<-72=79I�2:--2C)P/FG+*@0CI+--&)A?3)Y63�0I)§H(K3@)f3+&9,)(+*+2C)P/l6N(K--3�&)*.79I�2:--2C)42-&)3<Q %'& &WGK*+2-35,924GK--& 09>`7d660'24O�273+5X7I)+),*.76,G)42:66& )�79*H5'&/),3243S763 &218)4&/3+3+270'308> ) & &WG+*@2-3�,/24G+-7& 09> O�&)3+24563gO�206'&<*H3+2C)P/ 2-3(,90CAUI52-3;7I)+2-0'3�B;2C) & -7&d793�)LGK*+2:682:--&<56&o763+Og3@&<G;78*.7I)+2-0'3(09>,/0'3�,/&<*+3K3<Q

2 +�" � � - �� � � �!- � ( � � 1 � � � � � � � � �R� 1 1��'- - � ( � �i� � -7) & 0C(+5 & 27)F3+&9&)A?3�)+0�I1&l--&)3,3�09>L73�).*H(�,/),(+*.79-�0C*H5V763�2 � 2-3K5?G+*@2-3�,/24G+-7& ) & 763�7cG & 2:--0C3@0CG & 27,d79-`G+*@2-3�,/24G+-7&9Y ) & &�,90'35,9&<G )�09>�3+,)*,(5).79I+-7&O5&<3+2:5'3+3o763KOK2:A?GK--&<A(&93*).7I)4270'3+3�) & 7I);,<763aI.&J3H(+Ib§@&9,G)4&)O )40�0CG1&93�G1&9&<*'*@&)682-&2B#2:3L6'&)*H/ & &)-4GK>@(+-273e5V7I2-3�273+5 ,90'3��+O�&93�,/&l763+O 2:A?GK*+0r682-3+5(,90'3 �;O�&935,9&�2-3k3H/b3@)+&<A 3,(+*M6 206879I�24-727)P/9Q %'& &�0CG1&93Ns¢I.0d1G+79*.79O5245CA�{ $ &/,/)+2-0'313NQ0�r�V�2:3o7624A(&<O�7I);273�,<*@&d793@2-3+5l3+,)*,(5).79I�2:--27)P/9Q

2 � ( � � � 1 " ( � 1 � � >@(�3+O;78A &/3 ).79-�G106)+&93*)42479-_79ON697I3 ).795'& 08>`A 0CI524--&M,90bO�& 2:3�) & 7I) ) & & ,90bO�&�,<763I1&UG+-47I),>N09*,A 2-3+O5&<G1&93+O�&/3*)x7I3+OO&21 &9,)(5)4&)O 0'3�7I3E/n3H/b3@)+&<A�>N0C*zB & 2-, & 7v3,(527)�78I+--&�2-3*)4&)*,G+*@&/)4&)*&[1 243@),3<Y 2:*,*@&<3,G1&9,G)4206'& 08>WB & &)*+& ) & & ,/0NO5& 0C*@245'273;7I)4&)O_Q %'& & � 7d687�79O;785'&9Y � � �� ��*� � �+����� ������ ��� � ����������� 2:3v3H/bAUI10C--27, 09><) & 7I)aG.0I)4&93*)+2=79-�Q � -7) & 0C(+5 & ) & &O,90'3�,/&<G5)K09>�A(0CI�2:--& ,/0NO5&�IE/2C).3@&<-:>fO�08&<3�3�06)X3@).*@2-,G).-:/n3,G1&d79D 2-3K5e3+&/&<A )40kI.&?7k3�).*H(�,/),(+*.79-SG+*@2-3�,/24G+-7&9Y�27) ,<*@2-&)3�0C( )X>N0C*<) & &(K3+& 08>'79*@, & 27)+&9,/),(+*.78-f3�).*,(5,/).(K*+&<3�2-3hB & 2-, & ,90bO�&v763KOB27),3�&[1 &9,<( )42-063B3�&/&<O 3�06)�,908&21 2:3@)dQ ¡ 0C*) & 7I)�*+&<793+063_Y�2C)�2:3<2-3�,)-4(+O�&)O 273 ) & 243<27)+&<A(2 � 7I)4270'3_Q $ &9,G)4270'3 /NQ � ,90'3+3@24O�&)*,3 ) & &?79*+, & 27)4&/,/),(+*.79-2:A?GK--2-,<7I)4270'3+3 09>$A 0CI524--&�,90bO�&9Q

2�� ( � - �p� 1 " ( � � - � � �J� � &JA?79D6&7UO5243@)+2-3�,G)4270'3 & &)*+&JI1&/)PB�&9&/3eA(0CI�24-7&�,/0NO5&763+OjG10C*@).79I+--&,/0CAcG+(5)4273+5+Qf]A3 ) & &X>N0C*HA &)*M,<793+&8Y1) & &>,/0NO5&�2:3uA(0CI�2:--&8QL]A3 ) & &x-47I)+)+&<*;,d783+&>08>TG10C*@).79I+--&<,/0CAlsGK(5)4273+5+Y*) & & ,90CAcG+(5)+2-3+5XG+-=7I)H>N0C*,Ac3S763+OgB�0C*HDb3�)�7I)+2-0'3K3�79*@&�) & &<Ac3+&<-06'&)3'G.0C*�)�79IK--&uIE/l6824*�).(�&�09>*@0CI+(+3�)fB;2:*+&)--&<3H3�,/0CAcAU(�3�27,d7I)+2-0'3+3)Q %'& & ,9063�,9&)G5) 09> 2-3*)4&)5C*.7F)42-3K5�*,79G�2:O+-:/�O5&<G+-70�/C79I+-7&uB;2:*+&<-7&<3H3-479G5)+0CG+3�3+&9,)(+*+&)-:/hB;27) & 2-3�7 & 245 & -:/O,/0'3��;5C(K*.79I+-7& 273K>@*.793�).*H(�,/),(+*+& ,<--&<79*,-0/�*+&)\b(524*+&)3�715 &[1 24I+-7&3H(+*H68206978I+--&u79*@, & 27)+&9,/),(+*+&8YK783SB�&<-:-¤783�&[1 )+&93+3@2:66&W(+3@& 09> &93�,)*H/bG5)4270'3?>N09* 273*)4&<59*+27)P/9Y ,90'3��+O�&93*)42479-0s2C)P/CY+GK*+&)66&93*)4270'3K09>TO�&/3�2=78-43 09>�3+&)*H682-,/&9Y�763+OK&93 & 763�,/2-3+5c7d687624-479I�24-727)P/9Q

2 + ( � � � �!1 � � "F � " #��t( ( - � -�� �� � � � �J� $b/b3@)+&<A I10 0I).3@),*.79GKG�2-3+5KYW*+&/,90'3 �;5C(+*,7I)4270'3_YF7I3+O273�27)+2=79-72 � 7I)4270'3�79*+&;,909A?A(0'3l3+0C(K*+,9&)3�08>_OK/83;79A(2-,<79-4-0/ 2-3*).*@0NO+(5,9&<Oc6b(+--3�&)*.79I524--2C)427&<3<Q %'& &)3+&zG+*+08s,/&<3H3+&<3�AU(K3@)�79O & &<*@& )40 ) & &o79I.0r66&'G+*+273�,92:G+--&)3<YC7d660'24O�273+5FO�&)G.&/3+O�&/3�,9&M0'3�(�3*).*H(+3@)PB�0C*�) & /�>@(�3�,[s)+2-0'3+79--2C)P/CQ

2 � ( � � 1�� - � ( � ( � �R� �J1 � �� � � �r- �!1 � � %'& &<*@& 243�3+0CA(&�3+09*@) 08> 3�&<5V7F)42:66&'763;78--0C5�09> ) & & $ &9,/0'3+O�`7dB 08> %'& &)*,A(0NON/ 3+79A 27,<3�*+&)-=7I)+2-3+5 )+0�) & &M,90'3K3+&<*M687I)4270'3 08>¤6b(+-73�&<*,79I�24-727)+2-&<3^>N0C*S763V/�5'206'&93c3+&G)08>¤O5&<3+2:5'3�&)*,3 0C* 2:A?GK--&<A(&93*)+&<*,3$76,/)+2-3+5783�7F5C*+0C(KG_Q %'& &)*+&'B;24-:-NI1&'A?763V/U(�3K>N09*+&<3@&9&/3(),*.79O�&/09i¤3) & 7I)�79*@&?-724DI&<-:/ )40a*+&)3,(+-C) 2-3�6N(K--3�&)*.79I�2:--2C)42-&)3 273"3M/N3�)4&)A?3X763+O 2-3 3�&/)PB�0C*HD8273+5eO5&<G1&93+O�273+5K0'3) & &J3,D 2:-4-43�763+OL2-3*)4&)*+&)3@).3;09>�) & &O�&)66&<--09G.&)*,3<Q %'& &<&[1+7I,/)u--08,d7I)+2-0'3 09>�) & &J6b(+--35&<*.78I�24-727)427&<3SAg7d/, & 763+5'&8Y;I+(5);) & &�79595C*+&)5V7I)4&J*@243HDb3u79*@&--24DI&<-0/ )+0cI1&A 09*+&�0C*'-7&<3,3 ) & &3.79A(&9Q

w � �

Page 124: Practical Architectures for Survivable Systems and Networks (Phase

¡ 0C*7�6879*@2-&G)P/ 09>�*@&d793@0'3+3)Y�) & &)3+&(0C*,5C763�2 � 2-3+5aG+*@2-3�,/24G+-7&<3<,d7I3B,9063 ),*+2:I+(5)4&�)+0 2-35,<*+&<793+&)O�3M/N3�)4&)A763+O 35&/)PB�0C*,D"3,(+*M6 206879I�24-727)P/ep 2:> ) & &)/ 79*+&�,/0'3+3@243@)+&93*).-0/ 78G+G+--27&<O�763+O 2:> ) & &)/�79*@&vG+*+09G.&)*,-:/ 2:AlsG+-7&<A(&93*)4&)O_Qum�06)+& ) & 7I)W79I+3@),*.76,G)4270'3_Y�-=7d/'&)*+273+5+Y &93�,<79G+3H(+-=7I)+2-0'3�Y109Ib§@&9,G)HsA09*+2-&/3*)4&<On79G+G+*@0V76, & &)3<Y_7I3+OG10C--27,)/VsPA(&9, & 7I3�243HA 3@&<G;78*.7I)+2-0'3a79-:-.,<763L,90'3*),*+24IK(5)4& )+0�5C*+&<7I)4&)* 2-3*)4&)*+0CG1&<*,79I�24-727)P/9Yb*@&<(+3,79I�2:--27)P/9YK-70'3+58s)4&)*,A 3H/b3@)+&<A &)6'09-:6879I�2:--27)P/9Y$7I3+O 3+&/,<(+*@27)P/9Q %'& &vG+*@2-3�,/24G+-7&<3 09>o3+&)G;79*,7I)4270'3D09> ,/0'3�,/&<*+3K3l763+O -7&d793�)G+*@2:6824-7&<5'& ,<763k79-43@0�3,(+I+3�)�763*)+2=79-:-:/�2:A?GK*+0r6'&�0CG1&<*,7I)4270'3;79-¤3+&/,<(+*@27)P/�763+O�*+&)--2479I�24-727)P/9Q

%'& &)3+&G+*+273�,92:G+--&)3 ,d7I3e79-:3+0�,/0'3*).*+2:I+(5)+& )40 24AcG+*+0r66&<O�763;79-0/b3+243)QT]A3�G;79*@)+2-,)(+-=79*)Yb>N09*,A?79-�A(&/) & 0NOK3,d7I3�I.&?(+3+&)OD)40�763+79-:/ � &?*+&)\b(524*+&)A &/3*).3<Y�3HG.&/,92���,d7I)+2-0'3+3)Y�763+OB24AcG+--&)A &/3 ).7I)4270'3+3)Q �M0rB&26'&<*)Y�3,(�, &763;78-:/b3+&)3�,<763�I1&?59*+&d7F).-:/n3+24AcG+-72�� &)O�IE/O) & &?(K3+&(09>�3�).*,(5,/).(K*.79- ,90'35,9&<G ).3p &)3,G1&9,92479-4-0/�-=7d/6&<*+273+5+Y79I+3�).*,76,/)+2-0'3_Y�&93�,<79G+3,(K-=7I)+2-0'3_Y$G.0C-72-,2/Es¢A &/, & 763�2:3,A 3@&<G;79*,7I)4270'3_Y�7I3+O�O�0CA?762-3"3+&)G;79*.7F)42-063_Q ¡ 0C*>&[1Es79AcG+--&8Y ) & &cAg78G+G�2-3K5C3�79A 063+5a-=7d/'&)*,3>08>L>N0C*HAg79-:-:/k3,G1&9,/2�� &)O�79I+3�).*.7I,/)4270'3+3<2-3B$Kyo] �|3 ��27&<*.78*+, & 27,d79-t &)66&<-70CG+A(&93*)10 &/) & 0bO�0C--0959/ }��V�C�r�79*@& ,d79G;78I+--& 08>�273+O+(�,/2-3+5 &/3�0C*HA 0C(K3j3+24AcG+-72�� ,<7I)4270'3+3(2-3 ) & &>N0C*HAg79-¤G+*+0809>�G+*+08,9&)3,3o>N0C*'-=78*,5'&F3M/b3@)4&)A?3)Q

� GKG+*+0V7I, & &<3M) & 7I)uG+*@0CG1&<*,-0/a79O+OK*+&<3H3�) & &xA(0CI�2:--&2s ,90bO�&FG+*@0CI+-7&<A�O�&)Ag7I3+Oe3@245'3�2�� ,d7I3 )M2:A?G+*@0r6'&2sA(&93*).3�2-3�) & &�273K>N0C*,A?7I)+2-0'3 273K>@*.783@).*H(�,/),(+*+&8Q %'& & 3�06)+2-0'3<09>KG.09*@)�78I+--& ,/0CA?GK(5)4273+5;243�,<-7&d79*H-:/J7'>N0C*@,92-3K5>@(�3�,G)4270'3 063�3H/b3�)4&<A 79*@, & 27)+&9,/),(+*+&)3<Y�7I3+OB,<763 *+&)3,(+-C)>273"3@245'352�� ,<763*)�2:A?GK*+0r6'&)A &/3 )�09>�) & &?3,(+*M6 206Vs79I�2:--2C)P/�09>.) & &M&93*)42:*+&u3H/b3@)+&<A 763+O 3�&/)PB�0C*HD ,/0CA?GK--&21�2:>.,90'3+3@243�)4&93*),-:/c*+&�5 &9,G)4&<O 2-3 ) & &z79*+, & 27)4&/,/),(+*+&8Q

]PO�&<79-4-0/CY�A 0bO�&)*+3�3+09> )PBL79*@&K&/3+5'273�&9&)*+2-3K5h3 & 0C(+-:O�&/3�,909A?G;783,3�) & &)3+&K0C*,5C763�2 � 2-3+5eG+*+273�,92:G+--&)3<Yf79-0s) & 0C(+5 & 2-3 G+*.7I,/)427,9&O27)L2:3v>@*+&)\b(5&93*).-0/�3506)�(+3+&)O 2-3 7�3,(��(,/2-&93*),-:/ O�2:3+,92:G+--273�&<O A?763�3�&)*�)40J)�79DI&79OK68763*).795'&<09>�) & &)AkQ

]A3aO�24*@&9,G)o*+&<3HG.063+3+&<)40�) & &c�d�C�C� = � � � ���*����� � � ? ���z*+&<G10C*�);09> ) & &�mW7I)+2-0'3+79-_y;&<3@&d79*@, & q0C(�3bs,92:-�} /C����Y97I3 &2i 09*@)�243 GK*+08,9&9&)O�2-3K5;)+0'O�&)66&<-70CGx7I3+OXGK*+0CAU(K-45V7I)+&T7'3+&G)�09> � &935&<*.78-4-:/ � ,/,9&)G5)4&)O�$b/b3@)+&<Ac3$ &/,<(+*@27)P/"��*+2-35,924GK--&<3?{ � � $�$K�S�?{ & )+).G����C��B&)I_Q|A(27)<Q &)O+(��83@&9,)(+*+2C)P/+��B'B'Bz�85V793H3,G_��� & ),A?-=�2Y�763KO )40 &<3Zs)�78I+--2:3 & 763h]A3*)4&<*@3;7I)+2-0'3;78-�]A3K>N0C*,A?7I)+2-0'3O$8&9,<(K*+27)P/ ¡ 0C(53+O;7I)+2-0'3�{@] ^ $ ¡ �2Q 0e763V/O09>) & 0C3@&cGK*+2-35,924GK--&<379*@&�*@&<-7&)68763*) )40l3,(K*H682:6879I�2:--2C)P/v793'B�&<-:- Y+I+( )W78*+&�,<-7&d79*H-:/ 3�06);&9350C(+5 & IV/ ) & &)A?3@&<-:66&<3)Q

� � � � � ���� ��� �� � ��� � 5��� � � ���

$ &26'&<*,79-LA?76273"3�).*,(5,/).(K*+2-3K5 ,90'35,9&<G ).3�79*@& 08>oG;79*@)+2-,)(+-=79*�273*)4&<*@&<3�)dY &<76, & 09>�B & 27, & & 793 ) & &?G.0I)4&93bs)42479- 09>;2-3KO+(�,9273+5 ,/0'3+3@24O�&)*.79I+-7&gO�2:3+,/24G+-72-3�& 0'3�79*@, & 27)+&9,G).(+*@&<3�&)A?G+-70r/ 273+5 ) & &g3�).*H(�,/),(+*.79-�,90'35,9&<G ).309> $ &/,/)4270'3 /NQ0�CY�763+OD) & &<*@&<IV/ &/3 & 763�,/2-3+5�3H(+*H68206978I�24-727)P/CQ %'& & 2-3*)4&/3*)�09>;) & 2:3U3+&/,/)+2-0'3 2:3>)40�3H(+AlsA?79*+2 � &F6879*+270C(+3u79G+GK*+0V76, & &<3<Y¤3+0CA(&<09>$B & 2-, & 79*@&<,90CAcG.&G)4273+5cB;2C) & 0'3�&X763�06) & &<*)Y 06) & &)*,3M09>$B & 2-, &A?7r/�I1&U(+3@&<OO2-3 ,/0CAUI�273;7I)+2-0'3_Q %'& &)*+&l79*@&>,<-7&d79*H-:/L).*,79O�&/09i�3�) & 7I)WAU(+3�)JI.&�,90'3K3+24O5&<*+&)OO,d79*@&)>@(+-:-:/I1&)>N0C*@&>&<AxI;79*,D 273+5�0'3�G;78*@)427,<(+-479*u79*+, & 27)4&/,/),(+*.79-�O�24*@&9,G)42-063+3op ).*,79O�&908i�3J78A 0'3K5g3,(K*H682:6879I�2:--2C)P/L243Ms3,(5&<3<2-3�,)-4(+O52-3+5v3@&9,)(+*+2C)P/CY`*+&)--2=78I�24-727)P/CY;>@(�35,/)4270'3;79-727)P/9Y�G1&<*H>N09*,A?763�,9&8Y 763+Oh793H3,(+*,763�,/&(08>�79GKG+--27,d7I)+2-0'3I1& & 7d682-0C*)Q

2�� ��1�� � "F � " #��� -�� �R" - � �%1 �i� ��27&<*.78*+, & 27,d79-z3@).*H(�,/),(+*+&)3L,d763 I1& 09>�5C*+&<7I)v6879-4(5& 2-3~3M/N3�)4&)AO5&<3+2:5'3_Y�7I3+O�79*+&?G;79*�)42-,)(+-=78*,-:/ 24AcG.0C*�)�763*)�2-3 O5243@),*+2:I+(5)4&)O 3H/b3�)4&<Ac3<Q �M2-&)*.79*@, & 2-,<79-fO524*+&/,/)+0C*H/3�).*H(�,/),(+*+&)3�{�793 2-3 0�(+-7)+2-,<3e}��C�8�W763+O � 3�201+�cGK*+0r6824O�&e763 24AcG10C*@).763*) 0C*H5V763�2 � 273+5"3�).*H(�,/),(+*+&8Y7I24O�273+5�2-3�3+&/3+3+2:I+--&�3+,/0CG�2-3K5 09>�3;79A(&<3z763+OeGK*+06)+&9,/)+2-0'3�Q ��27&<*,79*+, & 27,d79- -70 ,�D 273+5l3@).*,7I)4&)5'2-&)3U}�� � �{N3�06)+&<OK2-3 $ &9,G)42-063"�CQ �NQQ3C��79*@&�(K3+&)>@(K- Y 3�06).79I+-:/�2-3�7d6'0'2:O�2-3+5lO�&<79O+-70 ,�DE3<QS�S79*+270C(+3 & 27&<*.78*+, & 27,d79--47d/'&<*H3;09>$GK*+06)+&9,/)+2-0'3�79*@&<,90'3+3@24O�&)*+&)O 273�3H(+I+3@&<\E(�&93*)WI+(+-4-7&/)+&<OL27)+&<Ac3<Q

w � �

Page 125: Practical Architectures for Survivable Systems and Networks (Phase

2�� � ( - 1 " - � ( � �J( � � � � %'& &O3�06)4270'3 09>�-=7d/'&)*+&)O *@2-3+5C3 08>xG+*@06)4&/,/)+2-0'3 >N0C*HA &)O 7�I+793+2:308> 0k(K-7)427,<3<2-3��r�C�43NY B & &<*@&() & &c>@(53�,/)+2-0'3;78--27)P/ 09>'7I3E/�G+79*@)+2-,<(K-=79*F*@2-3+5aBL793XGK*+06)+&9,/)+&<Oh>@*+0CA,/0CAcG+*+0CA(243@&�{�7I,9,92:O�&93*).79-o793UB�&<-4-o783(273*)4&93*)+2-0'3;78-��X*@&<3,(K-7)4273+5�>@*+0CA ) & &j>@(�35,/)4270'3;79-727)P/ 09>W79-4-09(5)4&)*,A(0C*+&U*@2-3+593<Q�0�(+-7)+2-,<3W(+3+&)O &/245 & )<,9063�,9&/3 ),*+27,�*+2-3K5C3<Y_B & 093+&l*+&)--&)687635,9&�)40a3H(+*H682:6879I524--2C)P/2:3,/0'3+3+2:O�&<*@&<Oa>@(+*@) & &<*2-3K$ &/,/)4270'3 /NQ � Q0�CQT]A3L&<3�)�79I+-7243 & 2-3+5�) & &FGK*+0CG1&<*'-47r/6&<*@2-3+5+YN3+&)G;79*.7F)42-063�09>GK*+2:682:--&<56&<3o763+Ok79-:--08,d7I)+2-0'3 09>$--&<793@)uG+*@2:6824-7&<5'&F3 & 0C(+-:OeI1&�09I+3+&)*H6'&)O ) & *+0C(+5 & 0C(5)<Y�B;2C) & ,<-7&d79*H-:/O5&<--273�&d7F)4&<O O�0CA?762-3+3)Y;,d79*@&)>@(+-:-:/�O�& ��3�&<O 763+O &/3K>N0C*@,9&<O & 27&<*,79*+, & 27,d79-z-=7d/'&)*+273+5+Yu763+O~-70C5'2-,<79-,/0CAcG;79*@),A &/3*).3<Q � -7) & 0C(+5 & ) & &)*+&UA?7d/aI.&x79G+G+-72-,d7F)42-063+3'>N0C*uB & 2-, & ,9&/3*).*.78--2 � &<OkA &/, & 763�2:3,Ac3A?7d/gI1&F>@(�3�,G)4270'3;79-:-:/c79G+GK*+0CG+*@2=7I)+&9Y &)6'&/3K) & 0C3@&�A(&9, & 763�243HA?3LAU(+3@)oI1&J79IK--& )+0cI1&FG & /b3+27,d79-:-:/09*F--0C562-,d78-4-:/gO�243�).*@24I+(5)+&<O 273 0C*,O�&)* )40�7I)@)�76273 & 2:5 & 7d687624-479I�24-727)P/9Q�{ ¡ 0C*�&21K79AcG+--&8Y & 7d682-3+5 063+-:/7�3@2-3+5C-7&J79(5) & &93*)+2-,d7F)42-063�3@&<*M6'&<*M243 2:-4-¤79OK68243@&<OK2-3aO�2:3@).*@24I+( )4&<OL&/3E682:*+0'3+A(&93*),3<Y;G;79*�)427,<(+-479*,-0/ 273) & &vG+*@&<3@&93�,/& 09>uA?763V/�(K3+&<*H3 0C*U*+&)3+0C(K*+,9&)3<Q � ��0rB�&)6'&)*<Y ) & &�&)3@).79I+--2:3 & A(&93*)�08>zO5243@),*+2:I+(5)4&)OGK*+06)+&9,/)+2-0'3hO�0CA?76273+3J*+&)\b(524*+&)3X3HG.&/,92479- ,d79*@& 273"O5&<3+2:5'3_Y^I.&/,d79(K3+& 08>�-=7F)4&<*,79-TO�&)G.&/3+O�&/3�,927&<3�273& 0C*+2 � 0'3*)�78-_79I+3�).*,76,/)+2-0'3�763+OL) & &�*@&<3H(+-7)+2-3+5lG106)4&/3 )+2=79-�-=7I)+&<*.78- ,909A?G+*@0CA(243+&)3<Q

2 + 1 " � ���r- � $ 1�� ��1 � �k � � � � � �i� %'& & ,90'3�,/&<G5),(;79-:-:/c3+2:A?G+-7& & 2-&<*,79*+, & 2-,d78-¤3�).*,(5,/).(K*+2-3K5�,90'3bs,/&<G5)�09>z7 ).*,(K3@)4&)OJ,90CAcG+(5)+2-3+5nI+793+& 0'3D)+0CG 09>z7nD6&)*+3�&)- 243>2-3+3�).*,(5,/)4206'&vO5&<3,G527)4& 2C).3 & 24O+O�&/3,/0CAcG+--&[152C)427&<3v7I3+O�273 & &)*+&93*)a-724A(27)�7F)42-063+3<Q % *.79O527)4270'3;79-�,9&/3 ),*.79-72 � &<O % q $KRSq�79*@, & 27)+&9,/),(+*+&)3& 7r66&j*+&)--2-&)O & &d7d6824-0/B063J) & & & /bG.06) & &<3@243�) & 7I)l7n*+&)-=7I)+2:66&<-:/"3,A?79-:-f3@&9,<(K*+27)P/ D6&<*@3�&<- )+0C5'&G) & &)*B;2C) & 7�).*H(+3@)+&<OB,/0CAcG+(5)4273+5jI;793@&n{ % q�£'� ,90C(K-4OO,90CAcG+-7&/)4&)-:/ &93�,<79G+3,(K-=7I)+& ) & &lA &)O�2=7F)42-063 09>78-4-`3+&/,<(+*@27)P/ 243,3H(�&<3)Y_3+0 ) & 7I) 3�06) & 2-3+5 0CG.&)*.7I)+2-3+5 0C(5),3+24O5&>09> ) & & % q�£ 763KO ) & &XD6&<*@3�&<-�,90C(+-:O,/0CAcG+*+0CA(243@&F3+&/,<(+*@27)P/9Q � & &)*+&d783�) & 243;243 0'3K-:/ & /bG.0I) & &G)42-,<79-4-0/vG10C3,3@24I+-7&J>N0C*'3@),*+2-,G)Hs¢3+&93K3+&xAx(+-0s)+24-7&)6'&)-T3+&/,<(+*@27)P/ {¥763+O ) & &/3B0'3K-:/ 273�,909A?G+-7&/)+&<-:/ 2-3h7 3�&G)PB0C*HD6&)OD&93V6824*@0'3+A(&93*)[�[Y�A(0C3@)<0I) & &)*,)*+2C)42-,<79-�3+&/,<(+*@27)P/"G+*+09G.&)*@)427&<3�,d763�3506)xI1&g3@0 &935,d79G+3H(+-=7F)4&<O�(53+--&)3,3>) & &gDI&<*+35&<-�7I3+O % q�£�79*@&-479*,56&9Q %'& 243'79GKG+*+0V7I, & *,(�3+3 273*)40UO�2 �(,<(+-C)42-&)3&)3,G1&9,92479-4-0/ 2-3 & 245 & -0/(3�&/)PB�0C*,DI&<OK&93V6824*@0'3+A(&93*).3)Y273�B & 2-, & ) & &)*+&L,d7I3 I1&L3�0"3@2-3+59--& % q�£ � ) & & 3506)4270'3 09>J7 ),*,(+3�)4&<O�,90CAcG+(5)+2-3+5�I+793+&�AU(+3�)I1&>&/27) & &<*�&218)4&/3+O�&<OO)40g*+&<\E(�2:*+& ).*,(K3@)PB�0C*@) & 2-3�&)3,3<09>S79-:-�,90CAcG.063�&93*).3)Y 0C*�&<-:3+&UI1&�79I+-7& )+0j76,[s,/0CAcA 0bO;7I)+&X3M/N3�)4&)A?3�09>�G106)+&93*)42479-�(53 ),*,(+3�)PB09*@) & 2-3�&)3,3<Q 0k(+-C)42:--&)66&<-^3+&/,<(+*@27)P/�7I3+OnAU(+-C)42:--&)66&<-273*)4&<59*+27)P/ ,90'3*),*+0C-:3M,<763 & &<-:Gk-724A(27)'78OK6'&)*,3+&�&)i.&9,G).3�)+0�B;27) & 2-3a3+&/,<(+*@27)P/�--&26'&<-:3X{�763+OK,909A?G;78*@)HsA(&93*),3�� p 273�,<-:(+O�273+5WA?79--27,9270C(+3^763+Ol76,/,92:O�&93*)�78-KA(243,(K3+&'793TB�&<-:-+793�24AcG+-=763*)+&<O % *+0�§,763 & 0C*,3@&<3)Q]A3?79O+O527)4270'3_YV��79(+- �79*,56&<*u} � 39�8��3 & 0rBo3 & 0rB~O5243+,)*+&G)42-063;79*H/U76,9,/&<3H3,9063 ),*+0C-:3 ,d763l>@(+*@) & &<*�-724A(27)) & &G.0I)4&93*)+2=79-¤O;79A?795'&�09> % *@0w§,763 & 0C*H3+&<3)Q� 3�&09>10C(+*TA(0C3@)�24AcG.09*@)�7I3 )�,90'3K3+24O5&<*.7F)42-063+3 ) & *+0C(K5 & 0C(5)�) & 2:3T*+&)G.0C*�) 243 ) & 7I)�) & &o79GKG+--27,d7I)+2-0'3>@(53�,/)+2-0'3;78--27)P/O2:3X>@(�3KO;79A(&93*)�79-�Y 3�06)u§H(+3@)�) & &�0CG1&<*,7I)4273+5n3M/N3�)4&)A?3�DI&<*+35&<-43l7I3+OD).*H(+3@)PB�0C*@) & /&[18)4&93K3+2-063+3<Qg� 3�& 09>�) & &lG+*+2:Ag78*H/e>¥7I24-4(K*+&<3 09>) & &l3+&9,)(+*+2C)P/�D6&)*+3�&)-SA(0r6'&)A &/3 ) 273O) & &a�r�C�C�83BL793 ) & 7I);27);0r6'&)*+&/3+O�0rB&)O ) & &DI&<*+35&<-43u763KO % q�£L3)Q

2 + 1 �R � - � ( � $ 1�� ��1 � �i� £�76,�D 2-3K5 09i�>@*+0CA 0 � $�D6&)*+3�&)-43)YTyo(+3 & IV/ }��C�9�KY`�V�9����G+*+09G.0C3@&<O"7Ax(�, & 3+2:A?GK--&<*S3+&)G;79*,7I)4270'3gDI&<*+35&<-�{¥79-43@0>,d78-4--&)Ov763 243@0C-=7I)+2-0'3cD6&)*+3�&)-�� ) & 7I)LO�08&<3 3�0I) & 273+5xA(0C*+&) & 763�G+*+0r6824O5&fO�09Ag762733+&<G+79*.7I)+2-0'3 0'3B & 2-, & *+&)3+0C(+*@,9&fAg763+795'&<*H3�,d763XI.&SI+(�2:-7) ) & 7I)�&)i.&9,/)+2:66&<-:/2:3+0C-47I)4&kO�2:i.&<*@&93*)a(+3@&<*,3�763KO O52:i.&<*+&/3*)j(+3+&)3<YJ7I3+O (+G.063 B & 2-, & 79G+G+-72-,<7I)4270'3NsP-47d/'&<*c3+08> )PB�79*@&,<763�I1&jI+(�24-C)dQ $N(5, & 7n3@24AcG+--&g79*+, & 27)4&/,/),(+*.79-f3@),*,(�,G).(+*@&aB�0C*HDb3�66&<*H/B3�2-,/&<-0/">N0C*>,9&93*),*.79-72 � &)O7I3+OJ3�0'3�3�&G)PB09*,D6&)O 79GKG+--27,d7I)+2-0'3+3�B;27) & &)--&)A &/3 ).79*H/B243@0C-=7I)+2-0'3�*+&<\E(�2:*+&)A &/3 ),3<Q � -7) & 0C(+5 & 2732C).3@&<-:>;2C)�O�08&<3 3�06)l3H(+G+G10C*@) 35&/)PB�0C*,DI&<O 3M/N3�)4&)A?3)Y�) & & ,90'3�,/&<G5)(09>W7n3+&)G;79*,7I)4270'3�D6&<*@3�&<-;,<763I1&>&[18)4&93KO�&<O�IV/ & 7d682-3K5v*+&)3+0C(+*@,9&�A?763;7956&<*,3;) & 7I)FB�0C*,Dk76,<*@0C3,3WO�2:i.&<*@&93*)F3M/N3�)4&)A G+-=7F),>N0C*HA?3

w ���

Page 126: Practical Architectures for Survivable Systems and Networks (Phase

7I3+O ) & 7I)L6824*�).(;78--2 � & ) & & 35&/)PB�0C*,D 2-3K5U>@(�3�,/)+2-0'3+79--2C)P/CQ �M0rB&26'&<*)Y�) & &W*+&<3@0C(+*@,9&FA?763;7956&<*,3fAU(+3�)) & &<Ac3+&)-:66&<3�I1& ).*,(K3@)PB�0C*@) & /�B;2C) & *@&<3,G1&9,G) )40 ) & &M35&/)PB�0C*,D 2-3K5+YE793 2-3�) & & ,d783+&;09>+0���$UD6&<*@3�&<-:37I3+O % q�£L3<Q

2 � � (:�! - � ( � 1 "F J � � � � � ����"F ��� �%1S/ #��� � � � - � � � -0/ ( � - � � �� � � �i� ¡ 24*@&)BL79-4-:3<Y59(;79*,OK3<YV763KO�06) & &<* 2:3+0C-47I)4270'3A &/, & 763�2:3,Ac3 ,d763>2-3�,)*+&d783+&) & &).*H(+3@)PB�0C*�) & 273�&<3H3 09>�3H/b3@)+&<Ac3 ) & 7F)) & &)/ &935,d79G+3H(+-=7F)4&�0C*zA &)O�2=7I)+&xI1&/)PB�&9&/3_Y`IE/kG;79*�)42C)42-063�2-3+5c3H/b3�)4&<Ac3763+O 35&/)PB�0C*,DE3<2-3n3H(�, & 7BL7d/J) & 7I)g3+0CA(&�--24A(27)+&<OJ2-3*)+&<*.7I,/)4270'3+3(,d763 3@)42:-4-'I1&eG1&<*HA 2C)+)4&)O (�3KO�&<* ,d79*@&)>@(+-:-:/J,9063 ),*+0C-:--&)O,/24*@,<(+Ac3@).763�,9&)3<Q $8&9,/)+2-0'3��CQ �<3506)4&)3 ) & 7I)S7I;793+27,o*+&<\E(�2:*+&)A &/3 ) 273?A(&<O�247I)4273+5FI1&/)PB�&9&/3v*+&)5'2-0'3K308>�G.0I)4&93*)+2=79-:-:/j(�35&<\E(;79-�).*,(K3@)PB�0C*@) & 2-3�&)3,3�2:3�)40 &93+3H(+*+&>) & 7I)W3+&93K3+27)+2:66&�2-3K>N09*,A?7I)4270'3aO�0 &)3 3�0I)-7&d79D 09(5)F7I3+O ) & 7I) % *@0w§,763 & 09*,3+&)3F763KO 06) & &<* & 79*,Al>@(+-�&)i.&9,G).3zO�0�3�06)z3+35&d79DL2-3�QoRT18)+&93+O�273+5) & 7I) )+0v3,(K*H682:6879I�2:--2C)P/CY.) & &�2:3+0C-47I)4270'3kA(&9, & 763�243HA?3WAU(+3@)<&/3+3,(K*+&�) & 7I)76,G)42-063+3 2-3 0'3�&�*+&)5'2-063,<763�3�0I)�,909A?G+*@0CA(243+&�) & &v3,(K*H682:6879I�2:--2C)P/ 09>u763�0I) & &)*x*+&)5'2-063 76,)*+0C3H3>) & & 243@0C-=7I)+2-0'3hI10C(�3+O;78*H/CQ{ � 3 &d79*H-:/ &[1K79A?GK--& 09>'7a5C(;78*,OB2:35'2:66&93hIE/ }��C�C�����[Q ��0rB�&)66&<*<Y$G+*+06)+&9,G)42-3K5e795C762-3+3�)�O�&93�2479-4308>$3@&<*H6827,9&�7624A(&<O�7I) ) & &<243@0C-=7I)+2-0'3gA &/, & 763�2:3,Ac3 ) & &)A?3@&<-:66&<3M243o7U>@(�3+O+79A &/3*)�79- 3H(+*H682:6879I524--2C)P/*@&<\E(�2:*+&<A(&93*)<Q

2�� 1 ���&7( � � � �t(�( - � -�� �� � � � �� #"O$�� � �i� q0'3+3@24O�&)*.79I+-7&X3H(+*H68206978I�24-727)P/ ,<763eI1&U76, & 2-&)66&<O 20>3M/b3@)4&)A?3x79*+&cI10 06)+&<O 0C*X*@&<I10 0I)4&<Oh>@*+0CA 3�0'3;79-C)4&)*.79I+-7&l3+0C(+*@,9&)3U3,(�, & 793xy�� 0 0C*x78(5) & &/3*)420s,<7I)4&)Ohq�tF3<Q %'& 2:3FG+*@0�682:O�&<3763�78-7)4&)*+3;7F)42:66&�)+0�,<*M/NG )40C5C*,79G & 27,�2-3*)+&<5C*@27)P/K, & &9,�DE3�) & 7I)JO�&G)4&9,G)(53�&21NG1&9,/)+&<O 3M/b3@)4&)A 78-7)4&)*.7I)+2-0'3K3<Q %'& &<*@& 2:3X78-43+0k7a*+0C-7&l>N09* 063�,9&[s¢Bo*+2C)�79IK--&lA &)A 09*H/nA(&<O52=7KY>N09*l79(+O�2C)�).*.7I24-43l7I3+O -70C5C3)Yf7I3+O >N0C*�I+76,�DE(+G+3 ) & 7I)(,d7I3 G1&<*HA 2C)l*.79G�2:O�*+&9,/0r6'&<*M/ {�793 2-3J) & &��-4763NsZ�FO524*+&/,/)+0C*H/x3@).*H(�,/),(+*+&8YVB & 2-, & 79-4-70rBo3$6824*@),(;79-;7I,9,9&)3,3 )40�7JO�24*@&9,G)40C*M/U3@),*,(�,G).(+*@&W783 09>_7I3E/3HG.&/,92�� &<OL)42:A &d�2Qo{ $ &9&?}�� � �8�_>N09*z7�,)*H/bG5)4095C*.79G & 2-,79-C)4&)*+3;7I)+2:66&9Q �

2 � ��� -�� � 1 1 � & � 1 " � ���!- � � � ��� -�� � 1 1 � & � �'- 1 � ���!- � � � � �i� 0���$�763+O 0�� ]g{ $ &/& $ &9,[s)+2-0'3��CQ �NQQ/C� &d7I, & >N0C*@,9&c3@).*H(�,/),(+*+&(0'3O) & &c*+&)3,(+-C)4273+5a3H/b3@)+&<Ac3U763+O 3�&G)PB0C*HDE3<YTG;78*@)427,<(+-479*,-0/ 20>7I3E/a*@&d79-`783,3,(K*.763�,/&>2:3uO5&<3+2:*+&)O�{�783�273 % q $NRfq £L�?3H/b3�)4&<Ac3��[Q ¡ 0C*;&21K79AcG+--&8Y�) & &�O�&)3+24563 09>T756&93�&)*.79-¦sPG+(+*HG.093+&�0 � $n3M/N3�)4&)A O�&<A?763+OK3 ) & & & 2-&<*,79*+, & 2-,d78-�-47r/6&<*@2-3+5�08> ) & &U3M/N3�)4&)A 763+O ) & &,/0CAcG+--&G)4&�&935,d79G+3H(+-=7F)42-063 08>2C).3J3+&/,<(+*@27)P/�DI&<*+35&<-f763+O % q�£ { )40�G+*+&26'&93*)�,90CAcG+*@0CA 2:3+&)3F>@*+0CA09(5).3@24O�&d�2Q�] )u79-:3+0�*+&)\E(�24*@&<3'3@),*+27,/)o3+&)G;79*,7I)4270'3 09>^O�0CA?762-3K3'76,<*@0C3,3 0���$vI10C(�3+O;78*+2-&)3<Q %'& &(+3@&08>T76310���$j3H/b3@)+&<A *+&)\E(�24*@&<3;&21NG+-72-,92C)'3+&)G;79*,7I)4270'3L09>$*@0C--&)3u763+OaO+(5)+2-&<3)Q

2 � ��� -�� � 1 1 � � � � � �� � � �r- � � � � � ��� 1��J1�� � ���S1 � � ��� � %'& & 0�� � ,90'35,9&<G )fO5& � 3�&)O 273$8&9,/)+2-0'3��CQ �NQ|�JB;2C) & *+&)3,G1&9,/) )40�5'&/3�&<*,79--2 � &<OcO�&)G.&/3+O�&935,9&F78G+G.&<79*,3 )40I1&W7JG10rB&)*H>@(+-�G.0I)4&93*)+2=79-3�).*H(�,/),(+*.79-S762:OB273"O�&)3+2:5'3�2-3K5e763KOB,9063��;5C(+*@2-3+5k3H/b3@)+&<Ac3U763KOD3�&/)PB�0C*HDb3XB;27) &h& 2:5 & -:/ ,<*+2C)427,d79-3H(+*H68206978I�24-727)P/�*@&<\E(�24*@&<A(&93*).3)Q � 3>3�06)+&<OB) & &<*@&9Y ) & &g(+3@&�09>'56&93�&)*.79-72 � &)O O�&)G.&/3+O�&935,9&j*.7F) & &)*) & 763�) & &'3@),*+2-,G) � 1 � 1�� � � � �t( �e*+&)-=7I)+2-0'3�7d660'24O+3$3+0CA(& 09> ) & & ,)-=793H3+27,d79-bG+*+09I+--&)A?3�783,3+08,9247I)4&)OB;2C) & ) & &z3@).*@2-,G)LG;78*@)42479- 0C*HO�&<*@2-3+5C3 2-3 & &<*@&93*) 273 0�� ]�Qb] )'79-:3+0 &93�,/0C(+*.785'&<3) & &WO5&)6'&)--0CGKA &/3 )09>),*,(+3�)PB09*@) & /kA &/, & 763�2:3,Ac3�) & 7I)W79*+&�24AcG+--&)A &/3 )+&<OK0C(5) 09>�--&)3,3M).*,(K3@)PB�0C*@) & / ,90CAcG10'3�&93*),3<Y_7832:-4-:(+3@),*.7I)+&<OjIV/j6879*+270C(+3;&21K79AcG+--&)3o5'2:66&93 273 $8&9,/)+2-0'3h�CQ �NQQ3NQ %'& 2:3;,90'3�,/&<G5) 243oG+(+*H3,(�&)Oe>@(+*�) & &)*273K$ &9,G)4270'3 /bQ �KQ �NQ

2 + 1 � 1 " - � 1 & -�� � � -0/ ( � - � �J1 � � � "F �!- 1 " - � �%1 �i� � 3�&79GKG+*+0V7I, & )+0�&<3�)�79I+-7243 & 2-3+5 & 245 & -0/c3,(+*Zs68206978I+--&3H/b3�)4&<Ac3763+O 3�&/)PB�0C*HDb3�273V6'0C-06'&<3F79*+, & 2C)4&/,/).(K*+&<3 2-3kB & 2-, & 3H(+I+3H/b3�)4&<Ac3c{ &8Q|5KQ:Y¤3+&<*M6'&)*,37I3+O &/3+ONs¢(+3+&)*WG+-47I),>N0C*HA?3.��79*+&�3@),*+2:G+G.&)O 08> 3�06)M0'3+-0/�) & &924*o(�353�&9&)O�&<On>@(�35,/)4270'3;79-727)P/gI+(5)W79-43@0

w � �

Page 127: Practical Architectures for Survivable Systems and Networks (Phase

) & & ,/0C*,*@&<3,G10'3+O52-3+5U(53+O�&<3@24*,79I+--&z6N(K--3�&)*.79I�2:--2C)42-&)3 ) & 7I)�) & &W3,(+G1&<* 5;(�0C(+3'>@(�35,/)4270'3;79-727)P/ &/3 ).7624-:3<Q%'& 243 ,d763(2-3l3@0CA &;,<793+&)3fI1&u76,9,/0CA?GK--243 & &<O�B;2C) & 09i�s ) & &[sP3 & &<-0>�G+*@0CG+*@2-&/).79*H/U3H/b3@)+&<Ac3<YbI+(5)SAg7d/I1&F7I, & 2-&26'&<OaA(0C*+&�&)i.&9,G)42:66&<-0/?B;2C) & 0CG1&93bsPI10r1g3H/b3�)4&<Ac3 2-3?B & 2-, & ) & &F(�3�35&9,9&)3,3,79*H/v>@(53�,/)+2-0'3Ns78--27)P/�,d763kI.&XA 0C*@&�&<793+2:-:/a*@&<A(0�66&<O_Y¤763+O ) & &�>¥79(+-7)P/j>@(53�,/)+2-0'3;78--27)P/v*+&<GK-=76,/&<Oap *+&)3,(+-C)4273+5 2733HG.&/,92479-0s¢G+(+*,G10C3@& ,90CAcG10'3�&93*),3z3HG.&/,92���,d79-:-:/g79O;79G5)+&<OL)40�) & &924* 273*)4&93KO�&<Ok(+3+&)3<Q

2 + 1 � 1 " - � 1 & -�� � � -0/ ( � - � �J1 � � � � + � "I �!-e1 " - � �%1 �i� � 3�& &[1+78A?G+-7& 09>z7 ) & 2-3bsA,<-72-&/3 )U79*Ms, & 27)4&/,/),(+*+& 243<09>fG;79*�)427,<(+-479*�24AcG.09*@)�7I3�,9& & &<*+&lB;27) & *+&<3HG.&/,/)�)40L3�&9&)O+3X>N09*JAU(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+&7I3+OkAx(+-7)+24--&26'&)-0sP3H(+*H68206978I+--&z3H/b3@)+&<Ac3<QM$N(�, & 763e78G+G+*+0C76, & &/3 ).7624-:3oI+(�24-:O�2-3K5�AU(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+&3M/b3@)4&)A?3T763+O�3�&G)PB09*,DE3�-=79*H5'&<-0/�0C(5) 09>�3@2-3+5C-7&2s¢--&)66&<- ,<-72-&/3 )�3H/b3�)4&<Ac3o{�>N0C* &[1K79A?GK--&9YI09i�s ) & &2sP3 & &<-0>,)--27&93*)F3M/N3�)4&)A?3.�2Q]A3�3,(�, & 763�78*+, & 2C)4&9,G).(+*@&9Y_Ax(+-7)+24G+-7&X3@2-3+5C-7&2s¢--&)66&<-f{(0 $ �^� &93+ONs¢(+3+&)*F3H/b3�)4&<Ac378I+--&()40�76,/,9&)3,3�).*H(+3@)PB�0C*@) & / 3+&)*H66&<*,3 ,<763�G+*+0r6824O�&gAU(+-7)+24-7&)6'&)-�3+&9,)(+*+2C)P/�763KO�AU(+-7)+24-7&)6'&)-�3,(+*Zs68206978I�24-727)P/CQ %'& 243 3�0I)42-063 & 793jI1&9&/3 &[1NG+--0C*@&<O IV/ 06) & &<*H3<YM2-3~G;79*�)427,<(+-479* ) & &�79*+, & 27)4&/,/),(+*.79-78G+G+*+0C76, & O�&<3@,<*@24I1&<OaG+*+&2682-0C(+3H-:/?IV/v��*+08,/)+0C*'763KOam�&<(KAg76353h}��K�d�8� 7I) $Kyo]�YKI;793@&<OL2-3gG;79*@) 0'37I3 &<79*,-72-&<*�mM&)B�,d793�).-7&Jq0'3�35&9,/)+2-0'3gt 243�).*+2:I+(5)+&<O $ &9,)(+*+& $b/b3@)4&)A 78*+, & 2C)4&9,G).(+*@&�08> yo(+3 & IV/v7I3+Oyu763+O5&<-4-¤}��C�C�8�U7I)�mM&)B�,d793�).-7& ) & 7I)T7d6'0'2:O+3T3+09A &�09> ) & &LG+*+0CIK--&<Ac3T783,3+08,9247I)4&)OxB;27) & A(0'3�0C-727) & 2-,Ax(+-7)+24--&26'&)-0sP3@&9,)(+*+2C)P/?DI&<*@3�&<-:3W763KO % q�£L3)Q %'& 243o79G+GK*+0V76, & 243'IK*+0V79O5&93�&)O 2-3 ) & 243 , & 78G5)4&)*<Q� 3�79-C)4&<*@3;7I)+2:6'&L79G+G+*@0V76, & )+0J7WG10C*@)+2-0'3�08> ) & & 0 �aGK*+0CI+-7&<A 243�O�&<3@,<*+2:I.&)O�IV/ �763+5KY ¡ *+0C3@, & &<*)Y7I3+O 0 0C3,DI0rB;27) � } � � �8�E7F)�) & &SmW7d6879-Ey;&<3+&<79*+, & �`79I.09*.7I)+0C*H/9Y87I3+O<243^79-43@0 ,90'3K3+24O5&<*+&)O_Q %'& &Lmzy �B�0C*HDn762:A?3J7F)JB & 7I)<243�273 &)i.&9,G)x7 & 2:5 & -0/kO5243@),*+2:I+(5)4&)O 0���$ % q�£ 2-3�,/0C*,G10C*,7I)4273+5v7v6879*+27&/)P/08>�&2i 0C*�).3 )40(2-3*)+&<5C*,7I)4& 0 $�� 3H/b3@)+&<Ac3<Y 2-3�,)-4(+O52-3+5l7 0'3�&[s¢BL7r/Vs(5 0rB�79*+, & 27)4&/,/),(+*+&?{ &8Q|5KQ:Y^}���3w��Y�7��(+AcG?}¦� � �w�E7I3+O�$b]Zm % y � 0'3�) & &�3+&)*H66&<*^3+24O5&9Yw763+O<)PB0zq'� % $Es¢I;793+&)Ox3MB;27)4, & &<OB0C*HDE3@)�7F)42-063+3063 ) & & ,)--2-&/3*)X3@24O�&8YT79-:--0rB;2-3K5�) & &)A )+0 09G.&)*.7I)+&g7I)XO�20i &)*+&93*)X--&26'&<-:3�08>�AU(+-C)42:--&)66&<-�3@&9,<(K*+27)P/K�[Q� 3�&K09>�) & & ,<--27&93*).3(243�) & & $ )�79*H--245 & )c]A3*)4&)*.76,G)4206'& � 273+D¤}¦� � � YLO�&)66&<--09G.&)O IV/H) & & � (+3�).*.78--2=7I3t<$ % ��Q %'& &>06) & &<*M243 ) & &�q'�<$K�S� { q0CAcAU(�3527)P/��FG1&93 $80C(+*+,/&U��*+095C*.79A � �(,/&r� $EB;27)4, & &<O� 0C*HDb3�)�7I)+2-0'3�Y'O�&)66&<--09G.&)O~IE/ 0k] % yuRoYL763+O 79GKG+*+0r6'&)O~>N0C*g(+3@&nI1&/)PB�&9&93 � 35,<-=783,3+2�� &<O 7I3+O% 0CG $ &/,<*+&G)x-7&)66&<-43�08>,)-=793H3+2���,d7I)+2-0'3_Q %'& &l-=7I)@)4&<*J3@, & &<A(&cAg79DI&<3<&218)+&93+3@2:6'&c(+3@& 09>�2-3*)+&<5C*@27)P/, & &9,�DE3x7I3+O�78(5) & &/3*)42-,<7I)4270'3_Y_G+79*@)+2-,<(K-=79*H-:/k76,<*@0C3,3 0���$�I.09(�3+O;79*@2-&)3<Q �M0�B�&)66&<*)Y 3�&/27) & &<*�) & &mzy ��B09*,D�3�09*M$8)�79*H--2:5 & )'79O+OK*+&<3H3+&)3�) & & 273*)4&<59*+27)P/?G+*@0CI+--&)A?3 ) & 7I)u76,/,90CAcG;763V/j(KGEBL79*HO 5 0rB>@*@0CA�7--0rB�&<* )40X7 & 2:5 & &<* 0���$l--&)66&<-Kp ) & &�0���$EsA063+-:/U6827&)B 79-:--0rBo3�*.78A?G;7I3 )f76,)\E(�243@27)4270'3 09>% *+0�§,763 & 0C*H3+&<3o7I3+OL06) & &)*�G1&<3@)oGK*+0C5C*,79Ac3<Q %'& &mzy �O&)i.0C*�) 243'7I24A(&<OvG+*@24A?79*+2:-:/l7F)'79-:--0rB;2-3+5) & &J>¥76,92:--&J*@&d79O�273+5(09>$-70rB&)*MsP-7&)66&<-�2-3K>N09*,A?7I)4270'3_YA5 0rB;2-3+5(0'3+-0/v>@*+0CA ) & &�3+&)*H6'&)*�)+0() & &�,)--27&93*)dY7I3+OaO�0 &)3;3�06)u*+&)G+*+&)3+&93*)W7l>@(K-4- 0 � $ &93V6824*@0'3+A(&93*)dQ

2 �� � � &�"S� ��1��'- 1�� ��& � � 1�� � "I �!-e1 " - � �%1 �i� ��35&�09> ) & &UA 093@)FGK*+0CA(243@2-3+5?79*+, & 27)4&/,/),(+*.79- ,90'3bs,/&<G5),3L>N0C* ) & &u>@(5).(K*+& 273E660C-:66&<3L7x3+&)--&9,G)4206'&2s ).*H(+3@)PB�0C*@) & 2-35&<3,3o78*+, & 2C)4&9,G).(+*@& ) & 7I)L*@&<G+*@&<3@&93*).3 ) & &7I3 )+27) & &<3@243�09>uA(0'3�0C-727) & 2-,l(+3@&<* 0CG1&<*.7F)42-3K5n3H/b3@)+&<Ac3k{N) & &j-=79*H5'&<3�)l7I)�) & &jA 09A &/3 )U3+&9&)A?3�)+0I1& � 273+O�0rBo3J�8�C�C�V�[Y.3;78A &)-:/CY1&93KONsP(+3@&<* 09G.&)*.7I)+2-3+5?3H/b3@)+&<Ac3 ) & 7F)J79*@&x3@),*+2:G+G.&)O 09>�(�353�&9&)O�&<O>@(53�,/)+2-0'3;78--27)P/9YVA 273�24A?79- 2-3g3@2 � &9YN763+O ).7624-70C*+&)O?G+*@&9,/243+&)-:/�)+0>) & &�3�&9&)O+3 09> ) & &/24*S(+3+&)*,3<Q�]A3?3,(�, &7 ,/0'3�,/&<G5)<Y ) & &<*@&K2:3U3+2:A?GK-:/h--&)3,3�3+08> )PB�79*@& )40n>¥762:-L763KO�-7&<3H3�3+09> )PBL79*+& )+0�I.& ,/0CA?GK*+0CA(243@&<O_Q%'& & , & 79-:--&/3+5'& ) & &93B243�)+0�79-:--0rB ),*,(+3�)PB0C*�) & / 3M/b3@)4&)A?3U763+OD3�&G)PB09*,DE3�)40eI1&gO5&)6'&)--0CG1&<O 09*,/0'3��;59(+*+&)OUB;27) & 0C(5) & 7r68273+5 )40 ),*,(+3�) ,9063+3@)+27).(5&93*) ,90CAcG10'3�&93*),3�) & 7F)$B�0C(+-4O�350C*,A?79-4-0/ & 7d6'& )+0I1&;).*,(K3@)PB�0C*@) & /?(�3+O5&<*,/0'3V6'&/3 )+2-0'3+79-�78*+, & 2C)4&9,G).(+*@&<3)Y+763+O()40�I.&W79I+-7&;)+0x*@&<-:/�0'3 & 2:5 & -0/�).*H(+3@)MsB�0C*�) & /U3@&<*H66&<*H3 08>�6879*@2-0C(K3$3,G1&9,/2=79-¦sPG+(K*,G10C3+&�D 273+O+3^p &<76, & 09>�B & 2-, & O50 &)3 3�06) 3�&/&<O�)40 & 7r66&o7>@(K-4-:/Vs(5 &<O+56&<O�I+-70V7I)PBL79*+& 0CG1&<*,7I)4273+5J3H/b3�)4&<A�Q�R$1K79A?GK--&<3 08>�5'&/3�&<*,79--2 � &)O�O�&<G1&93+O5&93�,/& 2-3UB & 2-, &

w � �

Page 128: Practical Architectures for Survivable Systems and Networks (Phase

) & 243oA(245 & )oI1&XG10C3H3+24IK--&�79*+&�5'206'&93 2-3 $ &9,G)4270'3"�9Q��NQQ3NQ %'& &��F*.76,)--&�m�&G)PB09*,Dkq0CAcG+(5)4&)*�2:3u763&[1K79A?GK--&�09>�B & 7I)uAg7d/jI1&9,/0CA(& ,/0CAcA 0'3KG+-=76,/& 2-3L) & &>@( ).(+*@&9Y�7cI+79*+&[sPI10'3�&<3o(+3@&<*M0CG1&<*.7F)42-3K53M/b3@)4&)A ) & 7F)u79-4-70�Bo3�76,9,/&<3,3;)40 3�&G)PB09*,D �;-7&J3+&<*M6'&)*,3F7I3+O � &)I�>@(�35,/)4270'3;79-727)P/9YKG1&<* & 79G+3o(�3+O�&)*,/&<*�)�76273�&93K>N09*+,9&<79I+-7&W*+&)3@),*+2-,G)4270'3+3�3H(�, & 793�) & 0C3+&�08> ) & & � 7d687X� 24*@),(;79-+0e76, & 273�&9Q�]¢>`3H(�, & --08,d79-09G.&)*.7I)+2-3+5X3H/b3@)+&<Ac3 & 7d6'&�0CG1&93bsPI10r1g3+08> )PB�79*@&up 2:O�&d78-4-:/�3�0'3+G+*@0CG+*@2-&/).79*H/(0CG1&93bsPI10r1g3+08> )PB�79*@&{ $ &9,G)4270'313NQ:�d�V��p ) & 7F) & 793oI.&/&93 ,<79*+&2>@(+-4-0/g66&/)+)+&<OK)40 &93+3H(+*+& ) & 7F);27)o3.7F)4243 � &<3;2C).3;3�&9,/&<3H3.79*M/*@&<\E(�2:*+&<A(&93*),3<Y_A?763V/ 08> ) & &�, & 78*.76,G)4&<*@243�)42-,X6N(K--3�&)*.79I�2:--2C)42-&)3;&93E(+A(&<*.7F)4&<OO273 ) & 2:3F*+&)G.09*@)�,<763I1&SAg79O5& )+0WO�2:3.79G+G1&d78* 0C*�)40zI.&/,90CA(&,/0'3*).*@0C-4-479I+--&�7F) ) & &&/3+ONsP(K3+&<*�3H/b3@)+&<Ac3<QT]A3>,90CAUI52-3;7I)+2-0'3B;2C) & B;2:*+&)--&<3H3 ,90CAcAU(�352-,d7F)42-063+3<Y*) & & ) & 273NsA,)--2-&/3*)L(+3@&<*'G+-47I),>N09*,Ac3 & 7d66& &)3,3@&93*)42479-4-0/g(�3K--24A(27)+&<OG106)+&93*)42479- Q %'& &k��*@0 ,G)40C*ZsZm�&)(+A?763�3�79*+, & 27)4&/,/),(+*+&)3g79*@&a763H&21K79AcG+--& 09>W7 ) & 273NsA,)--2-&/3*) 0���$78*+, & 2C)4&9,G).(+*@& 2-3 B & 27, & 0���$ 2:3�7I)@)�76273;79I+-7&?B;27) & 3�0O&93+ObsP(+3@&<*H0���$ (+3+&)*�3H/b3@)+&<Ac3?7I3+OJ3�0*@&<3H(+-7)+2-3+5�&/3+ONsP(K3+&<*M,90r66&<*@)�, & 76353�&<-:3<Q

2 � * �p� � " �!- � � " ( � 1�� � - � � � � � � - 1 � - � ��" - � �%1 � � %'& &'m�&2B,<793@),--&�y;&9,/0r6'&<*M/�£L-70 ,�DJA(&9, & s7I3�243HA } � /bYW�r�NYF�d� � �J*@&<G+*@&<3@&93*).3�7 *.7F) & &)*jO�2:i.&<*@&93*)�79G+G+*@0V76, & )+0�3H/b3@)+&<A 3@),*,(�,G).(+*@2-3+5KY�273B & 2-, & 79-7)+&<*@3;7I)4206'&vGK*+0C5C*,79Ac3l79*+&a79( )40CA?7I)427,d79-:-:/ 273V6'0CDI&<O 273�7�3H/b3@)+&<A?7I)427,vB�7d/ B & &/3�&)66&<*) & &G+*+2:Ag78*H/vGK*+0C5C*,79Ac3uO50 3�0I)zON/ 3+79A 27,d79-:-:/g3.7I)+243H>�/ ) & &/24*o*,(�3bs )42:A &J*@&<\E(�2:*+&<A(&93*),3<QL]A3K) & 7F)78G+G+*+0C76, & Y;79-C)4&)*+3;7I)+2:66&<3 ,<763aI.&J7I3 )+2-,/24G;7I)+&<O 3;7F).(+*,79-4-0/cB;2C) & 273 ) & &�0�66&<*,79-4-¤3H/b3@)+&<A 3@),*,(�,G).(+*@&)+0x7I,9,909A?A(0NO+7I)4&u79*HI�27),*.79*M/U>¥7624-:(+*+&)3 0C*f7I)+).76,�DE3<YK*@&<3H(+-7)+2-3+5 2-3?76,9,/&<G5).79I+-7&�0r6'&)*.79-:-�3H/b3@)+&<A I.&[s& 7r68270C*zp >N0C*�&21K79AcG+-7&9Y >¥7624-¦sP3,78>N&9Y�>¥7624-¦sP3+08> )dY�>¥762:-0s & 79*,O�Y¤>¥762:-0sP3@&9,)(+*+&8Y_>¥7624-¦sP(�3+3@&9,)(+*+&8Y`>¥7I24-0s B;27) & sA(2-3524A?79-0sP7r68762:-478I�2:-C2 )P/CY 0C* 2-3 ) & & ,90'3*)+&218)�09>509(+* G+*+&)3+&/3 )�5'0V78-43<Yd>¥7I24-0s¢3,(+*M682:6879I+-7&9Y)B;2C) & B & 7I)+&)66&<*O5& � 3�2C)4270'3 09>�O�&<5C*,79O�&)Oe3,(K*H682:6879I�2:--2C)P/?A?7d/jI1&76,9,/&<G5).79I+--&(�3KO�&<*;) & &5'206'&/3K,/24*@,<(+Ac3@).763�,9&)3<Q

2 � � � � � 1 � � 1 �:- � � � � � ( � - � ( � � � � � � -�� ��" - � �O1 �i� %'& &>,/0'3�,9&)G5) 08>�7 � �� � � � ��������� �� ���� �� � �$� � � �� (� � �� �D���$���)���������&����{�0eR�],]�Y`} �r�8�=� & 793'I1&9&/3aG+*+0CG10C3@&<OK2-3�) & &�,<*+2C)427,d79-12-3K>@*,793Ms),*,(�,G).(+*@&<3 ,909A?AU(53�27)P/ )40�&/3+3,(+*@& ) & 7I)�3@0CA(& &<3H3+&93*)+2=79-+>@(�35,/)4270'3;79-727)P/B�0C(+-4O ,/0'3*)42-3E(�& )+0<&21 243�)O5&<3,G527)4&u7J*+&<793+063;79I+-7&u*,763+5'& 08>_3,(K*H682:6879I�2:--2C)P/�) & *+&<7I).3$p 7I)@)�76,�DE3<Y80C(5).795'&)3<YV>¥7624-:(+*+&)3<Y'&/3V6 2:*+0'3bsA(&93*).79-�O�243�).(+*HI;763�,/&<3)Y�763+O"3+0 063_Q � 3K>N09*@).(53;7I)4&)-:/9Y�) & &<*@& 243<,/0'3+3+2:O�&<*,79I+-7&?O�&)I;7I)+& 0r6'&)*�) & &O5& � 3�2C)4270'3+3�08> � �� � ����7I3+O ��������� �� ����)p 783TB&)-4-+783�*+&9,/0C5'3�2C)4270'3�09> ) & &'G+*+09I+--&)A?3 273 & &)*+&93*) 273),*H/82-3K5M)+0z>N08,<(+3�0'3U7u3+273+5C--&�(�352:6'&)*,3,79--0kR�]H]�QC� 3�&�09>5) & &LA(0C3�) ,/0CAcG.&)-4--273+5o79G+GK*+0V76, & &<3�)+0�) & &3H(+*H68206978I�24-727)P/ 09> ,<*+2C)427,d79-�,9063 ),*+0C-�763+O ,90CAcAU(�3�27,d7I)+2-0'3K3M273V6'0C-06'&<3 0C(5)Hs 09>=sPI+763+OK,90'3*).*@0C-43M) & 7F)78*+&K3�06)v3@0�6b(+--35&<*.78I+--&e793 ) & & 3�09*,A?79-'>@(�3�,/)+2-0'3+79--2C)P/CQ ��0rB�&)6'&)*<Yu(�3+-7&<3,3gO�&93�2479-0s 09>=sP3@&<*M6 27,9&7F)+)�7I,�Db3 ,d763~I1&nG+*@&)6'&/3*)4&<O�Y�) & 243g3@&9&)A 273+5 I1&93�& ��)aAg7d/�I1& 3�&<5C7I)4&)O_Q�£&9,<79(+3@& 09>JB;24O�&)-:/6879*M/82-3+5k*+&<\E(�2:*+&)A &/3 ),3�{ &)3,G1&9,92479-4-0/�B & &93�3H(+*H68206978I�24-727)P/O243�2-3*).*@0NOK(�,9&)O��2Y 2C)�2:3X6'&)*H/�(�3+--2:D6&)-:/) & 7I)u7�3+273+5C-7& 0eR�],]�,90C(+-:OaI.&�76,/,9&<G )�79I+-7&9Q���0rB�&)66&<*<Y?0eR�]H]�*+&)Ag76273+3 273 )+&<*@&<3@)+2-3+5 273k7U68795C(5&3@&93+3@&�793o7U5C(�2:O�2-3+5U79*+, & 2C)4&/,/).(K*.79-!,/0'3�,/&<G5)<Q ¡ (+*�) & &)*,A(0C*+&8Y5,/0'3V6'&93*)+2-0'3;78-4-:/gI;793@&<O10eR�],]P3u79*@&-724DI&<-:/()40c3@),(+AUI+-7&3+&<*@2-0C(K3,-:/�2-3 ) & &�G+*@&<3+&/3�,9&�09>�3,(+I+3M/b3@)4&)A?3zB;27) & \E(�&)3@)4270'3;79IK--&?{¥A(2-3�2:Ag78- ���),*,(+3�)PB09*@) & 2-3�&)3,3 ) & 7I)?79*@&K&/3+O�0rB�&<O B;2C) & Ag7w1 2:Ag79-F{¥I+-72-3+O;��).*,(K3@)dQ � -C) & 0C(K5 & 0eR�],]P3v7I3+OA(2-3524AU(+A�s ),*,(+3�)U78*+, & 2C)4&9,G).(+*@&<3g79*+&L3�06)(3�&/,9&)3,3.78*+24-0/ 2-35,90CAcG;7I)+24I+-7&�2-3�G+*@2-3�,/24G+-7&9Y ) & &2/�Ag7d/I1&>273�,909A?G;7F)424IK--&�2-3kG+*.7I,/)427,9&Jp 5'206'&/3 ) & &�2-3 & &<*+&/3*)J(�3*).*H(+3@)PB�0C*@) & 2-35&<3,3�08>�3+0vA?763V/K09> ) & &7d68762:-=79I+-7& ,90CAcA &)*+,/2=79-S3H/b3@)+&<A:,/0CAcG.0'35&93*).3�7I3+O ) & &vO50C(+I5),3l79I.09(5)�24AcG+*@0�66&<A(&93*).3>2-3D) & &>@( ).(+*@&9Q � O�2:3+,)(+3,3@2-0'3 09>S3+0CA(&�09> ) & &c79-C)4&)*+3;7I)+2:66&<3J763KO"G+*@0CI+-7&<Ac3WB;27) & 3H(�, & 763�78G+G+*+0C76, &2:35'2:66&93D273 }�� � 3r� Q � &?O�0 3�06)X*+&<G1&d7F)�) & &<A & &)*+&9Y$I.&/,d79(+3@& ) & & 0eR�]H]�,90'3�,/&<G5)>243�A 09*+& 09>7lI+( ��� B�0C*,O ) & 763k7l*+&d78--27)P/9Y 2-3a--2:5 & );09>�) & &JB;24O�&�3,G1&9,G).*H(+A 09>$*@&<\E(�2:*+&<A(&93*),3W3,(KI5)4&/3+O�&<OeIE/3H(+*H68206978I�24-727)P/CQ

wFw �

Page 129: Practical Architectures for Survivable Systems and Networks (Phase

2 � �! � � � " #�Y" ( �:-�� ('� - 1 ( � � � %'& &B�&<-4-¦sA&)3@)�78I+--2:3 & &)O ��&<-4OL09> ,9063 ),*+0C- 3M/b3@)4&)A?3�09i.&<*,3'6879*@2-0C(+3)+&9, & 3524\E(�&<3�) & 7F)�,<763xI1&�(+3+&)O>)40�2-3�,)*+&d783+& ) & &S3,(+*M682:6879I�2:--27)P/F76, & 27&)6879I+-7& 273X3M/b3@)4&)A?3)Y'2-35,<-4(KO�2-3+53�)�79I524--2C)P/J09>>N&9&)O+I;76,�D�Q $ &/& }��C�9�w�F>N0C* ) & &�(+3@& 09> ,9&)*@)�7I2-3 ,9063�,9&)G5).3j>@*+09A ,9063 ),*+0C-M) & &/0C*H/273 O5&)6'&)--0CG52-3+5"3,(+*M6 206879I+--& 2-3K>N09*,A?7I)4270'3�3H/b3@)+&<Ac3<Q $N(�, & ,/0'3�,9&)G5).3 ,90C(+-:O 273 G+*@2-3�,/24G+-7&k78O+O3@245'352�� ,<763*).-:/()40�) & &�79*+, & 2C)4&/,/).(K*.79- 3�).*,(5,/).(K*+& 09>T7�3H(+*H682:6879IK--&J3H/b3�)4&<A�Q

� & 7I)�243 & 2:5 & -:/UO�&<3@24*.78I+--&M2-3() & &z--0'3+5�*,(53�243 ) & &�&<3�)�79I+-7243 & A &/3*)09> 7X>¥79A(24-:/>09> -70C5'2-,<79-+3M/N3�)4&)A79*@, & 27)+&9,/),(+*+&)3�&/3�,909A?G;783,3+273+5 ) & &lI1&<3�)x783,G1&9,/),3<09>�) & 0C3@&?78G+G+*+0C76, & &<3<) & 7I)�79*+&l*@&d79-:-:/e79G+G+-72-,d78I+--&)40�3H(+*H68206978I�24-727)P/CQ ¡ 0C*�&21K79AcG+-7&9Y$B�& ,d763J,/0'3�,9&/2:66& 09>o3H/b3@)+&<Ac3�B & 0C3+&a78*+, & 2C)4&9,G).(+*@& 243XI;793+&)OJ0'3A(2-3�2:A 2 � 2-3K5K),*,(+3�)PB0C*�) & 273�&<3H3cB & &<*+&aG10C3,3@24I+-7&9Y�(+3@2-3+5 0���$�D6&<*@3�&<-:3c763+O % q�£L3(2-3 0���$�3+&<*M6'&)*,3B & &)*+&FAU(K-7)42:--&26'&<-+>@(53�,/)+2-0'3;78--27)P/�243 &<3,3@&93*)42479- Yb(+3@2-3+5X3@).*@2-3+56&93*)�O�09Ag76273?3@&<G;78*.7I)+2-0'3cB & &<*@&WAU(+-C)42:G+--&(+3@&<*,378*+&>35&9,9&)3,3,79*H/�{¥I+(5)FG.&)* & 79GK3 3�06) 2-3 063�&2s¢(+3+&)*FG.&)*,3@0'3;79- ,90CAcG+(5)+&<*,3 0C*�273nO�&)O�2-,<7I)4&)OnB0C*HDCs3@).7I)4270'3+3Lp 06) & &<* ) & 763K) & &�-=7d/'&)*+&<OK243@0C-=7F)42-063 09> ) & &�(+3+&)*o>@*@0CA 79GKG+--27,d7I)+2-0'3+3)Y+79GKG+--27,d7I)+2-0'3+3f>@*+0CA) & &�0CG1&<*,7I)4273+5J3H/b3�)4&<Ac3<YK763+Oc3+0 0'3��[Yb(K3+2-3K5XOK/83;78A 27,u-70V79O�273+5�09>�79(5) & &93*)427,d7I)+&<O?A 0CI524--&,90bO�&'>@*+0CA).*H(+3@)+&<O�3+2C)4&<3)Y�763+Oa(+3@2-3+5 &21NG+-72-,/27).-0/(,90CAcG.&/3+3.7F)42-3K5c3M/b3@)4&)A 3@),*,(�,G).(+*@&<3oB & &<*@&<) & 7I)u79GKG+*+0V7I, & ,<763& 7d6'& & 245 & G;7d/609i�3)QM$N(�, & 7I3n79*@, & 27)+&9,/),(+*+&�A(245 & )u76,G).(;79-:-:/a7I, & 2-&26'&�) & &�O�&<3@24*+&)O &2i &/,/).3�09>T*@0CI+(+3�)0eR�],]P3�� & 0rB&26'&)*<Y!) & &x5'0V78-�08>S76, & 2-&2682-3+5"0kR�]H]P3 243uO�&)*+2:687I)+2:66& � 2C)zB�0C(+-:OnI1&�) & &U*+&)3,(+-C) 09> & 7r68273+5O�&26'&<-70CG1&<Oe3H(�27).79I+-7&F3H/b3@)+&<A 79*@, & 27)+&9,/),(+*+&)3<Y�763+OL2:3 3�06)uA &<763�273+59>@(+-:-:/?76, & 27&)6879I+-7&JIE/�27).3@&<-0>ZQ

0k(+-C)427,<3�{ $8&9,/)+2-0'3 � *@, & $8),*,(�,G)[�2Y�� $+�<$�{ $ &9,G)4270'3 $809> )�R 3+5E�[Y1$ &d7w� 2-&2B { $ &9,G)42-063 � &93;t &)G��2Y�7I3+OR:0eR�y � �`t { $ &9,G)42-063 3NQ:��3C�X79*@&�&21 ,/&<-4-7&93*) &21K79AcG+-7&<3�09>;) & &j*+0C-7& 09>uO�&)3+2:5'3�3@),*,(�,G).(+*@&9YSI.&/,d79(+3@&O�&26'&<-70CG1&<*,3�09> &d76, & 08>�) & 0C3+&�3H/b3@)+&<Ac3M)+0 09Dv5C*+&<7I)uG;76273+3 )40?79OK68763�,/& ) & &X3�)�7I)+&�08>�) & &x79*�)M2-3L,90'3bs3@),*,(�,G)4206'&J3@),*,(�,G).(+*@&�763+Oa5'080NOv3@09> )PBL79*+&�&/3+5'2-35&9&<*@2-3+5�GK*.76,G)42-,/&9Qu{ $ &9& ) & &m�06)+&)B�0C*@) & /ayM&2>N&<*@&93�,/&<3,92C)4&)OK273 � G+G1&93+O5201�tUQ �

� � � � � ���� ��� �� � ��� � ��� � � � ��� �

� ������� + 1 " � �O1 � � 1�� - � � � + � � - 1 �%'& &F68793�)oAg7�§@09*+27)P/(09>�,/0CAcA &)*+,92479-�G.&)*,3+063;79-0s ,90CAcG+(5)+&<*�0CG.&)*.7I)+2-3+5x3H/b3@)+&<Ac3x{N3�06).79I+-:/9Y8) & 0C3@&F>@*+0CA0 27,<*+093+09> )��g79*+&n7�§@0CD6&nB & &/3 ,90'3+3@24O�&)*+&)O B;2C) & *@&<3,G1&9,G)L)40D3�&G)PB09*,D 3@&9,<(K*+27)P/~763+O 7d687624-479I�24-727)P/9Q$ 0CA(& 08> ) & & � 3�2¦1�GK-=7I)H>N0C*,Ac3 & 7d6'&jA?7I).(+*@&<OB)+0 ) & &vG10'2-3*)x7I)xB & 27, & &d79*H-:/g§@0CDI&<3l79I10C(5) � � 3�2013+&/,<(+*@27)P/��lI.&/2-3+5U763 0d1N/bA(0C*+063a79*+&W7U--&<3H3�3+&)*+270C(+3 ,/0'3�,9&)*+3_Y�78-7) & 0C(+5 & ) & &J79I524--2C)P/�)40UA(243@,90'3 �;5C(+*@&� 35201j3M/b3@)4&)A?3M243o3�)424-:-_7�,<*@27)+2-,d78-�G+*,76,/)+2-,d78-_G+*+09I+--&)AkQ

]A3 ,90'3V6'&/3*)42-063;79- ,9&93*),*.79-72 � &)O�AU(K-7)42:--&26'&<-¦sP3@&9,<(K*+&�3H/b3�)4&<Ac3<Y�27)<243<,)(+3@)+0CAg78*H/ )40K)�79-:Dn79I10C(5) ) & &3+,/0CG1& 09> ) & &�3+&9,)(+*+2C)P/�G.&)*+24A(&/)+&<* ) & 7I)(&93�,/0CA?G+793,3@&<3 ) & & &/3K>N0C*+,/&<A(&93*)�08>FAU(+-C)42:--&)66&<-'3@&9,<(K*+27)P/p )P/bG�2-,<79-4-0/n7aAU(+-C)424-7&)66&<-0s¢3+&/,<(+*@27)P/kD6&<*@3�&<-SG+-:(+33+0CA(&k{ 09> )+&93h-=79*H5'&r�F79A(0C(�3*) 09> ).*H(+3@)+&<OB,/0NO5& 273) & & % q�£WQ �M0rB&26'&<*)Y�3,(�, & 7e3@&9,<(K*+27)P/"G1&<*+2:A &G)4&)*xO�08&<3�3�06)�&/3�,d78G+3,(+-47I)4& ) & &v3@&9,)(+*+2C)P/B,/0'3�,9&)*+3+3)Y0'3+-0/a7l3+&<-7&9,G)4&<Ok>N&)B�79IK3@).*,76,/)+&<O 2:3,3H(�&<3z*+&<-47I)4273+5�)40?AU(+-C)424-7&)66&<-_3@&9,<(K*+27)P/9Q � 3z3+080'3k793uB�&>,/0'3+3@24O�&)*O�2:3@).*@24I+( )4&<O~3M/b3@)4&)A?3a7I3+O & 245 & -:/H3�&G)PB0C*HD6&)O�&/3E682:*+0'3+A(&93*),3<Y�) & &n3@08sA,<79-4-7&<O 3@&9,<(K*+27)P/ G.&)*+2:A &G)4&<*)P/bG�2-,<79-4-0/ &/3�,90CAcG;793H3+&)3eA?7�§@0C* ,909A?G10'3�&/3 ),3e7I3+O >@(�35,/)4270'3;79-727)P/ {¥3H(�, & 793K,90CAcG�2:--&<*H3<Yu*,(�3bs )42:A &--2:I+*.78*+2-&)3<Y_IK*+0rBo3+&)*,3<Y�IV/8)+&9,/0NO�&(2-3*)+&<*,GK*+&/)+&<*H3<Y^3+&<*M6'&)*,3<YT763+Oh(�3*).*,(K3@)PB�0C*@) & /h*@&<A(06)4&l3+2C)4&)3��2Y^763KO 2733+09A &;,d783+&<3fAg7d/l7I,/).(+79-4-0/xI1&�&)3,3@&93*)42479-4-0/U(�3EI10C(�3+O;78I+--&�p &<3,G1&9,/2=79-:-:/XB & &93 27) 2-35,<-4(KO�&<3 ) & &�&/3 )+24*@&]A3*)4&)*+3�&G)dY &)66&<*H/ )+&<-7&<G & 063�&<2-3�) & &B�0C*H-4O_Y;7I3+O &)--&/,/).*@0CA?795'3�&G)42-, 2-3*)4&)*H>N&<*@&93�,/&J>@*+0CA�(�3;763*)427,92:G;7I)4&)O3+09(+*+,/&<3<Q

wFwFw

Page 130: Practical Architectures for Survivable Systems and Networks (Phase

]A3X79-4-C3H(�, & 3M/b3@)4&)A?3_p B & &/) & &<*�,9&/3*).*.78--2 � &<O 0C* O�2:3@).*@24I+( )4&<OFp B;27) & 7I3E/F5'&93�&)*.79-727)P/�08>KG+(K*,G10C3+&8Y) & &<*+& 243 3�0n3,(K*H682:6879I�2:--2C)P/�G.&)*+2:A &G)4&<* 2-3 ) & &?3+&/3+3+&�) & 7I)x79-4- ,<*@27)+2-,d78-S3H(+*H68206978I�24-727)P/ 2:3,3,(5&<3�,<763 I1&,92:*+,)(+A?3@,<*@24I1&<O_Q�mM&)66&<*@) & &<-7&<3H3<Y+3@&)6'&)*.79-.09> ) & &W3�).*H(�,/),(+*.79-�79*@, & 27)+&9,G).(+*@&<3,/0'3+3@24O�&)*+&<O 2-3 $8&9,/)+2-0'3 /NQ|�79*@& ,d78G;79I+-7& 09>`G+*@0r6 2:O�2-3K5x3,(K*H682:6879I+-7&W3M/N3�)4&)A?3o763KO�3�&/)PB�0C*HDb3;273 ) & &J79I+3@&93�,/&�09> 3+&/,<(+*@&�0CG1&<*.7F)42-3K53H/b3�)4&<Ac3f>N09* &/3+ONs¢(+3+&)*f3M/N3�)4&)A?3)Q �M0rB&26'&<*)Y+79( ) & &/3 )+2-,<7I)4270'3?I1&9,/0CA(&<3S766&<*M/ ,)*+2C)42-,<79-�2:3,3,(5&9YN793�O�0 &)3) & & 35&9&<O�>N0C* ).*H(+3@)PB�0C*�) & /aI�24-47I)4&)*.79-�79(5) & &93*)427,d7I)+&<O�G;7I) & 3<Q

� ������� � � " � � � - � ( � � � � 1 � � � �� 1 1��'-

� �������#��� � �� �� ��� �� � ��������� � � � � � ���H��� � �#� � ���� ���� ��� ��� �*���#����� ��� ���������+, � ��������������� ����� � ��������� � � � ��� ���Q������������+, � � ����������� � ��� ������� �����#� ��� ����� � )+).*@24I+( )4&<O?IV/cyM0C56&<*mM&9&)O & 79A )40g£L(5).-7&<* �`79A?GK3+0'3_Y¤763+On7I)+),*+24IK(5)4&)OnIV/e£f(5).-7&<*�`79AcG+3@0'3 )+0jyM095'&<*zm�&/&<ONs& 79AkQ

$8),*+0'3+5 ,)*H/bG5)+0C5C*.78G & 2-,�78-45'0C*@27) & A?3c763KO ) & &92:*v*+09I+(+3@)L350'3+3,(KIE66&<*�)424IK--&O24AcG+--&)A &/3*)�7I)+2-0'3+3?79*@&79I+3@0C-4( )4&<-0/a>@(�3+O;79A(&93*).79- )+0 ) & &l7F)+)�7I2-3+A(&93*)�09>�3H/b3@)+&<A 3@&9,)(+*+2C)P/�763+O�3H(+*H68206978I�24-727)P/CQ $ & 79*@&<ONs¢D6&2/,<*M/bG5)40C59*.79G & / {�79-:3+0(,d79-:--&)Oe3+&/,<*@&/)Hs¢D6&2/ ,<*M/bG5)40C59*.79G & /9Y_763+Oe3H/bA?A(&/),*+27,2sPDI&)/L,)*H/bG5)4095C*.79G & /jp I.&[s,d78(+3+&) & &�3,79A &fD6&2/�243�(+3+&)OU>N0C*�&/3�,<*M/bG5)4270'3l763+OUO5&9,<*M/bG5)4270'3�� 2:3 & &)-4GK>@(+-bI+(5)�2-3�2C).3@&<-:>�3�06)T3H(��(,927&93*)>N0C*W76, & 2-&2682-3+5 ,/0'3��;O�&/3*)42=78--27)P/9Y 273 )+&<5C*@27)P/9Y�3+09A &UO5&/)4&/,/)+2-0'3 09>�O5&93�2479-43�09>�3+&)*H682-,/&9Y`763+O 273nG+*@&)6'&/3*)Hs2-3K5X6879*+270C(+3S>N0C*,Ac309>�,/0CAcG+(5)4&)*LA(243H(+3+&8Q���(KI+--27,2sPDI&)/ ,<*M/NG )40C5C*,79G & /n{�79-:3+0�,<79-4-7&<Ov783H/bA?A(&/),*+27,2sPDI&)/,<*M/bG5)40C59*.79G & /9YbI1&9,<79(+3@&'O�2:i.&<*@&93*)�D6&2/b3f78*+&�(+3@&<O���2:3TG;79*�)427,<(+-479*,-0/FB&)-4-+3H(�27)+&<OU>N0C*�D6&2/�Ag7I3;795'&)A &/3 ){¥DI&)/�7959*+&9&)A &/3*)dY;D6&2/aO�243�).*@24I+(5)+2-0'3;�2Y5273*)4&<59*+27)P/9Y;763+O�79( ) & &/3 )+2-,<7I)4270'3_Q� 3N>N0C*@),(�3;7I)+&<-:/9Y'&)66&93�) & &'I.&)3@) ,<*M/bG5)40C59*.79G & 2-,'79-:5'0C*@27) & A?3�,d7I3(08> )4&93�I1&),*+2:682479-4-0/�,90CAcG+*@0CA 2:3+&)O

>@*+09A 0C( ).3+2:O�&9Y�>@*@0CA B;2C) & 273_Y�763+O >@*@0CA I.&)--0rBY 2-3�7n6879*+27&/)P/ 09>oB�7d/b3<Q � -7) & 0C(+5 & 7e>N&)B B;24O�&)-:/G+(+IK--2-,/2 � &<O�, & 79-:--&/3+5'&<3 & 7r66&z*@&<3H(+-7)+&<O 2-3 &21 & 78(+3@)+2:6'&u3+&<79*+, & &<3 ) & *@0C(+5 & ) & &M&/3*)424*@&'D6&2/l3,G;76,/&X{�tJR $763+O�y�$ � 79*+& )PB�0(&21K79AcG+--&)3��2Y;A?763V/�,)*H/bG5)+0C5C*.78G & 2-,78-45'0C*@27) & A?3�0C* ) & &924* 2:A?GK--&<A(&93*).7I)4270'3+3 & 7r66&I1&9&93XI+*+09D6&93XB;27) & 0C(5)�*+&<3@0C*@)+2-3+5;)40M&21 & 78(+3@)+2-0'3_Q ¡ 0C*�&21K79AcG+--&8Y83M/N3�)4&)A?3�) & 7I)�&)A?G+-70r/D6&)/Vs¢*+&9,/0r6'&<*M/763+O�D6&2/VsA&<3@,<*@0�B )+&9, & 3524\E(�&<3 & 7d6'& 2-3*).*@2-3+3@2-, ),*.79G�O�080C*,3`763KOx79*@&�--2:D6&<-0/ )+0zI1&�3,(+Ib§@&/,/)�)40;,909A?G+*@0CA(243+&09> 063�&�>N09*,A 0C*z763�06) & &<*�p IV/K),*,(+3�)4&)O 2-3+3@24O�&)*,3)Y¤I+( )F79-:3+0cG.0I)4&93*)+2=79-:-:/vIV/K0C(5),3+2:O�&<*H3<Q �W79*HOKBL79*+&[s24AcG+-7&<A(&93*)4&)O(,)*H/bG5)+0C5C*.78G & / 2:3 09> )4&/3 ,/0'3+3+2:O�&<*@&<O()40�I.&uA 09*+&'3+&/,<(+*@&�) & 763g3@09> )PBL79*+&[sA24AcG+-7&<A(&93*)4&)O,<*M/bG5)40C59*.79G & /9Y�IK(5);) & 7I);2:3 3�06)M3�&/,9&<3H3.79*@24-0/�) & &<,<793+&8QW{ ¡ 0C* &21K79AcG+--&8Y+3+&/&v}�� � ��� Q �

]A3�763V/ &)66&93*)dY ,)*H/bG5)4095C*.79G & / 763+OD,)*H/bG5)+0C5C*.78G & 2-,?D6&2/N3�*@&<G+*@&<3@&93*)c763D2:A?G10C*@).763*) &21K79AcG+--&(09>) & &zG106)4&/3*)42=78- ,90'3�,/&93*).*,7I)4270'3(09> & 2:5 & s 6978-4(�& ).79*,5'&G).3 ) & 7F)f3 & 0C(+-:O?I1&uA 273�24A(2 � &<OUIV/ ) & & & 79*HOKBL79*+&[s3+08> )PB�79*@&XO5&<3+2:5'3jB & &<*@&)66&<*WG10C3H3+24IK--&9Q

%'& &ct 2 �(&[s ��&)-4-:Ag763k763+Ohy;2:66&<3@)Ms�$ & 79A 2:*Ms � O+-7&<A?763�{¥y $ � � 783H/bA?A(&/),*+27,2sPDI&)/�78-45'0C*@27) & A?3z79*@&&218),*+&<A(&<-0/J24AcG.09*@)�7I3 ) &[1K79A?GK--&<3 09>WG+(+I+-72-,[sPD6&2/�79-4560C*+2C) & Ac3<Q { ¡ 0C*lI;7I,�Db59*+0C(�3KO_Y'3+&/& $ , & 3�&927&<* ��3 ����� (� � =V� �D� �����#����� ���c}�� � /���Q����&)/�A?763;785'&<A(&93*)�G+*+&)3+&/3 ),3x3@0CA &�66&<*H/hO�2 �(,<(+-C)G+*+0CIK--&<Ac3<Q � 3 0'3�& &[1+78A?G+-7& 09>'7aO�&<3@24*,79I+--&

79G+GK*+0V76, & Y�) & &gt 2 �(&2s �M&<-:-4A?763nG+(+IK--2-,[sPDI&)/ )+&9, & 3�2:\E(�&�}��V��� G+*+0r6824O�&)3�763B&)--&<5C763*)XA(&d7I3+3J>N0C*JD6&2/795C*@&9&)A &/3 )$B;27) & 0C(5)�7W3 & 79*@&<OlG+*+20687I)4&fD6&)/�&)6'&)* & 7d682-3+5 )+0FI.&�).*.7I3+3,A(27)@)4&<O�Q � 59*+&9&)A &/3*) 243T*@&d76, & &<OB;27) & &d76, & G+79*@)P/e(+3+273+5�27),3 0rB;3�G+*+20687I)4&UDI&)/n763+O ) & &�06) & &<*FG;78*@)P/ �|3JGK(+I+--27,xDI&)/�{N0C* 273nAU(+-C)424DI&)/79-:5'0C*+2C) & Ac3<Y ) & &�06) & &<*FG+79*@)+2-&<3 �¤GK(+I+--27,xDI&)/b3��[Y I;793+&)OO0'3�G;79*�)42=78-�273K>N0C*HAg7I)+2-0'3�3 & 79*+&)O�79A 063+5 ) & &G;79*�)427&<3�>@*+09A B & 27, & &<76, & ,d763K,9063+3@),*,(�,G) ) & &O�&)3+24*@&<Oa3 & 79*+&)OkDI&)/v>N0C*'3H(+I+3@&<\E(�&93*)W3H/bA?A(&/),*+27,2sPDI&)/,909A?AU(53�2-,<7I)4270'3+3<Q

wFw

Page 131: Practical Architectures for Survivable Systems and Networks (Phase

� 3+-:/K) & *+0C(+5 & ,d79*@&)>@(+-�763KO ,90CAcG+*+& & &93K3+2:66&l3@).(KOK/ 09>�6b(+--35&<*.78I�24-727)427&<3u3,(�, & 793 ) & 0C3+& 3�0I)4&<OO273$ &/,/)4270'3 � Q:�a{N&9Q�5+Q0Y¤3@&9&a}��NY+/NY`� 3NY¤� � Y^� 39�bY�� � /��=�;2:3 2C)zG10C3H3+24IK--&<)40gO5&)6'&)--0CGn79-45'09*+27) & Ac3<Y;G+*@06)408,90C-:3<Y763+O 2:A?GK--&<A(&93*).7I)4270'3+3�) & 7F)�79*@&g3+2:5'3�2�� ,d763*),-:/h--&)3,3x6b(+-73�&<*,79I+--&()40�7F)+)�7I,�D�763KO�A 2:3,(+3@&9Q���&<* & 79G+3& &)*+&gA(0C*@& ) & 763 2-3"763V/O06) & &)*x78*+&d7K09>�3@&9,)(+*+2C)P/CY ) & &g(K-7)42:Ag7F)4&>),*,(5) & 243�) & 7I) ) & &)*+&?79*+&(3�0 &<793H/763+3MB&)*,3'B & &/3 2C) ,909A &)3 )40�) & &�3�0'3+3H(+IV6'&<*�)42:I�24-727)P/ 09>�,<*H/bG5)+0C5C*,79G & 27,J79G+G+-72-,<7I)4270'3+3<Q�{ $ &/&?}�� � �w��>N09*763L&218)+&93+3@2:6'&XO�&<IK(�3+D 2-3+5(09>�) & &Ax/ ) & ) & 7I);,<*M/bG5)40C59*.79G & /L2:3 2-3L27),3+&<-0>�7cG;7I3;76,9&<7KQ �

]A3 5'&935&<*.78- Y�) & &<*@&h79*+&�3@245'3�2�� ,d7I3 )L35&9&<OK3�>N0C* &/3+ONs )408s &93+O &935,<*H/bG5)+2-0'3 I1&/)PB�&9&93�,9080CG1&<*.7F)42-3K5&93*)+27)427&<3)Q ��0rB&26'&)*<Y ) & &)*+&jA?7r/�79-:3+0nI1&�3�&/&<O+3U>N0C*x79O+O�2C)4270'3;79-�--273+DO&93�,)*H/bG5)+2-0'3�79A(0'3+5 2-3*)4&)*+3;79-3�&G)PB0C*HD 350NO�&)3 )+0eG1&<*HA 2C)XGK*+0CG1&<* & 763+OK--2-3K5k7I3+O A(0'3�27)+0C*+273+5 09>3�&/)PB�0C*,DO).*,7 �(, & &d79O�&)*,3xB & 24--&G+*@06)4&/,/)4273+5�) & 7F);2-3K>N0C*HAg7F)42-063�2-3 ).*,763+3@27)dQ

� IK*+0V79O�*.763+56& 09>'3�)�763KO;79*,O�3HG.&/,92�� ,d7I)+2-0'3K3X>N0C*�G+(+I+-72-,[sPD6&2/B,)*H/bG5)+0C5C*.78G & /~} �r��/r� 243 ,<(K*,*+&/3*).-:/I1&92-3K5jO�& � 35&<O�(�3+O�&)*J]ZR�RSR 79(+3,G52-,9&)3<QX] )�&93�,/0CAcG;793,3@&<3G+(+IK--2-,[sPDI&)/ ,)*H/bG5)+0C5C*.78G & / ) & 7I)JO�&)G.&/3+O+30'3�O�243@,<*@&/)4&�--095V79*+2C) & Ac3<Y &)-4-724G5)+2-,�,)(+*H66&<3<Yo7I3+O�273*)4&<56&<*�>¥76,/)+0C*+2 � 7I)+2-0'3�Q�]A3H27),3lG+*+&)3+&93*)v79OK68763�,/&<OO+*,78> )f>N09*,A�Y*27)f79-4*@&d79ON/c79G+G1&d79*H3 )+0xI1&W763 &218).*,760C*HO�2-3;78*+24-0/U(+3@&)>@(+-�O�08,<(+A(&93*)<YK763KO ,909(+-4O?5'0x7�--0'3K5BL7r/ )+0rB�79*HOk(53�2:>�/82-3K5�) & &<,<*M/bG5)40C59*.79G & 2-,G+*+0bO+(�,G)uAg79*HD6&G).G+-476,9&8Q

%'& &�>@(5),(+*+& 09>�,<*M/bG5)40C59*.79G & 2-,�79G+GK--2-,<7I)4270'3+3�2:3j79-0B�7d/b3�7�-727)@).--&k(�3�,/&<*@).762-3�Q � -4560C*+2C) & Ac3c>N09*>¥76,G)40C*@2-3+5�-479*,5'&gG+*+2:A &vGK*+0bO+(�,/),3c763+OJ).*+27,�DE3U>N0C*�,90CAcG+(5)+2-3+5�O5243+,)*+&G)4&a--0C5C79*+2C) & Ac3xA?7d/D&<A(&<*H5'&9Qt 245627)�78-�3@245'3;7F).(+*@&<3Ag7d/eI.& ,909A?G+*@0CA(243.78I+--&UI1&)>N09*+&�) & &924*<273 )+&93+O5&<O &21NG�24*,7I)4270'3�O;7I)+&9Q %'& &c*+243HDE3AU(+3�)uI.&�,)--&d78*,-:/g*+&/,90C5'352 � &)O_Y+B;27) & 3H/b3@)+&<Ac3W763KOe79GKG+--27,d7I)+2-0'3+3fO�&<3@245'35&<On7I,9,909*,O�273+5C-:/9Q

� ������� � � - 1��'- � " - � ( � +�� � � � � -e1� �

� 3�&�09> ) & &�A 093@) 2:A?G10C*�)�763*)z3,(+I+3M/b3@)4&)A?3<) & 7I)�243�3�06)�&<793+2:-:/k7I)@)�76273;79I+-7&�)40bO;7d/ 2-3 ,/0CA?A(&<*@,92479-4-0/7d687624-479I+--&J3M/b3@)4&)A?3�273V6'0C-06'&<3W7g3+&G)�09> & 245 & -0/a3,(+*M682:6879I+-7& ),*,(+3�)PB0C*�) & /nO5243@),*+2:I+(5)4&)O�79(5) & &93*)+2-,d7F)42-063A(&9, & 7635243,Ac3>) & 7I)�,<763�3,(KG+G.09*@)c7k6879*@2-&/)P/ 09>u79( ) & &/3 )+2-,<7I)4270'3 G10C--27,92-&)3<Y�G+*+0r6824O�273+5 3�063+3,G10 08>¥79I+--&79(5) & &93*)+2-,d7F)42-063 O5&<3,G527)4& ) & &�G+*+&)3+&935,9& 09>xG106)+&93*)42479-4-0/ (�3*),*,(+3�)PB0C*�) & / ,90CAcG10'3�&93*),3vp 3H(�, & 783&93KONsP(+3@&<* )4&)*,A(2-3;79-:3T763KOcB�0C*,DE3�)�7I)+2-0'3+3)Y � &)I?3@&<*H66&<*H3<Y5273*)4&<*HA &)O�2=7F)4& 3�&G)PB09*,D 3�0bO�&<3)YN7I3+OlG.0C3H3+2:I+-:/5�7dB�&<O�&)AUI.&)O+O�273+5C3�09>�,)*H/bG5)+0C5C*.78G & 2-,S79-:5'0C*@27) & A?3)Q � &f7I)+)+&<AcG5)�)40M, & 79*,76,/)+&<*+2 � &S3+0CA(&S£f/ � 763*)+2-3�&[s--2:D6&o79( ) & &/3 )+2-,<7I)4270'3�3+&)*H6'&)*,3 ) & 7I) ,<763 0CG.&)*.7I)+&o3+&9,)(+*+&)-:/lO�&)3,G�2C)4&o3,(5, & (�3�,/&<*�)�76273 )+2-&)3<Yb763+O &21K79A(2-35&3+09A &�09>�) & &�A(0C*@&F*+&<79--2:3@)427,W6879*+24763*).3)Q %'& (K3<Y ) & &)*+&AU(+3�)oI.&AU(K-7)42:G+--&W79(5) & &93*)427,d7I)+2-0'3j3@&<*M6'&<*H3u>N09*& 2:5 & &<*z7d687624-479I�24-727)P/9Y52-3*)+&<*+3+79-`*+&<OK(�3+O;7635,)/�7I3+O ,)*+0C3H3MsA, & &9,�D 2-3+5j>N0C*u*+&)--2479I�24-727)P/9Y+763+O &218)4&/3+3+206'&�(+3@&09>;,)*H/bG5)4095C*.79G & /h>N0C*�,90'3��+O�&93*)42479--2C)P/CY 2-3*)4&)5C*+2C)P/CYT7I3+OD3�0'3K3,G10 09>¥78I�24-727)P/CQ � 3D24AcG.09*@)�7I3 )�G+*@0CG10C3.79->N0C*'7UGK(+I+--27,2s¢D6&)/ ,9&)*@)42�� ,d7F)4&2s¢I;793@&<O $ 24AcG+--&zt 243�).*@24I+(5)+&<OK$ &/,<(+*@27)P/g]A3K>@*.793�).*H(�,/),(+*+&?{ $Nt<$N]M�243�562:6'&/3IV/ y;2:66&<3�)l763+O �`79AcG+3@0'3 }��V�N�)��79--063+5�B;2C) & 7 $ &9,)(+*+&a��(+I+-72-, ��&)/"]A3K>@*.793�).*H(�,/),(+*+&h{ $K���]M�?}��9�8� Q$ &/&W79-:3+0 � I+79O�2 ��3�>N0C*,A?79-72 � 7F)42-063>09> $Kt<$N] ��3S-72-3+DI&<Oc--08,d79-53;79A(&u3HG;76,/&<3W}¦�<��Q %'& &)*+&�243�7--0'3+5 & 2:3@)+0C*H/09>TB�0C*HDK063e3H/b3�)4&<A(2-,x79(5) & &93*)427,d7I)+2-0'3�Y�560'2-3+5cI;76,�D )+0vm�&/&<O & 79A�7I3+O $ , & *+08&<O�&)*l}|�8�C�w�^I1&<5'273�3�2-3K52-3 �r��/8� {�B;27) & O�243@,90r6'&)*H/H09>X5;7rBo3)Y��K1 &<3)Yo763+O 0I) & &)*v79OK687635,9&<3?3+273�,9&L) & &/3�} �r� � Yf�C�8�w�=�2Y 0k] % ��3��&<*HI.&)*+0C3n}��C�bY��b�r�NYf�9�C�NYf�9� � �uI1&<5'273�3�2-3K5�79*@0C(�3+O �r�C��/bY'763+OH) & &et 245'2C)�79-Lt 243@),*+2:I+(5)4&)O $E/N3�)4&)A$ &/,<(+*@27)P/ � *+, & 2C)4&/,/).(K*+&a{¥tJt<$�$ � �X}¦�9�r�KY$�d��3��T79*+0C(53+O �r�C�9�KQ<$Kt<$N]u763KO $K���]u79*@&�763 0C( ).5C*@0�B ) &09><) & 7I)jG;79*�)427,<(+-479* , & 762-3 09><273 )+&<-:--&9,G).(;78- & 2:3@)+0C*H/ >@*+0CA ) & &e*+&<3@&d79*@, & ,/0CAcAU(�3�2C)P/CQE$ 0CA(&)B & 7F)2-3KO�&<G1&93+O5&93*)zB�0C*HDv3@)+&<Ac3o>@*@0CA ) & &�R�(K*+0CG1&d763aB�0C*,D�063K) & &�$KR $ � 0eR GK*+0w§@&/,/)x}|�#/9�w��Q

wFw �

Page 132: Practical Architectures for Survivable Systems and Networks (Phase

� ������� � � � � -e1 � � - � � � � 1 � ( � � " 1 � �:- 1 � ���r- �� 3c79IK3+0C-:(5)4&)-:/�,<*+2C)427,d79-bB&<79DU--273+D<) & 7I)TAU(+3@)�I1& 0r6'&)*+,909A &;243 ) & &o79IK3+&935,9&M09>¤763c79O�&<\E(;7F)4& ).*H(+3@)+&<OG;7I) & >@*+0CA ) & &'(+3@&<* )40�) & &�6879*+270C(+3�3H/b3�)4&<Ac3�I.&/2-3+5J(K3+&<O�YNG;78*@)427,<(+-479*,-0/<2-3lG1&<*,3@0'3;79-5,90CAcG+(5)+&<*,3�I+( )79-:3+0(2-3aB0C*HDE3@)�7F)42-063+3<Quy;&9,9&/3*)WB�0C*,D�7I);) & & � 352:6'&)*,3@27)P/L09>���&93�3K3H/b-:68763�247?IV/ � *HI;79(+5 & &/)W79- Q^} �r�8�I;793@&<O 063 ) & &924*;&<79*,-72-&<*'B�0C*,DL0'3L) & & � R � ]�$ $ &/,<(+*@&�£0806).3�).*,79G }��9�8�^G+*@&<3@&93*).3J7I3n79G+GK*+0V76, & ) & 7F)&93N>N0C*+,/&<3F7l3@).7I)427,�273*)4&<59*+27)P/vG+*+0CG1&<*�)P/L0'3 ) & & �;*,AxBL79*@&U763+Ok7 ,/0CAUI�273;7I)+2-0'3L09>�2-3+O+(5,/)4270'3_Y;O�2:5'27).79-3+2:5'3;7I),(+*+&)3<Yf763+O�A 0bO�2�� ,d7I)+2-0'3K3>)40 ) & &K,/0'3*).*@0C- ).*,763+3+2C)4270'3+3U>@*+09A ,9&)*@).762-3�A?7�§@0C*�A(0NO+(K--&<3x3,(�, &793 " #��� 763+O ��� � 2-3K3@).*H(�,/)+2-0'3K3<Q %'& 24379G+GK*+0V76, & 2:3�,d79-:--&<O = � � �� ������ � �A����� � ��� ��� �#�� �� � = ���������{ q � ]Mq'�[Q${ $ &9&�79-:3+0l*+&)-=7I)+&<OjB�0C*,D�063K),*,(+3�)PB0C*�) & /�79(5)+0CA?7I)4&)O�*@&9,/0�66&<*M/ }��N�2� Y+B & 27, & 3 & 79*@&<3uAg763V/09>�) & &3,79A &G+*@0CI+-7&<Ac3LB;27) & ) & &�).*,(K3@)4&)OkG+7I) & Q �

%'& &z-=76,�D 09>^763v79O�&<\E(;7F)4&�),*,(+3�)4&)OjG;7I) & 2-3 ) & &F*@&)6'&)*,3@&JO�24*@&9,/)+2-0'3�YE>@*@0CA 3H/b3@)+&<Ac3)40x(+3+&)*,3<Y+79-43@0*+&)G+*+&)3+&/3 ),3�7jB&<79D�--273+D 273"A?763V/�3H/b3�)4&<Ac3<Q � 3+&)*x78(5) & &/3*)42-,<7I)4270'3 243�2-3*)+&93+O�&)O )+0 &/3+3,(+*@& ) & 7I)X7G;79*�)427,<(+-479*�(+3@&<*;243o79( ) & &/3 )+2-,8Y;I+(5)uO�08&<3;3�06)u5C(;78*.763*)4&/&�) & &<2-3*)+&<5C*@27)P/�08> ) & &G;7I) & Q

qL--093+&<-0/�*+&)-=7I)+&<OJ)40+YL763+OH2-3�3+0CA(&a3+&/3+3+&e7h5'&/3�&<*,79--2 � 7I)+2-0'3J09>ZY ) & &K),*,(+3�)4&<ObsPG;7I) & G+*@0CI+-7&<A:2:3) & & 3�&/&<O >N0C*?793,3H(+*.7I3�,9& ) & 7I)v763V/ *@&<3@0C(+*+,/&�{¥O+7I)�7KYL3+0C(+*@,9& ,/0NO5&9Y 0CIb§@&/,/) ,90bO�&9Y �;*HAxB�78*+&9Yo7I3+O& 79*HOKBL79*+&d� & 793<3�06)�I.&/&93O)�79AcG1&<*+&)OhB;2C) & 0C*�06) & &<*MB;243@&g79-C)4&)*+&<O�Q %'& 243G+*@0CI+--&)A &[152:3@),3�B & &G) & &)*B�&L79*@&�,/0'3�,/&<*+35&<OxB;2C) & �;*,AxBL79*@&�273�-70 ,<79-V3H/b3�)4&<Ac3<Y83+&/3+3+2C)42:66&F{ ) & 7F)�2:3<Y�3,(+*M682:6879I�2:--27)P/Vs.Yr3+&9,)(+*+2C)P/Vs�Y609**+&)--2479I�24-727)P/VsP*@&<-7&)68763*)[� ,90CAcG10'3�&93*),3 08>!0CG1&<*,7I)4273+5J3H/b3@)+&<Ac3<YNA 2:O+O+--&2B�78*+&9YE78G+G+--27,d7I)+2-0'3x3+09> )PBL79*+&8YK7I3+Op 6'&<*M/�,)*+27)+2-,<79-4-0/�2-3 3�&/)PB�0C*HD6&<O � &<I�&/3V6 2:*+0'3KA &/3 ),3Sp 79G+G+-7&/).3�0C* 06) & &)*&[15&/,<(5).79I+-7&<3 ) & 7I),/0CA(&>@*+09A &[1 )+&<*@3;79-�3@0C(+*+,/&<3)Q %'& 2:3�*+&)3+0C(+*@,9&[sZ793H3,(+*,763�,9&aG+*@0CI+-7&<A 243U78-43+0n66&<*M/D24AcG10C*@).763*)>273�I;76,�DE(+G763+O�*@&/).*@2-&26978- Y 763KO 273�*+&9,/0'3��;59(+*.7I)+2-0'3�QUR�3,3@&93*)42479-4-0/�763V/ 0C( )HsA08>=sPI;763KO , & 763+5'&�)+0L) & &�3H/b3�)4&<A 09*3�&G)PB0C*HD�3�)�7I)+& 243X6b(+-73�&<*,79I+-7& )40 ,/0CAcG+*+0CA(243@&9Q � 0C*HDw79I+--&g79G+G+*@0V76, & &)3�Ag7d/"(+3+&a7 ,90CAUI52-3;7I)+2-0'309>JO5245'2C)�79-f3+24563;7I).(K*+&<3)Y ,<*M/NG )40C5C*,79G & 27, 273*)4&<59*+27)P/ G+*+06)+&9,G)42-063_YLO�&)O�2-,<7I)4&)O )�78A?G1&<*HG+*+0809> & 79*,ONB�79*@&{¥G+79*@)+2-,<(K-=79*H-:/c>N0C* ,<*M/NG )40C5C*,79G & 27,J>@(�3�,/)+2-0'3K3��2Y�G+*@0 08>=sA,d78*,*H/8273+5�,90bO�&9Y�7I3+O 06) & &<*'>N0C*HA?3 08>TOK/83;79A(2-,,90bO�&<, & &/,�D8273+5+Q� �����<� � � � 1 + 1�� 1�� �

� 2:6'&/3�79G+GK*+0CG+*@2=7I)+&L(+3@&<3 09> ,)*H/bG5)+0C5C*.78G & /a{ $8&9,/)+2-0'3�/NQ �NQ��C�[YC3H/b3�)4&<Ac3 ,d7I3�I.&fO�&<3@245'3�&)O�2-3xB & 2-, & �;-7&3+&)*H66&<*,3 3�&/&<OO3�06)JI1&�).*H(+3@)PB�0C*�) & /�B;27) & *+&<3HG.&/,/)�)+0 ,90'3��+O�&93*)42479--2C)P/ 09* 2-3*)4&)5C*+2C)P/CY 78-7) & 0C(+5 & ) & &<*@&B�0C(+-4Ok3@)+24-4- I1&x*@&<-72=79I�2:--2C)P/gG+*@0CI+-7&<Ac3z*@&<-=7F)42-3K5 )+0g5C(+79*.763*)+&9&<On7r68762:-=79I524--2C)P/v7I3+Oe3@&9,<(K*+27)P/kG+*@0CI+--&)A?3*+&)-=7I)+2-3+5 )40�G+*+&26'&93*)+2-3+5�O�&9352=79-:3 09>f3+&<*M682-,9&?763+OO&/3+3,(+*@2-3+5L) & 7I)�) & &c76,/,9&)3,3+&)O �;-7&�3+&)*H6'&)*,3x79*+&c79(Ns) & &93*)427,9Q %'& 2:3 243�).*H(�& &)66&93�B;27) & AU(+-7)+24-7&)6'&)-N3@&9,)(+*+2C)P/a{ &8Q|5KQ:Y+}��K�d�w�=�2Q��M0�B�&)66&<*)Yb562:6'&/3�) & &�G10C3H3+24I524--2C)P/09>¤7 �;-7&�3+&)*H6'&)*�I.&/2-3+5 ,/0CAcG+*+0CA(243@&<Ox>@*@0CA�B;27) & 2-3�0C*�>@*+0CA#I.&)--0rBY'2C) 243�(+3,(;78-4-:/XO�&)3+24*,79I+-7&)40 &/3+3,(K*+&) & 7I)�3+0CA(&?I+793+27, ),*,(+3�)PB09*@) & 2-3�&)3,3�2:3�GK*+0r6824O�&)O�IV/ ) & & �;--&l3@&<*H66&<*H3>) & &)A?3@&<-06'&<3)Y$G;78*@)427,<(+-479*,-0/k>N09*2-3*)+&<5C*@27)P/j7I3+OkGK*+&)66&93*)4270'3K09>$O5&93�2479-43 09>�3+&)*H682-,/&9Q� ������� � 1 + 1�� 1�� �� -C) & 09(+5 & 3;79A(&c3@&<*M6'&<*H3l79*+&k{@*.7I) & &<* 3;7�� 206'&<-0/K�<09> )+&93 ) & 0C(K5 & )>3�0I) )+0eI1&?3@&9,)(+*+2C)P/ ,)*+2C)42-,<79- Y!) & &)/79*@&�,9&<*�)�76273+-:/ ,<*@27)427,d79-�B;27) & *+&<3HG.&/,/)M)40lG+*@&)6'&/3*)42-3K5g76,/,92:O�&93*)�78-`763+OL2-3*)4&/3*)42-063;79-_O�&/3�2=78-43 09>�3+&)*H682-,/&763+O�)40 7I, & 2-&26 273+5D0r6'&)*.79-:-z3M/b3@)4&)A 763KO 3�&/)PB�0C*HD 3H(+*H682:6879I524--2C)P/CQ~]A3;7I,9,9&)3,3@24I�2:--27)P/H09>F3H/b3@)+&<A 7I3+O3�&G)PB0C*HD 3;79A(&�3+&)*H6'&)*,3�,d763 & 7d6'&cO�&269783@)�7F)42-3K5K&2i &/,/),3<Y�763+OO0C*,5C763�2 � &<Oh7I)@)�76,�DE3<0'3O) & 0C3@&l3+&<*M6'&)*,379*@&�G+79*@)+2-,<(K-=79*H-:/(3;793�)P/CQLq0C*,*@&9,/)+3�&<3H3 09>$O;7I).7 2:3o79-43@0c7c3@&<*+270C(+3oG+*@0CI+--&)AkQ�mz79A(&J3+&<*M6'&)*,3 ,<763k79-43@0

wFw �

Page 133: Practical Architectures for Survivable Systems and Networks (Phase

I1&�2-3+3�).*,(KA &/3 ).79- 273a7I)+).76,�DE3 ) & 7F)'(+3+&<273K>N&<*@&93�,/&<3 ) & 7I);,d763aI1&FO+*,7rB;3a>@*+09A�) & &�2-3K>N09*,A?7I)4270'3() & &)/G+*@0�682:O�&9Q� ����� � " � �� � 1�� �� & &/3K,/&<*�)�76273g>@(�3�,G)42-063;79--2C)P/ 243�3�06)'3H(��(,92-&/3*).-:/().*H(+3@)PB�0C*�) & /CY 2C)�A?7r/cI1&F(+3@&)>@(+- )+0�&93�,<79G+3H(+-=7I)+& 27)B;27) & 2-3e3+0CA(&U3+09*@)<09>�Bo*.78G+G.&)* ) & 7F)7I)+)+&<AcG5).3�)40 &93 & 763�,/& ) & &>),*,(+3�)PB0C*�) & 273�&<3H3�08> ) & &UBo*,79G+G1&<O,909A?G10'3�&/3 )<Q %'& 2:3 2:3^763�06) & &<*^Ag7I3�2:>N&)3@)�7F)42-063�09>5) & &3�0I)42-063 08>;5'&935&<*.78--2 � &<O�O�&<G1&93KO�&93�,/& ,9063+3+2:O�&<*@&<O2-3 $ &/,/)4270'3 �9Q��NQQ3NY 273 ),*H/82-3K5H)+0 A?79D6&"7 3@24-:D G+(+*H3+&B09(5)K09>�7�3+0rB �|3 &d79*)Q ��0rB�&)66&<*<YBo*.78G+G.&)*)4&/, & 3�0C-70C59/>243�79-0B�7d/b3�--24DI&<-0/�)+0�I1&o3,(+3@,9&)G5)42:I+--& )40<,/0CA?GK*+0CA(243@&L>@*+0CA#B;27) & 2-3l763KOl>@*@0CA�I1&<-70�BYE7I3+O2:> 3�06)SG1&<*H>N&/,/),-:/ 24AcG+-7&<A(&93*)4&)OcA?7d/c79-43@0XI1&u3,(+Ib§@&/,/)�)40>,/0CAcG+*+0CA(243@&�>@*+0CA 0C(5).3@24O�&8Q ¡ (+*@) & &<*HA 09*+&9Y) & &<*+& 243o3�).*+063+5 &26824O�&/3�,9& ) & 7I)u3,78>N&/)P/VsA,)*+2C)42-,<79- 763KOkA(243H3+2-063NsA,)*+27)+2-,<79-¤3M/b3@)4&)A?3�,d76353�06)uI.&X76, & 27&)66&<O) & *+0C(+5 & Bo*,79G+G�273+5!5�7dB&)Ojq'� % $l3M/b3@)4&)A?3W{@>N09* &21K79AcG+--&8YV3+&9&x} � / � YE�9�C�w�=�2Q ¡ 0C*T>@(K*@) & &<*�O�243@,<(+3H3+270'309>T7I)+)+&<AcG5).3;)40?(+3+&Uq'� % $�G+*+0bO+(�,G).3M2-3K,<*+2C)427,d79-`79GKG+--27,d7I)+2-0'3+3)Y+3+&/&�) & &XGK*+08,9&9&)O�2-3K5C3 09> ) & & � G+*@24-�9�C�9��£L*H(+3,3@&<-43vm � % � ,90'3N>N&<*+&/3�,9&�}|�C�8�8�M0'3 q0CAcA &)*+,/2=79-u�Wi�s %'& &[s�$ & &)-:>��*@0NO+(5,/).3 2-3 t &2>N&93�,/&� GKG+--27,d7I)+2-0'3+3)� %'& &�yo(5) & -7&<3H3z��(+*H3,(�2C)M09>�q'� % $¤Y�3H(+A?A?79*@2 � &)O 2-3 $ &/,/)4270'313NQ0�r�KQ|� 08> ) & 243o*+&)G.09*@)dQ� ������� �Q1S-0/ ( � $ � � ( - (�" (:� �� 3<3�0I)4&<O 2-3�3@&)66&<*.78-S3@&9,G)42-063+3<09>'q & 79G5)4&)*'3bY_B& 3�&/&<O�Ax(�, & I1&/)@)4&)*JG+*+06)+0 ,/0C-43zp A(0C*@&U*+0CIK(+3@)<YA(0C*+&J3@&9,<(K*+&9Y�A(0C*+& & 245 & -0/v7d68762:-=79I+-7&9YN763+O�3+0 0'3vp B;27) & OK*.79A?7I)427, 2:A?G+*@0r6'&<A(&93*),3M0r66&<*M&21 243�)42-3K50'3�&)3F{ % q��S�8]Z��6N�KYV> ).G_Y*)4&)--3�&G)dYE(+O+G�Yb3HA>).G;� ) & 7I)f79*@&u3@0C(�3+OK-:/�2:A?G+-7&<A(&93*)4&)O_QTy;0CI+(K3@) 3�&/)PB�0C*HD8273+5G+*@06)408,90C-:3zAx(+3@)78-43+0gI.&�&<AUI1&<O+O5&<OO2-3n3@0C(�3+O 09G.&)*.7I)+2-3+5?3H/b3@)+&<Ac3 � 06) & &<*MB;243+&8Y ) & &)/�78*+&>,/0CAcG+*+08sA(243+2:I+--&zp >@*+09A 0C(5).3@24O�&8Y;>@*+0CA B;27) & 2-3�Y�763+Oe>@*@0CA I.&)--0rBQ'] ) 2:3;,90'3�,/&9206978I+--&<) & 7F)W3@0CA &Bo*.78G+G.&)*)4&/, & 3�0C-70C59/ ,/0C(+-:OhGK*+0r6824O�&l3+09A &�3 & 0C*@)Ms )+&<*,A & &<-:G_Y`I+(5)5'206'&93O) & &cOK*.79A?7I)427,�2-35,<*+&<793+&)3<2-3�I;763+ObsB;24O ) & Y 27)�243�,)--&d78*>) & 7F) 24AcG+*+0r6'&)O�G+*+0I)408,90C-:3�79*+& 35&9&<O5&<O 763V/bBL7d/CQ %'& & 35&9&<OK3 09>u3H(+*H682:6879I524--2C)P/AU(+3�)uI.&JA(0C*+&7I,/)4206'&)-:/j*@&9,9095'3�2 � &<OK2-3 0'3K5'0'2-3K5c]ZR %o¡ 763+OL06) & &<*oG+*@06)408,90C- &)i.0C*@),3<Q� ������� �Q1S-0/ ( � $ + 1�� 1�� �

� 2:6'&/3j79G+GK*+0CG+*@2=7I)+&o(+3+&)3 09> ,<*M/bG5)40C59*.79G & /9Y53�&2B�35&/)PB�0C*,D?G+*+06)+0 ,/0C-43 0C*L793,3@24O+(50C(+30r66&<*,-47d/N30'3 ) & &&21 2:3@)4273+5uG+*+06)+0 ,/0C-43)Yw763+O ,d79*@&)>@(+- 24AcG+-7&<A(&93*)�7I)+2-0'3 0'3X*@&<-47I)4206'&<-0/F3@&9,<(K*+&LGK-=7I)H>N0C*,Ac3<Y 27)�2:3�2-3G+*+273�,92:G+--&G10C3,3@24I+-7&�)40�O5&)6'&)--0CGL3�&G)PB09*,Dg3@&<*M6'&<*H3Lp *+0C( )4&<*H3<Y+5C7I)4&2B�7d/b3<Y;5C(+79*,O+3)Y �;*@&)BL79-4-:3<Y��;-7)+&<*,3)Y;763+O 0I) & &)*2-3*)+&<*H>¥7I,9&xO5&)682-,/&<3up ) & 7I)�,d7I3�I.&x79O�&<\E(;7F)4&<-0/L).*,(K3@)PB�0C*@) & /9Q 0k(+-C)424-7&)66&<-`3+&/,<(+*@27)P/k*+&<\E(�2:*+&)3 &92C) & &)*&218),*.760C*HO�2-3+79*+2:-:/ ).*H(+3@)PB�0C*�) & /D0CG1&<*,7I)4273+5e3M/b3@)4&)A?3�063 B & 2-, & )+0nA 09(�3*)>) & &�3�&/)PB�0C*HD�3+&)*H66&<*,3)Y�09*&<-:3+&UAx(+-7)+24G+-7&X3@2-3+5C-7&2s¢--&)66&<-^3+&)*H6'&)*,3g{ &8Q|5+Q0Y�}��K�r�w���[QXmM&/)PB�0C*,De3+&<*M6'&)*,3AU(+3�)I.&UO5&<3+2:5'3�&)OO)+0jG+*+0r6824O5&,9063��;O�&/3 )+2=79-727)P/9Y�2-3*)4&)5C*+2C)P/CY+GK*+06)+&9,/)+2-0'3�795C762-3+3�)'O�&/3�2=79-:3 09>�3+&<*M682-,9&8Y�763+Oj>¥79(+-C) )40C-7&<*.7I3�,9&8Q� ������� � � � �%1 / #��� �k � � � ( � - 1�� �¡ 2:*+&)BL79-:-43�79*+& 2-3"3+0CA(&?3@&93+3@&a7k3HG.&/,92=78-�,<793+& 09>u7�Bo*,79G+G1&<*>273"B & 27, & ) & &�2-3*)4&/3*)>2:3�)40�Bo*.79G 763&93*)+24*+&<3�&G)PB09*,D�Q�]A3L) & 7I)M,<793+&8Y1) & & �;*+&2B�79-:- G.09--2-,2/�2:3;)P/bG�27,d79-:-:/ )40cG+*+&26'&93*)W3+&93K3+27)+2:66&<) & 2-3K5C3'>@*+0CA5'&G)+)4273+5 0C( )dYV763KO )+0FG+*@&)6'&/3*)fI+79O�) & 273+5C3$>@*@0CA#5'&/)@)42-3K5 2-3_Q$R$152:3@)+2-3+5 �+*+&)BL79-:-43�)+0NO;7d/ )4&/3+O�)40J3H(Ki &)*>@*+09A I1&92-3K5(273;79O�&)\E(;7I)4&)-:/g3+&9,)(+*+&8Y�7F)+)4&)A?G )42-3K5�)40 &93K>N09*+,9&G10C--27,927&<3) & 7I)u79*@&J(�3+3+09(�3+O_Y�763+O�I1&92-3K50CG1&<*,7I)4270'3;79-:-:/?A 2:3+,9063��;5C(+*@&<O_Q���0rB�&)6'&)*<Y.2-3aG+*+273�,92:G+--&8Y;7 �+*+&)BL79-:-!) & 7I)M2:3oB�&<-:-`O�&<3@245'3�&)On763KOkB�&<-4-

wFw �

Page 134: Practical Architectures for Survivable Systems and Networks (Phase

,9063��;5C(+*@&<Og763+OlB & 0C3+&zG.09--2-,/2-&)3�79*+&'B�&<-:-1,/0'3�,/&92:66&<O ,d763 2-3�>¥76,/)SI1& & 245 & -:/UI1&935& � ,/2=79-�Q %'& &uI.&)3@) 09>) & &�IK(�3�, & )40bO;7d/ 243'G+*@0CI;79IK-:/() & &�$ &/,<(+*@&Uq0CAcG+(5)+2-3+5cq09*,G10C*.7I)+2-0'3K$824O�&2B;2-3+O�&)*<YKB & 2-, & G.&)*,A(27).33@),*+0'3K5()P/bG�273+5�)40lI.&<273�,<-:(+O�&<OL273L) & & �;*+&2B�78-4- 3+&/,<(+*@27)P/jG10C-72-,)/9Q� 3N>N0C*@),(�3;7I)+&<-:/9Y!)40bO;7d/ �|3 �;*+&2B�78-4-43�763KO"*@0C(5)4&)*,3�79*@&c3@&<*@2-0C(+3H-:/n6b(+-73�&<*,79I+-7&�)40�O�&93�2479-0s 09>=sP3@&<*M6 27,9&

7I)@)�76,�DE3<Qcq063+3+&)\b(5&93*).-0/CY�27)�2:3�,<--&<79* ) & 7I)�763V/�3@&93+3@24I+-7&l79*+, & 2C)4&/,/).(K*+&lAU(+3�)�79O+O+*@&<3,3�) & &92:*J3,(+*M6 206Vs79I�2:--2C)P/c795V76273+3@)�79-4- ) & &J-724DI&<-:/ ) & *+&<7I).3)Q�]A3�GK*+2-35,924GK--&9Y �;*@&)BL79-4-:3�3 & 0C(+-4OjI1&J79IK--& )+0�3+&d78- 09i 2-3*)4&)*+3;79-3�&G)PB0C*HDE3v>@*+0CA 0C(5),3+2:O�&n7I)@)�76,�DI&<*H3<Q ]A3~G+*,76,/)+2-,9&8Y��;*+&2B�78-4-43g79*+&kG.09*+0C(+3)Q ]A3~G+*,76,/)+2-,/&9Y��;*@&)BL79-4-:379*@&K08> )4&93H,9063��;5C(+*@&<OJ)40"79-4-70rB�G106)+&93*)42479-4-0/"O5&)68793@).7I)4273+5 &2sPA?762:-�)40O&/3 )+&<*?763+OH&21 &9,)(5)�78I+--& � &<I,9063 )+&93*)�)40eI.&v*@&<\E(�&)3@)4&)O {�>N0C*>&[1K79A?GK--&9Y 0 2-,)*+0C3@09> )l� �(,9&a7I)@)�76, & A &/3 ),3<Y � 0C*,O 0k76,<*@0n6 2:*,(+3@&<3)Y� ,G)4206'& � Y � 7d687KY � 7d687*$ ,)*+2:G5)dYN763+Oa��0C3@) $ ,<*@24G5)��2Q�]A3jG+*,76,/)+2-,9&8Y 273*)4&<*@3;79-¤3H/b3@)+&<Ac3�O�&<G1&93KOK063�0C(5),3+24O5&>@(�3�,G)4270'3;79-727)P/CQ~]A3 G+*.76,G)427,9&9Y'O5&93�2479-43(09>J3@&<*H6827,9&n785V762-3K3@)() & & 0C(5).3@24O�&k*+0C( )4&<*H3v79*@&eG+*@0CI+-7&<A?7I)427,9Q¡ (+*@) & &<*HA 09*+&9Yb5'206'&93�) & &FG10C*+09(+3 3;7I),(+*+& 09> �;*+&2B�78-4-43)Y5273+3+2:O�&W*@0C(5)4&)*,3'78*+&F78-43+0X6N(K--3�&)*.79I+-7&9Q %'& 2:32:37�,d793@&�273jB & 2-, & G+*.7I,/)427,9&JO�08&<3;3�0I)zA?79DI&JG.&)*H>N&9,G)dQ

]PO�&<79-4-0/CY�3+&<*@2-0C(K3�G.&/&<*Ms )408s¢G.&/&<*�79( ) & &/3 )+2-,<7I)4270'3�763+O�I106) & &93KONs )+08sA&/3+O#763+O�--273+D &93�,)*H/bG5)4270'3) & *+0C(+5 & 0C(5)XA 2:5 & )I.& & &)-4GK>@(+- 273"*@&<O+(5,92-3K5e3+09A &(09>) & &cG+*+2:Ag79*M/n*@243,DE3 09>'O�&/3�2=78-0sA08>=sP3+&)*H682-,/&l7I)Hs)�7I,�Db3)Qf]A3�G+*,76,/)+2-,9&8Y�3�0(0'3�&3+&/&<Ac3'B;24-4-72-3+5 )40cG;7d/�) & & &/3+3,(52-3+5cG.&)*H>N0C*HAg7I3�,9&JG1&93;78-7)427&<3)Q

%'& & 063+-:/�3.7I3�&n3 & 0C*@)Ms )4&)*,A 3+09-4(5)+2-0'3 3+&9&)A?3 )40 I1& )40�3+&d78- 09i�2-3*)4&)*+3;78-�3�&G)PB09*,DE3v>@*+0CA ) & &]A3*)4&)*+3�&G)u68247U3@).*@2-3+56&93*) �;*+&2B�78-4-_G10C--27,927&<3�) & 7I)oI+-70 ,�Dg79-4-1) & *@&d7I)+&93�273+5�2-35,90CA(2-3+5�).*.7 � , ) & 7I)'A(245 & )78i.&9,G)K) & &O2-3*)4&)*+3;78- & 0C3@),3�763+O *+0C(5)+&<*H3<Q ]A3 ) & &�--0'3+5 )+&<*,A�Y 35&)B 79*@, & 27)+&9,G).(+*@&<3�763+O 3�&/)PB�0C*HDG+*@06)408,90C-:3o79*+&J(K*,5'&/3 ),-:/ 35&9&<O5&<O_Q

� ������� � � ( � �r- ( ��� � �

$ &/,/)4270'3�3NQ0� 3a3,(+5C56&<3@),3�) & & 3�&9&)O >N0C*x*@&d79-¦s )+24A(&l763;79-0/N3@243�09>'3H/b3�)4&<A 763+OD35&/)PB�0C*,D"I.& & 7d6 270C*U7I3+O79G+GK*+0CG+*@2=7I)+&()+24A(&<-0/�*+&<3HG.063+3+&)3<Q � 3�0'3�&�2:-4-:(+3@),*.7I)+2:6'& &[1+78A?G+-7& 08> & 0rB�) & 243XA 2:5 & )�I.&j7I, & 2-&26'&<O�YB�&�I1&<-72-&26'& ) & 7I);0C(+*&21 243�)42-3K5?R:0eR�y � �`t�{�RT6'&/3 )�0 063�27)+0C*+273+5�R 3;79I+-72-3+5UyM&)3,G10'3+3+&)3M)+0 � 3�09Ag7ws--09(+3�� 2:6'&lt 2:3@),(+*,I;7I3�,9&)3�� &93V6824*@0'3+A(&93*)g}¦�d�V�bY`�8�C�KY �C� � Y �C�43�� ,d7I3hI1&�*+&<79O�2:-:/k5'&93�&)*.79-72 � &<O )40�79ONsO+*@&<3,3uO�&G)4&9,G)4270'3_Y�763;78-:/b3+2:3<Y;763KOk*@&<3,G10'3+3@&�B;2C) & *+&)3,G1&9,G)�)+0?3@245'3�2�� ,d7I3 )oO5&<G;79*�).(+*@&<3o>@*+0CA &21NG1&9,/)+&<O3,(K*H682:6879I�2:--2C)P/Es¢*+&)--&)68763*) , & 79*,76,/)+&<*@243@)+2-,)3<Y5273�,<-:(+O�273+5X*@&<-72=79I�2:--2C)P/CYC>¥79(+-C)�)+0C--&)*.7635,9&9YN763+Ov7r68762:-=79I524--2C)P/�27379O+O527)4270'3<)40 ) & & ,<(K*,*+&/3*) &<AcG & 793@243 0'3U3+&/,<(+*@27)P/9Q %'& &�G+*@24A?79*H/�R:0eR�y � �`t~3@).7I)42:3@)427,d79- ,/0CA?G10'3�&/3*)*+&/,90C563�2 � &<3�763�0CA?79-70C(+3WO5&<G;79*�).(+*@&<3J>@*+09A &21NG1&9,G)4&<O 3�0C*HAg79-�I.& & 7d682-0C*)Y_B & &<*@&d793�) & &?R:0eR�y � �`t3+2:5'3;7I),(+*+&[sPI;783+&<O ,/0CAcG.0'35&93*)�243W*,(+-7&xI;793@&<Oh763+O�*@&9,9095'3�2 � &<3 ) & &�G+*@&<3+&/3�,9& 09>�G106)+&93*)42479-�&[1KGK--0'2C)�7ws)4270'3+3;09>$D8350�B;3 0C*o3,(+3HG.&/,/)+&<On6b(+--35&<*.78I�24-727)427&<3)Q�]A3e79OKO�27)+2-0'3_Y+7(3�&2B & /bI+*+2:On£�7d/'&)3+24763 ,/0CA?G10'3�&/3*))�78D6&<3(0'3�3+0CA(&L09> ) & &�79OK68763*)�785'&<3(09>FI106) & Q %'& &eR:0eR�y � �`t�*@&<3+09-:6'&)*?G+793,3@&<3 ) & &�*+&)3,(+-C).3 09>) & &�763;79-0/ )42-, &93K5'2-3�&)3 0'3 )+0j7v*+&)3,G10'3+3+&�,/0 09*,O�273;7I)409*U{@(�3+O�&)*FO�&)66&<-70CG+A(&93*)[�F763KO )40 & 2:5 & &)*MsP-47d/'&<*2-3K3@)�7I3�,9&)309>_R 0kRSy � �`t *H(�3�3�273+5B;27) & 5C*@&d7I)+&<*S3+,909G.&�09> 7dBL79*+&/3�&<3H3<Q � 0C*HD�243_§H(+3�)LI1&<5'273�3�273+5<0'37j*+&)3,G10'3+3+& ,/0 0C*HO�2-3+7I)40C*�) & 7I)JB;2:-4-�G+*+0r6824O�&�3HG.&/,92�� ,l*+&d78-0s )+24A(&x78OK682-,9&�>N0C*WO�&)>N&/3+3+206'&?76,/)+2-0'3+37I3+O06) & &<*T*@&<A(&<O�247I)4270'3_Q � 27) & 0'3+-0/X3H--2:5 & ) &218)+&93+3@2-0'3+3)YE7F5'&935&<*.78--2 � &<O�R:0eR�y � �`t ,90C(+-:O�79-:3+0FA(&<O�247I)4&,9063.5 2-,G).3 ) & 7I)oA 2:5 & )o79*@243+&�79A(0'3+5�) & &O�2:i.&<*@&93*)u3,(+I )4&93KO�&<Ok3,(+*M6 206879I�24-727)P/?*+&)\b(524*+&)A &/3*).3<Q

R:0eR�y � �`t 243u7I)zG+*+&)3+&/3 ) 0C*+27&93*)4&)OeG+*@24A?79*+2:-:/()40rBL79*,OnO5&/)4&/,/)+2-0'3_Y�763+79-:/b3+2:3<Y�763+Ok*+&)3,G10'3+3+&X*+&[s-=7F)4&<O"3,G1&9,/2�� ,<79-4-0/ )40e3@&9,)(+*+2C)P/"A(243H(+3+& 09> ,/0CA?GK(5)4&)*�3�&G)PB09*,DE3<Qn] ),3xI;783+2-,?79*@, & 27)+&9,/),(+*+& 0CI+3+&)*H66&<35'080NO�3@09> )PB�78*+&(&93+5'273�&9&)*+273+5aG+*.76,G)427,9&9Y�79I+3�).*,76,/)+2-0'3_Y^763KO 273 )+&<*@3;79- 2-3*)+&<*+09G.&)*.79I�2:--2C)P/CY 763KO 2:3�3;7I).(bs*.78-4-:/hB�&<-4-o3H(�27)+&<OJ)40O) & 2:3�5'&93�&)*.79-72 � 7I)4270'3 &)i.0C*@)Up B & 27, & B�&kI1&<-72-&26'&jB;24-:-��;-4-�7hA?7�§@0C*�5V78G�2737I)@)�76273�2-3+5�5 &[1 24I+-7&X3M/N3�)4&)A�79*@, & 27)+&9,G).(+*@&<3W>N0C*o3H(+*H682:6879I524--2C)P/CQ'R:0eR�y � �`t 243z79-:3+0cG;79*@)+2-,/24G;7I)+2-3+5 273

wFw �

Page 135: Practical Architectures for Survivable Systems and Networks (Phase

) & &�q0CAcA 063e]A3*).*H(+3+270'3�t &/)+&9,G)42-063 ¡ *.79A(&)B�0C*,Dh{�qL]Zt ¡ �M&2i 09*@)dY�B & 27, & B;24-4- &/3;79I+-7&>,/0'3+3+2:O�&<*,79I+-7&2-3*)+&<*+09G.&)*.79I�2:--2C)P/e78A 0'3K5jO�2:i.&<*@&93*)X763;79-0/N3@243F3M/b3@)4&)A?3X763+Oh*+&)(+3.78I�24-727)P/ 09>273+O�206 2:O+(;79-�,909A?G10'3�&/3 ),32-3B06) & &)*�&93V6824*@0'3+A(&93*).3)Q�]A3�79O+O�2C)4270'3 )+0�3+&9,)(+*+2C)P/VsP*+&)-=7I)+&<O�79GKG+--27,d7I)+2-0'3+3)Y^B�&a79*@&�,90'3*)+&<AcG+-=7I)+2-3+52-3*)+&<5C*,7I)4273+5vR:0eR�y � �`t B;27) & 7 ,<-4793,3@2-,<79- 35&/)PB�0C*,DkAg763+795'&<A(&93*)z>¥76,92:--27)P/9Y;B & 2-, & B�0C(+-:O�G+*+0r6824O5&*+&<79-0s )42:A & 273K>N0C*,A?7I)+2-0'3J*@&<-=7F)42-3K5M)+0 ,9063��;5C(+*,7I)4270'3�Ag763+795'&<A(&93*)<Y9G1&<*H>N09*,A?763�,9&SA?763;795'&)A &/3*)dY�>¥79(+-7)A?763;795'&)A &/3*)dY+3@&9,<(K*+27)P/vAg763+795'&<A(&93*)<Y;763+Ok76,9,/0C(�3*)4273+5lAg7I3;795'&)A &/3 )<Q

� &�*@&)>N&)* )+0hR 0kRSy � �`t & &<*@&�GK*+24A?79*@24-:/O)+0 2:-4-:(+3@),*.7I)+& ) & &aG106)4&/3*)42=78-'79G+G+-72-,<79I�24-727)P/O09>z*+&<79-0s)42:A &'A(0'3�2C)40C*@2-3+57I3+Ov763+79-:/b3+2:3 2-3 ) & &uAg76273*)4&93+763�,9&;09>_3,(+*M6 206879I+--&o3M/N3�)4&)A?3)QfR:0eR�y � �`t & 783�) & &0C-:O�&<3�)�7635,9&<3�).*M/v763KO ) & &u5C*@&d7I)+&<3@)L5'&935&<*.78--27)P/ 08>`79G+G+*@0V76, & {�>N0C-4-70rB;2-3+5�2C).3SG+*+&)O�&9,/&<3,3@0C*,3']ZtJR $g7I3+Omz]ZtJR $+�[Q�{ $ &/& & )+),G_���9�wB'B'BQ ,)3,-�Q|3H*+2 Q ,909Av�I273*).*,(K3+2-063_Q & ),A?-_>N0C*;&[1 )+&93+3@2:66&UI;76,�DE5C*@0C(�3+O 063 0C(K*uB�0C*,D2-3L) & 243o79*@&d7KQ �?] ) & 793z79-43@0 & 79O ,/0'3+3@24O�&)*.79I+-7&<&<AcG & 793@243oO�&)6606)4&)O )+0 2C).3o3+09> )PBL79*@&�&/3+5'2-35&9&<*@2-3+5KQ��W>G;79*�)427,<(+-479*�*+&)--&2697I3�,9& & &)*+& 243'7a�r�C�9�UG;79G1&<* &93*)+27).-7&<O � �6������ (���+��� � �� � ����� ?� � � ��� � � �*�F}��9�C�8�{ & )@).G_� �C�wB'B'BQ ,<3H- Q�3,*+2�Q ,/0CAg�I3�&<(KAg76353��8O�&G)��C�KQ & ).Ac-`763+O{ & )@).G_� �C�wB'B'BQ ,<3H- Q�3,*+2�Q ,/0CAg�I3�&<(KAg76353��8O�&G)��C�KQ�G+3)Q%'& &�*+&)\E(�24*@&<A(&93*).3`>N0C*`A 063�27)+0C*+273+5�AU(+3�)�79-43@0uI1& ,90'3K3+24O5&<*+&)O>,<79*+&2>@(+-4-0/CYw793 B�783�O�063�& 2-3�) & &u�r�C�43

O�08,<(+A(&93*)W}��C�w� ) & 7I) &<3�)�79IK--243 & &<O ) & &'3+&9,)(+*+2C)P/l*+&)\b(524*+&)A &/3*).3�>N0C*�]ZtJR $ 2:A?GK--&<A(&93*).7I)4270'3+3<Q � A 0'3K53+&/,<(+*@27)P/�35&9&<OK3<Y93H(�, & 7'3M/N3�)4&)A AU(+3@)`I1&�79I+-7& )40;&<3�)�79IK--243 & 7'3@).*@0'3+5o*+&)3+2:3@)�7I3�,9& )40u7I)@)�76,�D�{ 2-35,<-4(KO�2-3+53,G1080�� 3+5 763+O O�&9352=79-:3K08>U3+&)*H682-,/&r�a763+O AU(+3�)eG+*@06)4&/,/)L) & &"3@&93+3@27)4206827)P/ 09>�) & &"79(+O527)aO;7I).7 7I3+OO�&)*+2:66&<O 273K>N0C*,A?7I)+2-0'3_Q$� ) & &)*L*@&<\E(�24*@&<A(&93*).32-3�,)-4(+O�&z5'&935&<*.78--27)P/(09> 79G+G+*@0V76, & 763+Ov79G+G+-72-,d78I�24-727)P/>)+03�&2B O50CAg7I2-3+3)Yb3@,d79-479I�2:--27)P/9Y�5 &21 24I524--2C)P/CYE79O+79G5)�78I�24-727)P/CYE*@&<(+3,79I�24-727)P/ 09>!,90CAcG.063�&93*).3)Y5273 )+&<*@0CG.&)*.79I524--2C)P/B;27) & 06) & &<*f3H/b3@)+&<Ac3<Y;763KO�) & &J78I�24-727)P/�)+0�0CG1&<*.7F)4&F7F)�O�20i &)*+2-3K5X-7&)6'&)-43 08>^79I+3@),*.76,G)4270'3 09>^78(+O�27)fO;7I).7763+OX*+&)3,(+-C).3<Q $ &9&F}|�8�C�w�b>N0C*^7zO�2:3+,)(+3,3@2-0'3�09>�) & &�2:A?G10C*@).763�,/& 08>+5'080NO�3+08> )PB�79*@&2s &93+5'273�&9&)*+273+5WG+*,76,/)+2-,/&2-3 ) & &O�&)66&<--09G+A &/3*)�08>$A(0'3�2C)40C*@2-3+5�7I3+Oe7I3;79-:/b3@243�3M/N3�)4&)A?3)Q

� ��������� � � "F �r- 1 " - � � � � J #��� 1�� � 1 �

� 27) & *@&)>N&<*@&93�,/&�)40K) & &v3M/b3@)4&)A 27, 273;79O�&)\b(+76,927&<3>09(5).-72-3�&)OB2-3 q & 79G5)+&<* � Y % 78I+--& /NQ0�v3,(+AcA?79*+2 � &<33+09A &O09>�) & &hAg7r§@0C* & (+*,O+-7&<3L) & 7F)kAx(+3@)�I1&�79OKO+*+&)3,3+&)O >N0C*L&d7I, & ,909A?G10'3�&/3 )K09>�) & &�G+*@&)682-09(+33,(KI+3+&/,/)4270'3+3)Q %'& &�).79I+-7&�,/0'3+3+2:O�&<*H3 ) & &>2-3*)+&<5C*@27)P/CY1,9063��;O�&/3 )+2=79-727)P/9Y¤7d68762:-=79I�2:--2C)P/CY+7I3+On*+&)--2479I�24-727)P/ 09>6879*+270C(+3u>@(�3�,/)+2-0'3+79- &/3*)427)+2-&)3<Y 793 24-4-:(+3@),*.7I)+2:66& 08> ) & &�, & 78-4--&/3+5'&)3<QJ] )J3H(+5C5'&)3@).3 ) & 7I)FB�&�3@)+24-:- & 7r66&l7--063+5UB�7d/ )+0c560+Q

]A3c--245 & ) 08> ) & &M&[18)4&93K3+2:66&F3+&G)08>_--2:A 2C)�7I)+2-0'3K3 273 ) & &uG+*+&)3+&93*)�)4&9, & 3�0C--0959/ &21 & 2:I�27)+&<O(2-3 % 78I+--& /NQ0�{�7I3+O ) & & ).79I+--&k5'2:66&<3 0'3K-:/ 7�3,79AcG+--273+5E�2Y�B�&�*+&/27)+&<*.7F)4& ) & 7I)a3,(K*H682:6879I�2:--2C)P/�763+O 27),3v3,(+I )4&93KO�&<O*+&)\E(�24*@&<A(&93*).3�09>u3@&9,<(K*+27)P/�763+O�*+&)--2=78I�24-727)P/�79*@&g>@(�3+O+79A &/3*)�79-:-:/�B&<79DCsP-72-3+D"G+*+0CIK--&<Ac3<Q %'& & ).79I+--&6'&)*H/?3+2:A?G+-0/ ,90'3V66&)/b3 ) & &zA &)3,3.785'&�) & 7I)LB�&d78D?-72-3+DE3�78I.0C(53+O_Q � -7) & 0C(+5 & B& )+&93+O�)+0U3+&/&<D ��� � ���.��� �� ����� ��� �_B�&x3+&/&<A )40?76, & 27&)66&�0'3K-:/ � � �O� �+����� �� ����� ��� � %'& &x*@&d79- , & 79-4-7&93+5'&<2:3;)+0 0r66&<*+,/0CA(&�) & &--2:A 2C)�7I)+2-0'3K3S3H(+5C5'&)3@)+&<OeIV/ % 79I+-7& /NQ:�9Q

� ������� � � � 1�� - � ( � � � � � � 1�� � 1 �$N(+*M682:6879I�2:--27)P/L,)--&<79*,-0/aO�&<G1&93+OK3 063nAg7I3E/kG1&90CG+-7&xO+(K*+2-3K5 ) & &xO�&)66&<--09G+A &/3*)�,)/8,<-7&9Q ��0rB�&)66&<*<Y�0'35&09> ) & &u-479*,56&<3@) ,90C-:--&9,G)4270'3�09>�B�&d79DU-72-3+DE3�7I3+O�6N(K--3�&)*.79I�2:--2C)42-&)3 &)A &)*,5'&)3 0'3+-:/XO+(+*@2-3+5 ) & & 0CG1&<*,7I)4270'3;79-G & 783+&9YEB & &)*+&u3,(+*M6 206879I�24-727)P/XO�&<G1&93KO+3�063(09G.&)*.7I)+0C*,3)YN78O+A 273�243�).*,7I)40C*H3<YV7I3+Ol(+3+&)*,3<Q � 3 3506)4&)Og79I10r6'&8Y79O+A(2-35243@),*.7I)+2-0'3 09>�,<*M/NG )40C5C*,79G & /aG+*@&<3+&/3*).3M&93�0C*HA 09(+3'*+2:3,DE3<Q � &*+&<A(2-3KO 0C(+*'*+&<79O�&)*,3;0'3�,/&795V76273

wFw �

Page 136: Practical Architectures for Survivable Systems and Networks (Phase

��������� � w�� ����������������������������� ��!��"����#���$%���"������&�'�()+*�,.-�/�0213,�4�5202/"6 78,9/�:;=<>0?/�6 @A13,.B�C�:,9/�024�520?/�6 DFE�4�025G4IH�0G5202/"6 JF:5G024IHK025G0?/�6���������L�M�>�"��&N' OP'����������Q�R�F��& OP'����������Q�R�S�"& OP'������������R�S��& OP'������������R�T��&(U&�VW�RXY����� �������F&�'Z��&>XY�M� �������T&N'[��&>XY�M� �"�M���T&�'\��&>X���� �"�M���T&�'Z��&>X����

���]�N�M��(M^�L����_T&�V ���]�N�M��(M^�L����_S&�V �L�]�����"(�^N�L����_F&�V �L�]���M��(�^��L����_F&�V�8&N���"���8��'���(�( �8&��"�"��� �"'���("( �M&��"����� ��'���("( �8&N���"���8��'���(�(

`a(��M�b���L�>��V?&��"$c(�d ef����_\(U���8!��"�Q�R�Nd ef����_F(����M!������R��d gh��'�T�8����(�����(�d i�ekj�lem lI(MdI$c�Ln�nI���MXo���"��d ��(��=���8�L�������FXb���M' ��(��=���8�L�������TXb���M' p����q�M�"��&N�"(�d �"�M���������������R�����&>X�(��M��(�dN�M�"�� '��8�RXY&��"_���nr^ '��8�RXY&��"_���n !���s�����nI�tX�&��( &�VW�"�M'Z�3&�&N�

m l\(U�3&&�V2�������u��8�RXY&��"_��'�s v����]XY��n\nI��(���s�'�( v.�L�]XY��n\nI��(���sN'�( ew����_T���"&���&I�M&��L(Md ew����_[���"&���&I�M&��L(Md��'�n[���"&���&I�M&��L( ��'�nZ�M&n�� ��'�n\�8&InI� �M&n��t��!�sN( �8&InI�x��!�sN(y ����I�"&�s���������� zK&&��o�M${�=��n�nI��'�s�d zK&�&N�o�M$A�3��n�nI��'�s�d gh�N(�(Y$S���"_��M� l!���|R��� �b�"&S�����} V?&��b��'�����s��"�Q�R�Nd �8&N$%����&N$%�L(��~V?�"&�$ _��M�F�8�I�=&�(U!�����(Md ����'�nI������nF�� �M�"�"&���(Md_������!I�"���M'����L�M������&�'�d Xb�Q�"����'3j]�3�M��&>Xx^ ������N(�(���(�^ sN&>���M�"'�$c�M'�� !�'��]�>�����L���������Q�R�Nd�M'��M����I�"��&N'=� s�&>�9� �o�3&����L�8����( s�&>�9� �b�3&������M����( �M����I�"&{�3&������M����( (���'=���[���"&�������$c(��!I�"���M'����L�M������&�' �b�M���L��'��M�x&�' �b�M������'��8�q&N' �a'\&N!I�"��s��q�M��' OP'��M&�'�(���(U����'��8�(U!��=(U�I(U���M$S( p��I��n\�"�M!�("������� p��I��n\����!�("������� (��!I��nI&>Xb'\����� ��$c&N'�sc$A!������������

����("(�X�&N�"n�( ����("(UXY&���n�( nI���=��'�nI��'N��!=(U���"( ��!�������'N�"�����>�"&���(�+�"!�(U����n[��������( �t�M'����"������� �t�M'����"������� �~�M'��L���L(o&�V �t�M'��M�����������'�n[����(U&N!����8� '�&�'��8�I��(U����'�� '�&�'��M�I��(U����'N� (��M�"����M� '�&N'��8�I�L(R�"�M'����'�����s��"�Q�R� &��b�N�M�"�TX�����_ &��b�������SXY����_ ���"&�������$c�����L� &��b�N�M�"�SX�����_l�M�"�����"( } p=���Nd ef����_\(U���8!��"�Q�R�9^ ef����_F(����M!������R�9^ m !I����sN��(o��'�n i�ekj�leVW����d���������d ���N��_��'�sS�M����I�"&�d ���N��_���'�sc�8�"��I��&=d (��M�"����M�tnI��'��L���L(Md �"�M���������������R��8��$c�����W� ��!I�"���M'��"�����>����&�' ��!I�"���M'����L�M������&�' ��'��8&N$c���>�"���������Q�"����( &�VW�"�M'Z�3&�&N�ef�������3�M��( y &�$c���"&�$c�L(U�tV?�"&�$ y ��'�'�&��b����'=nI�M� l������L�8�qnI�M'�������( g�!�����nI���=��'�n�(

�=����&>X~j>Xb�Q�"����'�d ��'�(��LnI�M��( &N'[Xb�������3�M��( &�'ZXb�������3�M��M�N�M'Z&�!I��(U�LnI� $S�]�S�3�x����(�� �"�M���������������R�

v.���"�MXo������( y &�$c���"&�$c�L(U�tV?�"&�$ ef����_T�3&������M����(Md l������L�8�qnI�M'�������( u�&N'��"�M���������>�"��&N'�=����&>X~j>Xb�Q�"����'�d X�����_F(����M!������R� &N'Fp��"�MXo�����L( ������n�(Y��&T(��M�"���L�8��M�N�M'Z&�!I��(U�LnI� $S�]�S�3�x����(�� &�!��"��sN��(

g�&�'�����&N����'�s=d �Y���=��("(��������Nd l�M'�(���������� ua&��b��&N��!�(U��d ����s�&N��������$c(��'������I(���(�d ���������"�������Nd n��>���{$S�]�T�3� (�!��I|R��� �o��& �R����L�M�����������(U�3&�'�(�� (U�3&&�V2������� �8�I�=&�(U��n (��M�"����M�tnI��'��L���L( ��'��8&N$%�����M���

wFw �

Page 137: Practical Architectures for Survivable Systems and Networks (Phase

) & 7I)c79-7) & 0C(+5 & ) & &aAg7I2-3 &<AcG & 783+243�08>�) & 243l*+&)G.09*@) 243�063 79*@, & 27)+&9,G).(+*@&<3<Y ) & &aI1&<3�)g78*+, & 2C)4&9,G).(+*@&09>u79-:-�Ag7d/�I1&�,90CAcG+*@0CA 2:3+2:I+--&�20> 27)XO�08&<3�3506)UG+*@0CG1&<*,-0/h79O+O+*@&<3H3�) & & 0CG.&)*.7I)+2-0'3+79-S793,G1&9,G).3<Q %'& &79G+GK*+0V76, & 09> ) & 2:3J*+&)G.0C*�)3@),*+&<3H3+&)3�) & &�24AcG.0C*�)�7635,9&�09>L7�)406).79-0s¢3H/b3@)+&<A 09*+2-&/3*)�7I)+2-0'3_Y¤B;27) & *@&<3,G1&9,G))40 ) & &�&93*)42:*+&>&/3*)4&<*HG+*+2:3+&�783F7g3M/N3�)4&)A 09>�3M/b3@)4&)A?3)Y 7 35&/)PB�0C*,D 09> 3�&G)PB0C*HDE3<Y`763+Ok6 27&)Bo3 35&/)PB�0C*,DE37933H/b3�)4&<Ac3<Q %'& 243�79G+G+*@0V76, & *+&9,/0C5'3�2 � &)3 ) & & ,<*+2C)427,d79-TO5&<G1&93+O�&/3�,9& 0'3"A?763V/�G1&90CGK--&9Y�&)66&93�B & &93) & &X78*+, & 2C)4&9,G).(+*@&<243'3,G1&9,/2�� ,<79-4-0/vO�&)3+2:5'3�&<OL)40�)+0C--&)*.7I)+& & (KAg763a>N0'2:I+--&)3<Q

��� � � � � ��� ��� � � ��� � � � ��� 5� �� � ��� � � � � � � � �

� 3+2:5'3�2���,d763*)G;79*,79O�2:5CA >N09* ,/0'3*).*@0C-4-7&<O &21 &/,<(5)+2-0'3 2-3V6'0C-06'&)3<) & &l(+3+&(09>fA 09I�24-7&�,90bO�&xp ) & 7F)<243<Y,90bO�& ) & 7I) ,d763�I1& &21 &9,)(5)4&)O 2-3KO�&<G1&93+O5&93*).-0/ 09>uB & &<*@&K2C)�243�3�)40C*@&<O_Q ^ %'& &kA(0C3�)�,90CAcA(0'3 ,d793@&2-3V660C-:66&<3'G10C*@).79I+--&u*+&)(+3.78I+--&�,/0NO�&F76,<\E(�2:*+&<Ov>@*@0CA 3+0CA(&FG;78*@)427,<(+-479*S3+0C(+*@,9&)3�{¥*+&)A 0I)4& 0C*f--08,d79-=�S7I3+O&21 &/,<(5)+&<Oc--08,d79-:-:/CQ ¡ *@0CA 7zO�2:i.&<*@&93*)�G1&<*,3HG.&/,/)+2:6'&8Y 27) ,/0C(+-:O�2-3V6'09-:6'&'-70 ,<79- ,90bO�& &[15&/,<(5)+&<O(&<-:3+&)B & &<*+&8Y0C*X*+&<A(06)+& ,90bO�&�&[1 &9,<( )4&<O 7I)U763�06) & &<*U*@&<A(06)4&?3+2C)4&9Qe]PO�&d79-:-:/9YTA 09I�24-7&(,/0NO5&v3 & 09(+-4O I1&vG+-47I),>N09*,A2-3KO�&<G1&93+O5&93*)dY�7I3+OB,<79G;79I+-7& 09>'*,(53�3�2-3K5e763V/EB & &)*+&�2:*,*+&)3,G1&9,G)42:66& 08> & 0rB 763+Oh>@*+0CA B & &<*+& 27)BL7930CI5).762-35&<O_Q � 3+&<OK2-3 ,/0'3�3�&/,/)+2-0'3jB;27) & ) & &JG+*@2-3�,/24G+-7&<3 08>$3@&<G;79*,7I)4270'3 09>�O�0CA?762-3K3'763+O�79-:--08,d7I)+2-0'3(09>--&<793@)XG+*@2:6824-7&<5'&8Y^ON/ 3+79A 27,?-72-3+D 273+5+Y^763+O"OK/83;79A(2-,l--0V78O�2-3+5aB;27) & G1&<*H3+2:3@)4&/3*)l76,9,/&<3H3�,90'3*),*+0C-:3<Y�) & 2:3G;79*,79O�2:5CA G+*+0r6824O�&)3u763 0CG+G10C*@),(�3�2C)P/?>N0C*�) & &J3@&9,<(K*+&<&21 &9,)(5)4270'3L09>^A 09I�24-7&�,/0NO�&8Y;763+Oj*@&<G+*@&<3@&93*).3z76'&)*H/aG+*@0CA(243+273+5�79GKG+*+0V7I, & >N0C*o7I, & 2-&26 273+5c(+-7),*.793H(+*H682:6879IK--&F3M/N3�)4&)A?3)Q

�W>!,/0C(+*,3@&9YE/'0C( ,d763 & 7d6'&uAg7r§@0C* 2-3*)4&)5C*+2C)P/CY*,9063��;O�&/3 )+2=79-727)P/9YE7r68762:-=79I524--2C)P/CY8O�&93�2479- 09>�3+&<*M682-,9&8YK7I3+O5'&/3�&<*,79-V3,(+*M682:6879I�2:--27)P/z*+2:3,DE3�2-3V6'09-:6'&)O�273�&21 &9,)(5)4273+5z79*,I�2C).*,79*H/ ,90bO�& 0'3<0'3�& 09> �A�����_3H/b3�)4&<Ac3<YI0C* &)66&930'3 0I) & &)*W3H/b3�)4&<Ac3 0CG1&<*,7I)4273+5(0'3e/'09(+*FI1& & 79-0>ZQ %'& &�&21 2:3@)4&/3�,9&>09>�A(0CI�24-7&<,90bO�&XB & 093+&�0C*@245'273e7I3+O&21 &/,<(5)+2-0'3 , & 79*.7I,/)4&)*+2:3@)427,<3z79*+&�)P/bG�27,d79-:-:/�3506)oB&)-4-`D 3�0rB;3 3�&/,9&<3H3+2C)�7I)+&<3 ) & &<&93K>N0C*@,9&)A &/3 )�09>$3@).*@2-,G)3+&/,<(+*@27)P/L,/0'3*).*+09-43 )40cG+*+&26'&/3 ) % *@0w§,763 & 0C*H3+&<3W763+OK06) & &<*o(�3;763*)+2-,92:G;7I)+&<OK&)i.&9,/),3<Qf]A3 ,9&)*@).762-3L,d783+&<3)Y27)�A?7d/lI.&oO�&)3+2:*.79I+-7& )40�G+*+0r6824O�&u*+&)G.&<7I)4&)Og*@&d79(5) & &93*)+2-,d7F)42-063g763KOc6879-724O;7I)+2-0'3�Y9G+-:(+3f*@&)660 ,<7I)4270'3g7I3+O,d7I, & &lO�&<-7&/)4270'3�793 3�&9&)O�&<O_Qv{ $ &/&($ &9,G)4270'3%/NQ � Q��bQ���� & &93O,/0CAUI�273�&<OnB;2C) & O�2:5'27).79-`3+24563;7I).(K*+&<37I3+OG+*@0 09>=s ,d79*H*H/82-3K5�,90bO�& )+0 &/3+3,(K*+&X79(5) & &93*)427,927)P/j763+OeGK*+0r6'&/3;763�,/&9Y�OK/83;79A(2-,d78-4-:/?--273+D6&)OkA(0CI�2:--& ,/0NO5&G+*@0�682:O�&<3u7 ,90CAcG.&)-4-72-3+5�0C*,5V7I3�2 � 2-3+5�G+*@2-3�,/24G+-7&W>N0C* & 2:5 & -0/g3H(+*H682:6879IK--&J3H/b3�)4&<Ac3<Q]A3xGK*+2-35,924GK--&9YwG+*@0CG.&)*,-0/<24AcG+--&)A &/3 )+&<O &93V6824*@0'3+A(&93*).3^>N0C*�&21 &9,)(5)4273+5FA(0CI�24-7& ,90bO�&�,<763�,/0'3*).*+2:I+(5)+&)40l3H(+*H682:6879I524--2C)P/ 273j6978*+2-09(+3�B�7d/b3<�

2 R 3;78I+--& ) & & &[15&/,<(5)+2-0'3 09>A?76, & 273�&2s 2-3+O5&<G1&93+O�&/3*) ).*,(K3@)PB�0C*@) & / G+*+0C59*.79Ac3 ) & 7I) & 7d66&�I.&/&93,<79*+&2>@(+-4-0/~763+79-:/ � &)O_Q %'& (K3<Y ) & &"G;78*.79O�2:5CA I1&9,/0CA(&<3L3�06)U§H(+3�)�Bo*@27)+&2sA063�,9&�*,(53NsZ763V/EB & &)*+&{�~�Jy � �[Y;I+(5)u*.7I) & &<*oBo*+2C)4&[sA0'3�,/&9Y+66&<*+20>�/VsA0'3�,/&9Y &935,d79G+3H(+-=7F)4&9Y�763KOe*,(53NsZ763V/EB & &)*+&j{�~�'�z�zsR�y � �[Q %'& 2:3,<763v5C*@&d7I),-:/(&93 & 763�,9&W3,(+*M6 206879I�24-727)P/�IV/?*+&)O+(�,9273+5>) & & 06) & &<*MB;243+&�&93�09*,A(0C(+3�).793,D08>�66&<*+20>�/82-3+5lA?763V/vO�20i &)*+&93*)o6'&)*,3@2-0'3+3M09>�) & &3,79A &�,/0NO5&9Q

2 R 3;78I+--&�7lO�243�)42-35,/)4270'3jI1&/)PB�&9&93 ) & & &21 &9,)(5)4270'3 08>TG+*@0C5C*.78A?3 0'3K2-3*),*+2-3K3+2-,<79-4-0/c(�3+*+&)--2479I+--&7I3+O(53+3+&/,<(+*@&j3+27)+&<3U>@*@0CA &21 &9,)(5)4270'3J0'3�*+&)--2=78I+--&c763+O�3@&9,)(+*+&a3+2C)4&)3<Q�]A3D) & &g3+&93K3+&L09>oAU(+-C)42:--&)66&<-3H(+*H68206978I�24-727)P/CY ,)*+2C)42-,<79- 0CG1&<*,7I)4270'3+3o3 & 09(+-4O 3506)WO5&<G1&93+O 063 ,90bO�&>09*�&[15&/,<(5)+2-0'3 0'3e-7&<3,3M).*H(+3@)MsB�0C*�) & /x3@27)+&<3<Q ¡ 0C*$7I3 0�� � ,/0'3�,9&)G5) )+0WI1&&93N>N0C*+,/&<O_YC3@0CA(&LA(&d793H(+*+&�09>;G+*@&<3,(KA &)O�3,(+I+3M/b3@)4&)A

g ���� �� blX�;�[7IJG�R\ ^���Ma78H[����A;!8f>H;!n�G N DHGMI�;rd��AD�� 6�#d�5C69= 5:;MY7;!=![7><6����=��A[CL9n'>HG��A;SECLKGM=!; d�6 >H5 ><5C;SGM8H8<;!I UCLKG�A;%�MN06�7EC[7><8 bAECD"���AD GMI�8�b8<>HG.><;'6�7N �ADHIJG.><6��� b0G7n �A[7><EC[7><8 b�; GM=H5 N D"�AI G�I [7L >H69ECL969=!6 >cV&�MNOnC6 �F;!DH;�l> 8H6 ><;!8 v�� �AD ;MY7GMI�ECL9;Ab�;MY7;!=![7><6��� = �A[7L9n > G��A;:ECLKGM=!;$��RqAGMDH6��A[788H6 ><;!8 b.E �A8<8H69UCL V 6� 8<69I [CL >HGC;��A[C8%nC698<><DH69U7[7>H;!n:ECD����ADHGMI�8en7V �GMI�69=�GML9L V GML9L��l= G.><;!n�GM8%DH;!8"�A[CDH=!;!8OGMDH; IJGMnC;iG�qMGM69LKGMUCL9;AbMd�6 >H5 d�69nC;!L V#8H=�G.>f>H;!DH;!nn�G.>HG�8��A[CD<=!;�8�b�GCnRDH;!8H[7L >H8�nC698H8<;!I�6��G.>H;!nRGM8 GME7ECD��AECD<6KG.>H;Av

wFw �

Page 138: Practical Architectures for Survivable Systems and Networks (Phase

3H(+*H68206978I�24-727)P/kAU(+3@) &[152:3@)>@*+09A�B & 2-, & ) & &g79595C*+&)5V7I)4&�3H(+*H68206978I�24-727)P/ ,d763hI.&(2-3N>N&<*,*@&<OO0C*O�&[s*@2:66&<O_Q

� & 2:5 & -0/�3,(+*M6 206879I+--& 0�66&<*,79-4-fA 0CI524--&[sA,/0NO�&c79*@, & 27)+&9,G).(+*@& ,d763�I1&j762:O�&<O�IV/�7 ,/0CAUI�273;7I)+2-0'3 09>).*H(+3@)PB�0C*�) & /h3+&<*M6'&)*,3<Y &93�,)*H/bG5)+&<OB35&/)PB�0C*,D ),*.7 �(,9Y`O�2:5'27).79-$3@245'3+7I).(+*@&<3)Y^GK*+0809>=sA,<79*,*M/ 273+5 ,90bO�&8Y�7I3+O06) & &<*�,90CAcG10'3�&93*),3$763KO>,9063�,9&)G5).3�O�243@,<(+3H3+&<O>2-3>$ &9,G)42-063�/NQ|�KQ %'& *+&/&,9063 )+&<AcG.09*.79*M/JO�08,/)409*.79-') & &<3@&<3G+*@0�682:O�&<24AcG.0C*�)�763*),90'3*).*@24I+( )42-063+3 )40 ) & &<&)3@)�78I+--2:3 & A(&93*);09>�3,(�, & 763�79*+, & 27)4&/,/),(+*+&8�

2 %'& &U>N0C*,A?79-0s¢A &G) & 0bO+3u-=763K5C(;795'&[sA,/&93*).*@2-,�,/0'3+3+2:O�&<*,7I)4270'3+3 08>LtF*@&)B t &d763�}���/w��Y &21NG+-70C*+273+5�) & &)P/bG1&2s¢3.78>N&G)P/L09>$ON/ 3+79A 27,J--273+D 2-3+5�273 � 7r687ws¢--2:D6& &/3E682:*+0'3+A(&93*),3

2 %'& &F3H/b3@)+&<A�sPG+*@06)4&/,/)+2-0'3Ns ,9&/3 ),*+27,WB09*,D 08>$tJ7I3 � 78-4-=7I, & }��C��3w��Y5,/0'3+3+2:O�&<*@2-3+5�) & &F(+3@&)>@(+-73�&<3H3 09>7I,9,9&)3,3�,/0'3*).*+09-43 273kB & 7F)�243�,d79-:--&<Oe7g3+&/,<(+*@27)P/VsPG+793,3@2-3+58s¢3@)P/b--&U79*+, & 2C)4&/,/).(K*+&xB;2C) & B�&<-:-0sPO5& � 3�&)O3@&<A?763*)427,<3<Y�B & 27, & &<AxI.0bO�2-&)3`3+0CA(& 09>5) & &fI1&/)@)4&)*$7I)@).*@24I+(5)+&<3�09>�,<79G;79I524--2C)P/VsPI;793@&<O3H/b3�)4&<Ac3T7I3+O2:3J3,G1&9,/2�� ,<79-4-0/ 0C*@2-&/3 )+&<OO)40rBL79*,OhA 09I�24-7&�,90bO�&9Y�&)A &)*,5'273+5a793�7�56&93�&)*.79-72 � 7F)42-063 09> & 243�&<79*,-72-&<*B�0C*HD�0'3a3@).76,�D 2-3+3HG.&/,/)+2-0'3

2 %'& &jG+*+0809>=sA,<79*,*M/82-3+5 ,90bO�&a79G+G+*@0V76, & 09> � &90C*H5'&jmM&9,<(K-=7�}|�8��3���Y�B & 2-, & >N0C*U7n5'2:66&93�A 09I�24-7&2s,/0NO5&'3+&<59A &/3 )�GK*+0r6824O�&)3�763c793,3@0 ,/2=7I)+&<O�G+*@0 09> ) & 7I) ,d7I3cI1&�OK/83;78A 27,d79-:-:/X763+O & �(,/2-&93*),-:/UGK*+0809>, & &9,�D6&)O )40k66&<*@2:>�/ ) & 7I)>2C) ,90C*H*+&<3HG.063+O+3xB;2C) & ) & &c5'2:66&93D,/0NO�&c3+&)5CA(&93*)�763KO ) & 7I)�) & & ,/0NO5&3@&<5CA(&93*) & 793u7�3@),*+0'3K5'&<*o3+&/3+3+& 09> 2-3*)4&)5C*+2C)P/ ) & 763K06) & &)*HB;2:3+&

2 %'& & $Kt<$b]M�'$K���J] sPI;793@&<O�2-3K>@*,793@),*,(�,G).(+*@&S>N0C*`O�2:3@),*+24IK(5)4&)O � 7d687z78G+G+--27,d7I)+2-0'3K3 09>;£�78-:>¥763 � Ywt &d763_Y7I3+O $NG+*+&/27) � &<*X}��43w��Y�2-35,<-4(KO�2-3+5l7�-70C5'2-,z>N0C*o76,9,/&<3H3�,/0'3*).*+09-£�76,�DE5C*@0C(�3+O�0'3 (53+O�&<*H3@).763+O�273+5B,/0NO�&aA(0CI�2:--27)P/"*.7F) & &)* 273+O�&<G1&93KO�&93*).-0/J09>F3H(+*H68206978I�24-727)P/�7I3+O

3+&/,<(+*@27)P/<2:3,3,(5&<3�243 5'206'&93 2-3�7'(+3@&)>@(+-b79*�)42-,)--&TIV/ ¡ (+5C56&/)+).7 &/)�79- QC}¦�d�C�8��{N2-3�7u3HG.&/,92479-'243H3,(�& 09>8) & & � ��� �� � ��� � � �����(� � � � ��� ����� � ��� � � ��� � ������� � ��0'3nA(0CI�2:--2C)P/a763+O 35&/)PB�0C*,DCsZ7dBL79*+& ,/0CA?GK(5)4273+5E�2Q ¡ 0C*,A?79-A(&/) & 0NO+3L79*+&F79-43@0UG;79*�)42-,)(+-=78*,-:/U*+&<-7&)68763*) )+0UA 09I�24-7&M,/0NO5&9Y+I1&9,<79(+3+&�08> ) & & ,)*+2C)42-,<79-�O�&<G1&93KO�&93�,/&<0'3)P/bG.&z3.78>N&G)P/Up >N09* &[1K79A?GK--&9Y*) & &z>N0C*HAg78--2 � 7I)4270'3>08> OK/83;79A(2-,u763+O?3@).7I)427,;)P/bG1& , & &/,�D 2-3+5x>N09*SA(0CI�2:--&,90bO�&5'206'&93K2-3h}��K�r�w� Q

� 3L&[1 ),*.7609*,O�273;79*H/ ,90CAcG�2:-=7I)+2-0'3 09>T78*@)427,<-7&<3 0'3j6879*@2-0C(+3�793,G1&9,G).3M09>�) & &A(0CI�24-7&2s ,90bO�&WG;78*.79O�2:5CA& 793uI1&9&93e793,3@&<AUIK--&<OeIE/ � 2-0r68763�352_� 24563;7KY�763+O�G+(+IK--243 & &<OkIV/ $bG+*+273+5'&<*'� &)*,-=785e}��C�K�)� Q %'& 243oI.080CD{@B & 2-, & ,90'3*).762-3+3 ,/0CG�270C(+3�*+&2>N&<*@&93�,/&<3���*+&�5 &9,G).3SA 093@) 09> ) & &oG.06)+&93*)42479-KGK*+0CI+-7&<Ac3$B;27) & A 0CI524--&�,90bO�&9Y763+OX3,(+595'&<3�).3 3E(+A(&<*@0C(+3T78G+G+*+0C76, & &<3 )40W*@&<O+(5,92-3K5�) & &L*+2:3,DE3<QTq0'3+3@24O�&)*+2-3K5�) & &�&/3�0C*,A(0C(+3�G.0I)4&93*)+2=79-24AcG;76,G)dY5) & 243uI10 0CD 243oAg7I3+O;7I)+0C*H/j*@&d79O52-3+5�>N0C*u763V/'063�&�),*H/82-3+5 )40c(+3@&�) & &XA(0CI�2:--&2s ,90bO�&FG;78*.79O�2:5CA2-3a3H(+G+G10C3+&)O+-:/j3H(+*H68206978I+--&3H/b3�)4&<Ac3<Q ¡ 0C-4-70rB;2-3+5�243o7lI+*+27&)>�3,(+AcAg78*H/ 09>�) & &I.080CD�Q

2 ��79*@)c]�,90'3+3@24O�&)*,3�) & &90C*@&/)427,d79-�>N09(�3+O;7I)+2-0'3K3<Yf763+OH2-3�,)-4(+O�&)3lG;79G1&<*,3lIV/ q & &)3,3�} /N�2�;0'3 I+793+27,2:3,3H(�&<3)Y;yM270C*,O+763a763+O $ , & 35&92-&)*�}��C�9�8�!063�DI&)/j56&93�&)*.7I)+2-0'3_Yb� 0C-4G+763�0l763+OK$bA 2C) & }��C�C�w�!0'3 ,90'3bs3�).*,762-3*).3 ) & 7I)o3 & 0C(+-4O�I1&�GK-=76,/&<OK0'3kGK*+0C5C*,79AcA 273+5U-=7I3+5C(;7956&<3'>N0C*'A(0CI�24-7& ,90bO�&8Y�763+O $K763+O�&)*7I3+O % 3@, & (KO�2-3�}��C�C���10'3 ) & &z*@0C--&)3�08>!,<*M/bG5)40C59*.79G & /(2-3c3+08> )PB�79*@&2s¢I;793+&)Oa79G+G+*@0V76, & &)3�)+0X3@&9,<(K*+&A(0CI�2:--&�,90bO�&9Q

2 ��79*@)o]H] ,90'3+3@24O�&)*,3o*+&)--&2697I3 )�3+&9,)(+*+2C)P/jA(&9, & 7635243,Ac3<Q�mM&9,)(+-=7l763+O � &9&c}��9��/r�_>@(+*�) & &)* &<-=78I.0C*,7I)4&063K) & &G+*+0809>=sA,<79*,*M/82-3+5�,/0NO�& ,9063�,9&)G5)dY�5'206 273+5c7cGK*+06)+06)P/bG�2-,<79- O�&<3@245'3k763+OK, & 79*,76,/)+&<*@2 � 273+5 27),32:A?GK--&<A(&93*).7I)4270'3_Q ��0 & -�}¦�r�9�8� &21NG+-70C*+&)3 ) & &*+09--& 09> ,90bO�&�0CIN>@(+3+,<7I)4270'3"{@B & 27, & A?79D6&)3o*+&)66&<*H3+&

w �

Page 139: Practical Architectures for Survivable Systems and Networks (Phase

&/3+5'273�&9&)*+2-3K5XO�2 �(,<(+-C)[��2-3cG+*@06)4&/,/)4273+5U785V762-3K3@)�A?79--27,92-09(+3 ,90bO�&8Q�£&<*HD60r6827).3�&/)L79- Q;} � �)�.,/0'3+3@24O�&)**@0C--&)3>09>u78(5) & &/3*)42-,<7I)4270'3_��,/&<*@)+2�� ,<7I)4270'3B) & 7I)�7k3+&<*M6'&)* & 793UG+*@0CG.&)*U79( ) & 0C*@27)P/9Y�79-4-70 ,<7I)4270'3O09>-7&d793�)oG+*+206824--&)5'&9YK763+O�3@).7I)4&�79G+GK*.762:3.79-1)40(&93+3H(+*+& 2-3*)4&)5C*+2C)P/CQT� 245'3;7a}��C�C�w� ,90'3K3+24O5&<*,3;) & &�(K3+&<09>&[1 &9,<( )42-063 ),*.76,/&<3^763+O ,<*M/NG )40C5C*,79G & /�)40oO�&G)4&/,/)$7I)+).76,�DE3$795C762-3+3�) ,90bO�& , & 763K5'&<3)Y93@).7I)4& , & 7I3+5'&<3)Y7I3+OL&21 &9,)(5)4270'315 0rB 09>$A(0CI�2:--&�,90bO�&9Q

2 ��79*@)v],],]�,/0'3+3@24O�&)*,3j3+09A &n3HG.&/,92�� ,nA(0CI�24-7&2s ,90bO�&k3M/b3@)4&)A?3)Y � *.7d/�&/)a78- QW}¦�C�d�w� 273~t � � 5'&/3 ),3{�>N0C*,A(&<*H-:/ ,d79-:--&<O � 5'&93*) % ,<-��[Y��79*@§@0I) & }¦� 39��� 2-3 ]Z£ 0 ��3 � 5C--&G).3a3H/b3�)4&<A�Y�763+O � 063+5 7I3+O$8, & &<A(&<*H3�} �C� /r��2-3 G+*@06)4&/,/)+2-3+5�763KO ,)*H/bG5)+0C5C*.78G & 2-,<79-4-0/ 3@245'352-3+5 � 7d687 0CIb§@&/,/).3vp 3@245'3�273+5+Y3@&d79-72-3+5KY+763+O�5C(;78*,O�273+5+Q

2 ��79*@)L]¢�#,/0'3+3+2:O�&<*H3) & &W3+&/,<(+*@& & 763+OK--2-3K5>09> A(0CI�2:--&;,90bO�&�0'3 ) & & �B09*,-4O � 24O�&�� &<I_Qf�F(+3@)+&<*Zs& 0C(5)M&/)W79- Q^}��4/9���^O�&<3@,<*+2:I.&>$K78>N&[s % ,)- Q�t &<�$7609--2 &/)W79-�Q^}��C�w�`3,(+AcAg78*+2 � &�) & &6b(+--3�&)*.79I524--2C)427&<3 2736879*@2-0C(K3�3+08s ,d79-:--&)O � 3+&9,)(+*+&�� � &<I�I+*@0�Bo3@&<*H3<Q

� ������� � ( � � �J1 � � * 1 " � -�� ( � � � � � ( � 1��'- �

%'& &<3�06)+2-0'3 08>T7�,9063�� 3�&)O &21 &/,<(5)+2-0'3L&93V6824*@0'3+A(&93*)u5'08&<3'I;76,�Da7F)o--&d783@)o793;&<79*,-0/j793 0k(K-7)427,<3)Q %'& &3�&)3@)4&)O 0k(+-C)427,<3o*+273+5C3 09>$G+*+06)+&9,G)42-063�B�&<*@&x(+3@&)>@(+- >N0C*oG+*@06)4&/,/)4273+5 ) & &�3H/b3@)+&<A 795V7I2-3+3�);27).3u79GKG+--27,d7ws)4270'3+3o763KOkG+*@06)4&/,/)+2-3+5(27),3o79G+G+-72-,d7F)42-063+3{ &8Q|5KQ:Y;3@09> )PB�78*+&9Y�O;7F)�7V�'795V7I2-3+3�) ) & &/24*'(+3@&<*,3)Q �M0�B�&)66&<*)Y.) & &*+273+5C3L79*+&J78-43+0X*+&)--&)68763*) )+0U3H/b3�)4&<A�3,(+*M682:6879I�2:--27)P/ �N7xG+*@0CI+--&)A 2-3v*@2-3+5v� ,90C(+-:O�3�06)LI+*+273+5UO�0rB;3 ) & &3H/b3�)4&<A�sA,)*+2C)42-,<79- ,90bO�& 273 *+273+5��KYTIK(5)�A(245 & )�,<*.783 & 7e(+3@&<*�G+*@0 ,/&<3H3 �f7nG+*+0CIK--&<A 273 *+273+5��kA(245 & )79I10C*@)U7n(+3+&)*�,90CAcA?763+O I+( )UB09(+-4O 3�0I)�,<*,793 & ) & &j(+3+&)*�G+*+08,9&)3,3���7nG+*@0CI+--&)A 273�763 0C( )4&<*x*+2-3K5A(245 & ) )P/bG�27,d79-:-:/?3+24563;79- 763K&<*H*+0C*'*@&/),(+*+3aB;27) & 0C(5);06) & &<*MB;243@&x78i.&9,G)4273+5�*,(�353�2-3+5cG+*@0 ,/&<3,3@&<3)Q

]PAcG.0C*�)�763*)a3H(+I+3+&)\E(�&93*)�*+&)3+&<79*+, & ,<79A(&�>@*@0CA 0 27, & 76&)->$8, & *+08&<O�&)*�}���3N�8Yz�439�w�?{ & 243aO�08,/)+0C*.79-) & &<3+2:3 0'3kO�0CA?762-3K3M08>�G+*+0I)4&9,G)4270'3n763KOeAU(5),(;79-`3,(K3,G�27,92-063e5C*@&)B 0C(5)�09> ) & &�0�(+-7)+2-,<3uG+*@0w§@&9,G)[�z7I3+O£L(5),--&)* �`79A?GK3+0'3 } �r�C��� YTB;2C) & -=7F)4&<*XB0C*HD�IV/���79(+- �79*H5'&<*v}¦��39�8� 063�G+*+&26'&93*)+2-3+5 % *+0w§,763 & 09*,3+&)32-3h7L,90'3V66&93*)4270'3;79-S76,/,9&<3H3�&/3V6 2:*+0'3KA &/3 )g{ ) & 7I) 2:3<Y�3�06)�AU(+-C)42:--&)66&<-�3+&9,)(+*+&d�2Q?]PO�&d79-:-:/9Y 27)3 & 0C(+-4OhI1&G10C3,3@24I+-7& )+0 ,/0'3*).*@0C- &21 &9,)(5)4270'3B273"3H(�, & 7jB�7d/O) & 7F)�3506) & 273+5k79OK6'&)*,3@& ,d7I3�G10C3,3@24I+-0/ & 79G+G1&93�Qv]A3G+*,76,/)+2-,9&8Y 09> ,90C(+*H3+&8Y�) & &<, & 79-:--&/3+5'&<3u79*@&JAU(�, & A 0C*@&JO�2 �(,)(+-7)<Q

%'& & � 7r687a� 24*�).(;78-:0e76, & 273�&�{ � � 0n��243X763B&[1K79A?GK--& 09>o763 &21 &9,)(5)4270'3D&/3E682:*+0'3+A(&93*)XO�&<3@245'35&<O)40 &935,d79G+3H(+-=7F)4& ) & &K&21 &9,)(5)4270'3 09> ,90bO�&K) & 7I) ,d763 I.&�OK/83;79A(2-,<79-4-0/D0CI )�76273�&<O 763+O --0V79O5&<O�>@*+0CA79*HI�27),*.79*M/U3+09(+*+,/&<3<YN3,(+IE§@&9,/) )40�3,(527)�78I+--&'3@&9,<(K*+27)P/ ,/0'3*).*@0C-43)Q % 095'&/) & &<*�B;27) & ) & & � 7r687�t &)66&<--09G+A &/3*)��27)F{ � t����u}¦�C� � Y¤�9�r�w��Y � �!0 )�79DI&<3'7X3+24563�2�� ,<763*)�3�)4&<G )40rB�78*,Oj--2:A 2C)4273+5JI;79O�&2i &/,/),3) & 7F) ,d7I3 )�79DI&G+-476,9&�273 &21 &9,)(5)4270'3 08>�763h79GKG+--&G)<0CI5)�7I2-3�&)O�>@*@0CA 7jG106)4&/3*)42=78-4-:/�(�3*),*,(+3�)PB0C*�) & /h3+2C)4&9Q %'& 243�2:3763&21K79AcG+-7& 09>�7 ,/0'3*).*+09-4--&)O &[1 &9,<( )42-063 O�0CA?762-3�B & 093+&�273 )+&93*)�243<)40e*,79O�27,d79-:-:/k--24A(27)WB & 7I)�,d763�7I3+O,d7I3�3�06)LI.&zO�0'3�&8Y 2:*,*+&)3,G1&9,G)42:66& 09>!) & &W3@0C(+*@,9& 09> ) & &W79G+G+-7&/)dQ $b/b3@)4&)A?3LO�&<3@245'3�&)O )40X3,(+GKG.0C*�)�3@&9,<(K*+&763+O�*@&<--2479I+-7&>&21 &/,<(5)+2-0'3O09> ).*H(+3@)PB�0C*@) & /�A 09I�24-7&>,90bO�&�,<763 & 7d6'&c763O2-3 & &<*+&/3*)XG106)+&93*)42479-$3�)�79I�2:--2C)P/CQ��0rB�&)66&<*<Y � � 0:243�3506)F/'&G)X7 )+06)�78-T3+0C-:(5)4270'3_Y.2-3 ) & 7F)�27)�2:3JO�& ��3�&<O 0'3+-0/ 2-3 )+&<*HA?3�09>f3+273+5C-7&2sP(K3+&<*3H/b3�)4&<Ac3 � 2C)oO�0 &)3;3�06)oG+*@0�682:O�&G+*+06)+&9,G)42-063K08>�0'35&�(K3+&<*'>@*@0CA 763�0I) & &)*'3+24Ax(+-7).763�&909(+3'(+3+&)*<Q

%'& &j3HG.&/,92���,K&[1 &9,<( )42-063�&/3E682:*+0'3+A(&93*),3cGK*+0r6824O�&)O�IV/ � 7d687KY ) & & � 7d687n� 2:*@).(+79- 0e7I, & 2-3�&8YL7I3+O) & & � 7d697XIE/ )+&9,90bO�& & 7d66&J3+0CA(&W3@&<*+270C(+3�G106)+&93*)42479-¤3@&9,)(+*+2C)P/gG+*@0CI+-7&<Ac3<YK-479*,56&<-:/c7F)+).*@24I+( )�79I+-7& )40�) & &&9350C*,A(27)P/ 08> ) & & ,90bO�&XI;793+&x763+OK) & &>¥76,/)M) & 7I)F7l6'&)*H/�-=79*H5'&G.09*@)4270'3K09>�) & 7I)�,90bO�&xAU(K3@)zI.& ,90'3bs3+2:O�&<*@&<OL)40cI.&JB;2C) & 273L) & &<&)i.&9,G)42:66& ),*,(+3�)4&)O ,909A?G+( )42-3K5�I;793+&Fp B & 27, & )40c7 �;*,3�)z79G+G+*@0r1 2:Ag7I)+2-0'32-35,<-4(KO�&<3fA 0C3�)08> ) & &z*,(�3Ns )42:A &u3,(+GKG.0C*�)dY8) & &zIE/ )+&9,90bO�&F66&<*+2�� &<*)Y ) & &W-70 ,<79- 0CG.&)*.7I)+2-3+5X3H/b3@)+&<A�Y5) & &

w w

Page 140: Practical Architectures for Survivable Systems and Networks (Phase

I+*@0�Bo3@&<*�3@09> )PBL79*+&8Y5) & &z3+&)*H6'&)*,3�>@*@0CA�B & 2-, & ,/0NO5& 243�0CI5).762-3�&)O_YN763+O ) & & 3�&G)PB09*,D 2-3+5�3@09> )PBL79*+&8Q � -0s) & 0C(+5 & ) & 2:3 &/3�0C*HA 0C(K3f3@&9,<(K*+27)P/cG1&<*@24A(&/)4&)* ,90C(+-:O?I1&u3 & *H(�3+Dl3+0CA(&)B & 7I)LIV/ )4&/, & 3�2:\b(5&<3LO5243+,)(+3,3@&<OI1&<--0rBY5) & &3+&/,<(+*@27)P/aG1&<*+2:A &G)4&)*�>N0C* � � 0 79G+G+-7&/)o3@&9,<(K*+27)P/L2:3�6'&)*H/a-=78*,5'&8Q

]A3L,90'35,9&<G )dY;A?763V/vG+*@0CI+--&)A?3,d763aI1&JAg79O5&WB09*,3+&IV/�) & &JG+*+&)3+&/3�,9& 09>^A 09I�24-7& ,90bO�&�273 & &/)+&<*+0ws5'&/3�&90C(K3 35&/)PB�0C*,DI&<O�3M/b3@)4&)A?3)Q �M0�B�&)66&<*)Y$7gB�&<-:-0sA&/3+5'273�&9&)*+&<O�7I3+O�G+*+0CG1&<*H-:/ &93�,<79G+3H(+-=7I)+&<O�6824*�).(;79-A?76, & 2-35& &93V6824*@0'3+A(&93*) & 793 ) & &�G106)4&/3*)42=78-509>10r6'&)*+,909A 273+5JAg7I3E/�09> ) & &'*+2:3,DE3 ) & 7F)�A 2:5 & )�0I) & &)*HB;243@&79*@243+& 273�) & &o(+3@&M08>_79*HI�27),*.79*M/xGK*+0C5C*,79AcA 273+5F-=7I3+5C(;7956&<3�763+O�) & &;&21 &9,)(5)4270'3 08>_79*HI�27),*.79*M/>,/0NO5&9Q � &I1&<--27&)66& ) & 7I);) & &JA 09I�24-7&2sA,/0NO5&FG;79*,79O�2459A & 783M&/3�0C*HA 0C(K3'G.06)+&93*)42479-�B;2C) & *+&)3,G1&9,/)M)40l3H(+*H682:6879I524--2C)P/{�7I3+O ) & &�G106)4&/3*)42=78-�)40vB;2C) & 3�)�763+O�>N0C*@,9&<O�3M/N3�)4&)A ,<*.783 & &)3<Y^--0C3H3�09>S3+&9,)(+*+2C)P/CY^76,/,924O5&93*)�79- 09(5)�7956&<3<Y763+O�3+0 0'3;�2Y;I1&9,d78(+3+&<09>�) & &*@0C--&)3 27);,d7I3�GK-=7d/ 2-3 273+O+(�,/2-3+5c7�3,(K*H682:6879I+-7&79*+, & 27)4&/,/),(+*.79- 3�).*H(�,/),(+*+&8Q£L(5);) & 7I);2-3L2C).3+&)-:>`>N0C*@,9&<3o(+3;)40�) & 2-3+Dg79I10C(5) ) & &�GK*+0CI+-7&<Ac3 27)o*,76243@&<3<Q

%'& &)*+& 2:3�08>�,90C(+*H3+&W7�,9063.5 2-,G)�I1&/)PB�&9&/3L) & &WO5&<3+2:*+&;)40UGK*+0r6824O�&�&218)4&/3+3+206'&W>@(�35,/)4270'3;79-727)P/l7I3+O ) & &3�&/&<O )40�,9063+3@),*.76273�0C* ,90'3 � 3�& ) & &�>@(�3�,/)+2-0'3+79--2C)P/ )+0Ag79DI& 27)T3+&9,)(+*+&Lp 273�0C*,O5&<* )40 & &<-4G�) & & 0r6'&<*,79-4-,909A?G+( )4&<*ZsA,/0CA?Ax(�3�2-,<7I)4270'3�&/3E682:*+0'3+A(&93*)uI1&J3,(+*M6 206879I+--&(�3KO�&<*u7I)@)�76,�DE3<Q

�W>SG;79*@)+2-,)(+-=79*W*+&<-7&)68763�,/& & &<*@&c79*+&�) & &c763;79-0/N3@&<3�09>LtF*+&2B�t &<763 }��4/w��763+OhtJ763 ��79-4-476, & }��C��3w�09> ) & & � 7d687K$ &9,)(+*+2C)P/%0e763;785'&<*?{ � $.0n�2Y_B & 27, & 2:3�2-3*)4&/3+O�&)O )+0�I1&l7a3+&9,)(+*+2C)P/�*+&2>N&<*@&93�,/&?A(0'3�2C)40C*) & 7I)FA(&<O�247I)4&)3F79-:-�3@&9,)(+*+2C)P/Es¢*+&)--&)68763*)7I,9,9&)3,3@&<3<Q � *@&)>N&<*@&93�,/&�A 063�27)+0C*�2:3W3H(+G+G10C3+&)OO)+0 & 7d6'&�) & *+&/&>@(�3+O+79A &/3*)�79-�G+*@0CG1&<*@)+2-&)3<�g{M��� 2C)<243�79-:BL7d/b3�273E660CD6&)O~{N3�0'3EIV/NG+793,3,79I�24-727)P/K�2YL{ �9��2C)<243�)�78A?G1&<*HG+*+0809>ZY763+O�{��C�27) 2:3'3,A?79-4-!&/3�0C(+5 & )+0cI1&�) & 09*+0C(+5 & -:/v763;79-0/ � &<O"{@66&<*@2���79I524--2C)P/K�2Q � 3K>N0C*@),(�3;7I)+&<-0/CY�CQ %'& & � $.0 243 3506)f79-:BL7d/N3 273E660CD6&)O_Q���*+0C59*.79AcA &)*,3�AU(K3@)S*+&)A &)AUI.&)* )40 ,d79-:-�27)<Q$]¢>.) & &2/�O�0 3�06)dY) & &O�&)>¥78(+-7) 2:3 ) & 7I)u7I,9,9&)3,3M243'5C*,763*)4&)O_Q

�NQ %'& & � $-0 2:33�06) )�78A?G1&<*HG+*+0809>ZQ %'& & )P/bG.&F3M/b3@)4&)A ,<763vI1& ,90CAcG+*@0CA 2:3+&)O_YVB & 2-, & 273 ).(K*+3�,<763(53+O�&<*HA 273�& ) & & � $.0 3@&9,<(K*+27)P/9Q

�KQ %'& & � $-0 & 793�3�0j>N0C*,A?79-^I;793@243<Y`7I3+OO27).3 ,90CAcG+--&[1 27)P/k--&<O )+0 5�7dBo3 273�3+&/,<(+*@27)P/�G10C--27,927&<3 &)AlsI1&<OKO�&<OK2-3 � t����9Q �l763+Okm�&G).3@,d79G1&xmz7d6 2:5V7I)+0C*o�NQ|� ��3 $8&9,<(K*+27)P/.0e7I3;795'&)*<Q

]A3 79O+O�2C)42-063_Y�I.0I) & t &d763 763+O ��79-4-476, & 3�06)+&L) & 7I)�) & & � 7r687�-=763K5C(;795'& 27).3@&<-0>F763KOH2C).3�2:A?G+-7&2sA(&93*)�7I)+2-0'3K3LO�0�3506) & 7d66&763V/v79(KO�27)+2-3+5�>¥76,92:--27)P/9YE763+O�) & (K3 ,90CAcG+-7&/)4&)-:/l>¥762:- )+0U3.7F)4243M>�/ ) & & % q $NRfq76,/,90C(�3*).79I�24-727)P/g763+Ok79(+O�2C)4273+5�*+&)\b(524*+&)A &/3*).3<Q� ������� � 1 '(�" - � ( � � � � ��� 1 " -�� � � �%1 � " �� 3�&08>�) & &fG+*+09I+--&)A?3�793,3@0 ,/2=7I)+&<O�B;27) & ) & &fA 09I�24-7&2sA,/0NO5&�G;79*.78O�245CA 2:3�) & 7I) 27)�243$7 � � ��� A(0NO�&S*.7F) & &)*) & 763a7 � �A���XA(0NO5& 09>�0CG1&<*,7I)4270'3_QT] ) ,/0C(+-:OjI.&J78OK68763*)�795'&/0C(+3 )+0 & 7d6'&J3,(KI+3+&)\b(5&93*) 2:A?G+*@0r6'&<A(&93*),379(5)+0CA?7I)427,d79-:-:/�O�0rB;3+--0C79O�&<O�Y+79-C) & 0C(K5 & ) & 7I)L79-:3+0 ,<*+&<7I)4&)3LG106)4&/3*)42=78-1273*)4&<59*+27)P/UG+*+0CIK--&<Ac3<Q ¡ (+*@) & &<*ZsA(0C*+&8YF) & &<*@&�79*@&�,<793+&)3�2-3B & 27, & 27)^A?7r/FI.&SO�&<3@24*,79I+--& 0C*�&)66&93�3�&/,9&)3,3.78*H/ )40W*@&)660CD6& 273+3@).763*)�7635&90C(+3H-:/79-:-;76,9,/&<3H3+&<3 )+0�&[1 243@)+2-3+5 ,909G�2-&)3 08> 7XG+79*@)+2-,<(K-=79*$66&<*H3+2-063 09>_7XG+*@0C5C*.78A 0C*�O;7I).7KQ���0rB�&)66&<*<Y5&21 243�)42-3K5I+*@0�Bo3@&<*H3'5'&93�&)*.79-:-:/cG+*@&)>N&<*L--08,d79-:-:/�,<76, & &)Oa66&<*H3+2-063+3 )40�35&)B�&<*L66&<*,3@2-0'3K3<Q %'& &�2-3K3@)�7I3 ).763�&/0C(+3�*@&)6'0ws,d7F)42-063cGK*+0CI+-7&<A BL793 2-3V6'&)3@)+245V7I)+&<O(2-3 ) & &�r�4/9�93 2-3�) & &�,/0'3*)4&218)�09>!,<79G;79I524--2C)P/VsPI;793@&<Oc79*@, & 27)+&9,/),(+*+&)3{ &8Q|5KQ:Y^} �r�C�bY �r�V�bY �9�r�NY � � /bY � 3N�8Y��9�C�����[Y;I.&)5'2-3�352-3+5UB;2C) & tJ7d6 2:O�yM&)O�&<-:- ��3 ) & &)3+243X}��K�r�bY��K� /���Q� 3KO�&<*?yM&)O�&<-:- ��3l3+, & &)A &8Y'*+&)660 ,<79I+-7&e76,/,9&)3,3g*@&<\E(�2:*+&<3?763�&218).*,7"--&26'&)-M08> 2-3KO�24*@&9,/)+2-0'3 ) & *+0C(K5 &

7 O5&<3+2:5'3;7I)+&<O Ag793�)4&)* ,<79G;79I�2:--2C)P/CYF3@0�) & 7I)e*@&)660 ,<7I)4270'3 09>�79-4-�,/0CG�2-&)3 08>l7 5'206'&/3 0CIb§@&/,/) ,90C(+-:OI1& &2i &/,/)4&)O 3@24AcG+-:/�IE/�O5243.78I+--273+5 ) & &a5'206'&93 Ag783@)4&)* ,d79G;78I�24-727)P/CQ {�B&L,909(+-4O 79-43@0O,90'3*)4&)A?GK-=7I)+&

w

Page 141: Practical Architectures for Survivable Systems and Networks (Phase

7�O�243�).*+2:I+(5)+&<O�3+&/) 09> &)\E(�2:6879-7&93*)(,d79G;78I�24-727)427&<3>) & 7I) ,90C(K-4OH2-3�7"G+*,76,/)+2-,<79-'3+&/3+3+&kI.&�O�243,79I+-7&<O�3+20sAU(+-C)�7635&90C(+3H-:/9Q�� % 0�76, & 2-&26'&a7n3@24A(24-=78* &2i &/,/) 273B) & & ,/0'3*)4&[1 ) 08>M) & & � �o�z�JR�y � A(0CI�2:--&[sA,90bO�&G;79*,79O�2:5CA�B;2C) & 0C( )�(�3+O�&)*,A(2-3�273+5�) & &oG1&<*H>N09*,A?763�,9&oI1&93�& ��).3 ) & 7I)S*+&<3H(+-7)�>@*@0CA ,<76, & 2-3K5+YE3+0CA(&o3+0C*�)09> ,/0CAcG+*+0CA(243@&oG+(+3 & sPG+(+-:-�A &/, & 763�2:3,A 243 3�&9&)O�&<O�)+0�&/3+3,(K*+& ) & & ,)(+*,*@&93�,2/ 09> 7X--08,d78-4-:/>,d76, & &<O 0CINs§@&9,G)dQ � -7) & 0C(+5 & 2-3+3�)�763*).763�&909(+3f*@&)660 ,<7I)4270'3?3@&9&)A?3�2-3*).*@2-3+3@2-,d78-4-:/�2-35,90CAcG;7I)+24I+-7&LB;27) & -70 ,<79- ,d76, & 2-3+5+Y6879*+270C(+3�79-C)4&)*+3;7I)+2:66&<3 &21 2:3@)dQS� 3�&u79GKG+*+0V7I, & B�0C(+-:O?I1&u73@2-3+59--& ,<(K*,*+&/3�,)/lI527) ) & 7I) 243�(+G�O;7I)+&<OcG.&)*+20s0bO�2-,<79-4-0/CYC7I3+O , & &9,�D6&)OgB & &/3�&)66&<*'76,/,9&)3,3�>@*+0CA 7 ,<76, & &<Oc6'&)*,3+270'3(243�7I)@)4&<AcG5)+&<Oxp >N0C*+,/2-3+5JO�&)--&G)42-06309>�) & &<,<76, & &<O 0CIb§@&/,/);) & *@0C(+5 & OK/83;79A(2-,J*@&<-70V79O�273+5UB & &935&)6'&)*�) & &<,<(+*H*+&935,)/aI�2C) & 793oI.&/&93�*+&)3+&/)<Q

� ������� � � (�( � & � � � � � � � � ( � 1

%'& &I;793@2-,FB�0C*,D 0'3jG+*+0809>=s ,d79*H*H/82-3+5�,/0NO5&c{ $ &/,/)4270'313NQ|�V��,909A &)3�>@*+0CA � &/0C*,5'&Fm�&9,)(+-=7�}��9��3w��Q�R�76, &,90bO�&�A(0NOK(+--&�,d79*H*+2-&)3WB;27) & 27)WG+*+0809>@3J79I10C(5) ,9&<*�)�76273n6827)�78-$G+*@0CG.&)*@)+2-&<3 09> ) & &�,/0NO�&8Q %'& &U6879-724O�2C)P/09> ) & &xGK*+0809>@3�,<763nI1&x*@&d79O�2:-:/j66&<*+2�� &<OeIE/e7?*,7I) & &<*W3@24AcG+--&�763KOn*+&)-=7I)+2:6'&)-:/v>¥783@)FGK*+0809> , & &/,�D6&)*<QJ]¢>) & &JG+*+0809>@3273+O�&/&<OL2-3V6'09-:6'& ,<*+2C)427,d79-�G+*+09G.&)*@)427&<3)Y�2-3vGK*+2-35,924GK--&F7I3E/v79OK66&<*,3@&�79-7)+&<*.7F)42-063+3 )+0�) & &�,/0NO5&{¥A?79-72-,9270C(+3�0C* 06) & &<*HB;2:3+&d�o78*+&J--2:D6&)-:/ )+0l*+&<3H(+-7)M273�) & &G+*@0 09>@3'>¥762:--273+5+Q

� ������� � � "F �!- 1 " - � �%1 � � "S" ( ( �J - � � � � �'-�� � � -0/ ( � - � � ( � � � 1 � ( � 1

%'& &h3,(+*M682:6879I+-7& &21 &9,)(5)4270'3 09>X(�3*).*H(+3@)PB�0C*�) & / A(0CI�2:--& ,90bO�&�O�&<G1&93+OK3 0'3 ) & &"3H(�,9,/&<3,3M>@(+- 243+09-=7ws)4270'3 08> ) & &�&21 &9,)(5)4270'3_Y+G+*@&)66&93*)4273+5�,90'3*).79A 273;7I)+2-0'3_Y 273K>N0C*,A?7I)+2-0'3l--&<79Dw795'&8YN7I3+OjO�&9352=79-:3�09>`3@&<*M6 27,9&8Q� & 7I) 2:3>3�&/&<O�&)O 273 3H/b3@)+&<A 763KO 3�&/)PB�0C*,D 79*+, & 2C)4&/,/).(K*+&<3 273E660C-:66&<3l7 ,/0CAUI�273;7I)4270'3D09>u-4763+5C(;785'&2s0C*@2-&93*)+&<O�6824*@),(;79-SAg7I, & 2-3�&)3l793�2-3 � � 0 }¦�9�r�8��YS3,763+O+I10d1 &<3k}¦�9� � Y��d�K�)��Y�O�2:i.&<*@&93*)42479-LOK/83;78A 27,v76,[s,9&)3,3�,/0'3*).*+09-43l}��C�C��� Y¤A &)O�2=7I)+0C*,3)Y.),*,(+3�)4&<O�G+7I) & 3�)40 ) & &�&93KOh(K3+&<*)Y_--&)3,3ZsPG1&<*,A(243H3+206'&xIV/ )4&/,90bO�&U6'&)*+2¦s� &)*,3<Y5,<*H/bG5)+0C5C*,79G & /h}��C�C�w��Y;763KOvB & 7I)4&26'&)*z78(5) & &/3*)42-,<7I)4270'3_YNO�245'2C)�79-:-:/�3@245'35&<O ,90bO�&8Y+G+*+0809>=s ,d79*H*H/82-3+5,90bO�&�}��9��3EY��9�9�w��Y�763+O 06) & &<*�2-3K>@*,793@),*,(�,G).(+*,79-�,/0'3+3�).*.7I2-3*).3UA?7d/B&/3+3,(K*+&�) & 7I)>) & &v*+2:3,DE3�09>oA(0CI�2:--&,90bO�& ,d763 I1& ,/0'3*).*+09-4--&)O_Q m�06)g3,(+*HG+*+2:3+273+5C-:/9Y�A?763V/J09>�) & &)3+&n*@&<\E(�2:3+27)+&eA(&9, & 7I3�243HA?3g79*+&�O�&<3@24*Zs79I+-7&F>N0C*'A(0C3@)oA(&d76352-3+59>@(K-4-:/c3H(+*H682:6879IK--&<&93V6824*@0'3+A(&93*).3)Y;I+(5);) & &O�&)3+2:*.79I�2:--2C)P/ 09>�) & &�A(0CI�2:--&[sA,90bO�&G;79*,79O�2:5CA�A?79D6&)3 ) & &lG.0I)4&93*)+2=79-T6b(+-73�&<*,79I�24-727)+2-&<3zAU(�, & A 0C*@&l(+*,5'&/3*)Jp 763KO 273+O�&9&)O�O+*,79A?7I)42 � &<3) & &�56&93�&)*+2-,G+*@0CI+-7&<Ac3LB & &93 2-3*)4&)*,G+*@&/)+&<Ok79G+G+*@0CG+*+247I)4&)-:/gI+*+0V78O+-:/9Q

��

� � � � � � �5�� � � � � � � ���� ��� � � � ����A5�� � � ��� � � � � � � � �

]A3n3@&)6'&)*.79-�G+*+&2682-0C(+3u3+&/,/)+2-0'3+3�09> ) & 243u*+&)G.0C*�)dY;B�& & 7d6'&�3�06)4&)O ) & &>&9350C*,A(0C(+3uG.0I)4&93*)+2=79-:3o>N09*uB;2:*+&2s--&)3,3(&93+ObsP(+3@&<* ,/0CAcG+(5)4273+5+Q �$79*�)427,<(+-479*,-0/D2-3H,909AUI�2-3+7I)4270'3 B;27) & ) & &K) & 2-3bsA,<-72-&/3 )l(K3+&<*?G+-=7F),>N0C*HA?3O�2:3+,<(K3,3+&)O 2-3B$ &9,G)4270'3 /NQ � Q � Y�B;2:*+&)--&<3H3�,/0CAcAU(�3�27,d7I)+2-0'3+3�79*@&g78-4*+&<79OK/�I1&<562-3�3�273+5L)40e*@&)660C-4(5)+2-0'352 � &) & &K,/0CAcG+(5)4&)*Ms ,90CAcAU(�3�27,d7I)+2-0'3 )4&/, & 3�0C-70C59/CQ ��0rB&26'&)*<Y) & &aG.06)+&93*)42479-�*@243,DE3�)+0 273*)4&<59*+27)P/9Y ,90'3��NsO�&/3 )+2=79-727)P/9YL763KO 7d687624-479I�2:--27)P/"79*@&�79-43@0 &/3�0C*,A(0C(+3)Y�763KO ,9063+3+&)\b(5&93*).-0/ 3@&<*@2-0C(+3?79*@, & 27)+&9,/),(+*.78-z7I3+O0CG1&<*,7I)4270'3;79-o79GKG+*+0V7I, & &<3j78*+& 35&9,9&)3,3,79*H/9Q � 3 795C5C*@&<3,3@2:66& ,90CAxI�2-3;7F)42-063H08>J--273+D &93�,)*H/bG5)+2-0'3~7I3+O&93KONs )+08sA&/3+O &/3�,<*M/bG5)4270'3 2:3 0'3+-0/�G;79*�) 09> ) & &o3+0C-:(5)4270'3_Q���*@06)4&/,/)+2-0'3?795V76273+3@)TO�&93�2479-43 08>_3+&)*H682-,/&;243 &<3Zs3+&/3*)42=78- Q � 3+O�&)* 3�0C*HAg78-809G.&)*.7I)+2-0'3+3)Y6,/0'3V6'&93*)+2-0'3;78-5&935,<*H/bG5)+&<O ,909A?AU(53�2-,<7I)4270'3+3^Ag7d/I1&'79O�&)\b(+7I)4&8Q��0rB�&)66&<*<Yb(�3+O5&<* ,9063�,9&/3 ),*.7I)+&<O?7I)+).76,�DE3<YVAU(5, & A(0C*@&LAU(+3�)�I.&LO�0'3�&8Q %'& &'(+3@& 09>�3,G+*@&d79ONs¢3,G1&9,G).*,(KA,909A?AU(53�2-,<7I)4270'3+3<YEB;27) & AU(+-7)+24G+-7&zG+7I) & 3u763KO�*@&<O+(53+O;763*)uI;763+ONB;24O5) & B;2C) & &)*,*+09*MsA,/0C*,*@&9,G)42-063 ,d79G;7�sI�2:--27)+2-&)3T79*@&'O�&<3@24*.78I+--&8YE79G+G+*@0CG+*+247I)4&�)40�) & &'G1&<*@,9&/2:6'&)Og*@243,DE3)Q %'& &oO�&<3@24*,79I�24-727)P/�09> & 245 & -:/X3,(+*M682:6879I+-7&

w �

Page 142: Practical Architectures for Survivable Systems and Networks (Phase

B;24*@&<-7&<3,3�&/3V6 2:*+0'3KA &/3 ),3 ) & 7I)<,<763h79-43@0v>@(�3�,/)+2-0'3�3�)�763+ObsZ79-70'3�&�2-3 )+24A(&<3 08>,)*+243@243�2:3763O24AcG.0C*�)�763*)&21K79AcG+-7&�09>;) & & 35&9&<O )+0 2-3*)4&)5C*.7I)+&j763+OJ,/0 0C*HO�2-3+7I)4&() & &j*@&<\E(�24*@&<A(&93*).3U>N09*U3+&/,<(+*@27)P/CYS*+&)--2479I�24-727)P/9Y763+O"G.&)*H>N0C*HAg7I3�,9&�>N0C*<) & &c3H/b3�)4&<Ac3U7I3+OB3�&G)PB09*,DE3�2-3O) & &g-=78*,5'&UB & &/3D,9063K>@*+0'3*)+&<O�B;2C) & ) & &l>@(+-4-*.7I3+5'&�09>$79OK66&<*,3@27)+2-&<3;3�0I)4&<OK2-3�) & 243'*@&<G10C*@)<Q�]¢> ) & &3@).7I)4&)Ok*@&<\E(�24*@&<A(&93*).3u763KOK) & &�&93+3H(�2-3K5?3M/N3�)4&)A79*@, & 27)+&9,/),(+*+&)3vO�0 3�06)g763*)42-,/24G;7F)4&L) & 0C3@& 3�&/&<O+3?>@*+0CA ) & & 0C( ).3+&G)dYu79O�&)\E(;7I)4&k3.7I)+243M>¥76,/)+2-0'3H09>�) & &*+&)\E(�24*@&<A(&93*).3'B;24-:-_I1&J(�3;7I)@)�76273;79I+-7&9Q

��� � ���� �� � ��� � � ���� ��� �� � � �

% 0�BL79*HO�0C(K*^3�)�7I)+&<O�5'0V79-609>bO�&)66&<--09G�2-3+5z763+O<,/0'3��;5C(K*+2-3K5 & 245 & -0/W3H(+*H68206978I+--&�3M/N3�)4&)A?3�763+O 3�&/)PB�0C*HDb3)Y7">@(�3KO;79A(&93*)�79-�, & 79-:--&93K5'& 2:3 )40 ��� � ����� ����� ���#� � �K)�79DI&�79OK68763*)�7956& 09>�) & &n3@),*,(�,G).(+*@2-3+5�GK*+2-35,924GK--&<3{ $8&9,/)+2-0'31/NQ0����763KOe79*@, & 27)+&9,G).(+*,79- 3@),*,(�,G).(+*@&<3x{ $ &/,/)4270'37/NQ��9�LO�243@,<(+3H3+&<Oe79I10�66&9Q%'& 2:3^3@&9,G)42-063�,/0'3+3+2:O�&<*H3�3@0CA(&�*+&<GK*+&<3@&93*)�7F)42:66&�)P/bG1&<3�08>+79*@, & 27)+&9,G).(+*@&<3<YwB;27) & G;78*@)427,<(+-479*!&)A?G & 793+2:3

0'3~3@&<--&/,/)+2:6'&[s ),*,(+3�)PB0C*�) & 273�&<3H3e78*+, & 2C)4&9,G).(+*@&<3�) & 7I) 273 & &<*@&93*).-0/ 3,7I)42:3H>�/ Ag763V/�09><) & &�3�).*H(�,/),(+*+273+5G+*@2-3�,/24G+-7&<3<Q�m�0I)4&�) & 7I) ) & &fA 0CI524--&[sA,/0NO�&�G;78*.79O�2:5CA { $8&9,/)+2-0'3�/NQ � �^763KO>) & &LAU(+-7)+24-7&)6'&)-0s¢3,(+*M6 206879I�24-727)P/G;79*,79O�2:5CA#,d7I3xI1&�,/0CA?G+7I)42:I+-:/ 24AcG+--&)A &/3 ).79I+-7&$B;27) & 2-3�7z3@2-3+59--&S79*+, & 27)4&/,/),(+*+&Tp 763+O>273+O�&/&<Ox3 & 0C(+-:OI1&9Y�,/0'3+3+2:O�&<*@2-3+5�) & &J*.78A?G;7I3 )�G.0CGK(+-=79*@27)P/g763+O &/3�0C*,A(0C(+3o78OK68763*)�795'&)3 09>�A 0CI524--&M,90bO�&8Q �M0rB&26'&<*)Y) & & &21 2:3@)4&/3�,9& 09>'A(0CI�24-7&�,90bO�&?>N09*+,9&)3x(+3 )40 ,90'3K>@*@0'3*)xGK*+0CI+-7&<Ac3 ) & 7I)�06) & &<*HB;2:3+& & 7d6'&v-:(+*,DI&<OD273) & &�3 & 79O�0rBo3o>N0C*'A?763V/v/'&<79*,3)Q

£&/,d79(+3@&�AU(+-C)424-7&)66&<-u3H/b3@)+&<Ac3k78*+&�--&)3,3 ,)--0C3@&<-:/ 79-:--2-&)O�B;2C) & B & 7I)�243�,/0CA?A(&<*@,92479-4-0/�7d697I24-=78I+--&)40bO;7d/CYo7I3+O I1&9,<79(+3+& 0C(+*cAU(+-7)+24-7&)6'&)- ,90'35,9&<G )jO+*.7dBo3 & &d7d6824-0/�063 3+273+5C-7&2sP-7&)66&<- ,909A?G10'3�&/3 ),3<Y ) & &3+273+5C-7&2sP-7&)66&<-!,/0'3�,9&)G5)�243 ,9063+3+2:O�&<*@&<O �+*,3@)<Q���0rB&26'&)*<Y�*@&d79-7243�)42-,WAU(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+&F79*+, & 2C)4&/,/).(K*+&<3z79*@&>N&d783+24IK--&9YK5'2:66&93�7c-727)@).--&�,90CAcA(0'3j3+&/3+3+& 2-3�79G+GK*+0V76, & 2-3+5 3�0'35,90'3V6'&/3*)42-063;79-^79*+, & 27)4&/,/),(+*+&)3<Q

� ������� � ( � 1��'- � ( � � � � "I �!-e1 " - � �%1 �

� & ,90'3+3@24O�&)*�3�&[1 )�) & &j*+&)-=7I)+2:66&<-:/h3@24AcG+--&)*�,<793+& 09>M,/0'3V6'&93*)+2-0'3;78-�3+273+5C--&[sP-7&)6'&)-f3M/b3@)4&)A?3c763KO 3�&/)MsB�0C*,DE3<Q � &U7F)+)4&)A?G ) )40?O�& ��3�&�G+*+&/,92:3+&<-0/aB & 2-, & ,/0CA?G10'3�&/3*).3 09>�7g3@),*,(�,G).(+*,79-T79*@, & 27)+&9,G).(+*@&UAU(+3�)I1& ).*,(K3@)PB�0C*@) & /~B;2C) & *+&)3,G1&9,G)K)+0 &d76, & 09><) & &�6879*@2-0C(K3vO�24A(&93K3+2-063+3�09><).*H(+3@)PB�0C*�) & 273�&<3H3jp >N09*&21K79AcG+-7&9Y�273 )+&<5C*@27)P/9Y5,9063��;O�&/3 )+2=79-727)P/9YKG+*@&)6'&/3*)42-063 09>^O�&/3�2=79- 09>^3+&<*M682-,9&�763KOK0I) & &)*z783,G1&9,/),3;09>�7r68762:-0s79I�2:--2C)P/CY+5C(+79*.763*)+&9&<OeG.&)*H>N0C*HAg7635,9&9Y�763KOe*+&)--2479I�24-727)P/9Q % 79I+-7& /NQ��l3,(+AcA?79*+2 � &<3o3@0CA & 09> ) & &�G+*+2:Ag78*H/79*@, & 27)+&9,/),(+*.78- 3�&9&)O+3�) & 7I)M,d763K,9063 ),*+2:I+(5)4&<)40 0r6'&)*.79-:- 3,(+*M682:6879I�2:--27)P/9Y�2-3a*@&<3,G10'3+3@&�)+0() & &<24O�&/3 )+2�� &)O--2:A 2C)�7I)+2-0'3K3 09> % 79I+--&'/NQ0�CQ %'& *@0C(+5 & 0C(5) % 79I+-7&�/NQ �NY 2C) 2:3 &26 2:O�&93*) ) & 7I)�) & &)*+&�2:3F7gG1&<*M69783+2:66&�3�&/&<O>N0C*�5'080NO ,<*M/NG )40C5C*,79G & /CY$IE/�B & 27, & 2:3�2:A?G+-72-&)O�3@).*@0'3+5�78-45'0C*@27) & A?3zB & 0C3+& 24AcG+--&)A &/3*)�7I)+2-0'3+37I3+O3H/b3�)4&<A &)AUI.&)O+O�273+5C3o79*@&�GK*+0CG1&<*H-:/�&/3�,d78G+3,(+-47I)4&)O_Y 3�0'3K3,(+IV6'&)*@)+24I+-7&9Y )�79AcG1&<*,GK*+0809>ZY+763KOk*@&<--2479I+-7&9Q

� ������� � ��� - � � 1 1 �B+�� � � �� � � �r- � / �!- � � � � � �S1 � � � � � -0/ ( � - � ��1 � �

]A3B,/0'3+3@24O�&)*+2-3K5 ) & &g7I)@)�76273+A(&93*) 09>'3H/b3�)4&<A�s�Y 3�&/)PB�0C*HDVs.Y�763+O &93*)4&)*,G+*@243@&2s¢B;2:O�&gAx(+-7)+24--&26'&)-�3,(+*M6 206Vs79I�2:--2C)P/j{N2-3�,)-4(+O�273+5J79GKG+*+0CGK*+2=7F)4& 0���$¤Y&0�� ]�Y�0�� � �$B;2C) & 0C( )�AU(+-7)+24-7&)6'&)-0s¢3+&9,)(+*+& &/3+ONs¢(+3+&)*S3M/b3@)4&)A?3)YB�&XO+*,7dB & &<7r682:-:/�063kG;783@)'B�0C*,Da7I)�$Nyu]F}|�9�4/bY��K�r���^763+OL0'3+560'2-3+5�B�0C*,Dv7I)umWy �~{ &8Q|5KQ:Y^} � � �����[Q

%'& &'I;783+2-,L3@).*,7I)4&)59/�243 ,/0'3�,9&)G5).(+79-4-0/x3@24AcG+--&8Q^] )�A(24*H*+0C*H3�3@0CA(& 09> ) & &&d79*H-:/�B0C*HD>0'3�Ax(+-7)+24--&26'&)-0s3+&/,<(+*@&X3M/b3@)4&)A?3)Y;B;27) & 3+&26'&)*.79- >@(�3+O+79A &/3*)�79-_O52:i.&<*+&/3�,9&)3<�

w ��

Page 143: Practical Architectures for Survivable Systems and Networks (Phase

��������� � I� �a�"����������� �"!��"����u�����n�()+*�,.-�/�0213,�4�5202/"6 7M,9/�:;�<>02/"6 @{13,+BKC�:�,9/�024�5G0?/�6 DTE�4�0G524IHK025G0?/�6 JF:5G024IHK025G0?/�6`a(��M��z y j�u y ��!�'I� ����$%� ��������_I(Md �~�M�M��("(b�8&�'��"��&N��(�^ �������M�"'���������� y &�'=(R�"��!��8�������m l9d����������L�M������&�' �M����I�"&�sN�"�������L� ��!I�����M'����L�M������&�'�d (U&N!��"�M��(�d �"��nI!�'=n���'��M��d�8&InI��d�����&>X�(��M��( ��'�����s��"�Q�R�F(�������(�d �"��!=(R�"��n\���>�"��(�d (U�I(U���M$ �"�M�����������

�N�M�M&�!�'��"�����������R� sN&&n[�M'=�8�"��������&�' V2��!����b��&N�����"��'��8� �����"nIXo���"�u��8�RXY&��"_��'�s �Y�M�U���������"&��"&�M&��L(Md �Y�M�U�����b���"&���&I�M&��L(Md g�&��"�8����&N��!�(U� g�&N���M� �"&���!=(R���'�n\���"&��"&�M&��L( (�&�!�'�n\�M$A�3��n�nI��'�sN( (�&�!�'�nF��$A�3��n�n���'�s�( nI�8V?��'�(U����� nI�MV?�M'�(����N�

sN&&n[�M'=�8�"��������&�'�d sN&&n[�M'=�8�"��������&�' ����&���&I�8&N��(�d ���"&��"&�M&��L(Md����$c�3�M�"����&&�p�'�s �M$A�3��n�nI��'�sN( �M${�=��n�nI��'�sN(

y ����I�"&�s���������� ����$c�3�M�"���"&�&�V���'�n ��&���!�(U�a����s�&N��������$c( �a��nI�����>�"��n �.��!�(U�RXY&�������} V?&��a��'�����s��"�Q�R�Nd '�&�'�(�!�������U�"������� ��'�n[����&���&I�8&N��(�d ������nIXo���"��d (�&�!����8��(Md��!I�"���M'����L�M������&�'�d ��$c�����M$c�M'��"������&�'�( '�&�'�(�!�������U�"������� (U��'�(U�������x` l9 (�!��=������$c�=&�(U��n�M'��M����I�"��&N'=� ��$c�����M$c�M'��"������&�'�( �8�"������&%�=&N���L�8� � �M�"�"&��o�8&��"�"��� �"��&N'��!I�"���M'����L�M������&�' lI�=&&�V?����&&�p='�s�d m '��8� ����$%�x�M����I�"&�� �������M�"'���������� �~��(U���"����!I����n(U!��=(U�I(U���M$S( �"�M�����]�T���������M'��"��&N'�d �=��(���nF��&�_N�M'�(�d V2��!����U� ��&N�����"��'N� �8&N'�(���(U����'��8�Nd} �� s��d�Xb����� �M����3&%��&�_N�M'�(�d ��'�(U&N$c�q����(���( ��!I�"���M'����L�M������&�' �"��nI!�'=n���'��M�(R�"��&N'�sS�8�"������&�� ����$c�3�M�"����&&�p�'�s ����&N$%�M���"����( (U�����N�M��( ��'[�����"n�XY������+�"!�(U����n\��������( �.�"!�(R�"��n\�������[��& �.�"!�(R�"��n[���>�"�\��& �a��nI�����>�"��n l���QVW�P��������_��'�s�d��'�n\�"��(�&�!����8� !=(U���"(b��'�n[(��M�"�����"(�d !=(U���"(b��'�n[(��M�"�����"(�d �8&�'�'����8����&�'�(�d V2��!��Q�b�"&����M����'��M��d��'�����s��"�Q�R� ��'�����s��"�Q�R�F�N(o��' sN&&n[�M'=�8�"��������&�' �������M�"'���������� nI��nI�����>�"��n

!=(U��� m lI( } ���=&>�N��� ���"!�(R�"��n[���>�"��( �8�����8!����"(l�M�"�����"( } p=���Nd lI!��=������&���(����M!��"�Q�R�Nd lI!��=������&���(����M!��"�Q�R�Nd g����"�"&��"��n y &�'=(R�"��!��8�������VW����d=�N������d sN&&n[�M'=�8�"��������&�'�d sN&&n[�M'=�8�"��������&�'�d p����x(��M�"�����"(�d �"��nI!�'=n���'��M��d�8��$c����� dI�8���� � ��!I�����M'����L�M������&�'�d ��!I�����M'����L�M������&�'�d ��&N��!�(U� (��M��V2��������_��'�s

�3�8�����������"&���&I�M&��L(Md �3�8�����������"&���&I�M&��L( V2��!����U� ��&N�����"��'N� ���"&��"&�M&��L(����$c�3�M�"����&&�p�'�s ����&���&I�8&N��(

ef�������3�M��( lI�=&&�V?����&&�p='�s lI�M'�(�������� ��!I�"���M'����L�M������&�'�d �b&N��!�(U� m l�(Md��'�nZv����"�MXo�����L( �3&����L�8����( ���"!�(R�"��n[���>�"��( Xb�������3�M��(Md

p��"�MXo������(g�&�'�����&N����'�s=d ����$c�3�M�"���"&�&�p�'�s=d � 'IV?&����8��$c�M'��b&�V y &�'�����'!��Q�R�F&�V l���QV2��������_��'�s=d��'������I(���(�d '�&�'����=��("(������������R��d �������>���8�[�8&�'=�8�M�"'�( (U������L�8��dI(U���"&�'�s V2��!��Q�b�"&����M����'��M��d����(U�3&�'�(�� �]�N&��Ln���'=�8�t&�V } $A!�����(��M'�(���������� �8&�'�'����8���������R��d �8&&N�"nI��'�������nF'��8���

&>�N�M�"�������8����&�'�( n��>�"�%��'��&�������n�� (U���QVW�PnI�L��s�'�&N(���( XY&��"_S$c��'���sN�M$c�M'��

w �

Page 144: Practical Architectures for Survivable Systems and Networks (Phase

2 %'& & 0r6'&)*.79-:-'3H/b3@)+&<A 79*+, & 27)4&/,/),(+*+&�Ag78D6&<3cO�2:3@)4273�,/)+2-0'3K3l79A 063+5 ) & &a6879*+270C(+3lO�24A(&93K3+2-063+3�09>),*,(+3�)PB09*@) & 2-3�&)3,33506)4&)O 2-3 $ &/,/)4270'3 /bQ �KQ0�CYVB;27) & *@&<3,G1&9,G))+0�273 )+&<5C*@27)P/9Y8,/0'3��;O5&93*)42479--2C)P/CYEG+*+&26'&/3Ns)+2-0'3 08>$O�&/3�2=78-!09>T3@&<*M6 27,9&8Y 06) & &)*u793,G1&9,G).3M09>T7d68762:-=79I�2:--2C)P/CYE763+O�5C(;78*.763*)4&/&<O�G.&)*H>N0C*HAg7I3�,9&8Q

2 %'& &�0r6'&<*,79-4-�3H/b3@)+&<A�79*+, & 2C)4&/,/).(K*+&�7I)@)4&)A?G5),3�)+0jA 273�24A(2 � & ) & &�&[18)4&93*)�)+0gB & 2-, & ) & &x6879*@2-0C(+33H(+I+3M/N3�)4&)A?3UAx(+3@)XI.&cAU(+-C)42:--&)66&<- ),*,(+3�)PB0C*�) & / {@B;27) & *@&<3,G1&9,G)>)+0 &d7I, & 3,G1&9,/2�� ,cO�24A(&93K3+2-063��2YG+79*@)+2-,<(K-=79*H-:/�IV/�7d660'24O�273+5 ) & &�3�&/&<O�>N0C*�),*,(+3�)PB09*@) & 2-3�&)3,3�2-3B&93+ONs¢(+3+&)*�3H/b3@)+&<Ac3 0�66&<*xB & 2-, &) & &<*@& 243 350�,90'3*).*@0C-�0C* 350�&21NG.&/,/).7I)4270'3 09>�AU(+-7)+24-7&)6'&)-8),*,(+3�)PB09*@) & 2-3�&)3,3<YN763+O�IV/�,/0'3�,/&93*).*,7I)4273+5) & &;&93K>N09*+,9&)A &/3*)09>�AU(+-C)424-7&)66&<- ),*,(+3�)PB09*@) & 2-3�&)3,3fB & &<*+&�27) 2:3f78I+3+0C-:(5)4&)-:/>&<3,3@&93*)42479- Q %'& &zI+793+27,78*+, & 2C)4&9,G).(+*@&h793,3H(+A &)3 ) & 7I)�A(0C3@)L08>�) & &O&93+ONs¢(+3+&)*a3H/b3@)+&<Ac3 0CG1&<*,7I)4&h7I)�7�3@2-3+5C-7&�G;762:*�09>0 � $K�40�� ]X-7&)66&<-43l7F)l7 )424A(&9YT763+O ) & 7F)�A 093@) 09>;) & & 0���$ &/3K>N0C*@,9&<A(&93*) 2:3�2-3D) & &j3+&<*M6'&)*,3p B;2C) & G.093,3+2:I+-:/ 3+0CA(& ).*,(K3@)PB�0C*@) & / {@I+(5)(3�06) 0���$J),*,(+3�)PB09*@) & /K�c-70 ,<79-�3@&<*H66&<* 2-3*)4&)*H>¥76,/&3@09> )PBL79*+&x763+OeG10C3H3+24IK-:/ & 79*HOKBL79*+&�,908s¢G+*+08,9&)3,3+09*,3<Y�>N0C*M&21K79AcG+--&8Y�793M0C(5),I.0C79*,O ,<*H/bG5)+0C5C*,79G & 27,&/3+5'273�&<3)Q

2 %'& &>,9063�,9&)G5) 09>TA 0'350C--2C) & 27,JAU(+-7)+24-7&)6'&)- D6&)*+3�&)-43F7I3+O % q�£L3J783M) & &xI;783+2-,�I+(�2:-4O�273+5cI+--08,�DE3�2:37d660'24O�&)O_Y 2-3K3@)4&<79O ,/0'3+3@24O�&)*+2-3K5cA(0C3�).-:/vAU(+-7)+24G+-7&W3@2-3+5C-7&2s¢--&)66&<- 3M/N3�)4&)A?3z763+O ,90'3�,/&93*).*,7I)4273+5(0'37U>N&2B 3+&)--&/,/)4&)O ),*,(+3�)PB0C*�) & /a3+&)*H66&<*,3W763+OK06) & &<* ,<*@27)+2-,d78-!,90CAcG10'3�&93*),3<Q

2�� &935&<*.78--2 � &<O�O�&<G1&93KO�&93�,/&�243M&21NG+-72-,92C).-0/j76,/,90CAcA 0bO;7I)+&<O_Y 0'3 0'3�& & 763+O�7d660'24O�273+5 ) & &X3+&<*@2-0C(K3GK*.76,G)42-,<79-_-724A(27)�7F)42-063+3 09> & 7r68273+5�)40(&93K>N0C*@,9&3@),*+27,/)oAU(+-C)42:--&)66&<-¤G;79*@)+2=79- 0C*,O�&)*+273+5C3'--08,d78-4-:/9YK7I3+O063 ) & &�06) & &<* & 763+O�79-:--0rB;2-3+5�>N0C*M).*H(+3@)PB�0C*@) & /nA(&9, & 7635243,Ac3�)+0gA(&<O�247I)4&X79A(0'3+5?G.06)+&93*)42479-4-0/-7&<3H3 ).*,(K3@)PB�0C*@) & /K,/0CA?G10'3�&/3*).3<Q

2 � -4-f3+&93K3+27)+2:66&K273K>N0C*HAg7I)+2-0'3�763+O�A &)O�2=7 &/3*)427)+2-&)3�{¥O;7I).7KY�G+*+095C*.79Ac3<Y 3�&G)PB09*,D , & 76353�&<-:3<Y�7I3+O0I) & &)*'O�& � 3+79I+--&J*@&<3@0C(+*+,/&<3.�;3�&/,9&)3,3.78*H/a>N0C*�3M/N3�)4&)A 3,(+*M6 206879I�24-727)P/(,909(+-4OaG106)4&/3 )+2=79-:-:/ & 7d6'&X79GNsGK*+0CG+*@2=7I)+& 0�� � -479I1&<-43c{N2-3�,/0C*,G10C*,7I)4273+5v6'&/,/)409*+&<O 0���$¤Y 0�� ]�YW0�� � 3H(+I+-=78I.&)-43<0'3+-0/nB & &<*@&78G+G+*+09G+*+247I)4&d�2YV5'206 273+5X79-4-;G106)4&/3*)42=78-4-:/�,<*@27)+2-,d78-;3,(+I+3M/b3@)4&)A?3&21NG+--27,92C)fA(&d783,(+*@&<308> ).*H(+3@)PB�0C*�) & 2¦s35&<3,3)Q � 3E/n3,(+I+3M/b3@)4&)A 0C* ,/0CA?G10'3�&/3*)<3�06)�&[1KGK--2-,/27),-:/a-=78I.&)--&<O 2:3J793H3,(+A(&<O )40jI1&�A(2-3�2:Ag79-:-:/),*,(+3�)PB09*@) & / {N) & 7I)<2:3<Y^G.06)+&93*)42479-4-0/CY!,/0CAcG+--&G)4&<-0/n(�3*),*,(+3�)PB0C*�) & /"(�3+--&)3,33,G1&9,/2�� ,(,d7d66&d7I),3U79*@&273�,<-:(+O�&)O��2Q � -7)4&)*+3;7F)42:66&<-0/CY ) & &--&26'&<-:3oAg7d/vI1&�)�79DI&93 ,d79*@& 08>�2:A?G+-72-,/27).-0/�2-3 ) & &O�&<3@245'3_Q

� 2:6'&/3 ) & 243 )P/bG.&�09>`79*@, & 27)+&9,/),(+*.78-¤3�).*,(5,/).(K*+&9YK7X*@&<-=7F)42:66&<-0/�3+2:A?G+-7&;2-3K>N0C*HAg78-;763;79-0/b3+243 ,d7I3vO�&/)+&<*ZsA(2-3�&'B & &G) & &)*27) 2:3f7F)�79-:-;--2:D6&<-0/>) & 7I) ) & &z79*+, & 27)4&/,/),(+*+&�,d763 &93K>N0C*@,9&M) & &uO�&<3@24*@&<OvG;78*@)42479-�0C*HO�&<*@2-3+593OK/83;79A(2-,<79-4-0/CQ`]A3�06) & &<*$B�0C*HO+3<YE79*@&) & &<*+&o7I3E/X5C*@0C3,3T682-09-=7I)+2-0'3+3�09>+0�� � O5&<G1&93+O�&/3�,9&;0'3�-7&<3H3�).*H(+3@)MsB�0C*@) & /l3H(+I+3M/N3�)4&)A?3 �e]¢>_3+0KY8,<763c5'&93�&)*.79-72 � &<OlO�&<G1&93KO�&93�,/& 273c3@0CA(&oBL7d/c79O�&)\b(+7I)4&)-:/�0r6'&)*+,/0CA &;) & &G106)4&/3 )+2=79-�682-0C-47I)4270'3+3 � ¡ 09*,A?79-�A &G) & 0bO+3U78*+& 3506)U*@&<\E(�24*@&<O 273B) & &?I;793@2-,g3�)�7956&<3�09>oO5& � 3�273+5 ) & &79*@, & 27)+&9,/),(+*+&8Y�79-7) & 0C(+5 & ) & &2/ ,90C(K-4OjI1&J(+3+&2>@(+- -=7I)+&<* 063K273aG+*+0r6824O�273+5�24AcG+-7&<A(&93*)�7I)+2-0'3?793H3,(+*,763�,9&8Q

�W6'&)*.79-:- Y'B&�3 & 0C(+-:O 3506)L&21NG1&9,/)L) & 7I)dYz79G;78*@)j>@*+09A 0���$�{@B & 27, & Ag7d/ I1&n>@(�3+O+79A &/3*)�79- )+0,9&)*@).762-3?79G+G+-72-,<7I)4270'3+3��[Y6) & &<*+&oB�0C(+-4OcI1&W7*+2:5'0C*+09(+3 &93K>N09*+,9&)A &/3*) 09>¤3@),*+2-,G)LG+79*@)+2=79-�09*,O�&)*+2-3K5X78A 0'3K5) & & 06) & &<*'7I)@).*@24I+(5)+&<3 08>V0 � � { 3;79A(&<-0/CY.0�� ]L7I3+O 0�� � � ) & *+09(+5 & 0C( ) ) & & &93*)42:*+& &/3 )+&<*HG+*+2:3+&9Y�7I3+O*.7F) & &)*>) & 7F)�A &/, & 763�2:3,Ac3�2-3V660CD 2-3+5�5'&/3�&<*,79--2 � &)O O�&<G1&93KO�&93�,/& ,<763 ,909A?G1&93+3,7I)4&v>N09*xB & 7I)UB�0C(+-:O06) & &<*MB;243+&I1&J6 270C-=7F)42-063+309>�G;79*�)42479-!0C*HO�&<*@2-3+5+Q

w �

Page 145: Practical Architectures for Survivable Systems and Networks (Phase

� ������� � � ��& � � 1 � + � � -e1� � ( �t( ��1��'- �� 3�& 09> 09(+*$A(0C3@)�>@(�3+O;78A &/3 ).79-52:3,3H(�&<3 ,/0'3�,/&<*+3K3 ) & & &[18)4&93*) )+0WB & 2-, & ),*,(+3�)PB09*@) & /�3M/b3@)4&)A?3 ,<763�I1&O�&26'&<-70CG1&<O�O�&<3HG�27)+&<) & &G+*+&)3+&/3�,9&�09>�&/3+ONs¢(+3+&)*u3M/b3@)4&)A?3M09>^6879*H/82-3K5cO5&<5C*@&9&<3;09>�(�3*).*H(+3@)PB�0C*�) & 273�&<3H3<Q%'& 2:3�243,3H(�& 243X6'&<*M/ 24AcG10C*@).763*)�2-3�3@2-3+59--&2s¢--&26'&<-S3H/b3�)4&<Ac3k{ $ &/,/)+2-0'3�/NQ|�KQ0���2Y�763KOH2:3�&)66&93�A 09*+&�2:AlsG10C*@).763*) 2-3 ) & &�,90'3*)4&[18);09>`AU(+-C)424-7&)66&<-�3H/b3@)+&<Ac3�B;27) & A 273�24A(2 � &<O�).*H(+3@)PB�0C*�) & 273�&<3H3�{ $ &/,/)4270'3"/NQ|�KQ �C�2Q%'& &�>N0C-:--0rB;2-3K5W\E(�&<3�)4270'3+3�*+&)-=7I)+&�)+0�&93+ONs¢(+3+&)*�76,9,/&<3H3 )+0�3�&/)PB�0C*HD6&<O?O�243�).*@24I+(5)+&<O�&/3V6 2:*+0'3KA &/3 ),3 ) & 7F)79*@& 273*)4&93KO�&<OL)40lI1& & 245 & -0/g3H(+*H68206978I+--&8�

2 � & 7I)�20>5) & &0CG1&<*,7I)4273+5u3H/b3@)+&<A 3@&9,)(+*+2C)P/�063U763�&/3+ONs¢(+3+&)*$3H/b3�)4&<AE243�3�06)�).*H(+3@)PB�0C*@) & /a{ 273X3@0CA(&G+79*@)+2-,<(K-=79*�*+&)3,G1&9,G).3�� �n]A3�) & 7I),d793@&9Y;7XAg793H\E(�&<*,79O�&<*0C*LA(243�)�79DI&93+-0/(),*,(+3�)4&)O�-7&<5'2C)42:Ag7I)+&'(+3+&)*A(245 & ) ,<*+&<7I)4& ,/0'3+3+2:O�&<*,79I+-7& & 7d6'08, 0'3 ) & 7I)�3H/b3@)+&<A�Q ¡ 09*�&21K79AcG+--&8Y 27)<243�3506)JB;243@& )+0k(K3+&c73H(+IV6'&)*@)42:I+--&�09G.&)*.7I)+2-3+5j3M/N3�)4&)A >N0C*F3@)+0C*+273+5a763V/ ,)*H/bG5)+0C5C*.78G & 2-,�DI&)/b3 &<3,3@&93*)42479- )40j-70 ,<79-T7I3+O35&/)PB�0C*,D 0CG1&<*,7I)4270'3+3<QTR�66&93�20> ) & &WDI&)/b3'79*@&z3�)40C*@&<O�0'3g7�3HAg78*@)Hs ,d79*HO 0C*�3@24A(24-=78*TO�&)6827,9&9Y�5�7dBo3273 ) & &�0CG.&)*.7I)+2-3+5�3M/b3@)4&)A 79*@&J--24DI&<-0/()+0�Ag78D6& ) & &�,<*H/bG5)+0C5C*,79G & 27, 24AcG+--&)A &/3*)�7I)+2-0'3+3S3,(KIE66&<*�)Hs2:I+--& 0C* )40cAg79DI&�) & &�(�3�&/3�,<*M/NG )4&<O 2-3K>N0C*HAg7F)42-063j76,9,/&<3H3+24IK--&9Q %'& (+3<Y ) & &3M/N3�)4&)A 78*+, & 2C)4&9,G).(+*@&Ax(+3@)�&21NG+--27,92C).-:/J793,3H(+A &�) & &f-=76,�D<09> ),*,(+3�)PB0C*�) & 273�&<3H3<YCB & &)*+&26'&<* ) & 7I) 243T7zG.06)+&93*)42479-EG+*+09I+--&)AkQ]A3�) & & ,d793@& 09>JAU(K-7)42:--&26'&<- 09G.&)*.7I)+2-0'3+3)Y 27)cA(245 & )?I.&kO�&9&)A &)O~76,9,/&<G5).79I+-7& )40 793,3H(+A &K) & 7F)) & &J(+3@&<*M09>T7�G106)4&/3*)42=78-4-:/c(�3*),*,(+3�)PB0C*�) & /K&93+ObsP(+3@&<*u3H/b3@)+&<A ,909(+-4OL0CG1&<*,7I)4&�7I)u7�G1&<*,A(243H3+2:I+--&3@&9,)*+&9,2/e-7&)66&<-^3+&<-7&9,G)4&<O�IV/K27),3U{¥79G+G;78*+&93*)��u(+3@&<*up 2:>$(+3+&)*J79(5) & &93*)427,d7I)+2-0'3K,d7I3nI.&XO�0'3�& 2-3e7350'3+3,(KIE66&<*�)424IK--&WBL7d/ ) & 7I)�GK*+0r6824O�&)3o79O�&<\E(;7F)4& ),*,(+3�)PB0C*�) & 273�&<3H3<Y�763KO�2:>!) & &<*@& 243f3+0CA(&W3@0C*@)09>),*,(+3�)4&)OkG;7F) & )40�) & &O�&<3@24*+&)OL0CG.&)*.7I)+2-3+5�3M/b3@)4&)A { 273�,<-:(+O�2-3K5�2-3*)4&)5C*+2C)P/ , & &9,�DE3�)+0(&/3+3,(K*+&�) & 7F)) & &09G.&)*.7I)+2-3+5u3H/b3@)+&<A & 79O�3�0I)TI1&9&93x3,(+Ib§@&/,/)+&<O�)40 ).79AcG.&)*+2-3K5E�2Q ¡ 0C*�&21K79AcG+--&8YC7z-7&)66&<-508>;(+3+&)*78(5) & &/3*)42-,/27)P/ ,90C(+-:O�I.&lG+*@0r6 2:O�&<O�IV/�G & /b3+27,d79- &/3�,<-70C3,(K*+&<3X763+O�G1&<*H3+0'3;78-T*+&/,90C5'3527)4270'3_Y!09*JIE/7I3�0C(5)MsA09>=s¢I;763+OXI�2-0CA(&/),*+27, )+&9, & 3524\E(�& 0C*$7�).*H(+3@)+&<ONs¢G;7I) & ,<*H/bG5)+0C5C*,79G & 27,�79(5) & &93*)+2-,d7F)42-063XB;27) &O5&<O�27,d7I)+&<O 350'3*)�79AcG.&)*.79IK--& & 79*HOKB�78*+&9Q�]¢> ) & 7I)L793H3,(+AcG5)4270'3(243 3�06)_§H(+3@)+2���78I+--&8Y ) & &WG+79*@)+2-,<(K-=79*(K3+&<* 09>.) & 7F) &93+ONs¢(+3+&)*L3M/N3�)4&)A�B0C(K-4O & 7d6'&;)40 0CG.&)*.7I)+&u7I)S763c(�3�,<-4793,3@2�� &)Og-7&)6'&)- Q�]A3g763V/ ,<793+&8Y2C)SAU(+3@)fI1&z*@&d79-72 � &)O ) & 7I) & 245 & sA&/3+Ov79( ) & &/3 )+2-,<7I)4270'3?3H(�, & 793S(�3K>N0C*H5'&d78I+--&z763+O 3�0'3+*@&<G+-47r/C79I+-7&I52-0CA(&/),*+2-,)3oAg7d/a3@)+24-:-^I1&U7F)+)�7I,�D6&<O�IV/ ,90CAcG+*@0CA 2:3+&)3u>@*@0CA�B;27) & 2-3e763+OnI1&<-70�BQu] )FAx(+3@)F79-43@0I1&�*+&)A &)AUI1&<*+&)O ) & 7I)Ax(+-7)+24--&26'&)-�3@&9,<(K*+27)P/nO�0 &)3<3�06)�79O+OK*+&<3H3<2-3*)4&)5C*+2C)P/ 2:3,3,(5&<3?{¥G;78*@)427,<(+-479*,-0/) & 0C3@& &/3�,909A?G;783,3+&)OeIV/jAU(K-7)42:--&26'&<-.2-3*)4&)5C*+2C)P/K�2Q

2 � & 7I) 2:> ) & &z79(5) & &93*)+2-,d7F)42-063(08>�(+3@&<*H3�0'3 ) & &�&/3+ONsP(K3+&<*S3H/b3�)4&<Ac3 243 3�06) ),*,(+3�)PB0C*�) & /�� %'& &93g7A?793H\b(5&<*.78O�&<*�,d7I3>,<*@&d7I)+&�,/0'3+3@24O�&)*.79I+-7& & 7d6'08,S>@*@0CA 7o--08,d79-8B0C*HDE3@)�7F)42-063_Y8G1&<*H3+0'3+79- ,90CAcG+(5)+&<*<Y09* 3�&/)PB�0C*HD ,90CAcG+(5)+&<*<Q � O+O�2C)4270'3;79-�79(5) & &93*)427,d7I)+2-0'3�I1&9,/0CA(&<3<&<3H3+&93*)+2=79-�I1&)>N0C*@&l763V/n>@(+*�) & &)*350'3+--08,d78-¤7I,9,9&)3,3;243fG.&)*,A(27)@)4&<O�Q�qL--&<79*,-0/CY82:>`(+3@&<*,3o78*+&J79-:--0rB�&<O )+0 & 7d6'&7U3@2-3+5C-7&z3@245'3bsA0'3�{ ) & 7F)2:3<Y 3�0l>@(+*�) & &)*z(+3@&<*W79(5) & &93*)427,d7I)+2-0'3�793;) & &2/�A 0r6'&>@(+*�) & &)*z78--0'3+5(2-3*)+0(35&/)PB�0C*,DI&<O�3H/b3�)4&<Ac3��[Y) & & &93KONsP(+3@&<*�3H/b3@)+&<Ac3e7I3+O 06) & &)*a3H/b3@)+&<Ac3e79-70'3+5D) & &nB�7d/ AU(K3@)�I.&�3H(+I+3�)�763*)42479-4-0/ A(0C*+&),*,(+3�)PB09*@) & /a3@0() & 7I);) & &�79( ) & &/3 )+2-,<7I)4270'3L,d763K27),3+&<-0>^I.&A(0C*+& ),*,(+3�)PB0C*�) & /CQ���0rB�&)6'&)*<Y�3+273+5C--&3@245'3bsA0'3�243v7h6'&<*M/ I;78O 24O�&<7 2:><09G.&)*.7I)+2-3+5"3H/b3@)+&<A 3@&9,)(+*+2C)P/~79-70'3+5 ) & &eBL7d/ 763KO &93+ONs¢(+3+&)*78(5) & &/3*)42-,<7I)4270'3"79*+&(3�06)�24AcG.&/,9,<79I+--&�) & *+0C(K5 & 0C(5)<Qj]A3D,d783+&<3�2-3hB & 2-, & ) & &(2-3*)4&)5C*+2C)P/O09> ) & &78(5) & &/3*)42-,<7I)4270'3�2:3�\E(�&<3�)42-063;79I+-7&9Y5) & &J3H/b3@)+&<A 78*+, & 2C)4&9,G).(+*@&AU(+3@) &21NG+--27,92C).-:/?793H3,(+A(& ) & &J-=76,�D08> ),*,(+3�)PB0C*�) & 273�&<3H3<Q]A3K) & &�,d793@&>09>TAU(+-7)+24-7&)6'&)- 0CG1&<*.7F)42-063+3<Y ) & &xG;79*�)427,<(+-479*'(+3+&)* 09>�) & 7I)�&93KONsP(+3@&<*F3M/b3@)4&)A B�0C(+-:O& 7r66&�)40 0CG1&<*,7I)4&l7I)�7I3h(53�,<-4793,3@2�� &)Oh-7&)66&<- Y 0C*�&<-:3+&�3,(KI+A 2C) )40�79( ) & &/3 )+2-,<7I)4270'3�IV/�7�).*H(+3@)+&<O

w �

Page 146: Practical Architectures for Survivable Systems and Networks (Phase

Ax(+-7)+24--&26'&)-�79(5) & &93*)427,d7I)+2-0'3"3+&<*M6'&)*�I.&2>N0C*+&j7I3E/h>@(+*�) & &)*>3�0'3K--08,d79-S76,/,9&<3H3�243XG.0C3H3+2:I+--&8Qk]¢>;) & &-70 ,<79-879(5) & &93*)427,d7I)+2-0'3�2:3 3�06) ).*H(+3@)PB�0C*�) & /�763+O�) & &S-70 ,<79-609G.&)*.7I)+2-3+5�3M/b3@)4&)A 243 3�0I) ).*,(K3@)PB�0C*@) & /9Y350?7I,9,9&)3,3;)40cAU(+-C)424-7&)66&<-�*@&<3@0C(+*+,/&<3u3 & 09(+-4O�I.&JG1&<*HA 2C)+)+&<O_Q

2 � & 7I) 20>�) & &3�&/)PB�0C*,D 273+53+09> )PBL79*+&0'3�) & &�&93+ObsP(+3@&<*�3H/b3�)4&<Ac3 243 3�06) ).*,(K3@)PB�0C*@) & /�� � 5V762-3�YI) & &3M/b3@)4&)A 763+OK3�&/)PB�0C*HDa79*+, & 2C)4&/,/).(K*+&<3uAU(+3�);&21NG+-72-,92C).-0/v793H3,(+A(&�) & &-476,�D�09>�).*H(+3@)PB�0C*@) & 2-35&<3,3)Q]A3() & &�,d793@& 09> Ax(+-7)+24--&26'&)- 0CG.&)*.7I)+2-0'3K3<Y83�0X>@(+*�) & &)*�76,/,9&)3,3�3 & 0C(+-:OvI.&uG1&<*,A(27)@)4&)O 2:>_763V/gAx(+-7)+20s-7&)66&<-�3+&9,)(+*+2C)P/ 2:3L*@&<\E(�24*@&<Oj7I,<*+093,3) & & 3�&G)PB09*,D�Y 0C* 2:>!) & & 2-3*)+&<5C*@27)P/ 09>!) & & 3�&G)PB09*,D6&)Oa*+&<A(06)+&&/3*)427)P/�,d763�3506)oI.&�793H3,(+*@&<O_Y 0C* 20>T7I3K&/3*)427)P/Vs 2-3Ns ) & &[sPA(24O+O+-7&F7I)@)�76,�D 243'G10C3,3@24I+-7&9Q

2 � & 7I) 20> ) & &�&93�,)*H/bG5)+2-0'3 0'3 ) & &�&/3+ONs¢(+3+&)*F3H/b3@)+&<Ac3�,d763eI.&XIE/bG;783,3+&)O 09* ,909A?G+*@0CA(243+&)O � ]A3) & 7I)�,d793@&9Y ,)*H/bG5)+0C5C*.78G & /�(+3@&<O >N0C* &935,<*H/bG5)+2-3+5�3�)40C*@&<OD273K>N0C*HAg7I)+2-0'3 ,<763 I1& ,/0CA?GK*+0CA(243@&<O_Y&/3�,<*M/bG5)4270'3�(+3+&)O�273 3�&/)PB�0C*HD8273+5O,d763�I1&�,909A?G+*@0CA(243+&)O_Y�D6&2/b3c(K3+&<O�>N0C*�273*)4&<59*+27)P/ , & &/,�D8273+5A?7d/vI1&3,G10 09>N&)O_Y;763KOe79( ) & &/3 )+2-,<7I)4270'3aD6&)/b3uAg7d/jI1&�,90wsA0CG5)+&<O_Q]A3 ) & &<,d793@&�09>�AU(+-C)42:--&)66&<-.0CG.&)*.7I)+2-0'3K3<Y�3�0�>@(+*�) & &)*u76,9,/&<3,3z3 & 09(+-4OaI1&�G1&<*HA 2C)+)+&<O_Q

2 � & 7I)�2:> ) & &>).*H(+3@)+&<OhG;7I) & )+0�) & &�&/3+ONs¢(+3+&)*J3H/b3@)+&<Ac3 ,<763�I.&�,/0CAcG+*+0CA(243@&<O � ]A3 ) & 7I)�,<793+&8Y�N15&)O G;783,3HB�0C*HO+3 ,<763 I1& ).*+20682=79-:-:/ ,d79G5),(+*+&)O_Y'79-C) & 09(+5 & 0'3�&[s )42:A &gG;793,3MB09*,O+3gB�0C(+-:O I1&L09>350n(+3+&h{¥793U-70'3+5�793�) & &2/�79*@&v--08,d79-:-:/�56&93�&)*.7I)+&<O�763+O 3506)�,9063�,<(+*H*+&/3 ),-:/�*+&<(K3.79I+-7&j7I)�0I) & &)*-70 ,<7I)4270'3+3.�2Q]A3 ) & &<,d793@&�09>�AU(+-C)42:--&)66&<-.0CG.&)*.7I)+2-0'3K3<Y�3�0�>@(+*�) & &)*u76,9,/&<3,3z3 & 09(+-4OaI1&�G1&<*HA 2C)+)+&<O_Q

%'& (+3<YzB&"79*+&n>¥7I,9&<O B;27) & &<3,3@&93*)42479- ).*,79O�&[sA09i¤3<Q�]¢> ) & &�-70 ,<79- &/3+ONsP(K3+&<*L0CG1&<*,7I)4273+5�3H/b3�)4&<Ac3763+OD) & &92:*�),*,(+3�)4&<O�G;7F) & 3�,<763�3�0I)�I.&�),*,(+3�)4&)O_Y ).*,(K3@)PB�0C*@) & 2-3�&)3,3�AU(K3@)�3�0I)�I.&v793,3H(+A &)O�763+OD) & &79*@, & 27)+&9,/),(+*+&AU(K3@) ).*,763+3M>N&<* ).*H(+3@)PB�0C*�) & 273�&<3H3M)+0c3@&<-7&9,/)+&<O�3+&)*H6'&)*,3�p B & &<*@&G.&)*,A(27)+)+&<O_Q$]¢> ) & &--08s,d78- 79(5) & &93*)427,d7I)+2-0'3 ,<763�3�0I)zI1& ).*H(+3@)+&<O_Y�),*,(+3�)PB09*@) & 2-3�&)3,3uAU(+3@)oI1& ).*,763+3M>N&<*,*@&<OL)40c79(5) & &93*)+2-,d7F)42-0633+&)*H66&<*,3)Qe]¢> ) & &g-70 ,<79- 3�&G)PB0C*HD 2-3+5n3@09> )PBL79*+&�,<763�3�0I)xI1& ),*,(+3�)4&<O�Y�) & &/3B).*H(+3@)PB�0C*�) & 273�&<3H3UAU(+3�)UI1&).*,763+3M>N&<*,*@&<O )40j3@&<-7&9,/)+&<OO3�&G)PB0C*HDe3@&<*H66&<*H3<Ql� 3 ) & &�06) & &<* & 7I3+O_Y 2:> ,/&<*�)�76273n3+&)*H6'&)*,3X79*+&>3�06)J3H(���s,927&93*).-0/ ).*H(+3@)PB�0C*@) & /eB;27) & *@&<3,G1&9,G) )40 ,9&<*�)�76273eO�2:A &/3+3+270'3+3)Y ) & &93�785V762-3L).*H(+3@)PB�0C*�) & 273�&<3H3 2-3K) & 0C3@&O�2:A &/3+3+270'3+3'AU(+3�)oI.&�),*.763+3M>N&<*H*+&<OK)40l3+&)*H66&<*,3M) & 7F)u79*+&A(0C*+& ),*,(+3�)PB09*@) & /9Q

]¢>AU(+-C)42:--&)66&<-o3+&/,<(+*@27)P/�243()40 I1& &93N>N0C*+,/&<O_Yz7�3,( � ,/2-&/3 ),-:/ 3+273+5C--&[sP-7&)6'&)-z3@&9,)(+*+&�-70 ,<79-;&93+ONs¢(+3+&)*3H/b3�)4&<A 243 3�&9,/&<3,3,79*H/9Y�350'3EIE/bG;783,3.78I+--&�-70 ,<79-;&93+ONs¢(+3+&)*j79(5) & &93*)+2-,d7F)42-063 243(3�&9,/&<3H3.79*M/CYWAx(+-7)+24--&26'&)-0s).*H(+3@)PB�0C*�) & / 3�&G)PB0C*HD 2-3+5O243>3�&9,/&<3,3,79*H/D&)6'&/3�20>o--08,d79- 0CG1&<*,7I)4270'3D243x3+2-3K5C--&?--&)66&<-{¥79-7) & 0C(+5 & ,<*M/NGbs)4095C*.79G & 2-,�)4&/, & 3�2:\b(5&<3�,<763�I1&g(+3@&<OB)+0 &/3+3,(+*@& ) & 7I)�2:>�DI&)/b3�79*@&gO�2:3@),*+24IK(5)4&)O�76,/,90C*HO�2-3K5 )4070���$*+&)\E(�24*@&<A(&93*).3)Y 3�0k79OK66&<*H3+& 5 0rBo3�,<763�78*+243@&r�[Y�7I3+O ) & &�).*H(+3@)+&<O�G+7I) & 763+Oh--08,d78-T3H/b3@)+&<A 2-3*)+&<5C*@27)P/AU(+3�)uI.&�3�063�,90CAcG+*@0CA 2:3+2:I+--&8Q

q&<*�)�76273 09>M) & &jO�2:A &/3+3+270'3+3�09>u3H(+*H682:6879I524--2C)P/"79*+&jA(0C*+& ,)*+2C)42-,<79- ) & 763H06) & &<*H3<Q ¡ 0C*�&[1K79A?GK--&9Y3H/b3�)4&<A 273 )+&<5C*@27)P/B243�5'&/3�&<*,79-4-0/ G;79*,79A(0C(�3*)dQ�]¢>F3M/b3@)4&)A 2-3*)4&)5C*+2C)P/D,d7I3 I1&a3,(+IV6'&)*@)+&<O_Y ) & &93�27)�2:3(+3H(;79-4-0/J&d793M/�)+0�3H(+IV6'&<*�)L,90'3 �;O�&93*)+2=79-727)P/CY�7r68762:-=79I524--2C)P/CYS763+O *+&<-72=79I524--2C)P/ 783?B�&<-4-�Q � 3 ) & & 0I) & &)*& 763KO_Y O�&9352=79-:3 09>S3+&)*H682-,/&�,d763O09> )+&93�*+&)3,(+-C)c{@B & &G) & &)*<2-3*)4&/3 )+2-0'3+79-4-0/kG1&<*HG.&G).*,7I)4&)O 09*J76,9,/24O�&/3*)�79-:-:/).*@245C56&<*+&)O��WB;27) & 0C(5) �;*H3@)�3,(+IV66&<*@)+2-3+5e3H/b3@)+&<A 2-3*)4&)5C*+2C)P/CQ %'& (K3<Y�2C) 24379OK682:3.79I+-7&�)40K,90'3+3@24O�&)*�&<76, &O�2:A &/3+3+270'3 2-3L27),3 0rB;3K)+&<*,Ac3 )40lO�&G)4&<*HA 273�& ) & & &[18)4&93*)�09>�) & &<2-3*)+&<*,O5&<G1&93+O�&/3�,927&<3)Q

£f/k-=7d/'&)*+273+5 ) & &�A &/, & 763�2:3,Ac3z>N0C*FGK*+06)+&9,/)+2-0'3�Y¤>¥79(+-C) )+0C--&)*.763�,/&9Y 7I3+O 06) & &<*J793HG.&/,/),3�09>S3,(+*M6 206Vs79I�2:--2C)P/CYE763+O 2-3V6'09D8273+5<) & &M3�06)+2-0'3(09> 5'&/3�&<*,79--2 � &)O?O�&)G.&/3+O�&/3�,9&8YKB&zA 2:5 & ) & 0CG1&M) & 7I)L7�3H(��(,92-&/3*).-:/3,(K*H682:6879I+-7&n3H/b3�)4&<A ,/0C(+-:O &)6'&/3*).(;79-:-:/~I1&�7I)@)�76273�&<O_Q ��0rB�&)66&<*<Y7I,9,9&)3,3 )40�3@&93+3@27)4206'&%0���$ O;7I).7

w �

Page 147: Practical Architectures for Survivable Systems and Networks (Phase

3 & 0C(+-4O 3�06)zI.&�G1&<*,A(27)@)4&)O�B & &/3�&)66&<* ) & &�&/3+ONs¢(+3+&)*F79(5) & &93*)+2-,d7F)42-063 ,<763�3�06)zI1&x5C(;78*.763*)4&/&<O {@B;27) &*+&<793+063;79I+-7&(,/&<*�)�76273 )P/K�[Y$763KO�79-:3+0aB & &935&)6'&)*�) & &?-70 ,<79- &/3+ONsP(K3+&<* 0CG1&<*,7I)4273+5a3H/b3@)+&<A ,d763"I.& ,/0CAlsG+*@0CA 2:3+&)O_Q $ ).*+27,/)XO�&<G1&93KO�&93�,/&L0'3 --&)3,3 ).*,(K3@)PB�0C*@) & / 0�� ]*+&<3@0C(+*@,9&<3�3 & 0C(+-:O�I1&j7d6'0'2:O�&<OB2-3 7I3E/&)66&93*)dQ

w �

Page 148: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

��� � ��! � ! ������� � � � � � ����� ��� ����� � �'� � � �"� �`���� ����� � �

��� � ��� � � �� � � � � ��� � � � ����������� � � � ��� � , �'� � ���� 3�0I) & &)*u*@&<A(2-3+O5&<* 09>�) & &<0C-:Oa3.7d/82-3+5+YK3@)42:-4-�6978--24O

%'& &l79*@, & 27)+&9,G).(+*,79-$3�).*,(5,/).(K*+&<3�763+79-:/ � &)O 2-3hq & 78G5)4&)*�� ,d763�I1&�&)i.&9,G)4206'&<-0/ 2:A?G+-7&<A(&93*)4&)O_Y_7I3+O3,(K*H682:6879I+-7&x3M/N3�)4&)A?3<,d7I3�I.&�&2i &/,/)+2:6'&)-:/ ,90'3 �;5C(+*@&<O�(+3+273+5j3+09A &�,90CAcA &)*+,/2=79-:-:/a7d687624-479I+-7& ,/0CAcG.08s3�&/3 ),3'G+-4(K3) & &F79O+O�2C)42-063;79-;3,(KI+3H/b3@)+&<Ac3;, & 79*.7I,/)4&)*+2 � &<OL273jq & 79G )4&<*��<)40��;-:-1) & &F5V78G+3 24O5&93*)42�� &<O 273q & 79G )4&<* � Q � & &<*@&d793 ) & &FG+*@0�66&<*HI�2=79-¤3+2:-4DlG+(+*H3+&<243�,<--&<79*,-0/c(�3;7I)@)�76273;79I+-7&u>@*@0CA�) & &J3+0rB ��3 &d79*J{¥O�&[s3,G527)4&�7U>N&)B 3H/b3@)+&<A G+(+*M6'&2/'0C*H3zB & 0cB0C(K-4O & 7d6'&/'0C(kI.&)--27&)6'&<06) & &<*MB;243@&r�2Y 2C)oAU(+3�)zI1&*+&/,90C5'352 � &)O>@*+09A ) & &�09(5).3@&/)>) & 7I)X3,(+IK3@)�7I3 )+2:66&j*+243HDE3XB;24-:-�*+&)Ag76273 350nAg7F)+)4&)*�B & 7I)xB�&vO�0+Y�I.&/,d79(K3+&gB�&j79*@&--20682-3+5(2-3 ) & &U*@&d79-`B09*,-4Oe*.7I) & &<* ) & 763n3@0CA(&>24O5&d79-72 � &)Ok>¥763*).793H/�B09*,-4O�Q %'& &�, & 78-4--&/3+5'&�243�)+0vA(2-3Ns24A(2 � & ) & 0C3@&�*+243HDE3JIE/e*+&)-:/82-3+5 063�763�79*+, & 27)4&/,/),(+*+&�) & 7I)�2:3F3@),*,(�,G).(+*,79-4-0/e3@0C(�3+O_Y 2:A?GK--&<A(&93*).7I)4270'3+3) & 7I)o79*@&W*+09I+(+3@)LB & &<*@& ) & &2/�3�&/&<O )40UI1&F*@0CI+(+3�)dY�0CG1&<*,7I)4270'3;79-�G+*,76,/)+2-,/& ) & 7F)�O�08&<3 3�0I)�(�3+O5&<*,A(2-35&) & &�5'2:66&93�*+&)\E(�24*@&<A(&93*).3)Y�7I3+O�*+&<79-0s )424A(&X763;79-0/N3@243 )+0 09-43�) & 7I)�,<763�*.78G�24O+-0/ 2:O�&93*)+2:>�/K&d79*H-:/K) & *@&d7I),3)40l3H(+*H682:6879I524--2C)P/v7I3+Ok*@&<3HG.0'3KOe76,/,90C*HO�2-3K5C-:/9Q

���� ������� ��� � ��!#" � �#$ � � � � � � � �&% �(' � � �

¡ 273;79-4-0/CYoI;793@&<O�0'3 ) & &�>N0C*+&)5'0'273+5�O�243@,<(+3H3+270'3_YWB�&�78*+&�*+&<79OK/ )+0 G+( )K) & &�G�2-&/,9&)3L)+0C5'&G) & &)*<Q �3+09A &2B & 7I)u3+2:A?G+-7243�)42-,u3,(KA?A?79*H/ 09>�) & &O�&)3+24*@&<OkG+*+08,9&)3,3;243o793'>N0C-:--0rBo3<��CQ %'& &UA 2:3,3@2-0'3k*+&<\E(�2:*+&)A &/3 ),3JAU(+3�) �;*H3@)JI1&�,909A?G+*@& & &/3+3+206'&)-:/�7I3+O ,d78*+&)>@(K-4-:/�O�& � 3�&)O_Y 24O�&<79-4-0/783o7c*@& � 3�&)A &/3*)W7I3+O &[18)4&93K3+2-063 09>$763K&<3�)�79I+-7243 & &<O�3+&G)�08>$O�&G)�762:--&)Oj5'&93�&)*+27,�*@&<\E(�2:*+&<A(&93*),3<Q

�NQ %'& &F3,G1&9,/2�� ,FA(243H3+270'3?*@&<\E(�2:*+&<A(&93*),3'AU(+3@)LI.& &)6879-4(+7I)4&)Og>N0C* ,90CAcG+--&G)4&/3�&<3H3<Y+3@&<-:>=s ,90'3K3+243�)4&/3�,)/9Y7I3+Oh76,9,)(+*.76,2/CY^763+Oh3+09A &�*@243,De763;79-0/b3+&<3O�063�&�)40L&93K3,(+*@&() & 7I)�) & 0C3+&lA(243,3@2-0'3e*+&<\E(�2:*+&)A &/3 ),378*+&�2-3KO�&9&)Oe79GKG+*+0CGK*+2=7F)4&9Q

�KQ � 2:66&93 ) & &�3,G1&9,/2�� ,�*+&)\E(�24*@&<A(&93*).3)YF7 G+*@&<--2:A 273;79*M/�3,D6&G)4, & 09>�) & &�O�&)3+24*@&<O 79*@, & 27)+&9,/),(+*+& 09*78-7)4&)*+3;7F)42:66&J79*@, & 27)+&9,/),(+*+&)3z3 & 0C(+-:OaI.&<,d78*,*+27&<OL0C(5)<Q

)�*,+

Page 149: Practical Architectures for Survivable Systems and Networks (Phase

� Q %'& &k3@&<--&/,/)+&<O O5&/)�7I24--&)O 78*+, & 2C)4&9,G).(+*@&k3 & 0C(+-:OH) & &93 I.&"5 &)3 & &)O 0C(5)?763+O�O�08,<(+A(&93*)+&<O 3H(���s,/2-&/3 ),-:/ )40 &/3;79I+-7&j7 )40CGbsP--&26'&)-&21K79A(2-3+7I)4270'3D09>oB & &G) & &)*�) & &v>@(�35,/)4270'3;79-L763+O�G1&<*M>N0C*,A?763�,/&*@&<\E(�2:*+&<A(&93*),3z78*+&�7I)+).762-3+79I+--&8Q

�NQ � 3,3H(+A 273+5 ) & 7I)?7�*@&)682-&2B 09>;) & &aG+*+&26 270C(+3 27)+&<Ac3�243l7I,9,9&)G5)�78I+--&8YL7�O�&G)�762:--&<O�G+-4763 >N0C*�3M/N3Zs)+&<A &26'0C-:(5)4270'3�3 & 0C(+-:O�I1&?A?79O�&8YT763+O ) & &?O�&/).7624-7&<Oh3H/b3@)+&<A O�&<3@245'3�3 & 0C(K-4O�I1&(,d79*H*+2-&)OB0C( )7I,9,909*,O�273+5�)40�) & 7F)oG+-=763�Q

�KQ � O5&/)�7I24--&)O 24AcG+--&)A &/3*)�7I)+2-0'3�7I3+O )4&<3�)�G+-=763�3 & 0C(+-:O & 7r66&?I1&9&/3"O5&)6'&)--0CG1&<O 2-3�G;78*.79-:--&<-`B;27) &) & &W3M/b3@)4&)A O�&)3+2:5'3_Q %'& &F3M/b3@)4&)A AU(K3@) 3�0rB I1& 24AcG+-7&<A(&93*)4&)Ov763+O )4&<3�)4&)Ok7I,9,909*,O�273+5�)+0>) & 7F)GK-=763_Q %'& & 24AcG+--&)A &/3 ).7I)4270'3nG+-4763�3 & 0C(+-4O"79O+OK*+&<3H3A 0bO+(+-7&�,90CAcG.093.79I�2:--2C)P/jB;27) & *+&)3,G1&9,G) )+0273*)4&<59*.7I)+2-0'3_Y8)4&)3@)4273+5+Y;7I3+O ,/0'3��;59(+*.7I)+2-0'3jA?763;785'&<A(&93*)dY+763+O�3H/b3@)+&<A &)660C-4( )42-063_Q

�NQ�q063+3+2:O�&<*,79I+--& ,<79*+&�AU(+3�)cI.&aO�&26'06)+&<O )+0 09G.&)*.7I)+2-0'3;78- ,90'3K3+24O5&<*.7F)42-063+3<Q %'& &�I.&)3@)c3H/b3�)4&<Ac3273 ) & &gB�0C*,-:O�A?7r/hI1&v(+3@&<--&)3,3U(53+--&)3,3>) & &92:*>0CG1&<*,7I)4270'3B2:3XA?763;7956&d79I+-7&9Q � 3HG.&/,/).3�08>;0CG.&)*.7ws)+2-0'3+79-LG+*,76,/)+2-,/&�Ax(+3@)?I.&a*@&<G+*@&<3+&/3*)4&<O 2-3J) & &L&d78*,--27&<*�3�)�795'&)3<YfG;79*@)+2-,)(+-=79*H-:/ 2-3J&<3�)�79IK--243 & 2-3K5*@&<\E(�2:*+&<A(&93*),3L763KO 273 ,<79*,*M/ 273+5 0C(5)S3H/b3@)+&<A O�&)3+24563v763+O(24AcG+-7&<A(&93*)�7I)+2-0'3�Q � 080NO 0CG1&<*,7I)4270'3;79-GK*.76,G)42-,/&zAx(+3@) ) & &/3vI1&�&/3K>N0C*+,/&<OvOK(+*+273+5X(K3+&9YK763+OcB & 7I)4&26'&)* & &<-:G ,<763gI1&W5V7I2-3�&)O?O+(K*+2-3K5�) & &O5&)6'&)--0CGKA &/3 )M,2/ ,)--&JB;24-:-�I1&J6'&<*M/j6879-4(;78I+--&8Q

��� � � ' $ � ' � " %�� ��$ � �#$ � � � � � � � � $ �� � ' � '��#$ � �

� 3H(���.79I+-�W79* � & �������,(+* F>��C*f3,(+*M6��:6879I+-�����PB��C*HDb3��9>`3H(+*H6��06978I+-�F3M/b3���)A?3'A��45 & ���P/bG����<79-4-0/?I������� & 7���������CA?G+793,3�<3�� & �C3 �9>�� & o>��C-4-�rB����+5JO�)3 �:O�<*,7���7O��)A!)Og3H(���.79I+-�'>��C*"� & z5#�:6���v79GKG+-���d7�� ��������$� & %�d793�&�9>'O�)O����<7���)O�3H/b3�� <Ac3<Y"�C*'� & ?>@(+-4-�*.7��+5�%�8>�21NG����� <O�79G+G+-���<7�������+3(���$� & !�d793�&�9>3H/b3)��<Ac3�� & 7��u78* A!�9* J5����<*,79-0s¢G+(+*,G��C3�9Q* � 3,3H(+A!n7#�+�CG���Ns¢3H/b3�� <A 79G+G+*��V7#� & � & 7��&�:3%�<79G;79I+-,�9>J7#�����CA?A��bO;7�����+5$���CAcG��#����-�.3!�9>Ax(+-� �4G+-�6���KO��C*,3)Y+O��0i.)* ��-�����CAcG��#����-�.3S>@* �CA 7#�V/cG;79*)����<(+-479*�6���KO��C*,3)Y+O��0i.)* ��-� & 79*,ONB�79*�GK-=7��H>��C*,Ac3<YbAU(+-/���4GK-�FG+*��#�������9-43<YK7#�+O�O��:i�<*���-�uO;7��.7�>��9*,A?7��.3)Q

* �FI+3�<*M6�o793H3 �4OK(��C(+3H-:/(� & LG+* ������:G+-�)30�C(1�.-����<O2���43����� ����� �NQ:��7#�+O5� & �* )3��"�8>�� & L3.795��79OK6�������aq & 79G1��<*��bYNB & )* )6#<*uG��93,3 �:I+-�8Q63 & �9*��Hs¢3 �:5 & ��<O72i.�9*��.38�P/bG���d79-:-:/lO��:3 �<79*,O7� & <3 JGK* �������4GK-�<3783�� �1�4[1KG���K3 �:6#U7#�KO9� �1�:���:A![s;�����+3,(KA!��+5+Q�� ��B�)6#<*)Y�>¥79*ZsP3��45 & ��)OaO�)6#<-��9G�)*,3W(��+O�<*H3��.7#�+O� & (�4AcG��9*���7�������8>0� & <3�XG+*��������4G+-<3)Y�§H(+O������C(+3,-0/j79GKG+-��<O_Q

* ¡ 7#���4-���7<��=)6#�C-4(1�����#�;79*H/aA��bO����>�<7�������+3��9> & 78*,OKBL79* 8Y?�CG�<*,7�����+5g3M/N3)��)A?3)Y 79G+G+-���<7�������a3 �9>@�MsBL79*�9YV79OKO��� �����2�9>>��2B GK* �#� �1���C-43$7#�+OA��2BB�4AcG+-�)A!��C�.7�������+3)Y87��+O:���+O��<O2���#�.79-N*�<G+-47#��)A!��-��8>D��C� �4*�J3,(+I+3M/b3���)A?3uB & <*�)6#<*WO�<3 �:*.79IK-�9Q

* 09�����:A!� � D� & �3 ���9G���9>��,*,(+3)�PB��9*�� & ����)3,3<Y8B��� & 7'A!�¦1��.(+*���8> & �:5 & s;��-��<59* ��P/E���9A?G�������C�,3`3,(�� &7830���:5 & �.-0/79O+A������:3�� <* )O2�,*,(+3)�PB��C*)� & /��+* )BL79-:-43�7#�+OU3�<*H6#<*H3��#�5���� & 7#�+O�YV7#�+OA�#�+-:/�G;79*)���479-4-0/�,*,(+3)��)O$�9*����CAcG+-���)-:/k(��-�.*H(+3�� <O$��-���/����)3=���F� & :�#� & )* & 7#�+O�Y_B��� & 6879*����C(K3����-��)*,A�<O��47���O�<5C*��<3 �9>G�.*H(+3��PB��C*�� & ����<3,3z793o* )\E(��4*�<O_Q

* ��*���6��:O��* �CIK(+3��H����<*M/NG1�����#�>��9*?���-��)5C* �/�P/CYw79(�� & ��-� ���d7<�����#�_YI����� �;O���-� �=79-��P/ � & *��C(+5 & �9(��dYdB & )*Ms26�)*"78G+G+* �9G+* �47���8YU7d6����:O����K5~D#)/Vs¢* ����r6�<*M/�7��+O�D#)/VsJ<3 �)* �rB 3 � & <A�<3�B & <*�)6�)*�G��C3,3��4I+-9Q

)�* )

Page 150: Practical Architectures for Survivable Systems and Networks (Phase

� & <* 26�)*�B��4* )-�)3,3����CAcAU(�����d7�� �����+3S79*�W(+3�<O_Y1� & 2/gAU(K3��'I� & �:5 & -0/l* <-�=79IK-�u7#�+Ov3�<*����C(+3H-:/GK* �#� ���� <Oa>��C* ���#���;O���C� �=79-��P/v7#�+O9���-��)5C* �/�P/CQ

* ];���<-4(KO� 21�����+3 �06��A!�� & 7#���:3,Ac3F��� & ���KO�<*�O�����=79-¦s;�9>=s¢3 )*H6����� 7�����7#��DE3$��� & �C3��,3<Yl3 )*H6#<*,3)Y*��C(�� <*,3)YS7#�+O �#� & <*U3M/N3)��)A?3)Q � & <*�)6#<*lB��4* )-�)3,3:���9A?AU(������<7�������+3X79* j(+3�<O_Yf79-/��<*��;7�� �:6�G+7�� & 3oAU(K3���211�:3������ & ��+O�<*oO�����=78-0s;�8>=sP3 )*H6�����J7�����7#��DE3<Q

* ��*���6��:O�J3H/b3�� <A�����79(�� & ��-� ���d7<�����#�aB & <* 26�)*E�����)3,3.78*H/CY¤7d6����:O����K5c*�<(+3,79I+- �K11<OeG+793,3MB��C*HO+37��+Oa79-43���7d6����:O����K5�3 ���K5C-�[sP3 �:5��NsJ���+3�211��)G��oB��� & ���v3H(���������-�.-:/!�.*H(+3��PB��C*�� & /7����)-=7d6�)3X{ �:>^7��E/3H(�� & ����<-47d6�<3 �d7��e7#� �.(;78-4-:/!211�:3��dY+B & ��� & 3 �)A?3'6#<*H/aO��C(+I��H>@(+- � �2Q

* ];���<-4(KO� �,*,(+3)��<O~G+7�� & 3?B & <*�)6�)*7�����<3H3.79*M/CYWG+79*�� ���<(K-=79*H-:/ B & ���)6#<*a7�-�1�<79-'B��9*,DE3��.7�������Ax(+3��gI�9�.*,(K3���)O_YoB & ��~3�<*H6#<*H3�Ax(+3��gI�kAg7#��-��7#���<O_Y�7#�+O 5����<*,79-4-0/�B & ���26�)*7�<* �/����d79-3��9>@�PBL79* AU(+3)�uI�(+G+59*.79O�)O_Q

* ¡ 7#���4-���7<��:� & j(K3 7�9>uO�)A!���K3��.*,79I+-0/ �,*,(+3)�PB��C*)� & /�A��CI��:-�����bO�a793�79GKG+* �CGK* �=7<��9Y�7��+O �#� & s)*HB��:3 �����K3��.*,7#��� � & "G+*�<3������ �9>x(��-�.*,(K3��PB��C*�� & / A��CI��4-F���bO� {¥G�<* & 79G+39��� 7�G+* �CG�<*H-:/����d78G+3,(+-47���)O�3.7#�+OKI��d1$�C*���� & )*HB��43�4����������<O$��V6��4*����+A���-�=� & 7<�(�d7#�����#�'�����-��78A!��;7���2��,3G��)*,3��C* & �<*,79* � & ��d79-�O�<G���+O���-�.3.�2Q

* � �����CA?A��bO;7���S5����<*,79-�� � <OXO�<G���KO������'B & ���26�)*�7W3��,* ��� �TO�)G���+O��������d7������#�$I����+3H(+* )O_Q* � �����CA?A��bO;7���!� & 70��G3�7��+O 0 �`]x* <\E(��:* )A!��C�,3�B & ���26�)*&<3H3 ��-� �=79-�YfG+*�)>�)*.79I+-0/�IV/�* [s3��C*�� ���+5:� �g7c3 <-�� ���:6#2s �.*,(K3��PB��C*�� & ����)3,3X0F3 �^�40��G3e79GKG+* �V7�� & 3,(�� & 793 � & 7<� �9>T��* �������9*z7��+Om <(+A?7#���"}��K�r�8��{¥3 �A3����� ����� �NQ �C�[Q

* � �����CA?A��bO;7���8� & o3,G��:* �/�6�9>�Ax(+-� �4-�26�)-+3,(+*M6��:6879I��:-���P/X-����d78-4-:/�B & )* ��6�43S79GKG+* �CGK* �=7<��9YCB��/� & s�9(���7�����)A?G�� ���+5 ���=��K>��C* ���5C-�CI;79-&0����~G+*��CG�<*�� ��)3o{@B & �:-����79DC���K5J79OK687#�-��785���9>�5����<*,79-�� � )OO�<G���+O������d�2Q

* ��*���6��:O�721�����+3 �06� ���r6#<*.785� �9>o6N(K-���)*.79I��:-��/����)3x7��+O � & *�d7��,3A� & 7��4�<7#��I�jG+* 26���-� <O_Y'7��+O>@(K*�� & <* ����6#<*,795���9> � & *�d7��,3 � & 7<��B & ��421NG+-���� <O:�<7#�l3����:-4-bI�8� �C-�)*.7�� <OA� �J3 �CA��* <793 �#�;79I+-[1�����-�<Q

* ];���<-4(KO�:���CAcG+*� & ��+3 �06�l>¥7#���:-��� ��)3u>��C*W* d78-0sJ� �4A�xA������/���C*����+5+Y�* <79-0s ���:A!X7#�;79-0/b3 �43)Y`7#�+O�* <79-0s� �4A�U* )3,G����+3��� & 7��X7#�4O �� � & cAg7#��-����+7#����:�8>�3,(K*H6��:6879I��:-��/�P/n7#�KO �/�.3J3,(KI�����+O�<O�* <\E(��:* [sA���-�,37��F6879* ��C(+3F-47d/�<*H3(�9>f79I+3��,*.7#� ������_Y�>@*��CA & 78*,OKBL79* A� � �CG�)*.7�� ���+5g3H/b3�� <Ac3(� �a3 <*M6�)*,3� ��79G+G+-���d7<�����#�+3D���(��C� �4*� ����PB��C*,D�<O7��-� <*,GK* �43�<3)Q %'& <3�z>¥7#���4-��/���<3$3 & �C(+-:O?I���d79G+79I+-���9>¤O�[s� �� �����K5�-�:6#�� & *�d7��,3"� & 7���>¥7#�:-�)O_Y#� & 7��6���C(K-4O4���#��I�oG+* 26���-� <O_YK7#�+O4� & 7��6���C(+-:OcI� ���C-<*,7���)O7<� � & A��CA!��-�'I+(���� & 7��uA!�:5 & �'* )G+* )3 ��-�E��������<*��+3 ���7� & J>@(��,(+* 8Q

t���.7#�4-<Oe7#�;79-0/N3��43��8>�� & :�d7��+O��4O+7����78* � & �/���� �.(+*�:�43 � & �� ���<O�)O$� � )6879-4(+7���'� & l79GKG+* �CGK* �0s7�� ���)3,34�9>�� & v79* � & �/������.(K* 9YS7#�KO�O����7��4-�)O�7#�;78-:/b3 �:3A�9> � & v>�d793��4I��:-���P/ �8>E�/�.3X3,(�����<3H3H>@(+-��:A?G+-2sA���-��7�� ����� �:3=���)O�<O � �aO��� <*,A�����lB & �� & <*'��(�43FB��C*)� & GK(+*,3H(����+5 � & cG+79*�� ���<(K-=79*J78* � & �/���� �.(+*�>@(+*)� & )*<Q %'& �:3"�43"�)-�d78*,-:/x7#�4�� <*,7����06��G+*��1��<3H3�B & ���26�<*�� & o7��;79-:/b3��43TO� ��)*,A�����)3"���;79O�<\E(;7#����<36��� & '�<7#�+O��:O;7�� X78* � & �/���� �.(+*�9QS];�k3��CA�'�<793 )3<Y ��oA?7d/jI�X78G+G+* �9G+* �47����� �cGK(+*,3H(�x78-��)* �;7<���:6#=�d7#�bsO��:O;7���u79*�� & �� �� �.(+*�<3��C*�6978* �=7��C�,3"� & )* ��8> ���lG;79*,79-4-<-bp 7��S-d793)�f(��C� �4-;A��C3��6�8>.� & �C3 z79-� <*��;7����06�)3�d7��kI�O��43��d79*HO�<O9���j>¥7d6��C* �8>D�)-�d78*oB������)*,3<Q

)�*

Page 151: Practical Architectures for Survivable Systems and Networks (Phase

��

� � � � � ��� ! � � �#$ � � � � � � � � $ �� � ' � '��#$ � �� 3H(���.79I+-�gI;793 )-����g>¥79A��4-0/ �9>z79* � & �������,(+* )3��:3A���rB )6��4O���-��>@* �CA � & jGK* ���<O���+5F��[1��4�9>�� & �:3* )G��9*��dQ* % �bO;7d/CY -����d78-D��KONsP(+3�<*�3H/b3�� <Ac3�79* A�P/bG���d79-:-:/ ���#�=�.*H(+3��PB��C*)� & /CY^B��� & *�<3HG�����'��� ���-��)5C* �/�P/CY7d687#�:-=79I��:-��/�P/CY ����� �;O���-� �=79-��P/CY *�<-�=79I��:-��/�P/CY¤7#�+O �#� & <*�7�� �,* �:I+(���)3=�9>f3,(+*M61�06879I��4-��P/9Q %'& (+3)Y0� & O�<3 �:* )O?I;783 <-����u79*�� & �� �� �.(+*�<3SAU(+3������#������C�,*.7�� �,*,(+3)�PB��9*�� & ����)3,3fB & <* E��6�:3SA��C3)�6���)O�<O7��+OjB & <*�2�/���d7#�aI��A��C3)��)i����� �:6#9Q

* %'& LO�26�<-�CG+A���-�dY������ �;5C(+*,7�������_Y87#�+Ox(K3 ��8>�� & ��Ns;�)-����-�H��+ObsP(+3�<*$GK-=7��H>��C*,Ac3H�43`3��,* ���+59-:/(��bs���C(+*,795�<O�Q�3���79*HDv3,(KI+3 � ����+5��9>G211�43)�����K5c3M/b3���)A?3 ���9(+-4Oj*�<3,(K-� ���jAU(�� & 5C*�d7�� <*'*��CI+(+3)����)3,3B��/� & *�<\E(��:3 �� �.*H(+3��PB��C*)� & ���<3H3 ���%� & F3 & �C*��8� <*HAkQ � ��B�)6#<*)Y>���%� & J-����K52��)*,A�Y1� & ���NsJ�<-����-�3M/b3���)A?3a3 & �C(+-:O~I��O�26�)-��CG�<O B��� & §H(+3��7� & �A!����4A?79-'>@(���� ������;79-��P/�* )\b(��4* )O_Q { % *,7#�+3ZsA���.7 ��3L-��rB�s¢G��rB�<*8���21NG���+3��:6�=� & �4GjA?7r/?I�J7U3�� <G ���%� & 7��LO��4*����� ������Y+79-/� & �C(K5 & � & =�����/���479-�8i.)* ���K5�79G+G;78* ��-�,-:/+����<-:(+O�)3j7�>@(+-4-¦sPI+-�rB�� � ���E(N1+�CG�)*.7�� ���+5�3H/b3�� <A�Q�� % �bO;7d/ ��3aI+-��C7���)OA?793H3MsPA?79*HD#��FG�)*,3 �#�;79-0sJ���CAcG+(�� <*��9G�)*.7�� ���+5j3M/N3)��)A?3�7#�+Oh7#�����CAcG;7#�V/����K5�A��4OKO+-�2B�79*��79*��)-�<79*,-0/%��;79G+G+*��CG+*��=7�� WB & ���)6�)* �,*,(+3)�PB��9*�� & ����)3,3 �:38<3H3 ��C� �=79-�Q��E�rB�26�)*<Y��� �:38� & )* )>��9* (<3Zs3���-���479-D� & 7��79*�� & �� �� �.(+*�<3'���CAcG���+3.7<��U>��C*FO� �>������-�'��KONsP(+3�<*(���9A?G�������C�,3?{@>��C*�[1K79A?GK-�9YIV/j5#���)*.79-� � )ONsPO�<G���+O�������A��� & 7#���43,Ac3��[Q

* qL*��� ���d78-8>@(���� ������;79-��P/uAU(+3)��I��A��4-��/��7#�-�,-:/��43��C-=7<��<Ozp >��9*?21K79AcG+-�8Y�IE/JB�<-:-0s¢Ag7#�+795�<O & �45 & -:/�,*,(+3)�PB��9*�� & / �;*�)BL79-4-:3<Y8��K>��C* ��<O G & /N3����<79-z3�<G;78*.7�� �����_YL7#�+O �d79*�)>@(+-:-:/ A������/���C*�<O�-��95����<79-4-0/-47d/�<*�<O�G+* ������ ������_Y+3H(+Ib§��� �E� �?3���+3��4I+-7#�+O ���:5 & �.-:/!��N>��C* ��d79I+-G��C-������<3)Q

* 3�<*H6#<*H3<YW*��C(�� <*,3)YF7#�KO �#� & )*7�<*������d79- ���N>@*.793)�.*,(����.(K*.79-E���CAcG��#����-�.3jAx(+3��jI��3 �:5������>�d7#�-�,-:/A��C*��3H(+*H6��06978I+-�k7#�+OB�.*,(K3��PB��C*�� & /9Yu7#�+O+�� G;78*�����<(+-479*�* )3 �:-�����-�g785V7#���K3��?O�����479-0sJ�9>=sP3�<*M61���7<� ��7���Db3)Q �E�rB�)6�)*<Y�� & )* �436����* d783 ����� & 7��6� & )/ & 7d6# � �XI�zIK(��4-/�"���l>@(+-4-0/U5����<*,79-0s¢G+(+*,G��C3��9G�)*.7�� ���+5U3M/b3���)A?3)Y;B��� & 78-4-�� & F6b(+-���<*.78I��4-����<36� & 7<����-��7#�:-43)Q %'& (+3<Y>� & <3 (�)* �� ���<79-����CAcG��8s����-�.3����<O7��� & 7d6�3HG�����=78-0sPGK(+*,G��C3 �CG�)*.7�� ���+5x3H/b3�� <Ac3<Y �����/���479-4-0/U3��.79*,D?3,(+IK3 ��,3E�8>G� �NO+7r/ ��33M/b3���)A?3)Y$7��+O 26���C�,(;79-:-:/�3H/b3)��<Ac3(� & 7��X79*�l5����)*.7�� <O�7#�+O$�������+5C(+* )O�3HG�����=78-4-:/�>��C*�� & ��:*��-����KO�<Ok79G+G+-���<7�������+3<Q

* %'& �O�����479-0sJ�9>=sP3�<*H6����WGK* �CI+-<A�AU(+3��uI�79O+O+*�<3H3 <Oe793u7#� ���-��)5C*.78-�G;79*)���9>G� & 3H/b3)��<A 7��+O����PB��C*,D�79*�� & �� ����,(+* )3<Q � ���CAxI����;7<�����#� �9>J79(1� & ��C� ���<7������� 7��+O *��CI+(+3)� & 7��+O+3 & 79DC���+5 ����+* )BL79-:-43^7#�+OX* �C(�� <*H3<Y �+-��)* ��+5E�8>��CIV6����C(K3,-:/(���������9A?G+-�=7#�-� �,*.7 ���9Y97#�+O�(+3 ��9>>�)*H/bG����95C*.79G & /A��45 & � & )-4G,� �v3��.7d6�A�9i ��)*��.7#���9�P/NG�<3=�8>�7�� �.7#��DE3<Q % �v3��CA!XO�<59* �8Y 7cB��:-4-���+5���<3,3�������79D�7cG�)*H>��C*HAg7����� & �� �43 �����<3,3,79*H/eB & �� �)* �� ���<79-`* <\E(��:* )A!��C�,3FAU(+3)�JI�xA���dQ � -/� & �C(K5 & � & A?7#��NsP-����4���9A?A�<*����=78-fG+*��NOK(����,3�5����)*.79-:-:/�79* j(��EB��:-4-���+59����79-:-��rB � & 7<�:��� & 79GKG���_Y��/�A�:3�����)3,3,79*H/j>��C*�����<*�d793�<O�* �CI+(K3�����<3,3)Q

* %'& k78* � & �/���� �.(+*�aAU(+3��4������9A?G;783,3:� & ���<O+3��9>zOK/��;79A����<79-4-0/ �������;59(+*.79IK-�a7#�+O�*,79G��4OK-:/*���������;5C(K*.79I+-xB�<-4-¦sPG+*��#������ <O�B��4*�<-�)3,3=���CA?Ax(������<7�������+3z7#�+O�G��C*��.79I+-�XG+-=7<�,>��C*HA?3)Y¤6��4*)�.(;79-GK* �:687�� A�� �PB��C*HDE3<Y ��+ONsJ� �8s;��+O ����)*H/bG�� �����_Y^-���+D9����)*H/bG��������B & <*�g79GKG+* �CGK* �=7<��9Y �+* )BL79-:-43<Y7��+O:�43��C-=7�� <OA��-�.*.7�����,3TB��� & �<79* 2>@(+-4-0/'�����-�.*��C-4-<O�7�����)3,3"���A��C* f5C-��9I;79-�����PB��C*,DC��+5(�����)-4(+ONs��+5A� & �];�-� <* ����dQ

)�*,*

Page 152: Practical Architectures for Survivable Systems and Networks (Phase

* %'& U79*�� & �� ����,(+* XAU(+3)�J79O+OK* <3H3F7cA!�CI��4-�[s;���NO�G;78*.79O��:5CA � & 7��E�43u3,(��/��79I+-0/ �����K3��.*,7#����<O � �GK* )6#��-�z(��+O�)3 �4*,79I+-JI� & 7d61��C*<Qz{ 31�231��������� �NQ � Q��

]PAcG+-�)A!��C� ���+5�3H/b3)��<Ac3�� & 7�������� & �43SD���+O&�9>_I;793 )-����F79*�� & �� �� �.(+*�W* )Ag7����+3f7 & (+5��� & 79-4-��+5�>��C*5� & j>@(��.(K* 9Q £L(��l3,(�� & 7�3��,*.7�� <59/ �43�-�4D#)-:/$����I�&� & ���K-:/"3,(�����<3H3H>@(+-uG;7�� & ���F� & a>@(1�.(+*�B & ���)6#<*U3M/N3)��)A?3B��� & �)* �� ���<79-$3H(+*H6��:6879I��4-��/�P/n*�<\E(��4*�<A���-�.3X79*�����<O�<O_Q %'& ![1K7#���X* �C-A� & 7<��CG���Ns¢I��d1 3 �9>@�PBL79* aA��45 & �xG+-=7d/ *�<A?7#���K35����I�jO��� <*,A�����<O_Y�G;79*)����<(+-479*,-0/ ��� �CI��.7#������+5e*��CI+(+3)����9A?G�������C�,3A� & 7<�:�#� & <*HB��:3 aO�� �����:211�43)�:���bO;7d/CQ"]J�.3�G��#����C� �=79-��43A�����+3��4O�)*.79I+-j7#�+O�AU(K3��lI�21NG+-�C* )O ��aO���.7#�4-�YK3,(KG+G��9*���)OkIV/ �>�+7#�����479- 7#�KO �#� & <* �������-���:6#<3)Q3N(�� & 7X3��.*����+5C-0/cG;79*�� �� ������)O%�� �PB��9*,Dv78* � & �/���� �.(+*�zB��/� & 3)�.* ������43 �9-=7�� �����?7#�+Og6#<*M/&���#�C�,* �C-:-�)O

���N>��C*,A?7������� 5>�rB 7#�)* �C3H3SB�<-:-0s¢O� �>��<Ov7��+OcB�<-:-0sP79O+A������:3���)* )OcI��C(��KO;79* �<36�43S79IK3 �C-:(���)-:/:)3,3 ��-���=78-���7��E/xG+* �0687�������-�.*,7#����,3D� & 7���79*�'(+3 )Ol>��9*TA!�:3,3������NsJ�<*������d79-9G+(+*,G��C3�<3<Q %'& <* �:3 ���#� & ���K5�21��.*,7#�C*ZsO���;79*H/v79I��C(��uA!�:-��/��79*M/4���)O+3W783o>¥78*o793 � & =���� & ���C-�C59/7�:3 ��������<*���<O�Q�t��45#���78-����CAcA!)* ��3 & 79* )3A?7#�V/ �8> � & &���<OK3x>��C*x3H(+*H6��06978I��4-��P/CY�7#�+O�G+79*�� ���<(K-=79*H-:/�*��CI+(+3)����)3,3<Y6��C� <5C*���P/9Y�7#�+O GK* )6#��-�������9>SO�����=79-:3 �9>�3�<*M61���8Q'0e7��E/eI+(+3�����)3,3 )3 & 7d6�l3 �:A!�:-=79*����<O+3)QX];�F� & l79I+3������:�9>�d793M/n3 �9-4(�� �����+3���7� & �C3 4���<O+3)YH)6�)*H/#����%�:3=�CG�<*.7<�����K5a7��J* �:3,D�Q %'& � Q 3¤Q � �r6�)* �+A���-�'���)O+3(���7��79D�c7vAU(�� &3��,* ���K5�<** �9-�:��� �:O���-���0>�/����+5&� & 4�<* �/����d79-�* <\E(��:* )A!��C�,3x7��+O ���+O����K5aBL7d/b3'� � �:A?G+*��r6��G+*��1�)(+* [sA���-�X7#�+O$��������-���06�<3'��� ��K3,(+*�!� & 7��(� & �C3�?*�<\E(��:* <A���-�,3XI��>@(+-��;-:-�)O_Q %'& �;*,3)�x3)��<G ���V6��9-:6�)3�<-d79*'*�����C5����/�����#�7�9>0� & (�<*������d79-¤* )\b(��4* )A!��-�.3z7#�+OaO+*.78Ag7�� �����:A?GK* �r6�)A!��C�,3���� <O+(��d7�� �����_Q

%'& &)A!)*,5���+5 % 7#� �����<79-S];�C� <*�����:�:3U7#� �4O�<79-���V61�:* ���KA!��C�A���"B & ��� & ���,21NG+-��9* !� & vA�<*���.3�9>E� & & �45 & -:/�GK* �������4GK-�<O�79*�� & �� �� �.(+*,79-u7#�+OB�CG�)*.7�� �����+79-o79G+G+*��V7#� & )3%�C(1�.-����<O ��B� & �43l* )G��9*��dQ%'& % 7#� �����<79-�];�C� <*�����'*�<G+*�<3���-�.3o75���CAUI���;7�� �������9>H21��,* <A�<-0/��<* �/����d79-;*�<\E(��4*�<A���-�.3)Y������<-4(KO����+5* <79-0s ���:A!UG�<*M>��C*,A?7#����g7��+O [11�,*.7#�9*,O���;79* �:-:/15>211�4IK-�l*.79G��4O�*���������;5C(K*.7�� �����_YG���"79O+O�������� ���9��,33��,* ��+5���-�u* )\E(��4*�<A���-�.3'>��C*'3���<(K* ��P/�7��+Oa* <-�=79I��4-��/�P/CQ

)�* �

Page 153: Practical Architectures for Survivable Systems and Networks (Phase

� ��������� �

� ��� � ��� �"��� � �

� � � � � � ��� � � � � � ��� �� � � ���$��� �� ��� ������� � ��� �&�� �� � � ���Q+R�ONB�79*HO+3Ft�)A!��+5

%'& A�)(+*,*���-�.-0/,[11�43�� ���+5gG��CGK(+-=79* ���9A?A�<*����=78-4-:/j7r687#�:-=79IK-�(���CAcG+(�� <*Zs;���9A?AU(������<7�������a3,(+I+3M/b3Ms��)A?3o78* F>@(��+O+79A!��-��79-:-:/����;78O�<\E(;7�� J>��C*�� & �O�)6�)-��CGKA!��C�u7��+Oa* d78OK/7���#���;5C(+*,7�������7�9>^3H/b3)��<Ac37#�+O ����PB��C*HDb3zB��� & �<*������d79-�* <\E(��:* )A!��C�,3z>��C*u5����<*,79-�� � <O�3,(K*H6��:6879I��:-��/�P/CQ�mu(+A�<* �9(+3z5#�1�bO �:O�d783211�:3��'���F� & l* <3�d79*�� & ���CA?Ax(�����P/9Y_I+(��X79*�UB��4O�)-:/,�45����9* <O �� ���CAcA!)* ���=79-�G+*.7#� �����9Q � �rB�26�<*)Y79-/� & �C(K5 & �/�!�:3!� & ��C*��� ���d78-4-:/ G��C3H3 �:I+-� ���"O�<3��45�� O�<G���+O;78I+-�k3H/b3�� <Ac37�C(��!�9>J-�)3,3ZsPO�)G���+O;79I+-3,(KI+3H/b3�� <Ac3A�C*=���kO�<3��45��hA��C* [sPO�)G���+O;79I+-!�)* �/�����<79- ���CA?G�������-�.3<Y0��(�:32��hGK*.7#� ������g78-4A��C3��(�:AlsG��C3,3��4I+-4� �e7�� & ��26�?7#�V/�G+* )O���� ��79I+-:�.*,(K3��PB��C*�� & ����)3,32��� � & cG+* )3 �����!�9>�� & c>@(K-4-�3,G��� �.*H(+A �9>� & * d7<�.35�����+3��4O�)* <O & <*�cp ����<-:(+O���+5 �������C*,*�����5�C*'�������CA?GK-��� l* <\E(��:* )A!��C�,3<Y_5;7rB�<O�O�<3 �:5��+3)Y5�79DV/ �:A?GK-�<A���-�.7�������+3<Y¤7#�+O ���#�������CG�<*.7<�����K5jG & /N3����<79-"��V6��4*����+A���-�.3=�9i�<*����+57)-�����.*��CA?795��� ��������-� <*H>�)* �����8YG<79*�� & \E(;79D�<3<Y^A?793,3��:6��G��rB�)*(�C(���785�<3)Y`7#�+O�3 � ���_Q ¡ (+*�� & <*HA!�C*�9Y.� & l79-:A!�C3)�F(��bs7d6����:O;79I+-0/:�<*��� ���d78-+* �C-<36�9> G���9G+-� � & * �C(+5 & �C(��6� & <3 z3H/b3�� <Ac3�7#�KO%�� �PB��C*HDE3�*.7#�:3 o3 )* ��C(+3��CG�)*.7ws������;79-K\b(�<3�� �����K3Tp )3,G�����479-4-0/x*�<-47�����+5�����-�)3,3Ms � & 7��NsPG�<*M>��������+O��:6��:O+(;79-:3�B & �XAg7d/UI�oO��43 & ����)3��<YA?79-�������9(+3<Y1�������CA?G��� ��-�dY>�:A?GK* �CG�<*H-:/%�,*.7#���<O�Y;O��43����-��)* <3)��)O_Y �C*'B & �gA��45 & ����e7#�V/jBL7d/aI� & 7d6�O��0i.)* ��-�,-:/�>@*��CA & ��B � & 2/ B��C(+-4O�I�721NG����� <O � �"7����4����7�� 793H3,(+A�<O�G�<*H>�����lB��C*,-:O_Q %'& )3 7#�+O�A?7#�V/ �#� & <*5�����+3��4O�)*.7�� �����K3A� & 7���79* 7�;7<�.(+*,79-4-0/"3H(+I+3H(+A!)O (��+O�<*4�C(K*A���#� ����� �9>u5����<*,79-0s� � <Ok3,(+*M61�06879I��4-��P/gAg79D�'� & xGK* �CI+-<Ac3u79O+O+*�<3,3�<O & )* 221��.*�<A�<-:/ � & 79-4-��+5���+5+Y��:A?G��C*)��7#�-�dY�7��+O���:A!)-:/9Q

%'& =� & 78-4-���+5� & <* (�:3�����O��:� & JI�)3��'B�(�d7#� ���&� & F>��C*�<3 �d79IK-�F>@(��,(+* 8Y;7#�+O7���:� & 79*.7#� ��)* � � 3�� <G+3�� & 7��WAU(+3��FI�5�.79D#��F� & 7<�FB��4-:-G��;79I+-x(+3�� �j7#� & �)6#UI� � � <*F3M/N3)��)A?3=��,� & xA!�C*�xO��:3��.7#�-�>@(��,(+* 8Q %'& <* (�:3�3�� �4-4-�7�-��#�����l-�<79* �a79I��C(��o3H(+*H6��06978I��4-��P/?7#�+O & �rB � �l7�� �.7#���7�/�'O�)G���+O;79I+-0/CQ � & �CG�=� & 7<� � & �:3'* <G��C*)�uB��:-4-¤I��7�3 �:5��������d7#�-�o3�� <G9���7� & 7��uO��4*����� ������Q� �N>��C*��,(��;7�� <-:/9Y-� & u\E(�<3)��>��C*�3 �:A?G+-������P/x7#�+O%<793H/?7#�K3HB�<*,3��43�G�)*H68793��:6�8YKI+(1�f6#<*H/cO�� ���<(+-/��� �

���9AUI;7��<Qz];�,� & �43z* )G��C*)�dY�B�U7�� � <AcG��E� �j79O+OK* <3H3 � & xO��<G�<*��:3,3,(�<3F*�d79-�43�� ���<79-4-0/v7#�KO,���&��+3,G��4* AU(�� & 5C*�d7�� <*o(��+O�)*,3)��7#�+O����+5��9>G� & �C3�(�43,3H(�<3)Q

)�*��

Page 154: Practical Architectures for Survivable Systems and Networks (Phase

���� � � �� � � � ! � � ' � ��!� � ��$ '�� ��� � '��#$ �

�F(+*xA?7#��"*�����9A?A���+O+7�������+3X79* ?3,(+AcAg78* � � <O & <*�9Y�* ��d79G���.(K-=7�� ���+5 � & gR$1���<(�� �:6#93N(+AcAg79*M/CQ3NG�������>�O��:* �� ������+3�>��C*'*�<3 <79* � & 7#�+O�O�)6#<-�CG+A���-�z79* O��:3 �<(K3,3 )O,��,3����� �������KQ �NQ* � AU(+3)� )3���78I+-��:3 & 5����)* ���A��43H3 ����jA!�bO�)-43X{ 31���� ����� �NQ0����� & 7�� �<7#�kI��* d78O��4-0/%��7��4-��9* <O&� �3HG�������>�o3H/b3�� <Ac3<Y+7��+O?O�)6�)-��CG?G+* ����)3,3�<3fB & <* )IV/!� & �C3 oA��NO�<-43"�<7#�gI�o(+3 )O%��!26978-4(;7�� ���+5� & �79O�)\b(+7#�)/ �9>�* )\E(��4*�<A���-�.3)Q

* � 'AU(+3)�"<3)��79IK-��43 & G+* �#� �#�P/bG����<79-K*�<\E(��:* <A���-�,3�>��9*T3,(+*M6��:6879I��:-���P/X7#�KO��/�.3T3H(+I�� ��+O�)O?GK* �CG�<*Zs� ��)3�� & 7����d7#�vI�uO��4*�����,-:/c79GKG+-��<O4���U3M/N3)��)A�O�26�)-��CG+A���-�,3'7#�+O?G+* ���<(+*�<A���-�.3)YK3H(���������-�.-:/O����7��4-�)OjI+(�� ���#���r6#<*,-0/ �����K3��.*,7#�������+5+Q

* � 'AU(+3)�SO� �>��u>¥79A��4-��)30�9>¤3H/b3)��<A 7#�KO�����PB��C*,Dl79*�� & �� �� �.(+*�<36� & 7��S78* ���� & <* ��-�.-:/x* �CIK(+3��<Y7��+OaO�<A����+3)�.*.7<��=� & (�:A?G+-<A���-��78I��4-��P/4�9>G� & �93 �79* � & �������,(+* )3<Q

* � aAU(+3)�?O�)6�)-��CG ��)B ����PB��C*,D�7#�KO O��:3��,* �4IK(���)O 3M/N3)��)A GK* �#� �1���C-43l79GKG+* �CGK* �=7<��v>��C*:� & O�)6�)-��CGKA!��C� �9> & �:5 & -:/?3,(K*H6��:6879I+-9Y;3���<(K* 9Y�7#�KOk*�<-��479I+- ���N>��C*,A?7�������%��K>@*.783��.*H(����,(+* )3<Q

* � SAU(+3��$O�<3��45��x7#�+O2�4AcG+-�)A!��C�G�CG���bsP3H/b3)��<A#79*�� & �� �� �.(+*,79-1���CAcG�������-�.3G� & 7��$79*��)3,3 ��-���=78->��9*J* �CI+(K3��X79* � & �������,(+* )3XI+(1�5�����J/���X* <79O��:-:/�7d687#�:-=79I+-A��� � & lAg79*HD# �.G+-47#��8Y`B & ��� & B & �����CAcG��C3�<O'���C5� � & )*0�<7#�U3,7����:3H>�/3��,* ���K5F* )\b(��4* )A!��-�.3�>��9*^3H(+*H6��06978I��4-��P/7#�KO5���-� <* �9G�)*.79I��:-��/�P/CQ

* � WAx(+3���<3��.79I+-�43 & 7x-��:I+*.79*M/4�9> O�)A!�#�+3��,*.79I+-0/c3 �C(��KOjG+* ����)O+(+* )38� & 7<�8��+79I+-� �.*H(+3��PB��C*�� & /3M/b3���)A?3 � �'I��I+(��4-�?�C(�� �9>N-�)3,3?�,*,(+3)�PB��C*)� & /(���9A?G�������C�,3<Q %'& �43 �:3?� & "��������<G��G�9> � � � ��� � � ���$���������� � ��� � �����B & ��� & B�'21NG+-�C* (���&� & �43o*�<G��C*��<Q

* � oAU(+3)��)3���78I+-��:3 & 7#�+O%�����+3��43�� ��-�.-0/l(+3 u3 �9(��+O%�)*H/bG�� �C5C*.78G & ��� ���N>@*.793)�.*,(����.(K* <3�>��C*S79(�� & ��bs� ���<7�������_Y���<*)�����>�d7�� �79(�� & �C* �/����)3<Y;7��+O �������+O���-���479-��/�P/CQ

* � �AU(+3����>�+O�B�7d/b3E� �%������C(K*.795�'���9A?A�<*����=78-_3H/b3�� <A O�)6#<-�CG�)*,3 ���������)* d783 2� & �3,(+*M61�06Vs78I��4-��P/CYb3 ��<(+*���P/9Y�7#�+Oa* )-��=78I��4-��P/:�9>G� & ��4*L3���7��+O;79*HOkG+*��NOK(����,3<Y>�����<-4(KO����+55������C(+*.785����+5A� & <A� �4<AUI+*,7#��A��C* J5#�1�bOj* )3 d78* � & 7��+OkO�)6�)-��CGKA!��C�u*�<3,(K-�.3)Q

* � FAU(K3�� �����+3 �:O�<*)Y;793o7#�a78-��)* �;7<���:6#E� ��G+* �CGK* �� ��79*M/%�)-��C3�<ONs¢3 �C(K* ��J3��9>@�PBL79* 8Y�� & JO�)6�)-��CGbsA���-�L7#�+Ov(K3 ��9>`3��C(+*���2sP7d697��4-=78I+-�o3 �8>@�PB�79*�F7#�KO&�����+GK* �CG+*��� ��79*M/!��-��<*M>¥7#��)3<Q � -� & �C(+5 & � & �:378G+G+* �C7#� & O���<3E���#�������)3,3,79* �:-:/k-�d78O ���g3,(+*M61�06879I+-��3H/b3)��<Ac379-:- IE/ ��,3 )-:>ZY��� & 793 ����C*HA!�C(K3G��#� ��-���479-¤B & ��,���CAUI����<OjB��� & ��� & )*8���� & ���4\E(�)3<Q

* � cAU(+3��XG+*���6��:O�c>��9*�A��� & 7#���43HA?3>��C*=�.*H(+3��PB��C*)� & /�O��43��,* �:I+(������� �9>��,*,(+3)�PB��9*�� & / ���bO�Up����<-:(+O���+5U* �9I+(+3��uA��CI��:-�����NO�8Q

* � FAU(K3��o* �>��7#�KOjAg79D�JG+*.7�������d79- � & =���+5�����+5�y�t )i��C*��,3�>��C*�A������� �C* ��+5+YE7#�+79-:/ � ��+5+Y7��+O *�<3HG����KO����+5 ���h3H/b3)��<A 7#�+OB�� �PB��C*HD�7#���CA?79-��<3)Yf7��+O 5����<*,79-�� � &� & <A >@*��CA A�<* )-:/��-�.*,(K3 ���#�NsPO� �����������v3M/N3)��)A?3)Y;3 �A� & 7��8� & )/j78O+O+* )3,3u7UI+*��V79Oj*.7��+5���9>^3H(+*H6��:6879I��4-��/�P/VsP* )-=7�� <O� & * <7��.3)Y�����<-:(+O���+5�* )-��=78I��4-��P/�G+*��CI+-�)A?3)YS>¥78(+-�MsJ���9-�<*,7#����&���r6�)*.795#�>¥7#�:-4(+*�<3)Yf7��+O �<-=783,3 ��d79-����PB��C*,DjA?7#�;795#<A���-�dQ

* � �AU(+3)�jI��79I+-� ����O�)6#<-�CG 3H/b3�� <Ac3 � & 7���79*�nA��C* F<793 �:-:/ ����� �;5C(+*�<O 7#�+O Ag7��;795�)OB��/� & �9(��oG+-=7������K5:211��)3,3 �06�XI+(+*,O���+3 ���a3H/b3�� <A 79O+A������43��,*.7�� �C*,3)Q

)�* �

Page 155: Practical Architectures for Survivable Systems and Networks (Phase

* � �AU(+3)�kGK(+*,3H(��*�d79-�43�� ���n*�<3�d79*�� & 7#�+O O�)6#<-�CG+A���-�e*�<-47�����+5 ����G+*.7�������d79-J3M/b3���)A �43Ms3H(�<33H(�� & 793=���CAcG��C3,79I��:-���P/9Y�A?7#���-�.7#���;78I��4-��P/CY 26��C-06978I��4-��P/CY����-��)* �CG�<*,79I��:-���P/ � & 7���79*�l79-43��3)�.*����+5C-0/"I+793 )O � & ��9* �� ���<79-4-0/CQ 31�931�� ��������KQ ��>��C*U3��CA!g3,G�������>�vO��:* ���������+3x>��9*x* )3 <79* � &7��+OaO�)6#<-��9G+A!��-�dQ

* � nAU(K3�� �>�+O~BL7d/N37� ��O��43H3 <A����+7���9� & ��������)G��.3 �9>(� & �43v*�<G��C*��gB��4O�)-:/CY �����<-4(KO����+5 ���Ns5+(���������+5 � & &)O+(��<7������� G+*��1��<3,3�<3l7#�KO �4AcG+* �r6�)O �.*,7#�������+5+Q"{ 31� � G+G���+O��¦1 � >��C*x3��CA�3H(+5C5�)3�� �����+3)Q��

��� � � � � � $ �� � ! � � ��� � ��� � � � ! ' � ��$ � ' ��� !�

31��������� �NQ0� � �����+3��4O�)*,3�� & k* �C- �9>*�<3�d79*�� & 7#�+O O�26�)-��CG+A���-�<Q %'& �:3?3����� ����� �C(��.-����)3?3��CA�3,G�������>��y�t#O��:* ���������+3�>��C*8� & J>@(��.(K* 9Q* t� �>��8YCO�)6#<-�CG_Yb7#�+O:�:A?G+-<A���-�$7W3 �6�9>�* �CI+(K3��"�� �PB��9*,DC���+5G+*��#�������9-430� & 7��$3H/b3�� <A?7�����d79-:-:/7��+O ���CA?GK* & ��+3��:6�)-:/ ������CAcG;793,3�� & �����<3H3.79*M/ * )\E(��4*�<A���-�.3g>��9*?3H(+*H6��:6879I��4-��/�P/�7#�+O ��,33H(+I�� ��+O�)O~7����.* �:I+(�� <3<Q { � eI�<-��)6# � & 7��?I���d79(K3 ,�8> � & ,�����<* <793 ��+5$���;79O�<\E(;7#�2/ �9>�� & [11�43�� ���+5�G+*��#�������9-43:����-�45 & �:�9>WAg783,3 �06�aI;7#�KOKB��4O�� & ����<*�d793�<3)Y����bO;7d/ �|3lG+*��#�������C-'Ax(+3��cI�*�)6��43��� <O 7#�V/EB�7d/CQ %'& (+3<YFB�h3��.*����+5C-0/ (+*H5�F��78D���+5�79OK687#�-��785� �9>2� & 7�� �CGKG��C*)�.(�����P/ � ���+3,(K* (� & 7��o3H(+*H6��06978I��4-��P/!�43 ���#���:5����C*�<O ���7� & G+* ����)3,3 �9>$GK* �#� �1���C-_A��NO�)* ��� � 7�� ������Q��

* R�3)��79I+-�43 & 7vO� ������ �:6�x3 ����9>S5����)* ��x3H/b3)��<A�* <\E(��:* )A!��C�,37#�+O )-=79I��C*.7<��5�#�,� & �GK* ����<3H3�8>oAg79GKG����+5kA!�:3,3������"* <\E(��:* )A!��C�,3:���-���n79G+G+*��CG+* �47���?3,G�������>�v3H(+I+3���.34�9>o5#���)* ���g* <\E(��:* [sA���-�,3<Q�R�3��.79I+-�43 & A!<793,(K* <3f>��C*�O��� <*,A��������+5(� & W79O�)\b(+7#�)/!�9>?� & �C3 z* )\b(��4* )A!��-�.3�7��+O%� & 78O�<\E(;7#�2/F�9>�3H(+I+3�<\E(���-�2�4AcG+-�)A!��-��7�� �����+3)QJq�79*H*H/9� & �:3WG+*��1��<3H3=�C(��=[1KGK-�������,-:/j>��C*z3 )6#<*,79-3HG�������>��79G+G+-���d7<�����#�+3L3H(�� & 793 � & % 7#� ����d79-_];�-� <* ����dQ

* t�)3 �:5���O���.7#�4-<O �CG���bsP3H/b3)��<A 78* � & �/���� �.(+*�<3J>��C*J*��CI+(+3)�A!�CI��4-�2���bO�9Y^7#�KOhO�)6�)-��CGhG+*��#���8s�P/bG�(�4AcG+-�)A!��C�.7�������+3)Q

* R�3)��79I+-�43 & 7:���CA?GK* & ��+3��:6��>��C(��+O+7�������v>��C*'A��CI��4-����bO�8Y;3,G�����0>�/����+5������<3H3.79*M/ ��K>@*.783��.*H(��2s�,(+*.78-f*�<\E(��4*�<A���-�.35��� �CG�<*.7<�����K5e3H/b3)��<Ac3<Y�I+*��rBo3 <*H3c7#�+O 3�<*H6#<*H3<YSI��C(��+O;79*M/�G+*��#������ �����_Y����PB��C*,DjG+*��#�������9-43<YNG+* �95C*.79AcA����+5U-47#�+5C(+795�<3)Y+3H/b3)��<A ���CA?G��C3��������_YN7#�+O9�#� & <*�>¥7#� ���C*H3<Q

* t�26�)-��CGh3,(+IK3H/b3�� <Ac3�7#�+O ���CAcG��#����-�.3'� & 7<�2�<7#��I�c* d78O��4-0/ ���-��)5C*.7<��<O�B��� & ��� � & !�CG���bs3M/b3���)A 78* � & �/���� �.(+*�<3)YX3H(�� & 793eI��C(��KO;79*H/ �����-�.* �9-4-�)*,3)Y=����PB��C*,D 3 )*H6�)*,3)YU79(�� & ��-� ���d7<�����#�3�<*M6�<*H3<Y�7#�+O�A��CI��4-2sJ���bO�W3�<*H6#<*H3F7#�+O9���#�+3��,*.7#���<O9211��)(�������9�<-����-�.3)Q

* q��#�+O+(�� �U* )3 <79* � & ���"3,G�������>�j793HG�����,35�9>o5����<*,79-�� � )O�O�)G���+O������9Y�O�26�)-��CG���+5n7k5����)*.79->@*,79A�)B��C*,D�>��C*j7#�����CAcA��NO;7<�����K5 ��%���~3M/N3)��)A O�<3��45�� 7#�KO O�)6�)-��CGKA!��C�<Q %'& �:3v* )3 <79* � &3 & �C(+-:O�79O+O+*�<3H34� & aA!�� & 7#���:3,Ac3A��E(+A�<*,7���)O ��B31�� ������ �CQ��bQ �NQ � -/� & �C(K5 & ��x3 & �C(K-4O ���Ns�)-4(+O��� & �<(+*H* ��-�,-:/cG��9G+(+-=78*"���#��������9>�Bo*,79G+G�<*,36� & 7�����-����KO!����A?793,D'5�7dBo3f7#�+O!��6#<*����CA�7<� ��7���Db3)Y6���3 & �C(+-:O ���#�4�45#���C* ?3 �CA�7�9>�� & 7�#� & )*UG+*��CA!�:3 ��+5nA��� & 7#���43,Ac3x>��C*5�� & 7�������+5�,*,(+3)�PB��9*�� & ����)3,3<Qg]J�X3 & �C(+-:O�78-43 � & �#��<3)�.-:/h78O+O+* )3,3(� & 7<��>¥7����(� & 7<��Bo*,79G+G�<*(���� & ���C-�C59/ �:33H(+3 ��<G�� �4I+-=���4���CAcG+*��CA!�:3 W>@*��CA�B��/� & ���7#�+Oa>@* �CA�I�)-��rBQ

)�* �

Page 156: Practical Architectures for Survivable Systems and Networks (Phase

* q��#�+O+(�� �* <3�d79*�� & �#�hGK* <O������.79I+-U3,(+IK3H/b3�� <A ���9A?G��C3 �/������_Y�IE/eB & ��� & � & :���CAcG+* & ��K3 �:6#*�d79-�43)�����SG+*��CG�)*�� ��<30�9> � & L* <3H(+-� ���+5 ���CAcG��93 <O�3M/b3���)A �d7���I��O�<* �06�)O_Q�q & 79*,7#��� <*�� � LG+* �CGbs)*�� ��<3H�9>����-��)*H>¥7#��<3^3,(�� & � & 7��G� & ����9A?G��C3 �/������+3 O��E���#�G�d79(K3 �7��E/�78OK6�)*,3 L3 �4O��2i.����.3)Q %'& �:3B��C*HDnAU(+3)�(������CA?G+793,3=� & l>@(K-4-$3HG�����,*,(+A �9>f3,(K*H6��:6879I��:-��/�P/k*�<\E(��:* <A���-�,3<YG���#�L§H(+3)��7j6#<*M/�+79*,*���B I;7#�+O?793 & 793�I����!� & �<793 ���:� & oG;793��<QT];�cG;79*�� ���)(+-=79*)Y-���Ax(+3���������CAcG;793H3f5����<*,79-0s� � )O�O�<G���+O������c*,7�� & <* � & 7#�?§H(+3)�3��.*���� �JO�<G���KO������4����7��Hs¢-�<793��MsZ793ZsJ�.*H(+3��PB��C*)� & /,���CAcG��8s����-�.3)Q$]J��AU(+3��$79-:3 �oG+* �r6��4O��[1KGK-�������H�����+O��/�����#�+3 � & 7��^AU(K3���I��3.7<���43 �><OXIV/2�:A?GK-�<A���-�.7�������+37��+O ���+O���d7�� & �rB � & �C3 (�����+O��/�����#�+3 �d7#��I�F6�<*����>)Oap 3)��7�� ���d78-4-:/!�C*'OK/��;78A!��d79-:-:/CQ

* t�26�)-��CG&� �1�C-:3f>��C*�� & J3)��79*HDg3,(KI+3 � ����+54�9>G�CG�<*.7<�����K58sP3M/N3)��)A 7#�KO�A��4OKO+-�2B�79*�z>@*,79A!2B��9*,DE3� & 7��'�d7���I�4�.7#�4-�C* )O ����3,G�������>�c3,G�����479-0s¢G+(+*HG��C3�l* <\E(��:* )A!��C�,3<Y^B��� & 79(�� �CA?7���)O"3M/N3)��)A5#���)*.7�� �����_Y�*�<3,(K-����+5�����3,G�����=79-¦sPG+(+*HG��93 �3H/b3)��<Ac30� & 7��^3 <79Ac-�<3H3,-0/F* )A!�r6#L79-:-#� & f(������)O�<O>@(������ �����;78-���P/�>@*��CA � & j5����<*,79-�>@*.79A�)B��C*HD 7#�+O �����+3 )\E(���-�.-0/�3��.79*,DE-:/�* )O+(���7� & 7���C*H* [s3HG��#�+O����K5n6N(K-���)*.79I��:-��/����)3<Q ¡ �C*521K79AcG+-�8Y�7 �;* 2B�79-:-8�C*�7n*��C(�� <*U3 & �C(+-:O & 7r6#aI;79* [sPI�����)3�9G�)*.7�� ���+5l3H/b3)��<A 3 �8>@�PB�79*�2� & 7��zG+* � & �4I��/�.3oA!�93�� �9> � & & �45 & s¢* �:3,Dv(+3�<3��8>T5����<*,79-0s¢G+(+*,G��C3�3M/b3���)A?3�{ � <IVB�78* 9Y ��)-��� �dYo7#���#�E/bA��C(+3g>@�,G_Y 2s¢Ag7��4-'B��� & 79*,I���.*,79*H/�7<� ��7�� & A!��-�.3��[Q � 3Zs3��1���=7�� <O �����C-43l3 & �C(+-:O ������CAcG;793H3!� �� & ���:\E(�<3g>��9*���+3,(K* ���K5 � & k3��C(��+O���<3,37�8>����#�C�,* �C-:-�)O�������;59(+*.7�� �����jA?7#�;785�<A���-�u7#�+O�OK/��;79A����J*���������;5C(K*.7�� �����_Q

* t�26�)-��CG ��C� <*��CG�)*.79IK-�n3M/N3)��)A?3j>��C*vA������/���C*����+5KY'7#�;79-0/ � ���K5+Yu7#�+O~* )3,G����+O���+5 ����3M/N3)��)A7��+O&�� �PB��C*HDg7����CA?79-��<3<Y-������9A?G;783,3 ��+5U3���<(K* ��P/9Y+* )-��479I��4-��P/9YC7#�+Og5����)*.79-� � <Ov3H(+*H6��:6879I��4-��/�P/� & * <7��.3u7#�KO9�)-=793H3 ��d79-?����PB��C*,DaA?7#�;795�)A!��-�dQ

* R$1NG+-�C* � & �G+* ����)3,3G�9>NOK/��;79A����T3M/N3)��)A �������+5C(+*.7<�����#�'���CAcG;7����:I+-�^B��� & � & �3 )-������)OX3H(+I+3����8>o* <\E(��:* )A!��C�,3<Q %'& �:3U3 & �C(+-4O ����<-:(+O�?I��#� & & (+A?7#�NsPOK* �:6#���7#�KO�79(����#���CA��C(+3x*���������;5C(bs*,7�������_Q %'& XG+* ����)3,3��9>S78-��)* ��+5?3M/b3���)A �������;5C(K*.7�� �����+3oB��� & �C(��W79OK6#<*H3 <-0/F���CA?GK* �CA��43����+53H(+*H6��06978I��4-��P/k3 & �C(K-4OhI�?7���-�<793���G;79*)���479-4-0/n79(1���CA?7���)O_Y B��� & 7aA!�¦1��.(+*�:�9>8�������;5C(K*.7�� �����Ns� �4A�v7#�KO�*,(��Ns ���:A!!� & ���DE3v7��+O�3 )-:>=sPO��=795����C3�� ���!� �� & ���4\E(�<3:� � ��+3H(+* 7� & 7��:� & j5#�:6����* [s\E(��:* )A!��C�,3������-����E(�=���lI�3,7����:3 �>)O_Q

* q��#�+O+(�� �k*�<3�d79*�� & ��� OK/��;78A!���79O;79G��.79I��:-���P/B�9>X3H/b3)��<Ac3 � & 7��aO��1)39���#� ���CAcG+*��CA!�:3 F�9*3�<*����C(+3H-:/jO��4A������:3 & �r6�)*.79-:-^3M/b3���)A�7��+O ����PB��C*,D�3,(+*M6��:6879I��:-���P/9Q � -� & �C(+5 & OK/��;79A�����79O+79G��Hs78I��4-��P/'�43�3��4A��4-=78*0�����������<G������OK/��;79A����'*���������;5C(K*.7�� �����_Y-�/� & 793�6879* ��C(+3�793HG�����,3�� & 7��6���<O� ��I�F���#�+3 �:O�<*�<O+�� � & ��4*��rB��~-��45 & �<Y�G;79*)����<(+-479*,-0/ � & �93 ,��V6��C-061��+5 � & n3)��79I��:-��/�P/ �9>�79(Ns� �����CA��C(+3S7#� ������+3����4���4A�<36�9>_O+(+* )3,3)Q � �rB�26�<*)Y+* )3 <79* � & ��gOK/��;79A����u79O+79G���78I��4-��P/U3 & �C(+-:OI�=�����C*HO����;7<��<O �)-��C3�<-:/?B��� & � & (�43,3H(�<3���E6#�C-:6#<O9���aOK/��;79A����=�������;59(+*.7�� ������Q

* q��#�+O+(�� �z*�<3�d79*�� & ��� & �rB � ���:A?GK* �r6�(d783 (�9>�(+3 '�9>0���CAcG+-�[1j3M/N3)��)A?3)Q* q��#�+O+(�� ��* <3�d79*�� & �#� & �rB � �=�4AcG+* �r6�L3H/b3�� <A �CG�<*,7�������_Y�����<-:(+O���+5W*�<O+(������+5�� & �<(K*,* ��-�.-:/�)* �/�����<79-�O�<G���+O������2���7� & 3 & �C*��u3H(+G+G+-0/7�9>021NG�)* ������<Oe3M/b3���)A 79O+A������:3��.*,7����9*,3<Q

* t�26�)-��CGg7#�+O&[1KG�<*��4A���-�LB��/� & ��<3)�.I�<O7��E6��:* ���+A���-�,3�� & 7<�LG+(K*,3,(� � & zO��4*��� �����#�+3��9(��.-����)O78I��r6�8Y0����<-:(+O���+5a* �CI+(K3������>�d7<�����#�$�8>8�CG���Ns¢I��d1h3��9>@�PB�78* 9Y�5����<*.78-�� � <O�O�)G���+O������vA��� & 7�s���43,Ac3<Y`OK/��;78A!���* ��������;59(+*.7�� �����$����*�<3,G����+3��� �kO�������� <O�7�����7#��DE3)Y$7#�KO"3��,���_Qe{ 3��%31��[s� �����a�NQ �NQ �

)�*��

Page 157: Practical Architectures for Survivable Systems and Networks (Phase

��

� � � ��� ��!� � � � $ ! � � � $ � � � � � '���� � � $ � � ! ����� ��� ��� � �$� � ��� � ��� � � � � ��� � � � ��� � � ��� � � � � � ��� � � � ��� � � ��� �*� ����� � �*�X��� � �A����� � ���� � � � � � � ��� � ��� �#��� � ��� � � ��� � � � � � � � � � � � � � ��� ����� � � �:� � ����� ��� � � ���M������� ����������� ���(� � �������� � � ���&� � � ��� �#� � ��� � � �_� ������ � � �� � �� � � � � � ��� � � � ��� � � � ��� � � � ����� � ��� � � � ��� �(� � � � ���������� � ���(� � � � � ����� � � � �\� � � ��� ��� �����'� � ������ �$��� � ��� ���$����� � � � ��� ��� � ��� � � � � � �(���_��� � ���� � � ������� ��� D��� � � � ��� � ��� � �(� � ���(� � � � � � ��� � � � ��� � � � � �#� � �������� � � �$� ������ ���$�D�������*��� � � � ��� ��� � ���H� ���6�������(� � ����� ��� � � � � � ��� � ��� ��� � � � ����� � ��� � ��� ��� �1���$�D�������*��� ��� � � �� � � ��� ��� ��� � � � � � � � � � ��� � ��� ����������������� � ��� � � ��� � ����:� ����� � � � �����*� � ����� ��� � � ��� � � ������� � � � ��� � � �#� � � � � � � � ����� ����� �(� ��� � � ��� �� *�� & (K*�31� & �CG��� & 79(�<*<Y¤R$11��<*HG���)On>@* �CA�� � ����� � � ��� ��� � � � � �Q��� � � � �T�r� �N�CY>�����<-4(KO�<O�� � ��������� � � � ����� � � � �������(� � �� <O��/��<O IV/ t� � ���� ��QS�$79*HD#<*)YE31�<*��4I���)*,3)Y'mE2B����C*,D�Y�d�V�9�KYbB��� & A������9*�A!�bO�)* ��� � 7�� �����&�8>D� & (�,*.7#�K3,-=7<�����#�vIV/�� � mXQ

0e7#�V/�-<3,3����+3!�d7#� I���� 59-�d7���<O�>@* �CA [1NG�)* ��������B��� & G;783��?3H/b3�� <A O�)6#<-�CG+A���-�.3)Y'I��#� &3,(�����)3,3M>@(+-T7#�KOk(��K3,(�����<3H3H>@(+-�Q %'& <3�5[1KG�<*��������)3 �d7�� & )-4G�(+3������d79-�4I+*,7����� & �79G+G+*��CG+* �47������<3H3�9>G� & J6879*����C(+3'GK* �������4GK-�<3L3 �d7<� ��)* )O � & * �C(+5 & �C(���� & �43'O����<(+A���-�<Q

%'& 'B��C*,DA�8> � ��+*M/l�0 �.*��C3,DC��}|�8� �NYE�9�9�w�^{¥7(���:6��4-1��+5#�����<*�7��StF(+D� � ���06�<*H3 �/�P/+� �:3 ���#� )B��C*�� & /9Q�0 �.*��C3,DC� & 793 �8>@����7�9I+3 )*H6�)O9� & 7���B�=����+O&����-d79*��v6�<*M/j-��/� �,-�o>@* �CA �C(+*�3H(�����<3H3 <3z7#�+O7� & 7���B�5����<*,79-4-0/2�<7#�U-d79*��UAU(�� & A��C* S>@* �CA �C(+*^>¥7#�4-:(+* )3<Q � �K>��9*��.(��;7���)-:/9Y#� & �21NG�)* ������<3�O����<(+A���-� <O21�� ��+3��:6�)-:/lIV/lm <(+A?7#���k}�� �9�w��3H(+5C5�)3��6� & 7��"� & '3,79A�'A!�:3���78D#<3"� ��+O:���I�oAg79O�8�r6�<*f7#�+O4�r6�)*795V7����?p G;79*)����<(+-479*,-0/%��7���CAcG+(�� <*Ms¢* )-=7�� <Oa3H/b3�� <Ac3<Q

�E)* W79* J7>�)B ���#���<-:(+3 ����+3<Y1���?G;79*�����)A?G�<*�<OjIV/?BL7�� � & ���+52� & ���<5V7�� �:6# 21NG�<*��������<3 ��%� & ���Ns¢-����gy��43HDE3 ¡ �C*,(+A�YT7��+O ��� G+79*��U>@*��CA & �45 & -��:5 & �����K59� & &���#�+3��,*,(�� ���:6#a793,G��� �.3:�9>o3��CA�vG;793)�3H/b3)��<A 2i.�9*��.3)QT]¢>H3�� & �CG��� & 78(�<*f7#�+Oc�0 �.*��C3,DC��79* u793T>@(��+O;79A���-��78-4-:/2���9*,* ����f7936���79G+G�d79*H36� & )/79*�9Y+B��Ax(+3��u-�<79* �aA��C* F>@*��CA �9(+* 21NG�<* ������<3)Y¤5����bOa7#�+O�I;79O_Q* y�<\E(��:* )A!��C�,3fAx(+3��fI�o3H(���������-�.-:/����C*,*�����<Y1�����+3��43�� ��-�dY����9A?G+-�� 9Yb7#�+O?G+* ����43�<-0/l3,G�������><O�Y>@*��CA � & e6�)*H/ I�)5����������+5 �9>7�G+*��1�)(+* )A!��-�7�C*cO�)6#<-��9G+A!��-�dQ y�<\E(��:* <A���-�,3vAU(+3)�&��bs���CAcG;793,3E���#�f§H(K3���� & A�<*��� ���d78-`>@(������ �����;78-�G+*��CG�<*�� ��)3l{¥3H(�� & 793F3,(K*H6��:6879I��:-��/�P/CY�3 ��<(+*���P/CY`7��+O*�<-�=79I��:-��/�P/+�[YCI+(��'79-43��5�CG�<*,7�������;79-�* )\E(��4*�<A���-�.3�{@3,(�� & 793����-��)* �CG�<*,79I��4-��P/9Yb*�<(+3,79I��:-���P/9YK7��+OG�<*M>��C*,A?7#����r�[Q

* %'& g79*�� & �� �� �.(+*,79-�>@(��+O;79A���-�.79-43�AU(+3)�xI�?3��C(��+Oh>@* �CA � & l6�<*M/�I�<5#��������+5+Y^7#�+O"O�<A����Ns3)�.*,79I+-:/ �<79G;79IK-���9>'3.7<���43M>�/����+5 � & ?5��:6#��"* <\E(��:* )A!��C�,3<Q %'& gO�<3 �:5�� AU(K3��XI��� & �C*��C(+5 & -:/3HG�������><O_Q�3N(K*H6��:6879I��:-��/�P/c7#�+O ��,3�3,(+I1����KO�<Ok* <\E(��:* )A!��C�,3�{ ������79I+-0/g3���)(+* �/�P/a7#�+Ov>¥79(K-�8� �C-0s)*.7#����r��AU(K3��uI�JG+79*�� �9>G� & (�r6�)*.79-:- ��������<G1�����#��*,7�� & <* � & 7��k*���.*���������<Ok78>@� <*8� & >¥7����dQ

* %'& &�4AcG+-�)A!��-��7�� �����h3��,*.7�� <59/�AU(+3��UI�v*�d79-�43)�����8YT7#�KO >��C-4-��B�<O �����+3��43�� ��-�.-0/ � & * �9(+5 & �C(1�(��+-�)3,3oAg7r§��C* 5�7dBo3z79* (�4O���-�����><O�7#�+O9���9*,* ���� <O_Q

* %'& '�:A?GK-�<A���-�.7�������g3 & �C(+-:OkI�O�<A����+3)�.*.78I+-:/%�d79G;78I+-�=�9>�3.7<���43M>�/����+54��,3'3,G�������>�<7�������_Q* %'& J3H/b3�� <A 79*�� & �� �� �.(+*�7#�+O&� & =��-���:* FO�26�)-��CG+A���-���2/1�)-�JAU(K3��o7#�-� �����:G;7�� E� & =���)O+3 �9>26��C-:(�������;79*M/a5C* �rB � & Y�7��+OnAU(+3)� �.79D#U3��45������>�<7#�-�F79ON697��C�.795�2�9>TB & 7�� & 793FI����n-�<79* ��<OF��*�<3�d79*�� & 793`B�)-4-b793`B & 7��0�d7#�XI�S-�<79* ��)O�>@*��CA 21NG�<*�����������XO�)6�)-��CG����+5 �CG�<*.7<�����K5u3M/b3���)A?3)Y

)�*��

Page 158: Practical Architectures for Survivable Systems and Networks (Phase

����PB��C*,DE3<Y�78* � & �/���� �.(+*�9Y;G+*��#�������9-43<Y1�<*M/NG1���C5C*,79G & ����4AcG+-<A���-��7�� �����K3<YE3 �9>@�PBL79*�'��+5�����)* ���K5� �1�9-43<YK7#�+O9�#� & <*'O��:3 ���:G+-����<3)Q

%'& �>��C-:-��rB����K5��� <A�� � 7<�����#�2�9>¤-�)3,3����+3�-�<79* ��<Oc79AcG+-����><3�3 �CA� �r6�<*,79-4-K3��.*,7���)5���)3T>��C*�7#� & ��)6���+5& �:5 & -:/?3,(K*H6��:6879I+-3H/b3�� <Ac3W7#�KO9����PB��C*,DE3<Y�I+(�� �:3o79-43��?78G+G+-���d79IK-�E� �?-<3H3 �<* �/����d79-?��V61�:* ���KA!��C�,3<Q* ]PO���-���0>�/h/#�C(+*X-����+5wsP*.7��+5�c5��V79-:3�(KG�>@* ���-�xI�2>��C* ��.*H/���+5 � � & 795C59-����6#<*x/#�C(+*X3 & �C*)�Hs¢*.7#�+5#5#�V79-43)Q$]J���43��9>@����g6�)*H/?O�� ���<(K-�����x*���,* �����LA!<793,(K* <3�� & 7<�8�d7��&�r6�<*����CA�zB & 7��L/#�C(7�45����C* )O����� �=79-:-:/9YrO�<3HG��� �� & ����#������A�9>�5����<*,79-�� � )OUO�<G���KO������9Q %'& �:3 �430<3,G�����=79-:-:/(�.*H(�8�9>�3���<(K* ��P/B & ���26�<*'� & l(��KO�<*H-:/����+59���N>@*.793)�.*,(����.(K* 4�43=�����X3���)(+* 8Qg]J�'�43�79-:3 �7�.*H(�4�9>L*�<-�=79I��:-��/�P/e7��+O>¥78(+-�����C-<*,7#����8QT]J�8�:3����K-:/c3 �CA�)B & 7���-<3,3��.*,(� �9>^7xO������-� & (KAg7#�%���-��)*H>¥7#��E� & 7�� & �:O�<3L79-4-� & 'B�78*��.3��9>_7�3M/N3)��)AkYbI���d79(K3 ��lAg7#�V/4�<793 )3S/#�C(%�<7#�����#� & �:O� � & 'BL79*��,3�p � & )/:����+O!� �3 & ����2� & * �C(+5 & ���gA?7�����<* & �rB & 79*HOe/��C(F�,*H/9QF���,� & A�#� & <* & 7#�+O_Y��:> � & x3M/b3���)A �:3z*�d79-:-:/B�<-:-`O�<3��45���)O�{@B��/� & 78I+3��,*.7#� �����#�_Y�����d78G+3,(+-47�������_Y ���N>��C*,A?7������� & �4O����+5+Y�3)�.* �#�+5%�P/bG����K5+Y�7��+O��� & )*JG+* ������:G+-�)OnG+* �9G�)*����<3.�2Y?� & ���/��C(hAg7d/kI�l78I+-�A� �jG+* �r6��4O�c7 & (+A?7#� ���-��)*H>¥7#��A� & 7<�A?793HDb3 21��.*,7#����9(+3(�4AcG+-�)A!��C�.7��������O���.7#�4-�QJmE26�<*)� & )-�)3,3<YG���9A?G+-21e3H/b3�� <Ac3=���F� & & 7#�KO+3�8> �������CAcG� ����-�:�9*5���+79O�<\E(;7<��<-0/ �.*.7�����)O G�)*,3�������)-J{ ����<-:(+O���+5e(+3�<*H3<Y6�CG�<*.7<���C*H3<YT3M/N3)��)A78O+A!����43)�.*,7����C*H3<Y'7��+O 3 ��)(+* �/�P/+� ����<*,3.�%��� & <* ��-�.-:/ * )G+* )3 ��-�a>@(+*)� & )*j* �43HDE3<Q { %'& � <5��:33M/b3���)A ���V6��9-:6�)O ��7� & J������������)3u3 & ���#����+5lO��rB��9� & ]P*.7#���47#� � �:*,I+(K3 �:3o7�5��1�bO721K79AcG+-�8>�7lI;79Oe(K3 <*E���-��)*H>¥7#��'� & 7�� ���9(+-4O ���#� �r6�<*����CA�p 7#�KO,���a>¥7#� � [1+7���<*HI;7�� <O�p 3 �CA�(�9>� & -��:A!�/��7�� �����+36�9>G� & �3M/b3���)A ��,3 <-0>ZQ��

* ¡ *�<O £f* ���CDE3 ��3 � £L(��:-4O$�������� � & * �rB ����v7dB�7d/ � �43'���#�U7e5����NOhG+*,7#��� ����!���"5����)*.79-W{�7��+O¡ *�<O & 793lA!�9* a* �����-�,-:/ ���#� <O � & 7<�[��p 79-� & �C(+5 & � & 9��������<G�� & 793c3 �9A!aA�<* �/�.3:�0> ����G�<*H3 ��� & 7936������79->�����-�.* �9->��6#<*fI��#� & � & � & *��rB�sZ7dB�7d/cG+*��#���#�P/bG�W7��+O�� & u* d78-0sJ� & ���K5J3H/b3�� <A�Y7��+O �:> ���:A!v7#�+O�A!�#��)/ 79* &���#�c7��l3��.79D#8Q�0k(�� & I� � � <*:�432��� & 7d6��7eB�<-4-¦sJ� & �C(+5 & �Ms;�C(��26��C-:(�������;79*M/�3��.*,7���)59/�>@* �CA � & eI�)5����������+5+Yo7��+O~I��78I+-�9����5C*���B /#�C(+*vG+*��#�����P/NG� ���-� �B & 7��?/#�C(~* <79-4-0/ BL7#�-��<O ��B� & �+*,3��gG+-=7���9Q � �/� & A��bO+(+-=78* ��P/ ����O��43)�.* �:I+(�� <O 3M/b3���)A?3)YB�<-:-0s¢O� �>��<OF��C� <*M>¥7#��)3<Y?�CG�<*,79I��:-���P/v3���7��+O;79*HO+3<Y`7#�KOn3��,* ���+5ws¢B��4-:-�)OeA?7#�;795�)A!��-�dY � & �:3 �43W76#<*M/aG��rB�<*H>@(K-`79G+G+*��V7#� & Q�3N(�� & 7#� )6#�C-4(�� �����+79*H/v79G+G+*��V7#� & �d7#�9)6#��,�r6#<* ���CA�(� & -=7#��D!�9>>��9* <3��45 & �����%� & ��C*��45���;79->��������)G��dQ � �rB�26�<*)Y�� & W3,(�����<3H3��9>`3,(�� & 7#�%)6��9-4(�� �����;78*H/l3��,*.7�� <59/O�<G���+O+35����79� & �C*��C(+5 & � �����(�$���T(��+O�<*,3)��7#�KO����+5,�9>8� & g3,(K*H6��:6879I��:-��/�P/�* )\b(��4* )A!��-�.3<Y�7��+O78-43 ��O�)G���+O+3!��� � & ���CAcG+* & ��+3��:6#n79O & <* �����9��� � & �93 e*�<\E(��:* <A���-�,3�� & * �C(K5 & �C(���� & O�)6�)-��CGKA!��C�<Q

* ¡ *�<Oc£L* ���CDE3 ��3��;*,3)��)O��� �����:�8> � ��� � � ��� �(� � � � ��� � � � ���JA?7#���-�.7#����)OA� & 7<�6)6�)*H/cG+*��C5C*.78AlsA�<* ���<OK3 � �c(��+O�<*H3��.7#�+O � & (��-���:* J3M/N3)��)AkQS];�9� & 3 ������+O9<O��������"}�� � ��Y�£L* ���CDE3o* ��<7#�-�.3)Y3)��7�� ���+5'� & 7<� & WBL793�Bo* �#�+5l7#�+Oa��79* �;783LB�783'* �45 & �<Q��$78* �;793 �|3 ��������<G��,3x{H} � �bY;� �9�KYK� � �NY+� �9�NY�8�C�NY_�9�C�NY_�9�C�bY �9�C�bY �9�N�9Y �8� �NY��9�V�NY_�9� ����Y_-�43�� <O � & * �����C-��C5#���d78-4-:/v*.7�� & <* � & 7#� �E(+A�<*����d78-4-:/K��8>FO�����CAcG��93 �� ������YSA��bO+(+-=78* � � 7�������_Y�78I+3��,*.7#� �����#�_Y��,*.7#�+3HG;79*�����2/CYo7#�+OB���N>��C*,A?7������� & �:O����K5��+O��<O�79* J6#<*H/aG��rB�)*H>@(+-�Y><3HG�����=78-4-:/!���a3)�.*,(����.(K* ���K5g7#�KO�O�<3 �:5�����+5l-=79*H5�JG+* ��§�����,3<Q

*�� ���NOn3��9>@�PBL79* 4��K5������<*����+5jG+*,7#��� ����UAg7d/e3 �)A ���jI�U6�)*H/�O�� ���<(+-/� ����7#� & ��)6#9Y`I+(��(�/���:3��V6978-4(;79IK-�:���$� & g-����+5�*,(��_Qk]J�5�43X(+3,(;78-4-:/�B��C*)� & � & %2i.�C*)�A�0>L/��9(+*U5��V78-43�79* !�����-�.*��:6��=78- Q¡ �C*!21K79AcG+-�8Yu>��9*,5� �a79I��C(��jA�<*�<-:/B�.*M/����+5 � ��G+* ����KO � & 7��v/#�C( 79* � �9Ib§��� � �C* ���-��)O �IV/�(+3 ��+5�7e>�)B �CIb§�����Ms;�C*�����-� <O �����C-43)Q � �+O�<*,3)��7#�KOB� & jO��)G�)*�I���� ���.34�9>u79I+3)�.*,7#��� �����_Y

) � +

Page 159: Practical Architectures for Survivable Systems and Networks (Phase

����d78G+3,(+-47�������_Y�G��C-:/bA��C*,G & �43HAkY�7��+O ��� & )* �/��7#����7��� � <*,Ac3:�9>�� & �3M/b3���)A 3��,*,(�� �.(+*� � & )/��+O+(���jp 7#�KO 79I��r6�k79-4- & �#���C*4� & 9��������<G1�&�9>W5��1�bO�O�<3��45�� 3��.*H(����,(+* 8Q#{ 31� � & ��21���/��)AkQ �

* %'& J\b(��#��F>@*��CA � �:A � �C* �����+5l7#�KOa£L* �47#�ayz7��+O�<-:-_7���� & JI�<5��������+5A�9>$q & 79G1��<*��A�:3L6����78- Q¡ (+*)� & )*,A��C* 8Y"��5�43A�����4����C(K5 & A!)* )-:/$��� & 7d6�j5����bO�O�<3��45���3)�.*,(����.(K* 9Q ���C(�AU(+3)�c79-43����+3,(K* 8� & 7���3 �:5������>�d7#�-��3)�.*H(����,(+*.79-KI��C(��+O;79*���<3'{�793 ��:�43��C-=7�� ������D#)* ��)-43)YbO��CAg7����x3�<G;78*.7�� �����_Y7��+O(�d79-:-����K5'3 <A?7#�-����<3.��O��E���#�^5���G���9A?G+*��CA��43 )OJIV/=� & 6�4AcG+-<A���-��7�� ������{ �:>���+O��)O�/#�C( & 79O5#�1�bOU3��,*,(�� �.(+*�����5� & ��;*,3)��G+-=7���r�_p 793"���2� & �<793 ��9>�O��CA?7#��X6����C-47�������+3)Y9I+(Ki�<*"�r6#<*K5���Bo3)Y(���� & ���D�<O"G;79*.78A! ��<*H3<Y 7��+O�7g*.7w>@���9>��#� & <*FIK(+5C3 � & 7��J*�<3,(K-����nI+-��B���+5%� & A���-� <5C*���P/9�9>� & xO�<3 �:5��_Q � * � & �������,(+*.79-^3��,*,(�� �.(+*�<3�� & 7����� & )* ��-�,-:/a>¥7#���:-��/��7�� =�����+3)�.*H(���� �:6�xA!�bO+(+-479* �/�P/CYGK* <O������.79I+-E���CA?G��C3��������_Y�26��C-06879I��4-��P/9YN7��+O%��C� <*��CG�)*.79I��4-��/�P/�3 & �C(+-4O?I�E� & <*��43 & <O_YKI���d79(+3�� & )/vG+* �r6��4O�(����C*,A��C(+3'-���+58s ��)*,A I���� ���,3<Q

* 3 & �C*��MsJ� <*,A �9*f-�1�<79-��CG�� �4A�� � 7�������:�43f7XG��CG+(+-479*�-4(+*� � & 7����43f79-:A!�C3)�S79-:BL7d/b3����9(��-��<*HG+* �bO+(��[s� �:6#���2� & f-���+5W*H(��_Q %'& �79-/��)* �;7�� �:6#SO��1)3D���#� & 7d6�����WI���,*H/����K5 � �F7#� & �)6#�5C-��9I;79--�CG�� �4A?7��� & 7��2�4368793��,-:/ �����eO�� ���<(+-/�dQa]J�5�:3U79ON697��C�.795���C(+3xA�<*�<-0/ ���eI�v7dBL79* %�9>o7#�+O �����+3��4O�)*5��I+79-=7#����A� & c-���+58s ��)*,A �:3,3H(�<3�I�2>��C* l-d79G���+5&����3 & �C*��MsJ��)*,A �������)-4(+3������+3)Q %'& ?-���+58s ��)*,AG�<*H3,G��� ���:6#7�9>@���� ���+O����d7<��<3'� & 7<�U/��C(�3 & �C(+-:O�O��F� & ���+5C3x*.79O���d79-:-:/�O��:i�<* ��-�.-:/h>@* �9A B & 7<�� & 3 & �9*��Hs ��)*,A G�<*H3,G��� ���:6#X3H(+5C5�)3��,3<Q

%'& U*�<-47����06�x*��C-�)3 �9>6[1NG�)* ����-���=78-�DC���rBo-�)O+5��7��+O�5����<*.78-$G+*��������4G+-<3z79* A�����+3��4O�)* <O ��,� & ���#�C� 21��E�9>D)O+(��<7������� ��� � G+G���KO��01 � Q

���� � $ �� � ' � '��#$ ��� � � $ � ' � ��!�

q & 79G1��<*H3 ��7#�+O���G+* �r6��4O�c5C(��:O�<-����)3<Y^G+* ������:G+-�)3<Y�7#�+O�79* � & �/������.(K*.79-�3��,*,(�� �.(+*�<3x>��9*XO�)3 �:5������K57#�+O �4AcG+-�)A!��-�����K5�3H/b3�� <Ac3F7#�+O ����PB��C*HDb3zB��� & 3��,* ���K5���-�z3,(+*M61�06879I��4-��P/g* <\E(��:* )A!��C�,3<QoR$1NG�)* �¦s�����E� ��+OK3�� �X3H(+G+G��C*���� & uI�<-��)>�� & 7<� & �45 & -0/UG+*��������4G+-<Oc7#�+Og79* � & �������,(+*.79-:-:/xA!�#� �:687�� <O�O�)3 �45#�+3& 7d6�e7hAx(�� & 5C*�d7�� <*c-��:D#<-� & ���bO �9>=�����V6�<*H5����K5 ����3H/b3�� <Ac3v7#�KO �� �PB��C*HDE3%� & 7<�!�<7#� 3H(�����<3H3Ms>@(+-:-:/?A!���o3��,* ��+5���-�o*�<\E(��4*�<A���-�.3)Y�7#�+O7� & 7����d7#� 26��C-06�5C*.7���)>@(K-4-:/����c7#�����CAcA��NO;7<�� � & 7#�+5���+5* )\E(��4*�<A���-�.3)Q ];��G;79*�� ���)(+-=79*)Y & �:5 & -:/h3)�.*,(����.(K* <O�O�)3 �45#�+3<YSO��CA?7#����3 <G+79*.7�� ������Y"����<79G+3,(K-=7�� �����_Y���N>��C*,A?7������� & �:O����+5KY �<-�<7#�+-0/�O� ����<O ��-��<*M>¥7#��)3<Y^>��C*,A?79-�A��NO�)-43=�9>����CAcG��C3 �/�����#�"7��+O ��-��<*������bs��������06���P/CYW7#�+O A?7#�V/ �#� & <*7���#����)G��.3921NG+-�C* )O �� � & �:3j* <G��C*)� �d7#� 79-:- & 7d6��6�)*H/ 3��45������>�d7��C�G;7d/��8i�3)Q

��

� � � � ' � � � � ' � � � ' � � �%'& �:3W* )G��9*����:3E�#�+-:/aG;78*����8> � & XG���� �.(+*�XB��/� & *�<3,G��� �����cB & 7�� �43u(+-� �4A?7���)-:/&���<O�<O_QJy�<\E(��:* [sA���-�.3x79* ��9>'-�� �,-�U(K3 &�0>�� & )/"79* ����#�221NG+-������.-0/ & �����C* )O ����79* � & �������,(+* )3<Y �:A?G+-<A���-��7<�����#�_Y)6#�C-4(1�����#�_YT7#�KO �CG�<*.7<�����#�_Q�����%�:A?G��C*��.7#�-��3 ��5�9>u7#� ���:6��/����)3* <-47�����+5 ��� � & %)3��.79I+-��:3 & A���-�2�9>7a3 �C(��KO�I;793��43J>��C*3,(K*H6��:6879I+-l3H/b3�� <Ac3U7#�+O$�� �PB��C*HDE35���V6#�C-:6#<3'21NG�)* �:A!��C�.7��������B��� & � <3��,I�)O+3� & 7��=�d7��hO�<A����+3��,*.7�� 5� & U>�d793��4I��:-���P/ �8>�� & l79*�� & �� ����,(+* )37#�+O ���#����)G��.3JO�)3 �)* �4I�<O$��� � & �:3F* [sG��C*��<Q�3N(�� & 7#� )i��C*�� �:3o79-4*�d79ON/g(��KO�<*'BL7r/gB��� & ���&� & � *,AX/jy�<3 <79* � & �`79I��9*.7�� �C*H/&3N(+*M61�06879I+-�

) � )

Page 160: Practical Architectures for Survivable Systems and Networks (Phase

3b/b3�� <Ac3J7#�+OnmE��PB��C*HDb3��`79I��C*,7����C*M/"{ 3�3Nm �^�2Y¤(��+O�)*E� & UO��4*��� �����#�,�9> � �-� & ���V/n£�79* ��<3F7<� ¡ �C*��0 ���KA!�C(1� & Q � A����+5 �#� & <* � & ��+5C3)Y�3�3Nm �&�43H��E6#<3)���45C7�����+5u7#�+O5[1NG�)* �4A���-� ���+5oB��� & >�<7��.(+*�<3H� & 7<��d7��!�� & 7#����W3M/N3)��)A�7��+O!����PB��C*,D�3H(+*H6��:6879I��4-��/�P/CYC*�<-47�����+5����'�CG�<*.7<�����K5�3M/b3���)A?3)Y1����PB��C*,DlG+*��#���8s���9-43�7��+O&�� �PB��C*HDC���+5�3��9>@�PB�78* 9YK]Z��3���<(K* ��P/9Y & 79*HOKBL79* 8Y+* �C(1��<*H3'7#�+Og3 <*M6�)*,3<Y�7��+O7��V6��4*����+A���-��79-���#�+3 �:O�<*,7�������+3<QE3NG�������>�XO��4*��� �����#�+3E����<-:(+O�=��7�������d79-H�� �PB��9*,DE3<Y_3��4AU(K-=7�� <O ��7#� �����<79- ��)3�����+5+Y�6��4*Ms�.(+79-TG+*��:687���5����PB��C*,DE3)Y$7#�KO�* �CI+(K3����0>�/����+57�CG�<*,7�����+5v3M/N3)��)A?3)Q �H��E(N1�7#�KO�* <-47���)O�3H/b3�� <Ac3X7��+O�� �PB��C*HDl79* � & �������,(+* )3L79*� & �45 & -:/X* <-)687#�-�dYE(+3����+5'�����KG+* �CGK* �� ��79*M/UG+*��#�������9-43�7#�+O��CG���Ns¢I��d1U3 �9>@�MsBL79* JB & )* )6#<*zG��C3H3 �:I+-�8Y�7#�+O �<*�d7�� ���+5l3 �9A!(��2B ���K>@*,793��,*,(�� �.(+*�<3u793'B�<-4-�Q��0�C*)��79IK-�=���9A?G+(1�����K57#�+OkA!�9I��4-=���bO�U79*�XI��#� & �9>"����C*HA!�C(K3z*�<-�2687#����(���gt��Vt 7��+OnG;79*)����<(+-479*,-0/%� & � *,Ax/9Q 3�3Km �G+-47#�+3D�#��G;79*�� ��<*����+5zB��� & m�3 � Y-3KR�]�YCtF])3 � Y � *,Ax/Uq�RSq'� 0"YV7#�+O:��� & )*D�C*H5V7#��� � 7�� �����+3)YC793�O�<3��4*Zs79I+-9Q %'& 23�3Nm � 2i.�C*)�u7#�+O �#� & <*o7#� ���061�/���<38�9>G� & �438�P/bG��79*�J(+*,5#��-�.-0/&���<O�)O_Y�7#�+O�3,(+G+G��C*)�����K5� & <A �:3 & �45 & -:/v*�����CA?A���KO�<O_Q

��� � � � � � ������ ����! � $ � � � ��� ' � � � � ! � � � ��� �

t�<3HG��� &� & jI�<3)�����-����C� �����K3A��� � & jG+79*��4�9> � & a79* � & �/������.3:�8>W3M/N3)��)A?3c7#�+O �� �PB��9*,DE3 & 7r6���+53��,* ���K5v3,(+*M6��:6879I��:-���P/a*�<\E(��:* <A���-�,3<Y_A?7#�V/a6N(K-���)*.79I��:-��/����)3u79* X3����:-4-`-��:D#)-:/7���g* <A?7#��_Q �z79*,ONB�79*��43c79-0B�7d/b3?7hG��#����-���=78-'3 �C(+*��� �9>F3M/N3)��)A >¥7#�:-4(+*�<3�{¥7#�+O_YfG��#� ��-���479-4-0/CY�G & /b3 ��d79-z7�� �.7#��DE3��[Y8��/� & )*�.*,7#�+3�����-� �C*o(��+3H(+*,A��C(��-�.79I+-�B��� & �C(��uG & /b3 ��d79-`*�<G;7#�:*<Q %'& �3 �9>@�PBL79* 2�4AcG+-�)A!��-��7�� �����vGK* ����<3H3�43>@(��+O+79A!��-��79-:-:/n>@(+-:-6�9>'* �:3,DE3<Qk�FG�<*.7<�����#�;79-4-0/CY`DC���rBo-�)O+5�d78I+-�c3H/b3�� <A 7#�+O ����PB��C*,D"79O+A������:3Ms�.*,7����9*,3�78* �� & *�������d79-:-:/4���g3 & �C*)�'3,(KG+G+-:/9Y;7#�+O!� & ��4*�*��C-� ���vA?7#��C�.7#�������+5X7x3��.79I+- ��V6��4*����+A���-� �:379I+3��C-4(1��<-0/9�<* �/����d79-�Qu];�n79O+O��/�����#�_Y��9G+G��9*��.(����� ��<3z79*�x*.78A?G;7��C�z>��C*WA?79-������C(+3 % * �w§,7�� & �C*H3 <37��+O§H(+3)�UG+-47#��� 5�79DV/h3 �8>@�PB�79*�lp <3HG�����=78-4-:/F����A��CI��:-�:���NO�?7#�+O�(��-�.*,(K3���)O�3 )*H6�)*,3)Qe�G��� �.*.7<�����#�+3>@* �9A �C(��,3 �:O��B��4-:-+79-0B�7d/b3�I�'G��C3,3��4I+-8���l3��CA!�>��9*,A �9*�7#���#� & <*)Yb7#�+OlA!�:3,(+3�'IV/:���+3��4O�)*,3�*�<A?7#���+37#� ����C*,A��C(+3J3��C(+* ��4�9>L*��43HDb3=���Ag7#�V/ �P/NG�<3(�9>f3H/b3)��<Ac3<Q ¡ (+*)� & )*,A��C* 8Y I���d79(K3 l3H/b3�� <Ac3x7��+O�� �PB��C*HDE3E����+O,���#�����cI��G���CG+-(� �C-�)*.7#�-�<Y+(+3 )*,3W79* (����)6���.79I+-:/v7c3��C(+*���'�9>T*��43,DE3�p ���?A?7�����<*& �rB O�2>���+3��:6�)-:/$� & c(+3�<*A��C� <*M>¥7#��)3XA?7d/�78G+G�<79*(���eI�9Q %'& )3 &[1NG������)O�* )3 �4OK(;79-S3 & �C*)�����CAls���K5C3LAU(K3��'I�F7#�-� �����:G;7�� <O_Q�y�d78-0sJ� �4A�u7#�;79-0/N3��43S>��C*fA��43H(+3 F7#�+Oj7#���CAg78-:/lO� ���� ������j3�� �4-4-�*�<A?7#���+3O�)3 �4*,79I+-793u7l-4793��o*�<3��C*��<Y>)6���,�� � & I�)3�� �9>�3H/b3�� <Ac3<Q

���� � ����� � � � ��� � ' % ' � '�� � � � ��� � � � �� � � � ! � � ' ��� !�

%'& * ����CAcA���+O;7<�����#�+38�9>D31�����������KQ ��GK* �r6��4O�7:���#�+3 �:O�<*,79I+-�J3 & 79*HG�������+5:�8>$3��CA!J5#���)* ���J*���[s�CAcA!��+O;7�� �����K3��9>6� & l*�<G��C*��(�9>�� & ?��*�<3 �:O���-� �|3xq��CAcA!�:3,3 ����F���"qL*������d79-�];�K>@*.783��.*H(����,(+* c��* �ws������ ������} �r� � � Q�]J�"�43 ��-��<*�<3)�����K5����������-�.*.783���B & 7�� ���CA�<3 �9(��"�9> � & �3,(+*M6��:6879I��:-���P/Vs¢O+* �06���2��������<G1�.3�9>G� & �:3'* )G��C*)�oB��� & � & J>@(��+O���+5c79* <793o3,(+5C5#<3�� <OkIE/%� & Xq��CAcA!�:3,3������_��CQT];�N>��C*,A?7�������j793H3,(+*,7#�����NQT];�-�,*,(+3������aA������� �C* ��+5�7#�KOkO� ������������KQ$��(K-���)*.79I��:-��/�P/g783,3 )3,3HA!��C�W7#�+O�3H/b3)��<Ac3z7#�;79-0/N3��43� Q�y��43HDCsPA?7#�;795�)A!��-�'O�����43������a3,(KG+G��9*��

) �

Page 161: Practical Architectures for Survivable Systems and Networks (Phase

�NQ���*��#������������7#�+OaA�����:5V7�� ������KQT];�����4O���-�u* <3HG��#�+3 X7#�+O�* ����r6�)*H/%'& l* ����CAcA���+O;7<�����#�+3��9>��C(+*J* )G��9*���79O+OK* <3H3XA?7#�V/�*�<3 <79* � & 7#�+O�O�26�<-�CG+A���-�x793,G��� �.3(�9>

�� <Ac3U�CY^�NY`�NY`7#�+O �NY_B & �:-��7�� � & l3.78A!5� �4A�x>����<(+3����+5jA��C* �IK* �V79OK-:/ ����3,(+*M61�06879I��4-��P/�*.7<� & )*� & 7#��§H(K3��?3 ��)(+* �/�P/CQ ]J��<A � �43c79-:3 � �4AcG��C*��.7#�-�dYS79-� & �C(+5 & 3��CA!2B & 7��cG�<* �:G & )*.79-8� �$� & �>����<(K3�9>��C(+* )i��C*��,3<QU£���d78(+3 4��WO���<3=���#�(�)* <7���l7#��78* � & �/���� �.(+*,79-$>��C*�����+5g>@(���� �������{ �#� & <*�� & 7#� � & A��#� & )* & ���bO2�:O�d7�� & 7���B�f3 & �9(+-4OU*�<O+(����� & ��E(+AUI�<*0�9>+6b(+-��<*,79I��4-�� ��<3?� & 7���AU(+3)�TI�L* )G��9*���)O��2YB�F3 �:A?G+-0/c793,3H(+A� � & 7<�8<A�<*H5�����)/?* <3HG��#�+3 �� d79Ac3fB��:-4->211�:3�� ��v7xA��C* E)i��� ���:6#W>��C*HA � & 7#�j7<�G+*�<3 ��-�dQ

]J��)A � �d78(+3 )3u(K3u3��CA�=��������<*��_Q � -� & �C(+5 & * �43HD � �#� � � ��� �����43����7<3H3 ������B & 7�� � & �43'* )G��9*�� �:379-:-�78I��C(1�dY¤7#�+O�3��.7�����X*��43HDk783,3 )3,3HA!��C�(�:3 �:A?G��C*��.7#�-�x{¥3 �431��������� �NQ0�r�V�[Y�� & A���������#�,�9>�O�����:3 ����3,(KG+G��9*��'�����C-43(�43�G��#����C� �=79-:-:/eO;7#�+5�)* �C(K3<Q10e7#�V/$�9>�� & �C3�!�����C-:3(� & 7��XG+(+*HG��C*)�2� � ��� � � �F* �43HDE37#� �.(;79-:-:/5������C(+*.785�z(K3�� �2�:5����C*� ��<*)��7#��?*��43,DE3�*.7<� & )*�� & 7#�cG+* 26���-�8� & <A�Q�� ��B�)6#<*)Y1� & �C3 ������C-4379*�:�9>@����hI+793 )O$�#�$������9*,* �����793H3,(+AcG�� �����+3)Y`7#�+O�>@* )\E(���-�.-0/ �45#���C* 2� & :��C� <*,7#��� �����+3 �C*FO�)G���NsO�������<3u79A����+5lO��:i�<*���-�o* )\E(��4*�<A���-�.3)Y����CAcG�������-�.3)Y�7#�+O � & *�d7��'>¥7#� ���C*H3<QSy�<-��47#���������3,(+G+G��C*)������C-:3 ���jG�<*M>��C*,A * �43HDeA?7#�;795#<A���-�=�43F6#<*M/�O;7#�+5#<* �9(+3(���F� & l79I+3 �������9>SO��<Gh(��+O�)*,3��.7#�+O���+5�9>6� & �* �43HDE3<Y?� & ��4* �d79(+3�<3)Y�7��+O � & ��4*������+3 )\E(������<3)Qc�=� � & :�#� & <* & 7��+O_Y �:>�B� & 79O � & 7��JO��<G(��+O�<*,3)��7#�KO����+5KY�B�jA��45 & � & 7r6#jI� � � <*�3H/b3)��<Ac3<Yf7#�+O � & j* �:3,DE3:���9(+-4O�7����.(+79-4-0/"I�a7d6����:O�<O � �7aAU(�� & 59* d7<��<*'21�� ��-��p *.7<� & )*'� & 7#� & 7d61��+5 � �kI�cAg7#�+795�<O � m )6�)*�� & <-<3,3)Y�7#�$���-��)* <3)����+5G��#����C� �=79-�7�� � <AcG�� ����\E(;7��C� �:>�/j*��43HDb3o7��+O7���lI;79-47#����WO�)>���+O����K5g795C7#���+3)��G�<*�����06�)O � & * d7<�.3�B��� &B & 7����d7#�nI�A�����+3 �:O�<*�<O�7#����)G���79IK-�x*��43HDb3 �43W5#�:6���nIV/ 3N79-� <* �79-�Q$}��C�C��� Q %'& 431�9>@�PBL79*��R"�+5��0s���<* ��+5l];�+3�� ��,(����7��zq�79*���<5#��2s*0 <-:-���� � ���:6#<*H3 ��P/ �:3�B��9*,DC���+54���k7A��7w11�����CAx/7�9>�* �:3,DE3{ & ���.G_� �C�wB'B'BQ�3 �� Q �<AU(_Q <OK(��2Q� 5����<*,79-�O��43 �)(+3,3������ �9>H� & F* �:3,DE3 �9>^* �:3,D?7#�;79-0/b3 �43���,3 <-0>H�d7#�aI�W>��C(��KO7���a7UI+*���)>`IK(����������43��:6�

���#�C�,* �:I+(������� �9>u£��CI�q & 79*������h{,}�� �9��� Y�3����� ����� �NQ:�d�KY�G;795�)3l� � �rsM� � �9�2Q ¡ �9*521K79AcG+-9Y �r6�)* )3����¦sA?7�����+55� & J* �43HDE3 �d7#�9�d79(K3 J(��������)3,3,79*H/9)i��C*)� �+(��KO�<*�<3�� �4A?7�����+5A� & J* �43HDE3 �d7#� �d78(+3 O��:3.793)��<*H37#�+O�* <3H(+-�A����*�d7#� ���06�vG;7������!��� � & vG;79*)�A�9>oA?7#�;795#<A���-��7#�KO�78i����� <O�G���CGK-� �6)3����:Ag7<��<32�9>G;79*,79A����)*,3�78* a79-0B�7d/b3�3,(+3HG����� ��G�)* & 78G+3lA!�C3)�:�4AcG��C*��.7#�-�dY0� & <*�7�43U3�<-:O��CA 7��E/�* <79-�\E(;79-��P/���#�C�,* �C- �#� � & * �:3,Dj793H3 )3,3,A���-� ��.3�<-0>ZQ

��� � � '��#$ � � ��$ �

�F(+*�� & * ��/#d79*H32�9>�)i��C*)�(��� � & �:3JG+* �w§������* )G+* )3 ��C�2���+-0/�7jI�<5���������K57�9>�B & 7��'�43J-�4D#)-:/9���aI�7e-���+5e\E(�)3��<Q %'& <*�a79* ?Ag7��E/h3 & �C*��MsJ� <*,A A�d793H(+* )35� & 7��A�<7#� I�%��79D��� � & 7��xB��C(+-:O 5C*�d7��,-:/�4AcG+*���6# � & F78I��4-��P/A�8> 3H/b3�� <Ac3'7#�+O!����PB��C*HDb38� �x3,7����:3H>�/4�<*��� ���d78-;* <\E(��:* )A!��C�,3<Q��E�rB�)6#<*<YKAg7#�V/-��#�+58sJ� <*HA �:3,3,(�<3u* <A?7#��&���lI��79OKO+* )3,3 )O_Q* � A���<O ���7[1NG;7#�+O�>@(+*�� & <* ���F� & l78* � & �/���� �.(+*,79-$O��4* ���� �����+3F793WB�<-4-T793 � & �* <3�d79*�� & 7��+OO�)6�)-��CGKA!��C�*�����CA?A���KO;7�������+3E�C(��.-����)O ���F� & �43F*�<G��C*��<Y_-�<79O���+5%���a7j-)6�)- �9>SO� ��7#�:-$3,(N>=s��������-� ���7��;79I+-x3HG���������U5C(��:O;7#����5���v3M/b3���)A O�26�<-�CG�<*,3zB��� & * <3HG�����=� �%� & xA!�:3,3 ��+5%�9*O� �>������-�����9A?G�������C�,3<YE7#�KO�� ��3��4AcG+-��0>�/(�����K3 �4O�<*.78I+-:/2� & �� & 79-:-���+5�<3"�8>.�:A?G+-<A���-����+5+Y<�����bs�+5C(+* ��+5+YN7#�+O7�CG�<*,7�����+5U3M/N3)��)A?3o7#�KO7����PB��C*,DE3 � & 7�� �d7��jI�F3��45������>�<7#�-�.-:/cA��C* z3,(+*M6��:6879I+-� & 7#�jB & 7�� �:3'G��C3H3 �:I+-��� �NO;7d/9Q

) � *

Page 162: Practical Architectures for Survivable Systems and Networks (Phase

* � WAx(+3��LG+(+*,3H(�W6��45#�C* �C(K3,-:/l3��CA� �9>?� & WA��C3)��G+*��CA!�:3 ��+5�79-� <* �+7����06�<3S>��C*6� & F*��CI+(+3)�����>�d7ws� �����7�8>D�CG���bsPI��r1j3 �9>@�PBL79* 8Y�7#�+O <3)��79I+-�43 & 3HG�������>�X3)�.*,7���)5���)3�>��C* �4AcG+-�)A!��-�����K55� & )AkQ

* � �AU(+3)�kIK(��4-:O GK* �#� �#�P/bG��3H/b3)��<Ac3n7��+O (K3 � & )A ��� ��)3��.I�<O ��V6��4*����+A���-�.3k7#�4A�<O 7<�[1NG+-��C*����+5A� & * )-�)687#�-�uG+*,7#��� ���d78-?�43H3,(�)3<Q

* %'& X*�����9A?A���+O+7�������+3��9>D� & �43o*�<G��C*��uAU(+3)�WI�(��79D���e3�<*����C(+3H-:/jB��/� & * <3HG�����E�����4AcG+* �r6�)O)O+(��<7��������7��+O 7dBL79* ���<3H3<Y"��+79I+-���+57� & ����#����)G��.3 & <* ����$����I�4��79(K5 & �5���7#�<79O�)A!��?7��+O��+O+(+3)�.*��=79-^Ag7����+3)�.* <79Ac3F793FB�<-:-T793FB��/� & ��F���+3)�.*H(���� �����;78-$G+*��C5C*.78A?3E�9>6� & lt�)G;79*��,A!��-�=�9>t�2>���+3��7#�+O � & � *HAx/CQ

��� � ��!��� � � � � � ! '��

� & 7d6�:�C(1�.-����<OeAg7#�V/�* )3 <79* � & 7#�+O�O�)6�)-��CGKA!��C�(��������<G��,3�� & 7��F79* & �45 & -:/�* )-�)687#�-�E���&� & 3,G�������>�<7�������_YVO�)3 �:5��_YVO�26�<-�CG+A���-�dYb7#�KO��9G�)*.7�� �����:�9> & �:5 & -:/�3H(+*H6��:6879IK-�'3H/b3)��<Ac3f7#�+O4����PB��C*HDb3)Q%'& �78* � & �/���� �.(+*,79-uO��4*����� �����K3?G+(K*,3,(�<O & )* F��C� <5C*,7��� � & �C3 ��������<G��,3h{ ����<-:(+O����K5"5����<*,79-�� � )OO�)G���+O�������7#�+O�5����<*,79-�� � )O ���CAcG��C3 �/�����#���J7#�+O�G+*���6��:O�j7e3)�.* �#�+5�I;793��43x>��C*X3H/b3�� <Ac3A� & 7<��7#�[s���9A?A��NO+7���XA!�CI��4-�'���bO�8Y_G��9*���78I+-�U(K3 <*JGK-=7��H>��C*,Ac3W7��+O�* �CI+(K3��(211��<(�� ������G+-47��,>��C*HA?3)Y¤A������4A?79-�<*��� ���d78-SO�<G���+O������ ����(��-�.*,(K3��PB��C*�� & / ���CAcG��#����-�.3)Y�7#�+O �CG�<*,7�������;79-6��E6��:* ���+A���-�,35� & 7<��79*�& �:5 & -:/�*�����#���;5C(+*,79I+-�7#�+O 79O;78G����06�9Q �E�rB�)6#<*<YE� & �G+*��CI+-<Ac3vO��43��<(+3H3 )O & )* ���� ���<O ����I����#�K>@* ���-� <O�AU(+-� �4O��:A!��+3 ����;79-:-:/9YVI��#� & ���� & ���C-��95����<79-4-0/g7��+O �����-���� & ���C-��95����<79-4-0/CQ

0k(�� & B��C*,D * )Ag7#��+3!� ��I�eO�����F� � O�<A����+3)�.*,7���F� & nG+*,7#��� ���d78-F79G+GK-����<79I��:-���P/ �9>(� & �:3j79GNsG+*��V7#� & YNI+(��SB�FI�<-��26��� & 7��fB� & 7d6�FIK* �CD���j3 �9A! ��)B 59* �C(��KO_QS������W795V7#��_YVB�����#���� & 7<��� & 79*�� & �� ����,(+* c7#�KO �:A?G+-<A���-��7<�����#�F�����K3 �4O�<*.7<�����#�+379* �6���.79- Y�I+(��(� & 7<�2�9G�)*.7�� �����;78-T793HG�����.3X79*�79-:3 �+Y¤793zB�<-:-$783 �4AcG+*���6���+5!)O+(��<7��������7#�+On7rBL79*����)3,3<Q %'& x3��.7���5�9> � & �79*�� & 793E���#� �4AcG+* �r6�)O79G+GK* ����=79IK-:/CYE7��+O!� & o* �43HDE3 & 7d6#W7#� �.(;78-4-:/XB��9*,3 ���<Og* <-47����06�8� �'� & � & * <7��.3)YV6N(K-���)*.79I��:-��/����)3<YV7��+O�����<* <793 )OaO�<G���+O������'�#�"5;79DV/%���� & ���C-�C5��<3<Q %'& (K3<Y�� & JI;793 ��FG+*��CI+-�)A?3SB�J>¥7#��J79*�FI�����CA����K5)6#<*uA!�9* =�4AcG��C*��.7#�-�dQ

%'& �:3A�43A���#�l7,�<793 �9> � (+3)� � O+O�0 �#��)/ 7#�+OB3�� �4*<Qh�G<*H68793��:6#j(��+O�)*,3��.7#�+O���+5 �43A���<O�<O �9>� & ?O�)G�� & 35�9>�� & cG+* �9I+-�)A?3�7#�+O � & ?(+*H5���-�2���)O+3X>��9*�3��C-4(1�����#�+3<Q � -� & �C(+5 & 3��CA�?3��45������>�d7��C�G+*��C5C* )3,3��d7��kI�Ag79O�=���7� & 3 & �C*���� <*,A�Y����CA?A���,A!��-�����c-��#�+58sJ� <*HA 79ON697�����)3E�:3 <3,3���-���479- Q

� -/� & �9(+5 & �C(+* � y � G+* ��§����� & 793'���rB ��+O�<O_YT] & �CG��� & 7��2)i��C*��,32�<7#��I�%�����-�����E(�)O �� � & 3,G��4* �/� �C(��.-����)O & <* 2���eA?7#�V/ �9> � & X>@*����-�.3o>��C*oB & ��� & 3H(+*H6��06978I��4-��P/vA?7�����<*H3zA��C3)� 9v>��C*E[1K79AlsG+-9YK3H(+G+G��C*�� ���+5X5��r6�)* �+A���-��78-?�CG�<*.7<�����#�+3<Y��<*������d79- ��K>@*.793)�.*H(����,(+* )3<Y+7��+OjO��45#���78->���CAcA!)* ��9Y+7��+O�� & 7#�������+5 & (+Ag7��aB�<-:-0s¢I�����+5+Q

%'& vB��C*,OK3:�9> � -4I�<*)�lR"���+3)�������795V7���� 3��<A G��� & /CY"� & �:35���:A!!��� ���4*��<(+Ac3 �)* �4I����+5,� & j*.7<� & )*A��NO�)3��0���-����-�D�9>1� & f79(�� & �C*G�9>�� & �43^* )G��9*��_p O�<3,G����6� & �����C*,A���P/��9>�� & f(��KO�<*H-:/����+5 � & 79-:-���+5�9�

� � � � ��� � � � � ��� � ���'�,�� � � �����$� � � ��� �$��� � � � � � � � � � � � ���� � � � � � ������� � � � ��� ��� � � �� � ��� � �$���(� � � �$�, ������� � � � � � � � ��� � ��� �$��� � � ��� � ���:��������� � � � ��� � � �(� � � � ��� �� � �(��� � � ��� � ����� ����� ��������� � ��� � � � � �7� � � ��������� � � � ���6�������(� � ���� � � �(��� ��� � � �� � ����������� � � � ����� ��� � � ��� � � � � ��� � ���������� -4I�<*)�jR"���+3)������_Y � � � � � � � � �*��� � � ���� %'& �� & �4-�C3 �CG & ���<79- �H�:I+*.78*H/CYo];���8Q:YWmE2B���9*,D�Y;m �UY �r� �9�NY+G_QS� �NQ

) � �

Page 163: Practical Architectures for Survivable Systems and Networks (Phase

%'& 7��J6#<*M/ & (KAUI+-�l3)��7�� <A���-��3,(������������.-0/ 21NG+*�<3H3 <3XAx/�3���-���:A!��C�,3�79I��9(��=� & 426��C-:(������� �9>� & �43'* )G��9*�� �r6�<* � & G;793���� & * �/#d79*H3<Q

) � �

Page 164: Practical Architectures for Survivable Systems and Networks (Phase

� � � � ��� ��! � � � !���� �

]z79A )3,G�����479-4-0/e59*.7�� )>@(+-D� ���$79(+- ��79-� � 78Dk>��C* & �43F6879-4(+79I+-�U793,3��43��.7#����l7#�+Oh3��.*����+5 ������C(+*,795�[sA���-�dYS7#�+O ��� % ���V/�£�78* ��)3l>��9* & �43�O��<GB���-� <* )3������ � & jG+*��w§��� �g7��+O & �43�-���+58s ��<*HA ��-��<*,7#�2s������+3v}|�9�w� Q % ���V/ 78-4A��C3��X3 ��+5C-�[s & 7��+O�<OK-:/h3�� �4AU(+-47���)O 7dBL79* ���<3H3��8>����K>��C*HAg7<�����#�"3H(+*H6��:6879I��4-��/�P/�43H3,(�)3JB��� & ���F� & � *,AX/�7#�+O � & lt��Vt ���F� & lA!�:ONs��r�9�C�93<Y¤7#�+Oh��79(+-TB���-�'����>@* �CA � & )* UB��� &21��,*.7#�C*HO����+79*H/4���<*H59/v7��+O%��C� & (+3 �4793,A�Q � & ��a��79(+-�* ���4*�<O?3 & �C*)�.-0/lI�2>��C* zG+* �w§���������CAcG+-� ������_Y% ���V/a* 2sJ<A�<*H5�<O�793��C(+* � �!���=79- � �r6�)* �+A���-�E�����-�.7#���<Q]�79A 5C*�d7��,-:/4��+O�<I1��<O!���UAx/!3Nyu]"���C-4-d795C(�<3 � ���;7�� & 7#� ��Q.0 �4-:-���g7#�KOj� & �4-:-��4G � QK�G�C*,*,793f>��9*A?7#�V/g3)���4Ax(+-=7�� ���+5XO��43��<(+3H3 ����+3 �r6�)*8� & F/#d79*H3<Q � ���jA?79O�F3��CA! ���#��78I+-�F*�<3�d79*�� & �����-�.* �:I+(�� �����+3���F� & �G+* ��§�����<Qv{ 31� � G+G���+O��¦1�£WQ �W� & �:- ��3 ���� & �����<79-T7��+O�-�d78O�<*H3 & �:G�* �C-<3 ��F� & lR:0eR�y � �`t)i��C*)� & 7d6��I���� �,*,(+-0/vA?79*H6#<-�C(+3o7#�+Oa6�)*H/aG+*��NOK(���� �:6�8Q3K79A��63K7d/bOw§,79*���§�������)O�(+3x7<�23Kyu] ��� � & l-4793��(� & * �cA����-� & 3(�9>�� & cG+*��w§��� �dY�7#�+Oh5����)* �C(K3,-:/

���#�C�,* �:I+(���)O 3 �CA� �������43��:6�,���CAcA!��-�.37��� � & ��>�;79-FOK*.78>@�,37�9>2� & �43g* <G��C*)�dQ�] & 79O ���-� <*.7�����)OB��� &�& �4A �r6�)*A� & v/#d79*H3�O+(+* ��+5 & �:3UG+* 26����C(+3:����d78* �;7�� �����K3U7��lm 3 � 7#�KO t � yu� � YT7#�KO & 7r6#79-0B�7d/b3�5C* <7��.-0/l79G+G+*�����=7�� <O & �436��+3 �:5 & �.3<Q�{ 3K78A!�;3HG�<79* & <79O�)Ovt � yu� � ��3�3,(+*M6��:6879I��:-���P/XG+*��C5C*.78AkY�����<-4(KO����+5�A?7#�V/vGK* �w§�����.3u* )-=7�� <O7���c7#���CAg78-:/CYNA!�:3,(+3�9Y�7#�KO ��C�,*,(+3������jO�������� �����_Q �

tF* 2B�t�d7��eB�783F7c6879-:(;79I+-X*�<3��C(+* ��xO+(K* ���K5!� & ��;*H3��FG & 793 5�9> � & xG+*��w§��� �dY¤B & �� & X3,G���-��PB��v3,(+AcA�<*,3E���nq 3 ��7#�+OeD�<G������ � �C(�� & B & �4-�B��C*,DC���K5&��� & �43z��*��������� ����� & t � & <3 �:3�}�� ����Qx{¥]BL793E�#� & �43 ���9A?A�������8Q��

]f79A ������79-:-:/cO�<-�45 & � <OjB��� & � �,>@*���)O�q & ����K5 �|3 �u/bG�<*H-=7�� 21& � �,G_���9�wB'B'BQ �)3<Q�(+(_Q �+-�� �#�,>@*���)O�� �u/bG�<*H-=7�� 21+�2Y;B & �� & ��+79I+-�)O9� & ��� % R ��>��C*HA �9>G� & �:3uO��1�)(+A!��-�����I��* �9I+(+3��,-:/ �.*.7��+3H>��C*HA!)O 79(�� �CAg785����<79-4-0/ ���-��� �/�.3j78-4A��C3��gG�)*H>��� � & �.Ac-�<\E(��06978-���-�<Q�{ %'& � � % R �F3 �9(+* ��fBL793T79-:3 �u(+3 )O5���z5����<*.7<��6� & uQ|ON61� �;-S>@*��CA B & �� & � & f�0�93�� 3��<* �:G��$7#�+OxG�OK>+6#<*H3 ���#�+3�9>�� & u* )G��C*)�fB�<*�W5����<*,7���)O_YN7�� �.7#������+5=� & *��uA!�9I��4-�>��C*,A?7��.3T>@*��CA ����u3 �9(+* ��9Q �l�G�� <* 09�C3,3�<3& 793fAx/lG�<*,G���,(;79->� & 7#�+DE3f>��C*SG;7�� ����C�,-:/�3 & <G & <*HO����+5xA!�� & *��C(+5 & Ax/4��������479-+(+3� �9> �u/bG�<*,-47���[1¤Q

�u/bG�<*H-=7�� 21��43�§H(+3)���#��uB����+O�<*H>@(K-.21K79AcG+- �8> ¡ * ��31�8>@�PB�79*�E� & 7����43����CGV/b-�2>@�L(��+O�<*�� & ¡ * �31�9>@�PBL79*� ¡ �C(��+O+7����������3 � ���)*.79-���(+I+-��� � ������+3 j{ � � �^�[Q��W>"���C(+*H3 9Y¤]o79A 79-:3 �gGK-�d783 <O9��� & 7r6#(+3�<O�y �� & 79*HO 3���78-4-4A?7#����3 � m � R�Ag7��<3�7#�KO �H)3 �`79A?G��C*)� ��3 � � % R � ��� � & vG+*��NOK(���� ����� �8> � & �:3O����<(+A���-�<Y�793'B�)-4- 793 � ���E(N1¤Y�79-:-?�9>^B & ��� & 79*�=�C(��.3)��7#�KO����+54[1+78A?G+-<3��9>0�CG���Ns¢I��d1a3��9>@�PB�78* 9Q

]79G+GK* ����=7�� %� & &�����K3 �4O�<*.78I+-�c>��<OKI;7#��D � & 7���] & 7d6#v* �����06�)O�>@*��CA A!)AUI�)*,32�9> � & ¡ *��[s31�9>@�PBL79*�?7��+O"�JG���bs)31�C(K* ��lA��r6�<A���-�,3X*�<5V79*HO����K5 & �rB ���a5C*�d7��,-:/,�����)* d783 A� & c*��CI+(+3)����)3,3'�9>�CG���Ns¢I��d1 3��9>@�PBL79* 8Y=�����)-4(+O���+5 � & ��4*7�����-�.*��4I+(�� �����K3&��� � & ���N>��C*,A?79-W*��CI+(+3)�9�CG���NsPI��d1 2s¢Ag7��4-O��:3��.*��4I+(1�����#�j-��43)� ���#� <O9��� 31��������� �NQ0�r�KQ �NQ

�0 ��)* � Q;m <(+A?7#���_Y�09��+-�g��79*,D�Y�q�79-�:>��C*����=7KY � (���X�9�9�C�

) � �

Page 165: Practical Architectures for Survivable Systems and Networks (Phase

� � � ! � � � � � � � � �����V��� ��� �� �� ��� � ���� � ��� � �

]J�8�:3�)3,3���-���479-�� & 7���� & )3,3������=�9> � & �:3f*�<G��C*��LI�zA!�r6#<O&��C� �2� & �<OK(��d7�� �����+79-�7#�+O&��+3�� ��.(1�����#�;79-A?7#���+3)�.*�d79A 3�� � & 7<�D� & f6879-4(+79I+-��21NG�<*��������<3D�9>>� & fG;793)� �d7���I�fA!)*,5�)O5)i��� ���06�<-0/XB��/� & *������-�79OK687#����<3����!���CAcG+(�� <*f7#�+O&�� �PB��9*,D4���� & ���C-��959/CYN7#�+O�� & (+38������C(K*.795� � & uO�26�<-�CG+A���-�8�8>?�.*H(+-:/3,(K*H6��:6879I+-F3H/b3)��<Ac3o7#�+O7����PB��C*,DE3 ���%� & W>@(��,(+* 8Y;7#�+Oj3)���4Ax(+-=7�� W5C*�d7��,-:/������<* <793 )O�7rBL79*����)3,3��9>� & '�:3,3H(�<3)Q

���� � �#$ � � � � � � � � ' %� � � � ��� � ! ' � � �#$ � � �

%'& L>��9-4-��rB���+5oG+-=7#��>��C*D���C(+*H3 <30� & 7��$A!�:5 & �G�����-�.*��4I+(1���� �F7#�A)O+(��<7�������;79-bG+* �95C*.79A �:3$3HG����� ���d79-:-:/�C*�����-� <O � ��BL79*HO�7k3M/N3)��)A?3�G�<*H3,G����� �:6#&�9>'3H(+*H6��:6879I��4-��/�P/CQ % B��,�P/bG�)3A�9> ���C(+*H3 vG+*��C5C*,79A?3X79*��4O���-��� �><O_Y�����,�#� 7"3HAg78-4-'3 �<79-�8Y�� & e3 ������KO+��� 7hAU(�� & IK* �V79O�<*c3 �d78-�9Q � ��B�)6#<*)Y � & 9�PB���P/bG�)3�79* :���CA?G+7����:I+-�8Y_7#�+O � & lO��:i�<*������<3�79* :���#�(���-�.*����+3����8Qxy�<-)687#�-�(�<(+*H* ��<(+-:(+A � �CG���<379*��4O���-��� �><O ��� % 79I+- � >��9* d7#� & �P/NG�9Q* % /bG� �C� qL* d7<�����#� �9>5����$��)B ���C(+*,3�9Q %'& "3 ��+5C-� ���C(+*,3�"B��C(+-:O >����<(+3�G+*��4A?79* �:-:/ ���3H(+*H6��06978I��4-��P/VsP*�<-=7<��<O:�:3,3H(�<3)YbB��/� & 3,G����� �><OgG+* )* <\E(��:3 �/��<3SO�)G���+O����K55����� & ���-����+O�)Og-�26�)-�8>G� & (���C(K*,3 8Q�3N(+5C5�)3�� <O�3 ���K5C-�[s;���9(+*,3�JAg7�� <*��=79-��43 �:O���-��� �><O ��&� & =��78I+-�WB��/� & 7#� � 3 �4��� & �;*,3)�5���C-4(KA!�_Q%3N(+595�<3)��<O 79G+G+*��CG+* �47����GK* <*�<\E(��:3 �� ?A?7�� <* �479-$B��C(+-:O"I�?3�<-���� <Oh>@* �CA� & 9���)A?3�O�����#� <O IV/ � & k3�<\E(���-� �=79-u-� � ��)*,3 � � �+Y � £ �+Y � q �KY � t �+Y � R �+Y�I;793�<O+�#� � & 7d687#�:-=79I��:-��/�P/:�9>0211�43)�����K5����C(+*H3 '�9i.)* ��+5C3<Q

* % /bG�j�N�lqL* <7������� �9>'7k>@(+-4-0/ ���-� <5C*,7���)O �<(+*H* ��<(+-:(+AkQ � * )-=7�� �:6�)-:/�3�<-:>=sJ�����-�.7#����)O ���C(+*,3�GK* �C5C*,79A B��C(+-:O ��C� <5C*,7���a3H(+*H6��:6879I��4-��/�P/VsP3,G����� �>�jA?7�� <* �479-LB��/� & �#� & )*lG;79*��,3!�8>J7 ���C*,A?79-���CAcG+(���)*Ms¢3 ��������j7#�+O ���CAcG+(���)*MsJ��+5�����)* ��+5,�)(+*,*����<(K-4(+A�YT7#� & ��)6���+5�7F�����C*HO����;7<��<O�G+* �8s59*.79A�Q � � �:-4-:(+3��,*.7�� �:6�g3 <-0>=s;�����-��7#���<OB�<(+*H* ��<(+-:(+A 3 )\E(������F���9(+-4O�I�9���#� �;5C(+*�<O �C(����9>A?7�� <* �479-�3 )-��� ��)O�>@*��CA ���)A?32��� � & &��78I+-�c>@* �CA � � �F� & * �9(+5 & � 3 �KY�G+-:(+35� & 7�CG�� �����+32�9>G��C3H3 �4IK-�'3,(KI+3 )\b(���-� ���9(+*,3�zA?7���)* �479-+O�����#��)OgIV/ � % �+Y � � �+Y � � �+Y � � �X7#�+OcG��93,3 �:I+-�'GK*.7#�[s� ���<79-+G+*��w§��� �.3S3,(+I+3H(+A�<Ov(��KO�<*6� & uO�)3 �45#�;7������� � � �Fp O�<G���KO����+5'���4� & z7#�<79O�<A����'-)6#<- Q

%'& �-)6�)- �9>fO���.7#�4-$7#�+O � & :�;7��.(K* :�9>6� & �Ag7�� <*��=79-^3 )-��� ��)O"3 & �C(+-:O �9>����C(+*H3 lI�:�d79*�)>@(+-:-:/79O;78G���)O ����� & x7#�d78O�<A����-�26�)-�7��+OF21NG�<*��������5�8> � & �3��,(+O���C�,3l{ 8Q|5KQ:Y����C-:-�)5�(��+O�)*,5C*,79O+(;7�� <3)Y(����06�)*,3 �/�P/�59*.79O+(+7���?3��.(KO���-�.3)Y���+O+(+3)�.*��=79-6<AcG+-��/#�)3<Y�* ���-�.*M/ ��+O��:6��:O+(;79-:3�I����+5e*���,*.7#���<O�>��9*��2B �d79*��<*H3��[Yz7��+O � & eI;7#��DE5C*��C(��+O�Y8�.*.7�������+5+Y�7��+O [1KG�<*��������F�8>�� & 9��<7#� & ���K5 3��.78i$Q 0e7��E/

) � �

Page 166: Practical Architectures for Survivable Systems and Networks (Phase

����4���: �Y1��K02- �+13*+<>-�:�� v�!�'�n���$%��'��"���L(o&�V z �"&�sN�"��$c$%��'�s%#+��'�s�!���s���( z ���������!���(������ } �����3� ) �

&N�b��'��"�Ms����>�"��nF!�'���� } ����=� ��� v�!�'�n���$%��'��"���L(o&�V l&�VW�RXY����� � '�sN��'��M�M�"��'�s z ���������!���(������ } �����3� ) �

&N�b��'��"�Ms����>�"��nF!�'���� } ����=� ��} (U����� V?&����3&N("(U�������tV?&�����&>Xo��&�'=�

y v�!�'�n���$%��'��"���L(o&�V l�I(U���M$ � '�sN��'��M�M�"��'�s OP'��"�Ms����>�"��n[$S�>�������L��� } � ��3� ) � d��!I��'�&���Xb�LnI�����S����!�sN���b��&In��]�

� v�!�'�n���$%��'��"���L(o&�V m �3�M���>����'�sSl�I(R�"�M$S( z ���������!���(������ } �����3� ) �&N�b��'��"�Ms����>�"��nF!�'���� } ����=� ��

� v�!�'�n���$%��'��"���L(o&�V u��M�RX�&N��_��'�s z ���������!���(������ } �����3� ) �&N�b��'��"�Ms����>�"��nF!�'���� } ����=� ��

l OP'����"&InI!��8����&�'[��&T(�!�������>�����������R�9� �8&�'=�8�M���"(�d y �=���I�"�M� ) } � ��3� ) &�� ���"�������>��(MdI�"��(�_I(MdI��s��"�MsN��&N!�( �M����$c������(

l l�3���M�Qp3�x�o�������>��( y �=���I�"�M� } ����=� ) &�� N�l l!�������]�����������R�F�b��N!����"�M$c�M'���( y �=���I�"�M� * } ����=� ) &�� N�l l�I(U����$%�L�x�~�8p=�M����'��8����( y �=���I�"�M� � } ����=� ) &�� N�l l�I(U����$%�L�x��������&���������( y �=���I�"�M� � } ����=� ) &�� N�l � �]����!=�>����&�' y �����������L� y �=���I�"�M� � } ����=� ) &�� N�l l�I(U����$ ��������������� ��!�����( y �=���I�"�M��( �d � } � ��3� ) &�� ��� �~nI�>��'��M��n[��&N������(o��'�(��I(R�"�M$S(MdI'��8�RXY&��"_(�d v�&�����&>Xo��&�' } ����=� ) &�� N� ^

n����"������(���(�dI���������Q�"���8��!��"��d�(��I(R�"�M$ ��'�n z !���(U!��q����������&Ns���������(�&�VW�RXo���"�~��'�s���'����M�"��'�s=d�8�"��

` �~nI�>��'��M��n[��&N������(o��'�(�!��"�����>���������Q�R�Nd v�&�����&>Xo��&�' } ����=� ) &�� N� ^(����M!������R��dI��'��8�"��I����&�'+dI�������L���������Q�R�Nd z !���(U!��q����������&Ns���������V2��!��Q�b�"&����M����'��M��d�M�"�"&������M&��"����� ����'�s�M&n���(�dI�8�"��

`~(U�q&�V�V?&��"$S���r$c�8�"��&In�(oV?&N���8�"�Q�"������� v�&�����&>Xo��&�' } ����=� ) &�� N� ^�N(U�3���8�"(o&�V (�!�������>�����������R� z !���(U!��q����������&Ns���������

e gh��'���sN�M$c�M'��o&�V nI�M�N�M��&���$c��'N��d��!������Q�R� v�&�����&>Xo��&�' } ����=� ) &�� N� d�M&�'����"&�� d���L(U_[��("(U��(�(�$c�M'���d�!�$S��' z !���(U!��q����������&Ns���������V2�N� ��&N�"(�d��&N��!�(U�b&��3�M'I�P(U&N!����8��dI�M�"��

� z ��&���&��R��3�tn��M������&N��$c�M'��b���"&�|R���8�"(�dI��n���������� v�&�����&>Xo��&�' } ����=� ) &�� N� dXb�������8&N���L���3&����>�"��'�sA�"����$S(�dI��(��=���8�L������� ��'�����s����>����nFXb������� (����!���'��8��"&���!=(R�"�Qp=���>�"��&N'F&�VK&��3�M'���(�&�!����8�q(�&�VW�RXo���"�

���������x� �3l!��"�����>���������Q�R� y !����"���M!���!�$ y &N$%�3&�'��M'��"(

) � �

Page 167: Practical Architectures for Survivable Systems and Networks (Phase

79OK687#�-�.795�<3E�d7#�e* <3H(+-�z>@* �CA ��C� <5C*,7�����+5c* <\E(��:* )A!��C�,3W>��C*u3,(+*M6��:6879I��:-���P/j7#�+OF�/�.3u3,(+I�� ��+O�<Oh7��Hs�.*��4I+(1��<3x3,(�� & 793X* <-�=79I��4-��/�P/CY`3 ��<(+*���P/9Yf7��+O G�<*H>��9*,A?7#����8Y d78*,-:/$���7 � 3��.(KO���-� ��3l-��0>�9Q � �rB�26�<*)YA?7#�V/A�9>�� & o3H(+I��.-�� ��<3"�8>�� & o3H/b3�� <A�O�26�<-�CG+A���-�SG+* ����)3,3z{ 8Q|5KQ:Y-��<79A ���CAcAU(�����d7�� �����x>¥7��4-4(K* <37#�+O � & XG�)*H68793 �06����<3H3'�8>�3H/b3�� <A 6N(K-���)*.79I��:-��/����)3���7#�KOnAg7��E/9�9>"� & 5�:O����93H/����<*,793 �<3E�9>�G+*��1�)(+* [sA���-�dYG����� �;5C(+*,7�������_Y^7#�+O �CG�)*.7�� ������O��9���#��I�����CA!cA�d7#����+59>@(+-0����3��.(KO���-�.3X(��-���:- � & 2/ & 7r6#5V7#���<Oa3H(���������-� [1KG�<*��������8Q

� FAg78D#7UO��:3��������� �����%���%� & ���79IK-�FI���PB����k>¥79A��4-�=79*���P/xB��/� & G+*��C5C*,79A?A����K5X-47#�+5C(;785�<3'7��+O�CG�<*,7�����+5U3H/b3)��<Ac3 ���7���� & 7#�+O�Y+7#�+Oa7UO��<G�<*'(��+O�<*H3��.7#�+O���+5:�9> � & JG+* ������:G+-�)3�� & <* ��9>G���&� & �#� & <* & 7#�+O�Qg]J�'�43(���#�x79O�)\E(;7���4� & 7���3��.(KO���-�.3 & 7d6�cA!)* <-0/�I���� 21NG��C3 )O ����Ag7��E/�O��:i�<* ��-�3H/b3)��<Ac3J7#�KOn-=7#�K5C(;795�)3<Qo]J�E�43o61�/��79- � & 7�� � & )/�(��KO�<*H3���7��+OF� & �>@(��+O;78A!��C�.79-43 �9> � & �C3�x3H/b3)��<Ac37#�+O?B & 7����43S* d78-4-:/A�����<3,3,79*H/%����� & o>@(��.(K* 9Q %'& (+3)Y�� & WG+*�<* )\E(��43����)3��C*����-� <5C*,7���)Og(����/�.3f3 & �rB����� � & :��79I+-U>��C* � � �7� & * �C(K5 & � R ��79*�4��� � & l-���+5a*,(��$���#�'�����)3,3.78* �4-0/F� & c3)��7#�KO;79*,O$���9(+*,3�<3� & 7��8[1��:3������bO;7d/!��!� & ��:*L* )3,G��� ���:6#J79*�d793)YKI+(���*.7�� & <*����C(+*H3 )38�C*L(�����,3��9> ���C(+*H3 <38� & 7��L3��.*�<3H3'75C*,793,G'�9>�� & S79G+GK* �CG+*��=7�� T>@(��+O;78A!��C�.79-43)Q$m )6#<*�� & <-<3H3<Y�[1KG��C3H(+* ����o3 �CA��A!�bO�)* �G+* �95C*.79AcA����+5-=7��+5C(;795#<3 �43 & �45 & -0/gO�<3 �:*.79IK-�9Q

]PO�<79-4-0/CYN7#�a7#�d78O�<A����FGK* �C5C*,79A �������C*,G��C*.7<�����K5x3,(K*H6��:6879I��:-��/�P/l3 & �C(K-4O & 7d6�=)-�<A���-�,3 �9>^3,(+*M61�06Vs79I��:-��/�P/g7��+O7��,3�3,(+I1����KO�<Ok* <\E(��:* )A!��C�,3oO��43)�.* �:I+(�� <O&� & * �C(+5 & �C(��o7:�����+3 �:O�<*,79I+-FG��9*�������&�9>G� & I;793����9�<(+*H* ��<(+-:(+AkQ�];� 3H(�� & 7#�B�4O�<79-'B��9*,-4O�Y�� & �C3 �* )\b(��4* )A!��-�.3?B��C(+-:O I�e78O+O+* )3,3�<O+�� � & 211�:3�����+54���C(K*,3 )3zO�<3 �:5��;7�� <O�IV/ � � �4� & * �C(+5 & � R �?7#�+O � % �4� & * �C(+5 & � � �4��� % 79I+-� � Q

];� �����-�.*,793��<Y�3,(+*M6��:6879I��:-���P/ �43?79-4A��C3)�4��)6#<*v78O+O+* )3,3�<O+���bO;7d/CY�7#�+O 3���)(+* �/�P/ 7��+O *�<-��479I��:-���P/79*�,�P/bG����<79-4-0/ 3HG�����=78-�P/ 3,(+Ib§�����,3<YJ7#�KO+� & �� �#�+-:/ ��� 7�>�2B�(����:6�)*,3�����<3)Q 31�:A!�:-=79*H-:/9YL3 �8>@�PB�79*���K5������<*����+5JA?7d/UI�8��79(+5 & ��793�7=���C-:-��� ������A�9> �����C-:3<YC*,7�� & )* � & 7��l793�7=��� & )* ��C�S3�����9>�G+* ������:G+-�)3<Q� 3�7J*�<3,(K-�dYC>@*��CA�7GK*.7#� �����<79-N6��)BoG������-�dY-�/�TB��C(+-4O�I��6�)*H/lO�� ���<(+-/� ���7#� & ��)6#u7J>@(K-4-:/'��C� <5C*,7���)O79G+GK* �V7#� & 783F7#� ����<*�<A���-��79-^A��NO�� �>�d7<�����#� � �&211�:3�����+5&���C(+*,3�U3��,*,(�� �.(+*�<3)Qx���,� & A�#� & <* & 7#�+O_Y���B��C(+-4O�I�v*�<-47����06�<-0/ d793M/ � �,����� �=79-:-:/ ���-�.*��NO+(���j7�3 ���K5C-����)B ���9(+*,3�j79O+O+*�<3H3 ���K5,� & %���)A?3O�����#��)O?IV/ � 3 �(���A� & 8��79IK-�9YC7#�+O:� & ��!26��C-06�8� ��BL79*HO�� & 'O�<3��4*�<Ol5��V79-1�9>�7���� & )* ��C����C� <5C*,7���)O�<(K*,* ��<(+-:(+A�Q

%'& (+3<Y��C(+*zI;793 ��X*�����CA?A���KO;7�������9�43����v3)��79*)�W3HAg79-:- B��� & � & X3 ��+5C-�(���C(+*,3�x>����<(+3����+5!���,� & � 3 �4�/��<Ac3�A��C3���3,G����� �>�d78-4-:/?* )-=7�� <O7���l3H(+*H6��:6879I��4-��/�P/CYN7#�+O7� & ��9��6#<* ���:A!E���:������C(+*,795�J>¥7#�)(+-�P/A�<AUI�<*H3'� �n79-:-��rB � & %��������)G��.35�9>'3,(K*H6��:6879I��:-��/�P/F��� �C3,A��C3 8YTG�<*H68793��:6#<-:/�B��C*HD���+5,� & <Ac3 )-:6�)3���-� �!� & xI+*��V79O�)*F7#�<79O�<A����G+*��C5C*,79A�p B��/� & G+79*�� ���<(K-=79*�<AcG & 783 �43 ���9� & UO�<3 �:5��,�8>"�CG�<*.7<�����K53H/b3)��<Ac3�7#�KO ����PB��C*HD���+5+Y�7#�KO � & ?(+3 %�9>'G+*��C5C*.78A?A����+5a-47#�+5C(;785�<3X7#�+O 3��9>@�PBL79* &��+5�����)* ���K5���� & ���:\b(�<30� �W7�� & ��26�S5C* <7���)*�3H(+*H6��:6879I��4-��/�P/CQ ];�'� & �G+*��1��<3,3)Y#� & fA?7���)* �479-#��2<7#� & ���C(+*,3���8i.)* ���K5A?7r/ � & 7#�+5�k3 �CA�)B & 7<�dY8����<-:(+O����K5 � & �Ag7�� <*��=79- <79*,A?79*,D�<O�>��C*:� & k3 ���K5C-�7�P/bG�[s�� ���C(+*H3 ���3,(K*H6��:6879I��:-��/�P/up 3 �CA���8>+B & ��� & Ag7d/=����+O5� �WI�fO��:3��,* �4IK(���)OU79A����+5 ��)*���7����xGK* <*�<\E(��:3 �� ����C(+*H3 <3)Q

����4�9>�� & cA!�C3)�J>@*,(��/�,>@(+-T79* <793�>��9*�3)�.(+O���-�xGK* �w§�����.32���V6��9-:6�)3'� & l* �CIK(+3�� � �>�<7������� �8>��CG���bs3 �9(+* ��c3��9>@�PBL79* 8Q %'& l6879*��� �P/F�9>L79G+G+*��V7#� & )32�:3�����C*,A��C(+3)YH� & :� & 79-:-���+5�<3�79*��(��+-�4A����)O_Y_7��+O� & 5�CG+G��C*)�.(����/���<3o>��C*W3H(�����<3,3M>@(+-TG���� �.*,7�������F���-� �!� & x* <79-`B��C*H-4O�78* X6#<*M/,[1����� ���+5+Q %'& UI�<3)�* )3,(+-/�.3JB��4-:- �>�+O ���+3)��7#�-�(+3�!�#�$� & � <I�Qvq��C-:-=79I��C*,7�������+3zB��/� & �#� & <*,3(�<7#��-d79O ���9���#�C� ���E(;79-�4AcG+*���6#<A���-�.3)Q

� �FGK* <3���-�dY.���&�CIV6����C(K3E��[1��.I��1�CDE3��<7#�F�����-�.* �:I+(�� xO��:* �� �.-0/9� �!� & A���-� ��+O�)O�I+* <79O�� & �9>"� & �C(��,-����<Oc3,(+*M6��:6879I��:-���P/5�<(+*H* ��<(+-:(+A { �#� & <*�� & 7��gG�<* & 79G+3�� & �43S* )G��9*��dYEB & �� & ����� & �;*,3)�LG & 793 E�9>� & xG+*��w§��� � & 793zI�����G+*��4A?79* �:-:/!��������<*���<OnB��/� & � & X>@(��+O;79A���-��78-43u*.7�� & <*�� & 7��,� & XO���.7#�4-:3LpB & �� & 79*�/#��E���l>��C-4-��B ��9� & X3�������+OeG & 793 d�2Q � �rB�26�<*)Y�� & <*�x79*��6879*����C(K3'I����CDE3 � & 7�� �d7��eI�

) � �

Page 168: Practical Architectures for Survivable Systems and Networks (Phase

21��,* <A�<-0/�(+3 2>@(+-�����;-:-����K5E��x3 �9A!��9>>� & L5V79GK3`p >��9*0[1+78A?G+-9Y979O+O+*�<3,3����+5W3 ��)(+* �/�P/j{�9Q�5+Q0Y+}��C�C�8�=�2Y� 7d687h3���<(K* ��P/ 7#�KO 3���<(K* nA��CI��:-�&���NO��{ 8Q|5KQ:Yu}��9�C�8���9*<YfB & ��~7d687#�4-479I+-9Y'}��9�K�2���[Y�7#�KO 3 �8>@�PB�79*���K5������<*����+5�{�9Q�5+Q0Y�}��C�K�<�=�2QF3N(+*HG+* �:3 ���K5C-:/9Y0� & <* gO��1)3A���#�x3 �<A ���nI�j7#��78G+G+* �9G+* �47���)-:/�3 ���CG�<OA��NO�)* �"I����CDF���h>¥79(+-/�'� �C-�)*.7#����9Y$79-� & �C(+5 & � & <*�v79*�?3��CA!c3 �:5���� �>�d7#�-�'§��C(+*��;79-S79*�� ���)-�<3)Y`3,(�� &793f}��C�8�C����O��43)�.*��4I+(�� <O>¥79(+-/� ���C-<*.7�����8Y87��+OU7#�'d78*,-:/WI����CD��#�XG+*��������4G+-<3S} �r�8�-� & 7���79-� & �C(+5 & �C(��G�9>G+*����-�H�43_3)���:-4-9(K3 )>@(K- Q ¡ 78*MsP3��45 & � <O5����NOJG+*��������4G+-<3.� ��+O=� �u*�<A?7#���J5#�1�bOJG+* ������:G+-�)3�>��C*�)6�)*<YwO�<3HG��� � & 7#�K5�<3(��� � �� & ���9-��C59/9Q �E�rB�)6#<*<YG� & �(��+O�<*H3��.7#�+O���+5e7��+Oh79G+G+*�����47������� �9>�� & �93 �G+*��������4G+-<3��:3& �:5 & -:/WO�<G���KO���-� �#�'� & ��:*^I����+5��4-:-4(+3)�.*.7<��<OIV/(���#���<*�����21K79AcG+-<3<Q ¡ (+*�� & <*HA!�9* 9Y ���� & ���C-�C5���d79-� & 7#�K5�<3 �9>@����9� ��+O ���lA?79D#(�CG1���4A�� � 7�������v78OK6�����=�9I+3 �C-�� 9Q

0e7#�V/7�:A?G��C*)��7#�-�o79*)����<-�)3�3 & �C(+-4OaI�Ag7#�KO;7����9*H/v*�d79O����+5U>��C*o7��E/v3��.(KO���-�.3z3 �<DC���+5?7�O��)G�)*(��+O�<*,3)��7#�KO����+5KY$\E(��� v7a>�)B �9>LB & ��� & 78* ����� <O 21NG+-�����/�.-:/F��� � & �:3X*�<G��C*��<Qh{ 31�!� & vmE����)B��C*Zs� & /hy�)>�)* �����<32���/��<O$��� � GKG���+O��01�tUQ�� �E�rB�)6#<*<YD��(�43(�)-�d78*�� & 7���3��CA!���������)O+3(���aBo* �� c7#�(+GNs ���8s¢O;7�� �� 21��.I��1�9D$� & 7��2���C(+-:O I�g(+3�<O >��C*'� & !���C*�vG��9*�������$�9> � & ?G+* �9G��C3�<O�3H(+*H6��:6879I��4-��/�P/�<(K*,* ��<(+-:(+A�Q��0)* & 79GK3 � & �43o* )G��9*��'B��4-:-�3�<*H6#U793 � & I;793 �:3�>��C*'3,(�� & 7�I����CD�QS���9� & (�#� & )* & 7#�+O_YI��1�CDE3W79* 2�9>@����F�CI+3��C-� ��xI�)>��9* 2� & )/k79*�xG+(KI+-��:3 & )O�p B & �� & �43oB & /,� & �43u* )G��C*)� & 783z>����<(+3�<OG+*��4A?79* �:-:/ ���"GK* �������4GK-�<3�7#�KO � & ��4*(��KO�<*H-:/����+5�A��#���0697<�����#�_Y 793B�)-4-S793B & / �/�'�43(�4AcG��9*���7��C�=� �3��,(+OK/7� & -��� <*,7��.(+*�9Q� �N>��C*��,(��;7�� <-:/9Y"� & jG+*�)687#�:-����K5eA���-��79-��P/�79A����+5�A?7#�V/�/��9(��+5�)*�* <3�d79*�� & <*H3v7#�KO�O�)6�)-��CGbs

<*H3,�:3a>¥7��4*,-0/ �,* �C5C-�NON/�� ���nB & �� ��9���CA!)39� � <79*,-��)*aB��C*HDb3)� � ]¢>:�/�9�43 � � �9��� � & � )I ���bO;7d/CY��,��)6#<* [1��:3�� <O ��� � & G;783��dQ � 0e7#�V/ [11�,* )A!)-:/ �4AcG��C*)��7#�-��B��9*,DE3 ��� � & -���)*.7��,(+* ����+O����I�v>��C*,5#�#� � ��_Q {�����7)i��C*��:� ��* <3H(+3 ����.7���a3 �9A! & �43�� �C* ��d79-:-:/h3 �:5���� �>�d7#�-�:2i.�9*��.34�:35� & � �43Ms���9*H/ �8>Jq��CAcG+(�� <*�31��<(+*���P/���*��w§��� �dY�B & ��� &�& 793:�)* d7<��<O q�tzsZy�� 0�3��8>z3�<A����;78-LG;79G�<*H3<QB31�& � �,G_���9�83 ��<-=78I_Q �)3<Q�(��<O+7r6��:3<Q <O+(��wG+* �w§�����,3�� & �:3�� �C*H/�>��C*�>@(+*)� & )* ��K>��C*HAg7�� ������Q��

� 3T7#�A�C(��,5C* �rB � & �9>�� & �;*,3)�Hs¢G & 793� )i��C*��D���A�C(K* � y �jG+* ��§�����<YCB��� & � & L3 & )G & <*HO����K5=�9>��$79(K-��79-�� � 79Da7#�KO � ��C*H5�A3E/N*HA!�93F7�� � & � ���:6�)*,3���P/9�9>:0e78*H/b-=7#�KO_Y�7!����[sP3�<A�<3�� <*����C(+*H3 5�8> % /bG���������<Ov79I��r6#WB�783���79(K5 & �'IV/vm <(+A?7#���j7<��� & � ���:6�)*,3���P/!�9>W0e79*M/N-47#�+O!���%� & z>¥79-:-�3 <A�<3)��)*8�9>�r�C�9�KQ %'& (���C(K*,3 '���#� <3u79*�X7d687#�:-=79I+- ��a7����CGV/N-)>@�'>��C*HA ���Ns¢-����{ & ���.G_� �C�wB'B'BQ �<3H- Q�3,* ��Q ���CAg����<(KAg7#�����8(+AcO_Q & �,A?-=�2Y+>@*��<-0/a7d687#�4-479I+-�z>��C*o(+3 2<-43�)B & )* 8Q %'& XI+793 ���C(��,-����W>��C*8� & (���C(+*H3 '�43o793'>��C-:-��rBo3<�

�9Q�];�C�,* �bO+(�� �����#�k7��+O �r6#<*H6��)B�bQ�3N(+*H6��06978I��4-��P/VsP*�<-=7<��<O?* �:3,DE3�NQ�y �:3,DE3������-����E(�<O_Y�7��+O %'& * d7<�.3� Q�3N(+*H6��06978I��4-��P/c* )\b(��4* )A!��-�.3�bQ�t� �>�����������)3����7211�:3�����+5l3H/b3�� <Ac3�NQS�F6#<*����CA����+5:� & <3�XO� �>����������)3���bQS�F6#<*����CA����+5:� & <3�XO� �>����������)3W��NQ � * � & �������,(+* )3u>��C*'3H(+*H6��06978I��4-��P/k��NQ � * � & �������,(+* )3u>��C*'3H(+*H6��06978I��4-��P/v��d�KQ�y )-��479I��4-��P/:��aG�)*,3,G��� ���06��9�CQ�31��)(+* �/�P/7���aG�<*H3,G����� �:6#�r�NQ � *�� & �� ����,(+* )3u>��9*'3,(+*M61�06879I��4-��P/?��d�KQ�]PA?GK-�<A���-� ���+5x>��9*'3,(+*M61�06879I��4-��P/� � QSq������)-4(+3������+3

) � +

Page 169: Practical Architectures for Survivable Systems and Networks (Phase

];�vG;78*������+3HG��4*�<OvIV/�� & X0e79*H/b-47#�+O&���C(+*,3�J7#�+OgIE/�� & )i��C*)�.3��8>^�$79(+- ��79-�� � 79D4���?G+* �9A!�#� ���+5� & zG & 793 [s;����o*�<G��C*��<Yb*�<-47���)O!���C(+*,3�<3SB�)* ���79(+5 & �SIV/ % ���V/c£�79* ��<3f7��6� & � ���06�)*,3 �/�P/:�9>_�0����Ns3H/b-0697����=7KYN7#�+OjIV/vt��C(+5�£��:*,OKB�<-:-_7#�KOatJ7r6#J];���r6�7<�8� & � ���06�<*H3 �/�P/&�9> % �����)3,3�� �(���r1b6��4-:-�8Y1��� & �>¥79-:-?�9>f�r�C�C�NQ83N(KI+3 )\b(���-�.-0/CY_7l3 )A!��;79* ��� � & �43o3,(+IE§�����zB�783 �.79(+5 & �uIV/e£f-=7#���J£L(+*�� & 79A 7<�� ��C*H5��=7 % �� & Y �� � & JB����-��)* �9>��8�C�C�KQ]LAx(+3��W79O+O9� & 7���� & '0k79*H/b-=7��+O,���C(+*,3�2���#��)3F79*�(� �g3��CA!([11� ��-�FAX/ ��B��kG�)*,3����;79- 6���2B �9>B & 7�� �43 �:A?G��C*��.7#�-�0� ����<7#� & YCB��� & �����K3 �4O�<*.78I+-�8)A?G & 793 �:3 ����I;783 ���)3<YVG+*��������4G+-<3)YC7#�+O4[1KG�<*��������8Qy�65>�������+5 ����Ax/e6��)B � & 7��=� & �43WAg7�� <*��=79-^O���<3(���#�J-��+O �/�.3 )-:>6���a77���1�CDEI��1�9D ���C(+*,3�9Y^] & 7r6#���-� ��-������;79-:-:/U-)>@�S5V79GK3���!� & z3H-��4O�o6#<*H3 ���#�+38�9>�3 �CA�E�8>?� & u-�����,(+* )3J{¥3H(�� & 793S3 ��<(+*���P/?7#�+Oc>¥79(+-����9-�<*,7#����v3,G����� �>�)3��2YL793�7#� �������C� �:6#v>��C*�7#�V/�-����,(+* )*�(+3 ��+5F� & <3 aA?7���)* �479-43(���h79G+GK-:/ & �43A�9*& )*��rB���D�����Bo-<O+5#9Y 7#�KO�793J7#�,��������-���06�x>��C* � & x3��.(KO���-�=���gO��45!���-���%� & U-���)*.7��,(+* 8QX0a/,�rB��G�<*,3����;79- [1NG�)* �������9�<-d79*H-:/ ���K>@(+3�<O�Ax/ 0k79*H/b-=7��+O�-��� �.(+*�<3)Q ¡ �C*A[1K79A?GK-�9YS]5����<-:(+O�)O�3��CA�>@(+*)� & )*zA?7���)* �479- ���ntJ7d6��4O �z(Ni�A?7#����3zI�d78(����0>@(+- B��C*HD ���e5C*,79G & ��d79- )*,*��C*MsJ���C*H* �� ����+5%���NO�)3u>��9*-=78*,5�)* �z79AcA!��+5�O��43)��7#����<3�� & 7<�%�:3����#�%����<-:(+O�)O ��� � & ���bsP-����j3,-�4O�)3<Q~]xB��C(+-:O �����%[1KG��� �3 �9A!�����A)-43 A� �%��<7#� & 3,(�� & * )-=7�� �:6#<-:/�(��KD�����B��hA?7���)* �=78- Y�79-� & �C(+5 & ] & 79O�7g>¥793 �����;7<�����#�kB��� &��I���<79(+3�!�9>���,3F61�:3,(;78-S3��4AcG+-�����/�P/e7��+O"AX/�G�)*,3����;79-S793H3 �����=7<�����#�nB��� & �z(Ni�A?7#�_Q � -:3 �+Y � �4*,5#�4-� -��45#�C*U3.7<�%���B��/� & A!j>��C*:� & "�C��� & �)-=793H3lG�)* ���bO_Y831��)(+* �/�P/ ��� �0<*H3,G��� ���:6#9Yu79O+O����+5 & �434�rB��6�)*H/~3��45���� �>�<7#�-�aG�)*,3 �#�;79-�[1KG�<*��������h793vB�<-:- Q %'& 7��aO��43��<(+3H3 ���� �437�d78G��.(+*�<O ���+-0/ I+*����5+/+��3,(KA?A?79*H/9Q$];�?5����)*.79-�Y-� & oO��:3 �<(K3,3 ����gG�<*����bO+3�O+(+*����+5(�<-4793,36���:A!fB�)* z6#<*M/?GK* �bO+(���� �:6#9YbI���d79(+3�� & )/l79OKO+* )3,3 )O%� & u3HG����� �>����������<*��+3��8>�� & '3��,(+O���-�,3 9XB & ��� & 79*� ���#��d793��4-0/5�<79G��.(K* <O!����3H-��4O�<3 ��W6�)*.79-:- Y�]?�d7������#��3��,* <3H3 �9>@� ��5����C(+5 &x& �rB >¥79*�7dB�7d/(� & f3H(+*H6��:6879I��4-��/�P/FG+*��CI+-<Ac3�78* �>@* �CA & 7r6���+5�����CDEI��1�CD?3 �C-:(�������+3)Q

��� � ����� � � � ��� � ' % � � � � � � ' � � � � $ ! � !#" � ! � � � ��� � � ��$ � ' � ��� � � � �� � !#"

31�CA�u(����:6#<*H3 �� ��)3L7#�KO&�#� & <*����+3)����,(�������+3S79*�E�9i�<*����+52�C*������-��)A?GK-=7�� ���+5(���9(+*,3�<3��.79(+5 & �8�#�NsP-����6��=7�� & �];�-� <* ����dY-����<-:(+O���+5W7o>�)B�B��� & O�)5C* ��G+*��C5C*.78A?3)Q %'& )* o79*�LA?7#�V/�G��#� ��-���479-EI���� ���.3<YE783� & LAU(+-/���:A!)O��=7�� �� & ���9-��C59/'�:A?G+*��r6�<3`B��� & *�<3,G��� � ���W79(+O���+Y�61�:O���KYC7#�+Ox3 �CG & �43�� ���<7���)Ox5C*,79G & ��<3<���<7#� & )*,3&�<7#� * )(+3 ,���C-:-=79I��C*.7<���:6#<-0/ G+*�<G;79*�<O ���C(+*,3�eA?7���)* �479-43��u3)�.(+O���-�.3&�<7#� 3�� & <O+(K-�,� & ��:** )A!����W3)�.(+O���<3�7���� & ��:*��rB�� �����V6�����������8Y�7#�+O7)A?G+-�r/��)38�d7��jG;79*�� �����4G;7�� E��v3 )-������)Oj3,(+IK(�����,3>��C*J*�)>@* )3 & )*,3���3 ������ �P/ �d7��"I���� ����>@* �CA�7#� �r6#<*.78-4-"�����<* <793 4��"-���)*.7#�2/ap 7#�KO"G�<* & 79G+3()6#�����9A?G+(1��<*o-���)*.7#�2/CQ��=�bsP-�����)O+(��d7<�����#�,��� & <*���.3'A?7#�V/ �9>0� & X79OK687#�-��785�<3z7#�+OkO��43,79OK687#�-��795#<3��9>��[1��.I��1�CDE3u7#�+O9���#�E6#��-������;79- � d7#� & ��+5+Y+IK(��z79-43�����-�.* �bO+(���<3o3 �9A!=� & 78-4-���+5�)3 �8>D�/�.3 �rB��_�* �G��CGK-� ���V6��C-06�)O%���!���C(K*,3 zG+* )G;79*,7�������?\E(����DE-:/lO��:3 ���r6#<*�� & 7����<*�d7�� ���+5 & �45 & sP\E(;79-��P/5� d7#� & s��+5UA?7���)* �479-43��43f-=79I��C*���-����K3 �:6#9Y;7��+Ov6�)*H/7� & 78-4-���+5���+5+Q % ��I�J3,(�����<3H3H>@(+-�Y>���Ns¢-�����E��+3��,*,(��[s� �����x* <\E(��:* )3�26���gA��C* 8�9*,5V7#��� � 7<�����#�U7#�+O�>��C*��� & �C(+5 & �����:�)* <7�����+5=���C(K*,3 )3"� & 7#�4���9*,A?79-4-0/CYI���<79(+3��� & )* JA?7r/?I�=���+-:/?-��:A!�/��)O!��C� <*,7#��� �����+3fB��� & 3)�.(+O���-�.3)Y¤7��+Oa7#�-������4G+7�����+5U79-:-¤G��C3Zs3��4I+-5�CG1�����#�+3 �:3FO�� ���)(+-�<Q %'& �C(+5 & �H>@(+-TG+-47#������+5j7#�+O �<79* 2>@(+-4-0/�O�<I+(K5C5�<O ��+3��,*,(�� �����#�+3J79*�)3,3���-���479-����A?79D#8� & �21NG�)* ������zA��C* f>@(+- �;-:-���+5z>��C* � & o3��,(+O���-�,3<Q ¡ (+*�� & <*HA!�9* 9YC>��9*�Ag7#�V/DC��+O+3��9>0���C(+*H3 )3<Y ���Ns¢-�����FAg7<��<*��=79-:3LAU(K3��uI�J(KG¤O;7<��<O�* )5C(+-479*,-0/%���l*�<A?7#���&� �4A�<-:/9Q

* 0k7�§��C*'��������<*��+3�79*��43 c* )5V79*HO����+5�B & �F�rB��+3'� & ?Ag7�� <*��=79-:3g{@3 �CA�c(����:6#<*H3 �� ��)32�)-=7#�:A G+* �8sGK* �� ��79*M/e*��45 & �,3����a79-:-$AU(+-/���:A!)O��=7����C(+*H3 2B�79*�r�[Y^B��/� &�& �:5 & -��:D#<-� & ���bO � & 7��Ag7<��<*��=79-:3uB��:-4-

) � )

Page 170: Practical Architectures for Survivable Systems and Networks (Phase

I�nG+(K*,-��#����)O �C*&)Ag783 �<(K-=7�� <O_Q 31�9A!e79-�,*,(��:3,A �43?O�<3��4*.78I+-� ���+[1+7����.-0/ � & �3.78A!k3 ��K3 � & 7�� �9G���NsPI��d1j3 �8>@�PB�79*�?{¥3 �231�� �����#� �bQ:�r�C� & 793'I�����CA!J3H(�� & 7#� �4AcG��C*)��7#�-�LO+* �061��+5U>��C*���9Q£�<3 �:O�<3)YVG��<*�* 26���)B 7#�+O:�#�+5�����+5=���C-:-=79I��C*,7�������+3^79A����+5���+3��,*,(�� ���C*H3"���C(+-:O�-�<79OA���(���#�C� ���Ns(�<O%�:A?GK* �r6�)A!��C���9>�G+(+I+-���[sPO��CA?7#��:���C(+*H3 zAg7�� <*��=79-:3<YCG;78*�����<(+-479*,-0/5�0>_O��#��E���� & ���CGV/b-�2>@�A?7#����<*<Q

* � O+A������:3��.*,7����9*,3S79* z-��:D#<-0/:���X3 �)D%���C3��Ms;�<(1� ����+5UA�d793H(+* )3<YN3,(�� & 793 �;* ��+5x\E(;79-� �>)O%��+3��,*,(��[s� �C*,35��� � & &���9A?A���� \E(�)3���>��C*2d793M/�7#�+3MB�)*,3)Y��r6�)*,3��4AcG+-��0>�/1��+5 � & &�����-����-�<Yf7��+O �<(��������K5���C3��,3 � & *��C(+5 & �#� & <*'A��43,59(��4O�)OaA!<793,(+*�<3)Q

* � �C3H3 �9> ��C� <*,7#��� �����+3$79A����+5W3)�.(+O���-�.3S7#�+O:��+3��,*,(�� ���C*H3 �43$7W3 )* ��C(+3TG��#����-���=78-N*��43,D�Y�)3,G�����=79-:-:/�0>H� & (���K3��.*H(���� �C*'O���<3����#�u*�d79-� � E� & 7���� & 3��.(KO���-�.3z79*��3��4AcG+-:/!���#�o5#�� � ���+54�/�dQ

%'& -=783�� �9>H� & <3�2� & 78-4-���+5�)3 �d7#�aI�JG;79*�� �=79-:-:/����9(��-��<*�<O�IV/7�����)-4(+O����+5U3��CA�J-��:6#J-�����.(K* <3 �9*6��4O���#��)-�������K>�)* �����)Oc-�� �.(+*�<3<YE7��+O�* )\b(��4* ��+5���+3��,*,(�� ���C*H3�7#�+OA� d7#� & ��+5793H3 �43)��7#�-�,3D���JI�'7#����<3H3 �¦sI+-�����7U* )5C(+-=78*LI;793��43)Y;7��'-d793)�o793H/���� & * �����9(+3,-0/j61�4752s¢Ag7��4- QV0k(+-/�����<793������C(K*,3 (���CA?Ax(������<7�������+37#�+OJ§H(+O�������9(+3�(+3 E�9> � )Ig3 �/��)3fA?7d/�I�z79G+GK* �CG+*��=7�� '>��C*�O�d78-����K5B��/� & 7#�%��-���4*���<-=783,3<Q � �rB�26�<*)Y� & c*�<-�=79I��:-��/�P/e7��+O"3���)(+* �/�P/nB�<79DC��<3H3 )3:��� � & 4��K>��C*,A?7�� �����F��K>@*.783��.*H(����,(+* )33,(+5C5#<3��'� & 7���3��.(bsO���C�,3WB��4-:- �>�+On-�#�.3 �9>"[1��)(+3 )33,(�� & 793 � & � ];�-��)* �� �7���XAx/92s¢Ag7#�:- ��6879* �47#�-� �#� � & A�C-4O � 0�/O��C5�7<��vAx/ & �CA�)B��C*,D ��* �9(������9Q�];�-��)*,3��,(+O���C�!���#�C�.7#���,3:�d7#��I�a7#�4O�<O IV/ � & 7<�l* ���CA?3)Y$B��� &���K3��.*H(���� �C*,3 �,*H/����+5:� �cD��)G,� & O��:3 �)(+3,3������+3���� ��78*,5� �dQ � -:3 �+YK3��.(KO���-�.3E�d7#��I��*�<\E(��:* <O ����B��C*,D���aG;7��4*,3 �9*8��d78A?3 ����G+*��w§��� �.3oB & �C3 3H(�����<3,3 �43'A��C* =�C*'-<3H3u3�<-0>=s;)6��:O���-�dQ

R$s;)O+(��d7<�����#�nAg7d/kI�xI� � ��)*W>��C*E�C-4O�)* �C*WA!�C*�xO��:3 ���4G+-����)Oe3��,(+O���C�,3<Y^7#�+On>��9*W3��,(+O���C�,3JB & �O��9���#�221NG�����2����I����-� <*��.7#����<O_Qv]J�2�43(+3�)>@(+-�>��C*3)�.* )3,3����+5e>@(��+O;79A���-��78-43�793B�)-4-�793 & <-:G����K53��,(+O���C�,3�5V7#���x* d78-+3,DC�4-:-43)Q$£L(1�"���+-0/5��<*��.7#���A�P/bG�<36�9>����9(+*,3�<3S79* L3,(��/��79I+-f>��C*D���NsP-������9i�<* ��+5C3 p(��K>��9*��.(��;7���)-:/9YbG+79*�� ���<(K-=79*H-:/5� & �C3� ���9(+*,3�<3�� & 7���<AcG & 793�� � zA�<A��C* � � 7�� �����l7��+Og*�<5C(+*H5���.7�������_Y��9*� & 7����d7#�aI�=d793��4-0/?59*.79O�)OaA!�� & 7#����d79-:-:/cIV/7)6879-:(;7�������v3��9>@�PB�78* 9Q�3N(�� & ���C(+*,3�<3z79* F79-43�� & �45 & -:/3,(K3 ��)G����:I+-�=� �:� & d7�� ���+5KYKB & ��� & �<7#�kI�=21NG��� ��<O ���4�����)(+*'*.79AcG;7#�-�,-:/cB & ���26�)*z5C*,79O�)3z78* �� & G+*��4A?79*H/e5��V79-�Y^(K3 <O 793x7�G+* �:Ag78*H/nO����)*,A����;7��C��>��C*L§��CI+3X7#�+O"G+* �9A!�#� �����K3<Qjq & d7�� ���+5 ����+O+32� �G���;79-� � =���+-:/%� & & ����)3��z3��,(+O���-�,3<Q']J�z79-43��?3�<*����C(+3H-:/7���CAcG+-���d7�� <38� & 2� & 78-4-���+5�=�9>$A!<7#����+59>@(+-G+*��9>�<3H3 ���#�;79-?��<*�� � �>�<7�������aI;793�<OeGK* �4A?79*��4-:/4�#�k7��d79O�)A!��J* ����C*HO+3<Q31�������P/XAg7d/ �>�+O:� & 7<��O��43)��7#����'-�<79* �����+5F-�C3 )3�Ag7��E/2�9> � & 'O��)G�)*�79OK687#�-��795#<3"�9> �.*,79O��/�����#�;79-

(����06�)*,3 �/���<3�p B & )* o3,A?79-:-�<*0�<-4793,3H* ���CA?3T79* �5#���)*.79-:-:/XA!�C*�8)i��� ���06�9Yb7#�KOlB & <* ������+3 �:O�<*,79I+--�<79* �����+5:�P/bG����<79-4-0/%�.79D#)3WG+-47#��(�C(��,3 �:O�(�9> �)-=793H3,* ���CAc3<QL£L(�� 2sJ<O+(��<7��������Ag7d/�79-:3 ��>��C* ��X*,79O���d79-�.*,7#�+3M>��C*,A?7�������+3 ���2�����V6#��-������;79-��<-4793,3H* ���CA?3)Q`]¢>+B�L79* 6���uA?79D#6� & SA��C3��0�C(��G�9>�� & �� & 79-4-��+5#<3<Y� & U79OK6����A�9>�£L*H/��w§��C-0>@3,3�����7#�+O �E�����}�� �w��3,(K5C5�<3)�.3�� & 7��E��)B�79G+GK* �V7#� & <3����!<O+(��d7�� �����eB��:-4-`I�* )\E(��4*�<O_Y�B��/� & 7 � G;7#��K>@(+-o7#�KO ���:A! ���#�+3,(+A����K5"G�<*����bO �9>F* ���+5�����)* ���K5+Y�* )3��,*,(�� �.(+*����+5�7��+O�C*H5V7#��� � 7�� �����v*�<O�)3 �:5��_Q0Q:Q �%'& )* ��:3L3�� �4-:-¤7X-=7#��D��9>H21NG�<*��������FB��� & YN7#�+Oj-=7���D��8>H�<* �/����d79- )6879-:(;7�� �����!�9>ZY�� & FI���� ���.3o7��+O* �:3,DE3 �9>^3,(�� & ���� & ���:\b(�<3<Q ¡ �C*8[1+78A?G+-9YNO��1)3 <-����,* �������=<OK(��d7�� �����j3��d79-FB�)-4-.� ��-=79*H5���E(+AUI�<*H3�9>o3)�.(+O���-�.3:��� �#� & )*2� & 7#��* ����2s¢-�<79* ����+5�3 �������+5C3���q�7#��7e3)�.*����+5�3,(KG+G��9*��U3)��78i �����)-4(+O����+59���NsG�<*,3���� ��d7�� & ���+5c793H3 �:3���7��C�,3����CAcG���+3.7<��F>��C*�A?7#�V/&�8>0� & G��#� ��-���479-�*��43HDb3������ � & FB & �C-9Y�� & <*�79*�e3 �9A!�3 �:5���� ���d7#�-�?G��#� ��-���479-oI���� ���.3<Y'>��C*���)*��.7#���B�P/NG�<3%�9>(���C(K*,3 )3<Q � & �CG� � & 7��g3��CA��9>6� & �(����:6#<*H3 �� ��)37#�+O �#� & <*=��+3�� ��.(1�����#�+3F79-:* <79OK/kG+(+*,3H(����K5�*�<A��#��5<-�����,* ������A<OK(��d7�� �����nB��:-4-)6879-:(;7�� � & ��:*aG+* �C59* <3H3 �#� � & "I+793 �:39�8>�7#� �.(;79-3)�.(+O���-�F21NG�<*��������<3 {¥*,7�� & )*7� & 7#��§H(+3��9� &

) �

Page 171: Practical Architectures for Survivable Systems and Networks (Phase

G�<* ����06�<O�I���� ���,35���9� & !���+3)�.*,(������9*,3��[YT7#�KO 3 & 78* !� & g*�<3H(+-�,35�CG���+-0/CQ � �-� �4-6� & ��_Y$B�?68793��,-:/G+*�)>�<*5���Ns¢G�)*,3 �#� ��<7#� & ���K5 ���C(+GK-�<O"B��� & 3��.(KO���-�.3�B & ��78* v3�<-:>=s¢A!�����:687�� <Onp 79-/� & �9(+5 & � & <*�& 7d6�'�<-d79*H-:/gI�����3 �CA�J3��,* ���+59-:/vG��C3�����06�=[1KG�<*��������)3zB��� & 61�:O������<-������K>�<*���������+5KQ

]¢>")-��� �.*��������XAg7<��<*��=79-:3o79* '���?I�U(K3 <O ��n7c3,(+*M61�06879I��4-��P/j3M/b-4-=78I+(+3<Y�B�U* ����CAcA!��+On3)��79*)�����K5A��NO�)3��,-:/j7��+O9� & ��921�� ��+O���+54� & (�9i�<*����+5C3 ���74�<79* 2>@(+- )6#�C-4(1�����#�;79*H/gAg7�����<*)Q

��

��� � � � � $ % � � � � � � ' ��� ! � ! � � $ � ��! � !#" � � � � �%'& $���CAxI����;7<�����#� �9>�79*�� & �� �� �.(+*,79-3 �C-:(�������+3<YE����� �;5C(+*,7������� �����-�.*��C-43)Y�)6879-:(;7�� ����� �����C-:3<YF7��+O��)*�� � �>�<7������� �8>U3��.7�����"3M/b3���)A?3 �43aIV/ ��.3�<-0>U3�� �4-:-����;78O�<\E(;7�� 9Q � -���:Ag7<��<-0/CY�� & hO�)Ag7#�KO+3�>��9*A�d7#����+59>@(+-:-:/�3H(+*H6��06978I+-�F3M/b3���)A?3o7��+O7����PB��C*HDb3o*�<\E(��4*� � & 7�� ���#�+3 �:O�<*,79I+-�E<AcG & 793��43�I�FG+-47#��)O��� <OK(��d7�� ������7#�KO9�,*.7#������+55�9>$G���9G+-�7��oA?7#�V/vO��:i�<* ��-�z-)6#<-43fp ����<-:(+O���+5 & �45 & sP-)6�)-�O� �>��)*,3�9> & �45 & s¢-�26�<-^* )\E(��4*�<A���-�.3)Y�� & �C3 xB & �v* �>��5� & �C3 x* <\E(��:* )A!��C�,3����-� �gO� ��7#�:-�<Ok3,G����� �>�<7�������+3<Y3H/b3)��<A�O�<3��45���)*,3)Y^3��9>@�PBL79* :�:A?G+-<A���-��)*,3)Y & 79*HOKB�78* �O�26�<-�CG�<*,3)Y`3H/b3�� <A 79OKA!����43)�.*.7<���C*H3<Y_7��+O<3HG�����479-4-0/ (+3�<*,3)Q %'& ��������)G�� �9>UD��<G����+5�3H/b3�� <Ac3k3��4AcG+-� �<7#�������kI��3,(�����)3,3H>@(K-�B & ���)6#<*� & g* )\E(��4*�<A���-�.3�78* %�� & )* ��-�,-:/$���CAcG+-21 {�7835� & 2/h(+3,(;78-4-:/"79*�r�[Q {��=����j795C7#����B�g* ��<79-4-6� & \E(��#� <3k>@*��CA � -4I�<*��kR"���K3������� 5��:6#�� ��� q & 79G�� <*"�CQ�� % *,7#������+5�-=78*,5� �E(+AUI�<*H3 �9>xG���CG+- � �I�n79I+- � � ���CG�eB��/� & ����C*,A��C(+3!���CAcG+-211��P/ �:3v79-:3 � �����v-��:D#)-:/ ����I�k3,(�����<3H3H>@(+-�Q � -� & �C(+5 &� & xA��CI��4-2sJ���bO�JG;79*,79O��459A �9i.)*,3u3 �CA� & �CG�)3E� & 7��E<O+(��<7�������n7��+O,�.*,7#�������+54�d7��nI�X3 �:A?G+-� �>)O_YA?7#�V/g6b(+-���<*.78I��4-����<3����&� & J(��+O�)*,-0/1��+54���K>@*,793��,*,(�� �.(+*�J* )\b(��4* & (+A?7#� ���V6#�C-:6#<A���-�dY�)3,G�����=79-:-:/���-� <*H6#��-������ ��� <A�<*,5#����2/ 3 ��,(;7�� �����+3)Q�];� 3 & �C*��<Y��C(+*aO�����,(+A � & * �C(+5 & �C(�� � & �43j* )G��9*�� � & 7<�� � & <*�x79*�(���!<793H/k7#�K3HB�<*,3 �v79-:3 �?79G+G+-��)38���4� & '� & 79-:-���K5�<3��9>D<O+(��<7�������k7#�+O �.*.7�������+5+Q %'& <*��43(����3.7<���43M>¥7#��� �C*H/n3,(+I+3)���/�.(�� c>��C*JG���9G+-��B & �k79* ����-� <-4-�45���-�J7#�+O 21NG�<* ���-���479-4-0/ �,*.7#���<O�Qg£L(1�� & <* 7�:3l79-43��F����3.7<���43M>¥7#��� �C*H/"3,(KI+3�� ��.(1��j>��C*UG���CGK-�2s ���C-<*,7#�-�U3H/b3)��<Ac3:� & 7<�4�d7#��I�j3,(+*M6��:6879I+-O�)3,G��/�� & (+A?7#� >����4IK-�<3)Q %'& �O�)3 �45#� �9>�3H/b3�� <Ac3k7��+O ����PB��C*HDb3aB��� & 3��,* ��+5���-�a3H(+*H6��:6879I��4-��/�P/* )\E(��4*�<A���-�.3JAU(K3��79-0B�7d/b3J7#�-� �����:G;7�� 2� & A��-���:* U3HG�����,*,(+A �8>6�4AcG+* �CG�<* & (+A?7#��I� & 7d6����C*J7��+O�#� & <*4� & *�d7��,3<Q � ���<O+��-���C-<*.7�����[sJ���9-�<*,7#�-�l3H/b3�� <Ac3%� & 7��%�<7#� 3)���:-4-'3,(K*H6��:6#kB & �� G+* �:Ag78*H/���� & ���:\b(�<3a>��C*v>¥79(+-/�&���C-<*,7#�����7��+O ���CAcG+* �9A!�:3 n*�<3 �:3��.7#�����>¥7#�:- Y �:*,* )3,G��� ���:6# �9>x(���21NG����� <O& (+A?7#��7#�+O�3H/b3)��<A�I� & 7d61��C*<QX£L(��J79I��r6#l79-4-^B�:���<O�G���CG+-xB��� & I���� & O�<G1� & �9>�21NG�<* ������7#�+O�O�)G�� & �9>S(��+O�<*,3)��7#�KO����+5aB & � �d7�� ��+3,(+*�:� & 7��=� & :<3)��79IK-��43 & <O�G+*��������4G+-<3J78* l79O & <* )O$� �� & * �C(+5 & �C(���3M/b3���)A O�26�)-��CG+A���-�S7#�KO�Ag7#��-��7#���<O'� & *��C(+5 & �9(��T3M/N3)��)A �CG�<*.7<�����#�_Y9A?7#���-� ��;7#����9Y7#�+O�(+3�9Q

���� � � � � �#$�� � � � � � � � � � ' ��� !

� ���#���<-:(+O� � & �43k79G+G���+O��01 B��� & /� ��7#���#� & <*�3,(�����������n\b(��#���>@*��CA � -:I�)*��nR6��+3�� ���_YJB & �3 )* ��+O��4G�����9(+3,-0/"3H(+AcAg79*�� � <O � & ?G+* �:Ag79*M/h7#�4A �8> �C(+*2���-����+O�<O )i��C*��,32���eI+* ��+5e3H(+*H6��:6879I��4-��/�P/���#����)G��.3 ���-���lA?7#���K3��.*�d79A �<(+*H* ��<(+-47K�

� ��� ��� �#� � ��� � � � � � � � ��� � � � � � � ��� �$� � � ������� � ��� � � � � � � � � ��� ��� � � � � � � � � ������� � �� � � � ������ � � � ����� �$���, ����� � � � � ����� � ��� � � ��� ���(� � � ��������� � � � � � � � ��� � � � � � ��������� � � ��������� � ��� � � � � � � � � � � � � � ��� � �� ����� ��� � � � � � � � � � ��� �*� ��� � � � ��� � � �$� � � � �������� � ��� � � � � � ��� � � ��� � ����� � � � � � � � � � � � ��� �������� ����� � � ��� ������*��� �� � � � �*� � � � � � � � ��� �

) � *

Page 172: Practical Architectures for Survivable Systems and Networks (Phase

���!����� � ������� ��� � ��� ����� ��� � � ��� ����� ��������� � � ������� ��� � � � � ��� ����� � ���Q� � ��� �"��� � ��� ���M� � � ������ ��� � �M��� ��� � ����� � � � ��� � � � � � ��� � � �� -4I�<*)�jR"���+3)������_Y � � � � � � � � �*��� � � ���� %'& �� & �4-�C3 �CG & ���<79- �H�:I+*.78*H/CYo];���8Q:YWmE2B���9*,D�Y;m �UY �r� �9�NY+G_QS�C�KQ

%'& UB��:3,O��CA �9>fR6��+3�� ��� {�<AUI��bO���)O ����\E(��#�.7�������+3�� & * �C(+5 & �C(��=� & �43F*�<G��C*����F7#�+O 31� & �9G���Ns& 79(�<*"{ �� 3����� ����� �KQ|�V�&<AcG & 783 � � <3jB & 7���3 & �C(+-:O I� � & �O��<G�<*�G+(+*HG��C3� �8>U7#�V/ )O+(��<7�������* )-=7�� ���+5&� �k3H(�� & 77���CA?GK* & ��+3��:6�?3,(+IE§�����x7933,(K*H6��:6879I+-l3H/b3�� <Ac3x7#�KO �� �PB��9*,DE3<Qaq��#����)* ����+531� & �9G��� & 79(�)* ��3X6���2B � & 7��'21NG�<* ������?Ax(+3���A��#���0697<��5� & !)A?GK-��r/bA!��C�(�8>�5����<*,79-�G+* ������:G+-�)3<YB�UAU(+3)�J79-:3 �gD��)G ���eA����KO � & 7��z>��9-4DE3zB & �g3���78*����9(��zB��/� & �#�+-:/ [1KG�<*���������7��+OF���vGK* �������4GK-�<379-:3 �:����+O9� �l5��c793��,*.7d/CQf�F(+*��rB�� & �9-��43)����z6���2B ��� � & 3H(+Ib§��� � �<7#��I�3,(KA?A?79* � � )Oa793'>��C-4-��Bo3)�* % d7�� & ���+54�:3 ���#������9(+5 & ��� & <*��Ax(+3��uI�'[1NG�)* ����-���=78-_-�<79* ����+5+Q* R$1NG�<* ������(�43����#������C(+5 & ��� & )* AU(+3)�zI�5C(��:O����+5�GK* �������4GK-�<3)Q* ��*��������4G+-<3'79*�(���#������C(+5 & ��� & <*�XAx(+3��oI�3 <*����C(K3u(��+O�<*H3��.7#�+O���+5+Q* � �+O�)*,3��.7#�+O���+5'�43"���#������C(+5 & ��� & <*�uAx(+3��f7* d78->���CAcA!�/�.A���-�D� �X*��CI+(+3)����)3,3f7#�+OcO�<G���KONs78I��4-��P/CYN7#�+OaB & 7�� �/�8��79D�<3����c7#� & �)6#'� & <A�Q* % d7�� & ���+5KY1[1KG�<*��������8YKG+*��������4G+-<3<Yb7#�KOv(��+O�)*,3)��7#�+O����+5XAg7d/4���#�fI� ����C(+5 & YbI+(���� & 2/?79* z75#�1�bOa3���78*��dQ %'& 2/kAx(+3��uI�2)AUI�)O+O�)OeO��<G+-0/ ���-���:� & X3M/N3)��)A O�)6�)-��CGKA!��C�zG+*��1��<3,3)Y�7��+OAx(+3��������+3 )\E(���-�.-0/�G�)*,A�d7�� J3H/b3�� <A ����� �;5C(+*,7�������_Y��CG�<*,7�������_YNAg7#��-����+7#����8Y�7#�+Oa(+3�9Q

�0)* & 78G+3 � & �43W*�<G��C*�� ���F���CAUI���;7�� �����aB��� & �#� & <*FA?7���)* �479-43����#� <OF�#�F� & �>��C-4-��B���+5cG;795�Jp>��C* [1+78A?G+-9Y`}�� �9�w�¤p �d7#��G+*���6��:O��7l(K3 )>@(K-^3)��79*)����+5lG+-=7#��9Q

) � �

Page 173: Practical Architectures for Survivable Systems and Networks (Phase

� � � ��� � � � � � � � � � ��� � � � � � ��� �� ����� �� ���� � � � �� ���� � � � � � �

� ��������������4��� �#� ��"!�#�%$&�<�����#�,�('*)��()�+$,�-�.$ ����������� ��/�0���E���1)��($�� !���2�+$ �&3�4)�$�%� ��-�6587-9 �����;:�&$,�#���=<?> � ���A@ �B�����DCFEG3� ��$,�����H���I$ +)�$ +� ��-�J'K!���2L�(#���-�M�0�N$�%� %�($ �M3%���O!��P2�%$Q���M����2����P�R� ��#���('�&3�R'���$,#S�(���B�,#T�.!���2�+$,�B>�����A�,!�$VU��BU0�(<��B����H>(CWEG3�X$ +#O�#������P�!�&3P$ �Y)L�0)�+$,�W�($�A��#T)��($��M���C� �����-�,$ �Z:<�!�� �����P�8���T#!�;2�%������5�('�)P!�<�����[:]\#+>%���P'K$,�(���,$,!�� �&!�$�%� �#��2^2��B����&�(�.��%$�� � �>�%����+�%C_ �a`�bLcedgf;` � �ah jilkmb �on � �qp �Ncrnr`?nrf;sXtvuxw/ymz3x!�$VU��BU0�(<��{�V>;����+#S�O�($ {#��x2�+��+2��0<����,$&�#� �&�B>|�0�!����������� �����P�:�('6� +$QU�����%�S�,!�)�)���$)��%2q<">|���">

�('e�A� ��'�('����#� �L��!�$,����������=�('����(#S)�������C�,�%CY7������� �L��!P$&��� ����� ���^$�%��� ��$ Y��%$QU����%�I�(�W�A$ +�,!��/�(�('���(#S)�������C�6'r������!P$ 5�B�}U���[��+2~�(�W�g\C���P2$�0'X�V���o�.�{�#���(�����#��!��E� � ���P'���$Q#O�<�����#���>���WCREG3�Y)L�0)�+$�()�)P����+�l@ %�(2����.�%�v�G�,3���($ %# t�u(�(�0z ���62L�<�M�(������(����$�%�?�<��%�?� � �M3L�($,�#��� %$ �B��"�&3�*#O�m�1�B#R!�#��&�0'���>���)�������+>�C � ��$F$ ������ �L�(!�$&��� �������(�&�m'���H>R#�/�����0�,3L������%$VU1���+���($ =)�$ +� %$VU�+2O�#�P25�&3L�<�*$ ������ ����!�$&�<�����#�$,!P��%�.#S�/>g<���)�M��� %2��#��2��()�)����+2A�����/�(�B�B>��"����,3^$ %�Q)����� ���}�Q!��)� �,3�6'r�#���%27����#S)�������-�&�%C5��Q>;�)��%# �B�.U��+��%2��0� �:����������� �����7�0' ���(#S)�������C�,������� ����!�$ +2 � �T)P$ ��U���2���Y� ��E�('�!�� +$ ��%$�:U�����%�%C������ �&$ �#�����G#S�#�����m'��($"[�P�(#T)���0�����Y�6�����/�0�Z:��0$ /� ����H����$Q\j�;$ +�"!���$�%���8����$Q\"���M�<�����#�D���&3� �%�(<���#��2��(�Q� �������<��%2 ���-��+$Q'r�#��W2�+U�����%�+���Y�?��� +�e��>7� ���,3���;�C� %$����� � +$QU�����(�N�#��2{� �%�#�DCJ���(#S)�������C�,��($�'���#�.� �B#S)��Z>O3��($,2P�e�($�I2�[U�����+�%�<�!��G'K!������ �����L�0�?����#4<����L�<�����#���8�('�3L�($Q2P�J�0$ I�#��2^� �('@�H�e�($�(CEG�}���,!�2P>I'r�(!���H� ����+$&�#����J�#�P2R$ ������ ����!�$&�<�����#�D����������C� �����2���F'��1�+!�� +2A���5�,3�='r�#� �D�,3L����2��B��%$ ��-�� �&���0'6����#T)��#����-�&� �/�#���Q!�)�)���$�� �&3�I�&�(#�4��%$QU����(C}EG3���D�.�B'*����#!2����#T)�������-�,�}'r�#�����>�&3�[>,�%�#�<��$�%)����#��+2�<?>7���&3�+$,�����{�X2��B��%$���-� ����� �L��!�$,��������DC5�� +$QU�����5�����M3L�0$&�#� ��%$�����%2�<?>7�&3�I������0'*�(�/��%$��L��� �BU�(����� �L��!P$&��� ������� �,3L��� �/�#���,!�)P)���$)� �/�/C=5� +$QU����� ����� �L��!P$&��� �����S�(�,�������P������#S)�������-�&�6���4�Q!�)�)���$��e�I��%$VU1���0C*5���%$QU���� ����� �L�(!�$&��� ���������6�����'K!��B�B>S2� �>��%2�<?>&�,3�I���� �('0����#T)�������-�,�E�/��%#T)�����>;�=�&�H���T2��B��%$���-� ����� ����!�$&�<�����#�����/�#�{!�� (�&3��&�0#!.� ���0'?���(#S)�������C�,�%C.�K5 �![�P�(#T)��� �B�6�,3�-!�� �('.�V�H�4�#�P2~�V }�'� �I�Q!�)�)���$��=7���#S�#�4�;!P#!+$&�(�B��Q�] }���($O�� 8�H��C¢¡58���#�?>����ZU���$� ��#�(�a�^�Q>;��� %# �B�=���£� ��#�O¤[¥§¦(¥�¨ �.3�%$�O�A����'�('=� %$VU�����+�2�B�6<�������^�Q!�)�)���$�� %2� �B#R!��/�M�#�����!��Q�B>©<?> �,3�ª����,�('A�+!�$,$���-�&�Z>���U0�#�B���(<P��F����#S)�������-�&�%C�«��B��%$���-�{�,!�<�����,�F�('5�,3�%�����(#S)�������C�,�G�($������� �L��!�$�%27���R�Q!�)�)���$����&3�8U0�($�����!��=� +$QU�����%� ���g�4�J�/>%�,3L���e$ %�Q)�����,���,3�6�(<������/�H>��$ ��L�(<��B����H>��('��:����#T)�������-�����Y<�W�,3L�($�%2{<?>^#!��$���&3L���9�#��W� %$VU�����0C31+$QU�����%�=�($ -���BU#��O�X¤[¬;­��®�m¦ %®°¯±®°¥�� ��$Q2�%$������P²D����-� +$QU�����E�B�����I#���$ .�Q!�$QU��BU0�(<P�� �&3L���g�#�����&3�+$

�B'G[U�%$V>{� %$VU�����W���� �&3L���.�Q!�)�)���$��,� �&3� �L$Q���}�(�����X�,!�)�)���$)�&���&3�W� ������P2DC

) � �

Page 174: Practical Architectures for Survivable Systems and Networks (Phase

� iFk��ln���b �nrc�n ������f;b�s/iFkof tvuxw��oz5 �©�(�S>#��^!���)P!�<����B�,3�+2©)L�()�%$O!�)N2��������� �,3�F/�0$,���%$Y)L�()�%$��,9 �1�%�(�-7 ������ ����!�$&�<�����#�0����Z:

���%�Q� tvuxw/ymz � ��,� +�B'F!�)j2L�������� tvuxw��mz ¡����J'@�,)x:��(<P��=��� G����� 31�%$���)��.'���$Q#�²3-� �,)D²����m�G�G�WC �+�,��C��Q$ �§C ���(#�� %#!�B��������0)L�0)�+$,���m#!%�(�,!�$�(Cv)��%C��J� �����%��!P2�%����[� ���($,\^�����&3�'���2,�0'D�&3�587-9ª)P$ �m������/C��� `?nrf � ���abLiFc ����� �jcKf"kmb � ���If;k �on°h�`�b ��f1dOf�� �a`�b �on � �qt�uxw(w%zEG3��B�})L�()�%$ ����������2�+$,�8���/�(���(<��2��%$�� � �>�%����4$ +U#�1�%��������F����O)�!P<�����[:H\�+> ���P'K$,�(���,$,!�� �&!�$�(C8�J� ���x:

�&$��x2P!���+�T2�%)����2�+$S�($&�()�3P�%�J� ��[� �%���(�,�:�0'}��$,�()�3��:�,3L���Y�,!P)�)��($�����������-�O�#��2�'r�(!��/�Q:J� ����+$&�#�-�$ [U����/��� ������C � �x2�%�A�(' ��2�+)����2�+$X��$&�()P3��($ g)��($�� �����B)L�#�-�&�'�&3L�<�Y�(��$��%� ��'���$Q�e�($,2�$�+U#�1�%�����������x'���$,#S�������� ���F���&3�+$R)L�($)��������)L���C�,�%C�EG3�A2�%)���P2�%$X��$,�()�3��R�($ S\?:]$ +2�!���2L���C�%��� �F�&3����R$�+U����/�o:��������}�($ I)�$ ��U0�(<��Z>^��!L�($,�#�-���+2F���g<�4$������BU#%2£<?>��0���H�����P'r������+2�)��($�� �����B)L�#�-�&� +U#�� �B'�!�),���O\?: w)L�($)�������)��#�-�&�G3L�/U�W'r�#�B��%2�C*5 )P$ �#� �1�����?���.���ZU���{'���$ �������)�&$,!���������T\?:]$ +2�!���2L���C� 2�+)����2�%$ ��$&�0)�3��%�����,3$�H����2�+� �B$&�(<��Y)�$ ��)�%$)���%�%C � ��$Q���/�G��'�B����?�(2 <L�(���#����+2D�G��� �&3L���2���{)L�($)��������)L���C�'���%2~3���U#�����4#S�#�?>Y2�+)����2�%$Q�%C�31�������2���������������/�0������%2D�-����,3L������=�/U����B2����,3� ���%2O'��($e�#�?>T)L�($)�������)��#�-��� �#S�#���-�M����� �&3�R�(����<L�0�F�)�M��� A�('"�,3�42�+)����2�+$6��$&�()P3DC8EG3�R)��()�+$6�(�B� �O�#�BU�+�6�O��1�%�(���B��%2{)�$��#���������'���$G$�%���,$,!�� �&!�$������4�&3���($&�()�3 �� �,3�(+U#��-���('�)�%$,#S�#����-�G'r�#���B!�$ +�%C�If"k���nKh�`�b ��f{dgf!� �a`�b �on � � ���lf1dgf;s#" � �Fs/n �cKf%$�b��©tvuxw�&oz*!�<�����[:]\#[>A��+$�� � �>�%����+���($ G#S�#�L�(�#%2X<?>Y�=����#4<����L�<�����#�5�('��&3� ��P'���$Q#O�(�"��%<��(' �&$,!P���=�#��2:�&3�!���:�('�� %$VU�+$,��#O�#��-�M�#���%2�<">,��$,���#�����%����������+C'�$���#T)��W�#��2�$�%����(<��I2������,$ �B<�!�������F�('�$�+U#�1�%��������

���#� ����%�������#�%+�,����-�����(�������$�%2����-��'���$=����+!�$ �/�H>!��O��)�!�<����� :H\#[>4���P'K$,�(���,$,!�� �&!�$�(C��e!P$,$ ��-�J� �M3�%#�%�<L�(��%2 ��� ��%$)��� ���/��� S$�+U����/�<�����#� ����)�&�(��� \#+> ��%$QU#%$Q�R�($����L�(2�+�"!L����0CO5E���()P)�$ �?���M3�<L�(��%2 ���2��B���&$���<�!1�����P�-$�+U#�1�%��������5����������%�H���g�Q2�%)���P2�%$Q�,�=���2/�#�M3A��%$)��� ���/��� (�0���/�&32�/�(���/�(2����� '��($Q�e�($,2������������,!P����%�)��+2DC�7 +� /�0$ �M37���������%�Q�&�($V>%� �5���?U#%��� ���?�<�� �($ �M3��/������&!P$&�(�����Q�,!�+�%�P)��($�� ���%!P���($Q�B>X$�%�����(<��B����H>�#��2{$ +�,)�������'� ��#�6�#�L�(�Z>;� ���+Cdgf"bLs � �Fn ��~b �ji ���=k0iFs �Yb��)(* �Fs/ilkob���`�f�n �qb pIi �c�nr`,+�f!�-* �/.]kobLs �/k0iF` �oilkof�tvuxw�00z�;� �,3��$ /�0�D����$Q��2D� ����,!�$,�#����2�B�-!P� %2 ���O#��� ���?�<�� ���L�#�������(�l$ �B�,\%� �%���2��BU��B2�!L�(�B�8���{#O���">^����V:

��������+C"31�B#!�B���($Q�B>������3��(��<����X�Q!�����+��� %2:�&3L�<� ���P�,!�$,�#������/�#�X<�J!���%24���I2����)�&$ �B<�!�� %2R�V>x�)��+#S�+�x����2����)L�($)�����+!����0$%�>���1�(!��,3���-����/��� �����{)�$��1��%2�!�$�%�+�����O#!�/��������������2��ZU1�B2�!L�(�B�%�L$����,\"���&3�+$ 0C EG3��B�})L�0)�+$'K!�$)�&3�+$ [�x)����$ +�D�&3�e!�� 8�0' �����Q!�$&�#����e'���$�)�!�<����� :H\#[>5��%$)��� ���/��� %�*�#�P2A�#�&3�%$�\C���P2�� �('�)�M��� %#���-�&�+C�J�I�(�����A2�%���%$���<�%�I�#� �()�)�����/�<�����#��!�� ����7�&3�$�%�Q3�����2$�%$V>;)������($&�()�3?> ����.3����M3 �����Q!�$ +2 \�+>;�I����!��B2�(�B� �A3L�/U�T�#� �(!P2��� ��$����?U#���BU#%2 ���£�#�?> �&$&�����&�#� ������£!�� ����&�&3�Y\�+>��F�(�B���������P�!�&3������,!P$ %$6<������+$���#�C�,$ ��� ��U#%$ ��&�G����(<������/�H>�Cl�J�-)�$ ��U���2�%�-�Y'��($,#S�(�N>#�� � ��#T)��������Q!�$&������W���(����� �&3L��� �%�#��<�W!�� +29� �2�+2�!���A�,3�Y�(#���!��-���0'6�����Q!�$&�#����Y�(�Q� �������<��%2�����&3��)�M��� %#���-�&�6<��(� +2 ���F�&3�5�����Q!�$&�#����Y�(�Q� �����Z:��� %2X����,3X$ %������+2X���&����+#!��C�,�%C21-� ���P���&3�G��������0�#�/�*�,3����.��3����B�&$,!P����$ +����� �����P�,3��B)��*�#��2:����,!P$&�#�����/���{����$,\!������ �&3�+$ ���Y)�$ ��U���2�'����� �L2������(C

) ��3

Page 175: Practical Architectures for Survivable Systems and Networks (Phase

� � � ��� � � � � � � � � � � � ��� � � � � �� � � � � �� � ��� � � � � �

� ¨ ���m­M¨ ���m¬�����������¥ ¨�¯�¨M¤M¤����m¬{¬����;¨[­&¤[¥§¦������9l���YEG�! (� ¦"� ¨$# ®%�"&EG3' 8#S�)(* %$*+��(�,+.-/(&3'+B�J�()�)� 0-P2'+Z�/+��1+.-'2+��!�23 %2g)�$4+�#S�($*+B�B>R�(�G��-5+B���B!��4(,$&�)(*+.�6-7�('8(,3' }2'+ �$2%!��9(:+. +�;+<- %�=(M�(<P�.+��Q3'+.-P�Y�($*2M3'+9(: !2!(&!P$&�(�a�=(M��-�2��($,2��G'>��$G�V>;�4(: +#S� ��-�2?-' @(H�;��$Q\"�%CA� [U6 %$,�(�3 [���($4(&��3L�/U6 J<� 0 !-R#S�(2' 1(*�})�$4��U�+B2' e�4��#$ =�=(M��-�2��($,2'+B�/�)(*+.�6-�'>��$F�Q>;�4(* %#T�%�6(&33 �L$Q�4(�(,3�$* ! 2�$4+BU6 !-S<?>B(,3' C��$,�?�)-'+��%�)(:+<�6-���!'-P2' %$D(&3' 1�CEANC;«F +)L�($4(,#/ !-�(D�('a«F ['> 0-��4 (��(&3' .'>��!�$=(&3Y$* +�,!��9(:+<-��6'K$*��#�B-'�6-����oU� %$4-�#/ !-�(M�(�8(M�0�,\g��$4��!�)G(&3L��(C+��H [�x)��<+.2!+<(&�Z>/(&�($,�� !(: +21��(-�(2PU"+��4+.-��I(,3' �«F�?«RC

JLK �NMPOFQSRHT1U4V;WXM$QZY[O V U\Y8]D^$_a`,Y�O UbW'QZY�W'cF`,Qd '>�"2%!��e+<-'+<(*+��(�B�B>f�6-�(,3' }5 $,#4>�g��6+<-�(eE� !2M3'-'+<2/�(�N5}$*2M33+<(: !2!(,!�$* Y�hg(E�58¡[�" D %$Q�*+.��- � C �Atji(�mz ��-�25(&33 [�"(* 0-�(H(:���.3'+.2M3�+9(;+B�e$* +�. [U(�)-�(1(:�k(,3' }23 +U6 +�.��)P#/ !-�(G��-�252!�6-3lL��!P$&�)(*+.�6-/�('l�Q>;�4(* %#T�.��-�25-3 !(H�1��$,\"��C+<(,3Y�4(&$4+.-��� 0-�(��,!�$VU�+ZU0�(<'+��<+<(H>I$* +�;!3+�$* +#/ !-�(&�%C*�H$Q$* +�,)� 02!(*+BU� m�('�+<(,�*)[���Q�*+B<��. G<� 0-' @l'(&�n+.-72!�6-��4(,$&��+<-'+.-P��Q>;�=(: %#T�%���1 e2!�6-��*+B2' %$o(&3' Hg(E�5p(:�8<� e�4 %$*+<��!��Q�B>�2' !l'20+. !-�(/�"��-�242'+��42%!��Q��(&3' =$* %�(�*�6-P��(&3' +$* ['>��$�3' +$* (Crq�/sutvsutxw5ybLc�sBy�.{z �e|~}�f"k0s%nuy��L��s9�EG3' �(&3�$4 0 W#S��+.-A�6���(���H�('o(&33 �5 $,#4>Gg��6+.-�(.Eo 02M3'-'+<2/�(�l5 $*2M3'+9(: 02@(&!�$4 g�hg(E�58¡G�($* 6U6 +$Q>A�1��$4(,3?>N²}� w ¡)�$4�oU"+B2' R�Y'>��!'-�2L��(:+.��-{'>��$-�* %�(#T�. %�Q��+<-�(* %$4��)[ +$&�(<3+��.+9(H>A�(#$�6-��S�TU� %$V>��C+B2' I$,��-��6 f�('*�V>x�=(: +#S�!�*� u ¡)�$4�oU"+B2' I�(!'+�2' +�.+<-' %�-��-�2��4(&��-�2L�($Q2�� '>�($ �V>x�=(: +# 2' [U6 +�.��)�#$ 0-�(8��-�2��)2%�"!'+��4+<(*+.�6-�(&3��)(�2%��-�2�$,�(#S�)(Q:+.2%�(���Z>�$* +2�!'2! 520���=(/��23 +U6 +�.��)P#/ !-�(k(:+�#$ (����-�2�l' %��23+.-��G(:+B#/ )����-�2 � � ¡�+<-P�L!' !-'20 /(&3' g23+�$* !2!(*+.�6-x�('20�(#S#$ %$420+��0��(* 02M3'-'�(�.���(>S2' [U6 %�<��)�#$ 0-�(-��-�2{7{�W«S+.-?U6 +�4(&#$ 0-�(C(:�X#S�(\) F+<(G#$��$4 }2'+B$* 02@(&�Z>g�()P)��.+<2/�m:<��< (CgEG3' /+.-�(: !-�(k�('e��!�$W)�$* +�* !-�(I +�[��$4(4�(��2' %�42%$*+B<[ +2P+.-�(&33+���$* %)���$=(f+B�f2!��#T)��. @(: %�Z>�+.- �.+<-' R�C+<(,3(&33���* (&3P$* 0 ��6�?�0���%CEo�k 0-P�?�(�6 {+.-S�I#$ /��-3+.-��('K!P�' +U0�(�B!L�)(:+<�6-$�('�(,3' g(EF54�?�1 }#R!��=(e$4 +'> +$1(:��(&33 }�,)� 02!+<l,2-2' @l,-'+<(*+.�6-P��('o(&3' (,3�$* ! �(H>;)� %�{�('8�,�($*2M33+<(: !2!(,!�$* +�S2' @l,-' +2�(&33 %$* !+.-DC� 5 ¨�� �L®��,¦(¯e�}­:� ®°¥H¨��[¥�¬;­&¨ª�rEF54�{g(EF5 � C � A" 02!(*+.�6- w C w C u C w ¡�+B��(&3' ��Q#$+.-'+B#O�0� �4 !(��('R$Q!��. +����oU� %$4-'+.-���(,3' Y�($,$,��-��6 +#/ !-�(/�8+.-�(* %$&�)2!(:+<�6-D�a�)-�2�+.-�(: +$,2' +)[ !-�2' 0-320 ��0'n(,3' Y)L�($=(&� ��$ +�. %#$ 0-�(,��%�1�8���*�u���*�:���<�:�����b���b� �*�<���v�:�>�.�8�:�<�� Z�b�.��� ��¡@�>�u�b�:�<�8¢£�:�v�h�b�<�����>�v�b���b� �*�<���Z¤ ¥£¦£§£¨)�.�>©=�:�>�<�<�>�e¡=�ª�<�:�8«��. [���6¬���­'®����v�<�:���>�:�;¢b¯q §£§£¦��:�>�>�:���.¢��<�:�<¯°�b�>�,¢£�±�u�*� �=²)³��������b���b� �4�.���"���"�9�* 8�4�.¢£ Z���<���'¢b¯´�:�>�>�±�u�����.�<�:�>���<�����3�b�.�,�b¡*�.¢£���*�<�>� ��¯µ�:�:���b 8�>�\�¶�b�!�.¢��<�:�<·4� ·£�b¡*����� �r�=²

¸*¹!º

Page 176: Practical Architectures for Survivable Systems and Networks (Phase

�.33���* 8)P!�$,)����* m+��D(:�I !-��,!P$* �(,3L�)(G� 20�6-x'>��$,#S��-�(e�V>;�4(: +#��,�)(:+B�4l, +�J�4�Q)[ !20+<l' %2g�4 !(H�('D$* %�"!'+B$* :#$ 0-�(,�%C�EG3' �E�5 +�23 0-�(:+9l, %�H(&33 ��4 %$VU�+<20 +�%�v+.-�(: +$Q'r��2! %�+�j�=(M��-P2L�($,2P�%���-�2G(&33 0+�$G$4 %���)(:+<�6-��,33+�)��+C*�b()P$*��U"+�2' +��(,3' B(: !2M3'-'+.2%�(�*��!'+B2' %�<+.-' +�8'>��$ +�#T)��< %#$ 0-�(M�)(*+.�6-��('=�Q>;�4(* %#T�I!�)��6-£�.3'+.2M3x 0-P�6+.-' ! %$�:+<-��^�,)� 02!+<l,2%�)(:+<�6-��I�($* T<L�(�4 %2D��20��#T#/��-ª<�!3+���23+.-��A<��<��2M\"�I�($* T<�!'+B�<(%���)-�2�)�$4�x2P!'2!(I�.+<-' %���($4 23 +U6 +�.��)� %2�C��� 5m-����L¨[­Q¦(¥r®����j¦(¯��}­:� ®°¥�¨��[¥r¬x­&¨����-5I�)g(E�5 � C � A� !2!(:+<�6- w C w C u C u ¡.�4+B�l�-2' +�*2+$*+�)�(:+.��-g�>�('%(: !-I��$,�()�3x:+<2/�(��¡C�0'n(,3' B��)� %$,�)(:+<�6-L�(�� %�. +#/ !-�(&�%�l�0�,�*+B�6-' +2 (M�(�Q\;�+�F��-�2�+.-P'>�($,#S�)(:+<�6-{�'�o�.�W$4 %�"!'+�$4 %2�CZCBCI�b(23 !l,-' +��(,3' ª(H>x)� ;�0'3+<-P'>��$,#S�)(*+.�6-D�!(&3' �'K$* +�;!3 0-'2[>k�('� [��2M3L�)-��6 (����-�2I�.3��)(Z(M�(�Q\;���($* ��Q!�)�)���$4(* %2<?>5(,3' %�4 f+<-P'>��$Q#O�)(*+.�6-/ [��2M3L��-P�6 %�+C��� 5�����¤[¥�¨@�4¤e�}­:� ®°¥H¨��[¥�¬;­&¨ ��Ax5I��g(E�5 � C � A� 02@(:+<�6- w C w C u C � ¡ +��4�,�W2' %�42%$*+B)3(:+<�6-D��+.-32%��!P2'+.-��W��$,�()�3x:+<2%� t� �($&�()�33+.2/�0�P$* +)�$* +�* !-�(&�)(:+<�6-��+�"+B�*)�$* +�,!�#S�(<��Z>I+<-�(* 0-�23 %2 z ���0'�(,3' .�Q>;�4(* %#T�e�)-�27+.-�(: +$*20��-'-' 02 :(*+.�6-P�XCBCZC1CTEG3' �Ax5 2' !l,-3 %�f(,3' T)�3?>x�4+.2%�(�D20�6-'-3 02!(*+.�6-����<��2%�)(:+<�6-D�a��-P2 +B2' 0-�(:+9l,2/��(:+.��-x�0';(&33 \) +> -'�x23 %�%��20+�$42%!'+9(&�+�[-' @(H�;�($,\"�%��CZCBC8)P���)(Q'>��$,#T�%�� !(*2(CZ�a��-�2��0���.�"2/��(: %�-�Q>;�=(: %# ��-�2�2!��#S)��6-' !-�()� %$V'>��$,#S��-'2! )��($&�(#$ !(* %$Q�%C*�b(e+B�12!�6-��=(&$,!32!(: +25(:�R�,�)(:+B�Q'°> t (&3' z �8)� %$&��(:+.��-L�(�5}$42M3'+<(* 02!(,!�$* })[ +$�=(M��-P2L�($,2P�82' !l'-' %2�+.-�(&3' REo 02M33-'+.2%�(��5 $*2M3'+9(: 02@(&!�$4 (CWEG3' 7A;5 �,3'���.�63'��� #R!��9(:+B)��. W�Q>;�=(: %#T��C+9(&3'+<-T��2'�(#O��+<-7��$e�)-/��)� %$,�)(:+<�6-L�(�P�*20 !-L�($4+.�4�<+.-�\4��-�2/+.-�(: +$*��)� %$,�)(: 0�x�)-�2O#S�/>X2' %�42%$4+�<� m(&33 +<-�(: %$4-L�(��2!�6-��=(&$,!32!(:+<�6-?��$H��)� %$&��(:+.��-��H�('�)L�($4(*+.2+!����($e�Q>;�4(* %#T�m+<-5(&3' fAx5IC��EG3' %�B�.+�)P�* %�H+<-�(&3' +�* ��;!3��(: +212' @l,-'+<(*+.�6-P�-23 0-'��(* f�(!�$H %�<+�#$+.-L�)(*+.�6-/�('�$4 +'> +$* 0-320 %�{(:�7(&3' ��V�e�($�:lL��3�(* %$,�� <� 02/�0!��* (,3' ��420��)� �(' (,3' �g(EF5~+B�/ �P)P�.+.2!+<(,�B> +<-�(* 0-�23 %2L(:�~�()�)��Z>��=(:���0���G�Q>;�=(: %#T�(&3��)(�)�$*�;2�!'2! (�"!��4 (����$ª [��2M3L�)-��6 {+.-P'>��$Q#O��(:+.��-k %�< 02@(&$*��-'+.2%�(���Z>x�X��g(EF5 � C � �"A� !2!(:+<�6- w C w C � ¡[��+.-32%��!P2'+.-���Q>;�=(: %#T�;�0'8��(&33 %$�5}$,#$ %2�A� +$QU"+.2! %�%C��£-$(&3' -�,)'+B$*+9(1�0'�(&$V>"+.-���(:�I!��* {20��#T#$ %$*2!+��(�P�Q>;�4(* %#T�e�.3' %$4 +U� %$)����,�4+�<��< (�6+9( +���U�+9(M�(�"(&3L��( (&3'�(�* G�Q>;�=(: %#T��<[ J�(2' %�"!L��(: G'>��$�2' ['> 0-��4 .)�!�$,)����4 %�*$&��(&3' +$ (&3L��-X$4 %�"!'+B$*+.-P� [�"(* 0-��4+BU6 +�B>G2+!��4(*��#/+B�0 +2��Q)[ !20+��0�Z:H)P!�$,)����* 6�V>;�4(: +#S�+CEG3' F2!�6-'2! %)3(C�('8(,3' �(* 02M3'-'+<2/�(���($*2M33+<(: !2!(,!�$* 8#4!��4(G<� }!3-�2' %$Q�4(*���;2g�C+<(,3'+.-�(,3' F��U6 +$&�(�B�N)P$*��<��< %#�('L23 +U6 +�.��)3+.-�����20��-3lL��!�$4+.-��P����-�2f��)� %$&��(:+.-P�m2!��#S)P�.+��)-�(l�V>;�4(: +#S�l��� )P$*�"20 %�Q��(,3L�)(�+��F<"> -'� #/ %��-����20�"��\"<�����\f(H>x)� ��0'a��2@(:+BU"+9(H>�C �=>7+9(&�4 %�B'���(,3' Fg(EF5a+���#/ +$* +�B>T�W�* !(;�('D�(!'+�2' +�.+<-' %�+���C+<(&3/-'�I�(�,�Q!�$&��-320 �('f20��#T)��< !(: !-' %�Q�G��$^�(2' +�;!���2+>(C @1�)-">L�('f(,3' £$* +�;!3+��*+9(: £�4(&��-�2L�0$,2��{�($4 �-'��(? +U� 0- +�4(&�(<��.+B�,3' +2��$S�,! �$20+< 0-�(&�Z>q�1 %�B�}2' @l,-' %2��})L�($=(:+<2%!����($,�Z>~�C+<(,3 $* %�Q)[ !2!(�(*�~�,!�$VU"+BU0�(<'+B�.+<(H>(�J�* !2%!�$4+<(H>(�}$* +�.+��(<'+��<+<(H>(���-�2�'r�(!��9(B(:���< %$,��-'20 0C � !�$=(&3' +$,#$��$* 0�=33+���3��Z>~�Q!�$QU"+BU0�(<P�. ^�Q>;�4(* %#T��2%��-'-'��(T<� ^#/ +$* %�Z> 20�(#S)����* +2��!3(k�('H �3+B�4(*+.-�� 2!��#T)[�6-3 0-�(&�+�*�(�I-'�)(: %2�+.-��e3��()3(: +$ y �ª(&33 � [��+B�4(:+<-�� 2!��#S)P!3(: +$V:£2!��#T#R!'-'+<2/�)(*+.�6-+.-x'K$&�(�=(&$,!32!(&!P$* %�W�0$* R�=(:+��B�a'K!'-�2L�(#$ 0-�(&�(���Z>{�L���1 %2��C+9(&3�$* +�,)� 02@( (:�5(&33 0+�$}�(<'+B�.+<(H>�(*�^�(2�2�$4 %�Q�6#O��-?>�('�(&33 � %�,�4 0-�(:+��(�6$* +�"!'+�$4 %#$ 0-�(&�+C �;�6-��4 %�"!' 0-�(,�B>�� �(!�$g$* +)[�($4(G+���20�6-��4+�2' +$* +2a(*��<[ £��-X +�,�* !-�(:+��0��(2�23+<(:+<�6-L�(�x�* @(;�('���!'+B2' %�<+.-' +�%�6(: !2M3'-'+B�;!3 %�%����-�2T)�$*+<-'20+B)��. +��'>��$ª(&3' -2' +U� %�<��)�#$ 0-�(J�)-�2S)P$*�"2%!�$4 %#$ 0-�(�('�3'+���3P�B>g�Q!�$QU"+ZU(�0<��. W�Q>;�=(: %#T�%C d �<[ +�.+. [U6 (&3��)({��!�$ �()�)�$4�?��2M3 +B�G�6 0-3 %$&�0���B>520�6-��4+��=(: 0-�(-�C+<(,3�(&33 +.-�(* 0-�({�('��0���[(,3�$* ! f�0'�(,3' (: 02M33-'+.2%�(�§�'�()[ +$&�)(*+.�6-L�0�§�x��-�2{�Q>;�4(* %#T�}�($42M3'+<(* 02@(&!�$4 %�%C

�/sutvs���|��lbLc��ls/nrsIy�.mz �e|~}If"kms/n>y�� ��s<�EG3' W'>�����<���C+.-��I$* 02!��#T#/ !-�2L�)(*+.�6-��.�0$* (M�(\) 0-��(��#$���=(JU6 +$,<L�)(*+�#�'K$4��# �)-� %�($,�<+. %$J�(�,�4 %�,�Q#/ !-�( tvu ��i0z�('�U0�($4+.��!P�F5*EF5� D +$,�4+.�6- y 2�$,�0'%(&�+�0�.$*+9(*(* 0-4<?> � @(: +$ �m +!�#O�)-'-R��-P2 � @(: +$ �;��!'2M33 %$��0'�AP7.�M�����;��#Y:)�!3(* %$FA�20+< 0-'2! R9l�(<DC.EG3'���4 R$* !20��#T#$ 0-�2L��(:+.��-��.�4(:+B���a�4 0 %# (:+B#/ +�B>(���-�2 +<-�#S��-?>^�J�/>;�6��-�(:+<20+B)L�)(: ��!�$�)�$4 %�* !-�(J�4(,!�2P>(C d -3'��)� {(,3L�)(1��!�$���-L�(�Z>;�*+���#S��>R<[ !20��#$ m�(<��*���< !(* }�(�=�I$4 %�Q!��<(n�('a�Q!�<��4 %�"!' 0-�(

¸*¹��

Page 177: Practical Architectures for Survivable Systems and Networks (Phase

+�#T)�$4�oU� %#$ 0-�(&�1(:�I(&33 �g(E�5 (&3L�)(J#/+B��3�(;�"202+!�$J2�!�$4+.-��k��!�$J)�$4�m�4 02@(/C � !�$4(,3' %$;2M3L��-��6 +�e(:�k(,3' �g(EF5�($4 f+<-'2%$4 /�(�4+.-����Z>G %�Q�* 0-�(*+��(���N2' +�,)'+9(: (&3' W'r��2!(m(&3L��(m(,3' %$4 43L�/U6 4<[ ! 0-��(�B#/�(�4({-'��+B#S)P$*��U6 +#/ !-�(,��+<-(&33 kg(EF5 ���()��($4(G'K$4��# +9(&�.$* !-L�(#$+.-��"¡n+.-5(&33 �)��(�4(C(H�1�S>6 %�($,�+C� d 4$4 02!��#S#$ 0-P2�(&3��)(8�4+��6-'+9l,2/�)-�(,�B>^��$4 /�)(* %$ �)(*(* 0-�(:+<�6-�<� 4)L�)+�2�(*�g��2!��#T)��. @(: (�$4 /�(�<+��4(*+.2W�* @(�0' �V>;�4(: +# $* +�;!3+�$* +#/ !-�(&�%�n+.-32%��!P2'+.-�� -'��(}�Q!��=(Y�* 02+!�$*+9(H>��=<�!3(T�(�B�*���,!P$QU"+BU0�(<'+B�.+9(H>��*$* +�.+��(<'+��<+<(H>(�)� %$V'>��$,#S��-'2! (�*�)-�2 ��(&33 %$R2' +�*+B$&�(<��< g�)(4(&$4+�<�!3(* %�+�*��-�2P(,3L�)(I(,3'���* O$* %�"!'+B$* +#/ !-�(,�X<[ S�Q>;�4(* %#X:��(:+.2%�(���Z>�+.-�(* %��$,�)(: +2�+.-�(:�5(,3' B 0-�(:+B$* X�0$*2M3'+9(: 02@(&!�$,�(��2!�6-'2! %)3(%CBA�+B#/+B���($Q�B>��'(,3'���4 X$* %�"!'+B$* +#/ !-�(,�#4!��4(.<� �+.-�(: +��$&�)(* %2G20�(#S)��< !(* %�B>�+.-�(:�T��-?>A$4 %�Q!��<(*+.-��T�($42M3'+<(* 02!(,!�$* +�%C� d *$* !20��#T#$ 0-�2 (&3��)(F�*+���-'+<l,2%��-�(&�Z>}��$4 /�)(* %$l�)(4(: !-�(*+.�6-W<� �)L��+�2F(*�.�6 0-' +$*+<2(�m$* %!P�&�(<��< (�0�(<��=(&$&�)2!(/�¯.�*&(®��,¦(¯F�($42M3'+<(* 02@(&!�$4 %�S��-�2��($*2M3'+9(: !2!(&!P$&�(�G�=(&$,!32!(&!P$* %�7(&3��)($2/��-|<[ ^$4 /�(2'+B�B> +�#T)��. +#/ !-�(: %2 +<-23+B�[ %$* !-�(.)����)(Q'>��$,#T�%��20��#T)��<+���-�(J�C+9(&3�(&3' fg(EF54C� d g$4 020�(#S#$ 0-�2 (&3L�)(4�*+B�6-'+<l'2/��-�(&�Z> ��$* %�)(: +$R�)(4(: 0-�(*+.�6-~<� g)L�)+�2�(*��)�$*��U"+�23+.-����(!'+�2L�)-'20 /�6-33�o��(:�� [�� !2!(*+BU6 +�B>�)�$4��2+!�$* e��-�2423 +U6 +�.��)k20��#T)��.+���-�(l�Q>;�4(* %#T�*��-�2f-' !(H�1��$Q\;��(&3L�)(�2/�)-R2' %#$�6-x:�=(&$,�(<��B>O#/ ! !(C2+$*+<(*+.2%�(�D$* +�"!'+�$4 %#$ 0-�(&�+C� d 4$4 02!��#S#$ 0-P2�(&3��)(}�($* /��(: %$m +�[��$4(}<[ I2' +U���(: +2 (:�/+�2' !-�(*+B'°>"+.-P�S�?�0)���+<-�(&33 k [��+B�4(:+<-��O�=(M��-;:2��($,2��l�)-�2�20��#T#/ +$*2!+��(�0)�$*�;2�!'2@(&�%���C+9(&3 (&3' ��<�6-��0:�(: %$Q# �6�?�(�6�0'�+<-�2�!'2!+.-��JU� 0-�23��$,�Z(:�C %�<+�#$+.-L��(: �($I$4 %2�!'2! 5(&3'�(�* g�?�0)��%C1�*�[��$=(&�k(*�12' +�*+���-��.���6+<2/�(���0$*2M3'+9(: 02@(&!�$4 %�X�)-�2�(:�1)�$*��U"+�2' S)�$&�)2!(:+<2/�(��(!'+�2L�)-'20 8�1��!��B2�<���(&3^3' +��)�(:�Y�Q#/��\) f�(!3(.�*��#$ �('�(&3' W$* +#O�)+.-'+<-��R�?�()P�%C1 �9(:+B#O�)(* %�Z>��N��-?>��Q>;�4(* %# 2' [U6 +�.��)�#$ 0-�(I��-�2x+<(,�F��)� %$,�)(:+<�6-�2' %)� 0-P2��6-����0#/�6-P����(&3' +$F(&3'+<-����&¡� w ¡8(,3' G�/U0��+����(<'+��<+<(H>{�('j��-R��202+!�$&�)(* (�(�' [��+�<��< (�0$* /�0�.+��=(:+<2(�m��-�2I +�,�4 0-�(:+��(���Z>f2!��#T)��. @(: ��* !(��('L'K!'-'2@(:+<�6-L�(�$* +�"!'+�$4 %#$ 0-�(&�+�J� u ¡�(&3' 7 [��+B�4(: !-'20 /�('e�?2!�6-'20 +)3(&!��(���($*2M3'+9(: !2!(&!P$* B(&3L��(f2%��- 2' %#$�6-��=(&$&�0<��B>��,�)(:+B�Q'°>(&33���* �$4 %�"!'+�$4 %#$ 0-�(&�+�X� � ¡O�~2' [U6 %�<��)�#$ 0-�(^)�$4��2! %�,�5(,3L�)(G2%��-L(:���< %$,�)(: 2M3���-��6 +�5(:�P(&33 �$* %�"!'+B$* :#$ 0-�(&�Y��-P2��($*2M3'+9(: !2!(&!P$* A2�!�$4+.-��12' +U� %�.�()�#/ !-�(/�}� y ¡�20��#T)[ @(: !-�(Y)� %$Q�*�6-3-' %�e��-P(&3' �� ��U6 %$4-�#$ 0-�(�*+B2' (�D��-�2|� � ¡-2' [U6 %�<��)�#$ 0-�(W)� %$,�4�6-'-' +���.3'�A)�$4��U�+B2' X�O#$+Z�"(,!�$* f�('��(<'+B�.+<(*+. +�{+<-'2%�B!�2'+<-��O)� %$VU(�0�*+BU� !'-�23 %$,�=(M��-P2'+.-��B�0'�(&3' }$* %�"!'+B$* +#/ !-�(,�%�L�0)�)�$*�()�$*+��)(: C(: !2M3'-'+.2%�(���Q\�+����B�%�;2'+��<+��6 !-'20 0��20�6-��420+< 0-�(:+<��!��*-3 %�,�+�$* +�,)��6-��4+�<'+B�.+<(H>(�"��-�2S�I�6�"�;2T)P$&��2@(:+.2%�(�L�* !-��* $* +�?�($,23+.-���(&3' -2' [U6 %�<��)�#$ 0-�(=)�$*�"20 +�,�%C d +9(&3'�(!3(D(&3'���4 20��-��4(*+<(&!3 0-�(C %�< %#$ 0-�(&�+�3(&3' -3��(:+<�6-��e�('��k(* 02M3'-'+<2/�(�D�($*2M3'+9(: !2!(&!P$* (���R�Q>;�4(* %#T� �0$*2M3'+9(: 02@(&!�$4 (���-P2^��-��)� %$,�)(:+<�6-L�(���($*2M3'+9(: !2!(&!P$* ��($* ��('��.+B#/+9(: +2g#/ +$*+9(/C�F-' ��(' (&3' £<'+B���6 +�4({)�$*�(<��. +#S�5+<- (&3' £)L�(�=({3L�(�^<[ ! 0-X(&3L��(�(&3' �+.-3+<(:+��(�-$* %�"!'+B$* +#/ !-�(,�{�1 %$4 +�#T)�$4��)[ +$,�Z>T��-�2�+.-320��#T)��. @(: +�B>Y�4(&�)(: +2^��-�25(,3L�)(;(,3' +�[ 02@(&�H�('l�Q!�<��4 %�"!' 0-�(m2M3L��-��� %�H20�(!���25-3��(G<� )�$4��)[ +$,�Z>g#S��-L�(�6 +2DC*EG3'+B�-)P$*��<��< %# #R!��4(-<� ��(2' %�"!L��(: %�Z>^�(2�2P$* %�Q�* +2 +.-�(,3' 6U6 %$V>G-' /�0$.'K!�(&!�$4 (CEG3' $g(EF5  D %$Q�*+.��- � C � 23 !l,-'+9(:+<�6- �('=�g�Q>;�=(: %#T�W�($42M3'+<(* 02!(,!�$* X�Q!����6 +�4(,��(,3L�)(W�g�V>;�4(: +#S���($42M3'+Z:(: !2!(,!�$* F+B�e��)�3?>;�*+.2%�(��+�#T)��. +#/ !-�(&�)(:+<�6-DCFEG3L�)(;+��n+.-T�6 0-' +$&�(�N�IU� %$Q>S!'-��4��!'-�2O)�$&��2@(:+<20 (C*5��Q>;�=(: %#T��($42M3'+<(* 02!(,!�$* {�,33��!���2 -' +U� %$5 ��+��4(/�6-��Z>��(�S�ª)�3?>;�*+<2/�(�C+B#S)��< %#$ 0-�(M��(:+.��-D����-�2 +B�Y#/���=(T2' %�4+�$&�0<��B>)�$4 020 +2' %2£<?>��/20�6-'2! %)3(,!L�(�J¯.�*&(®��,¦(¯��($*2M3'+9(: !2!(&!P$* (C�@?��$* R�Q)[ !20+9l,2/�(�B�B>(���g)�3?>;�*+<2/�(��+�#T)��. +#/ !-�(M�)(*+.�6-$* +)�$* +�* !-�(,�X�A�Q>;�4(* %# <�!'+B��2D�Z-'�)(���-��0$*2M3'+9(: 02@(&!�$4 (CSEG3L�)(�2' !l'-'+<(*+.�6-£U"+.�����)(: +�6<L�(�*+<2X)�$*+<-'20+B)��. +� �('�6 !-' %$,�(�.+9(H>��?�(<P�4(&$,��2!(*+.�6-�����-�2X$4 %!��,�(<'+B�.+<(H>(�?��-�2X)P!3(&��(,3' H2/�0$4(*<� +'>��$4 ;(&33 J3'��$Q�* (C d 3L�)(ª+B� -' 0 +2' %27+B��f(,$,!' �Q>;�4(* %#T�G�($*2M33+<(: !2!(,!�$* 0�3-L�(#$ %�Z>��x�I�<���6+.2%�(�L$* %�(�.+B�/�)(*+.�6-7�('8(,3' 'K!3-'2!(*+.�6-L�0�j$4 %�"!'+B$* %#$ 0-�(,�;(&3L��(2/�)-{<� 8$4 /�(2'+B�B>/20�6-?U� %$4(* %2?+.-�(:�Y�R)P3">;�4+.2/�0��+�#T)��. +#/ !-�(M�)(*+.�6-D�"<�!�(H(&3L�)(J2'�� +�H-'��(H��U� %$,�Z>52!�6-��4(,$&��+<-(&33 -)P3">;�4+.2/�0��+B#S)P�. %#$ 0-�(&�)(:+<�6-DClEG3' %$4 m+B���(�B�e�/>;�e�6�* +$*+<��!���2L��-��� %$D�('�(,$Q>"+.-P��(*�W!��* -�*�('%(H�e�($4 �4����!x:(:+<�6-��e�.33 %$* 63��($,2P�e�($4 +B�e %�Q�* !-�(*+��(���3��$;�('F!��*+<-��B+.-L�0)�)�$*�()�$*+��)(: 3L�($,2x�J�($4 8�.3' %$4 W�*+�#T)��< }�*�0'%(H�J�($4

¸*¹��

Page 178: Practical Architectures for Survivable Systems and Networks (Phase

�()�)P$*�?��2M33 %���1��!���24�,! �$20 0C*5q�<���6+.2%�(�;�($*2M33+<(: !2!(,!�$* J#4!��4(ª-3��(�<� J�.�"2M\� +2I+.-�(*�F+�$Q$* +U���2%�(<��< e2' !20+��4+.�6-P�(&3��)(-�Y'> [� >� /�($Q� ���)(: +$J<[ !20��#$ (:��(&�(���Z>$��<��*�(�. !(* (C�8)[ !-©�($42M3'+<(* 02@(&!�$4 %�A�($4 � +�,�4 0-�(:+��(�§C d 1�4(,$*�6-P���B>�$4 020�(#S#$ 0-�2�$* !20���6-3+<(:+<�6- �('F(,3' -' ! %2q'>�($�.�(�6+.2%�(�J�($42M3'+<(* 02@(&!�$4 %��+<-|�.33+.2M3 (,3' %$4 �+B�720�6-��4+�2' +$&�(<P�. G %#T)�3L�(�4+��$�6-|�* %$VU6 +$,�£�> (Cv��CB�nlL�. {�* +$QU� %$,�+�-' @(H�;��$Q\��4 %$QU� %$Q�%�=��-�2��(!3(,3' 0-�(*+.2/��(:+.��-~�* +$QU6 +$,�&¡Y�)-�2 +.-��.33+.2M3P(&$Q!��4(H�1��$=(&3'+<-' %�Q�B2/��-�<� O'>�"2%!��4 %2�.3' +$* B+<(�+�� #/���=(F-' ! %2' +2£$&�)(,3' %$�(,3L��-�2'+B�4(,$*+�<P!3(: +2�<�$*���(2��B>(CY��A" 0 tvu��!&oz ��-�2 t �Pw��oz '>��$m [�P�(#T)��. +��('-3'��� (,3'+��k2/��-�<� {23�6-' (Cª5}�B�*�����* ! t�u0y6imz '>��$Y��23+��*2+!��,�4+.�6- �('-�.3L�)(B(,$,!��=(H�;�($4(&33+.-' +�,�$2/��-�<� ��2!20��#T)��.+B�,3' +2�+Z'8(&3' m2%$Q>;)3(*����$,�()�3?>5+B�;+�#T)��< %#$ 0-�(: +2�+.-S�*�('%(H�e�($4 +.-��=(: /�025�('l3L�($Q2P�e�($* 0�L��-�2g�4��#$ �('o(&3' W)'+9(,'r�(�B���1�('�(,$Q>"+.-P�7(*�Y$* %�Z>��6-G+.-��(2' %�"!L��(: %�Z>5(&$Q!��4(H�1��$=(&3?>G+.-P'K$,�(�4(,$,!'2@(&!�$4 (C¢¡�m�)(g�,! �/2!+. !-�(,�B> +U"+�2' !-�(�+.- (,3' ��,!3+<(: ��('�(&3�$4 0 (H>;)� %���('1�,�0$*2M3'+9(: 02@(&!�$4 %�Q� +��/(,3' �-'��(*+.�6- �('���6 !-' %$4+.20�-�V>;�4(: +#Y:b+�#T)��. +#/ !-�(M�)(*+.�6-x:b+.-�23 %)� 0-�2' !-�(/�J$4 %!��,�(<��. 0�-�(<��4(,$&��2@(/�-�($42M3'+<(* 02!(,!�$&�0�}�4(,$,!'2@(&!�$4 (&3��)(B20�(!���2�<� �+�#T)��. +#/ !-�(: %2��6-�2'+B�[ %$4 0-�(Y)����)(,'>��$Q#S� (:���,�)(:+B�Q'°>ª)[���Q�*+B<��B>ª$* +���)(* %2�<�!3(Y23+B�[ %$* !-�($* +�"!'+�$4 %#$ 0-�(&�+���C+<(,3'��!3(I)�$* +#O��(&!�$4 %�B> 20�6-��=(&$,��+.-'+<-��{2' %�4+��6-~23 020+B�*+<�6-��%CA5 �<(,3'��!���3 +.- �*��#$ T�* 0-P�* ��-G+.-�(* 0-�({�('�(,3' g(EF5��0)�)�$*����2M3D�,+<(e+��H-'��(.�Q! �$20+< 0-�(&�Z>g�; +���a#$��(:+ZU0�)(: +2O�C+<(,3'+.-5(,3' 6'K$&�(#$ +�1��$,\/�('(&33 �(,3�$* ! fg(E�5 �,�($42M3'+<(* 02@(&!�$4 %�,�PC

�/sutvs � z �e|G��s9� � f;`��onuy������ *0�/.byk���b�on>y�� � f;`?ilkmn����e3L�()�(: %$ � �(' (,3' g(E�5  D %$,�4+.�6- � C � +��T���($Q�6 %�Z>P(&33 1�&�0#/ ?2M3L�()3(* %$�(,3L�)(T�J�0�O$&��(&3' +$O<� %����(: %2P�B>+.-320��$Q)[��$,�)(: +2�+.-�(:��(&33 T5*EF5  D %$Q�*+.��- y (:���(2�2P$* %�Q�f+<-P'>��$Q#O�)(*+.�6-��* !2%!�$4+<(H>�����-�2x+��6$4 %���)(:+ZU6 %�Z>�!'-;:2M3L��-P�6 %2Y2' +�,)'+9(: e(&33 J)L�(�Q�&�(�6 H�0',(H�;�6>6 %�($,�� �(�<(,3'��!��(3R$* ['> %$* !-'20 +��3L�/U6 G<� 0 0-T�(2P2' %2B(:�m(&3' G#$��$* $* !20 !-�(8«F�?« ���?�0�ZA� 02+!�$*+9(H>^5}$42M3'+<(* 02!(,!�$* O��« � Ax58¡H+<-�(: 0-P2' %2{'>��$G!��* ��C+<(,3{'K!3(,!�$* W�V>x�=(: +#S�+CW��A� ! A� !2!(:+<�6-��}C u '>��$e2'+��42%!��Q�*+.��-?�0'�(,3' W« �fA;54C¢¡ 1m-P'>�($4(&!3-L�)(: +�B>(�3(&3' g(EF5�3L�(�C-'�)(G<[ ! 0-{!�)���$,�(2' +2G(*��(2' +�"!L�)(: +�B>S�(2�2P$* %�Q�e+<(,�D /�($Q�.+. +$�2' !l,2!+. !-'20+< %�%�P��-�2A�0��#$���4(D2!��#S)P�. !(* %�Z>7+��6-'�($* %���Q!�$QU"+BU0�(<3+��.+9(H>B+��Q�,!' +���-�2I�,!�$VU"+BU0�(<'+B�.+<(H>?:]$* %���)(: +26$* +�;!3+�$* +#/ !-�(&�o��(&3' +$o(,3L��-��* !2%!�$4+<(H>�C�EG3'+��l�* ! %#T���4 %$*+<��!��Q�B>6�Q3'��$4(,�*+B��3�(: %2�CEG3' G'>���B�.���C+.-���20��#T#/ !-�(&���($* H +�,�4 0-�(:+��(���Z>I(&3' .�,�(#/ .�0�D(,3'���4 -$4 %�6+B�4(* %$* +2/+<-/g���-"!L�($Q> w i6i � �C+<(,3$* +�,)� 02@(�(:�$(&3' I2�$&�m'%(&�{�('*5*EF5  D +$,�*+<�6- y CG�b(6�()�)� /�0$,�C(&3L�)(m�6-��Z>{�T'> [� �(' ��!P$m %�($,�<+. %$C2!��#S#$ 0-�(,��1 %$* g��2!(,!L�(���Z> �(2�2�$4 %�Q�* %2��=�)-�2�(&3"!��f(&3' g$4 %�< +U0��-�(I2!��#S#$ 0-�(,�I'K$*�(# t�u �)i0z �0$* O$4 %)� /�)(* %2�3' +$* !�)j2L�)(* %2G(:�7 0-'2!��#T)L�(�,�-�,!P$QU"+BU0�(<'+B�.+9(H>/+B�,�Q!' %�+C@�!'2M3���$4 /�)(* %$X��!3+�2L��-320 5�6-�33�o� (:��+<-�(: %$Q)�$* @(B(&3' +�* ^�4(&��-�2L�0$,2��Y��-P2�)�$*��(*��2!�����k-' 0 +2��B(:��<� +.-32%��!P2' %2DCnA;!'2M31��!3+�2L��-320 +��.�0<��*���B!3(: +�B>� %�,�4 0-�(:+��(�8(:�Y#S�(\�+.-��I(,3' fg(E�5 �()�)P$*�?��2M3{)�$,��2!(*+.2/�0�§C�b(m+��}�=(:+B���8-'��(�2%�< /�($ 3'�����,!�$VU�+ZU0�(<'+��<+<(H>A)����<+.2+>(�,(&3�$4 /�)(,�%�NU;!��<-' %$,�(<'+B�.+<(*+. +�%���-�2���202! %)3(&�(<��. 4$*+��Q\"��($4 �+.-�(* 0-�2' +2P(:�?l'(B+.-�(*��(&33 /(&3P$* 0 ��,�($*2M33+<(: !2!(,!�$* +�,��C �$4 %�Q!�#O�0<��B>x(&3' [>~�0$* O<� +>��6-�2P(,3' O�420��)� �('C(&33 ?g(E�5I����-�2�#R!��=(Y<[ ^�02�2�$* +�,�4 %2 +<-P(&3' ��()[ +$&�)(*+.�6-L�0�e��-P2|�V>;�4(: +#S�T�($42M3'+<(* 02@(&!�$4 %�%C �e!3(7+<(�* ! %#T�m(*�S<� f+B#S)����Q�*+�<P�. 8'>��$H(&33 Ig(EF5 (*�S'K!��9lL����+<(&�C+<-�(* 0-�23 %2�)�!P$,)����* I!'-��. +�,�C(&3'�(�* k2!�6-'2! %)3(,�8�($4 [�x)��<+.2!+<(&�Z>X��2!20��!3-�(* %2T'>��$%C�EG33 )�$4��2! %�Q�;�('� %�4(&�(<��<+��,33+.-�����-�2S��2!20��#T#/�;2L�)(*+.-��F(,3' .)[�(�.+.2[>��6(,3�$* %�)(&�+�U;!��.-3 %$&�0<'+��<+<(:+< %�+�P��-P21��2!20 +)3(M�(<P�. W$*+B�,\"�.#R!��4(.�4��#$ %3'��� <� W#O�02' [�x)��<+.20+9(/CA���#$ {�(2�2'+9(:+<�6-L�(�=)[�6+<-�(: %$Q�B(:� $* %�< +U0��-�(S�4(M�)-�2L�($Q2��O�)-�2q��!3+�2' +�.+.-3 %�Y�($4 ?-3 +U6 +$4(,3' %�< %�,��-' 0 +2' %23' +$* (C � ��$C ���0#S)��< (�j�S$4 +'> +$* 0-320 f(*���}�HA���:HE �}: ��� & �+�Q5 �6!'+B2' (:��1{-�2' +$,�4(&��-�2'+<-��g«F +�*+B�6-1«F�"2[:!�#$ 0-�(M��(:+.��- +<-�EF$,!��=(: +2aA;>;�4(: +#S�+���� D %$Q�*+<�6-x: w � u � 2@(:��<� %$ w i 0�0 �;��$S��-?>|�,!'2!20 +�,�*�($M¡S#$+���3�(T<� !��4 +'K!��D'>��$G)����<+.2+>(C��HA���:\AxE.« : ���(� : 0!� �+� �6!'+�2L�)-'20 }'>�($G5})�)��Z>"+.-��B(&33 6E�$Q!��4(* %2��;�(#S)�!�(: %${A">x�=(: +#��U0�(��!L��(:+.��-g�e$4+<(: +$*+�� +<-5Ax)� 02!+<l,2}�ª-"U"+B$*�6-�#$ 0-�(,�,� (&3' ��n %�B�.��� �;�"��\x¡*)�$*��U"+�2' +�J!��4 +'K!��j��!'+B2L��-'2! '>��$ �()�)��Z>"+.-��$(&3' �}�HA�� �* !2%!�$4+<(H>�2%$*+9(: +$*+��x�N�0�}2'�" %�85}7 � 0�� : w i �5})�)� 0-P2'+Z� �}C �$4��2! %2�!P$&�(���N)� %$�:�*��-'-' %���*��-�2�)�3?>x�4+.2%�(�=�4 02+!�$*+9(H>~�($4 g�(�B�*��20�6-��4+�2' +$* +2 +.-�5}7 � 0�� : w i C� m���1 +U6 +$%��587 � 0�� : w i +��I�

¸ 3��

Page 179: Practical Architectures for Survivable Systems and Networks (Phase

<L�($4 [:]<[�6-3 %��#/+<-'+�#4!�#��0��-�2$+<(,�* +�B'�+�� (*���W3'+B2' %<���!'-�2Y<?>I(,3' .E-�HAP���}C � ��$ �P�(#S)P�. (��(,3' G)L�(�Q�Q�1��$,2)����.+<2+>7+��=�*��#$ +�.33 %$* ���!3(H�('�(&3' 82��($,\S�(�6 +�%���)-�2A$* [�, 02@(&�H-'�6-3 ��('8(,3' 8$*+B�,\"�e�('l)��(�,�V�;��$Q2��G)L�(�Q�*+<-����U6 +$���-X!'-' !-'2%$V>x)�(: %2$-' @(H�;��$Q\I��$ �)(&3' +$Q�C+��4 eU;!��.-3 %$&�0<��. ;(*�F2/�0)3(&!�$4 (��+B$,$* +�,)� 02@(:+BU� H�('3'���p(&3' [>X�($4 2%$4 /�)(* %2DCR7{ +�. +U0��-�(�� �W@ Ax�=��)[�(�.+.2[>1�=(M��-P2L�($,2P�8�;��!P��2 �(���4�A<[ 4$* %�< +U0��-�(W3' +$* (CR7{+B�,\{�4(M�)-�2L�($Q2���($4 �#$ 0-�(*+.�6-' +2G�6-��B>�+.-^)L�(�Q�*+<-�����<�!�( �Q3'��!��B2�<� 6$* ['> %$4 0-'2! %2 �P)P�.+.2!+<(,�B>�C�£- g(E�5 � C � A� 02@(:+<�6- � C u C w C w �'(&3' �8$&��-P�6 �;���(\£� ��u0��� C u�0 :=A;E.«W¡;+��.#O�)-�2L�)(* %2DC8�r�b(m+��C-'��({ +U� 0-(&33 X<[ +�4(�(&3'+<-��^�/U0��+����(<��. 0��<�!�(��)(W�. %�(�4(W�4��#/ B�0'1+9(&�6�4 %$*+<��!��8��/�.����-�2 �,33��$4(*20��#$+.-��(�8�,3'�(!���2£<� $* !20����-'+��! %2DC¢¡��b(8�1��!��B2��* ! %# (:�g<� R�()P)�$*��)P$*+���(: �(:�g#$ 0-�(:+<�6-�(,3' �n +���.��� �1����\ª���HA���:=AxE.« : ����� :0!� ��-'��(* %2��0<[��U6 /¡}��-�2��)(8�< /�(�=(8��2M\�-'���.�< %2��6 k+<(&� �.+B#/+9(M�)(*+.�6-��e�(� �1 %�B�§C 1m-P'>�($4(&!3-L�)(: +�B>(��(,3'+��m+�� ��- [�P�(#T)��< 5�('.�.3?>�(&33 A#/ +$* A#$ 0-�(:+<�6-P�('-�,!32M3�$4 +'> %$4 0-'2! %�7+��k+.-L�(23 %�"!L�)(* �; ^�0$* 5-'�)(Y2' /�(�<+.-���C+<(,3��$20�"��\"<[�"��\A)�$4��2! %�,�+C 5 ���4���L�.3L�)(6�0<[��!�( �}�HA���:HE �}: ����i �§�;�(#S)�!�(: %$�A� !2%!�$4+<(H> Ax!�<��V>;�4(: +#�£-�(: +$,)�$4 !(M��(:+.��-¡�� d 3L��(��(<[�(!3(�(&3' S�;��#T#/��- �e$*+<(* %$4+��A�(����-x %#$ %$Q�6+.-��A�=(M��-P2L�($,2��F�.3'+<2M3 �.33 0-+.-P�4(M�)-�(*+��)(* %2^�C+<(,31�)(-�< /�(�=( �6$,��-��6 : �;�"��\�:£ +�"!'+BU0�(�< 0-�(.$* +�;!3+�$* +#/ !-�(&�}$4 %)�$4 %�4 0-�(&�}�T�4+��6-'+9l,2/�)-�({+B#Y:)�$4�oU� %#$ 0-�( t �(�9(&3'�(!���3�+<(.�=(:+B�����< /�/U6 +� #4!'2M3�$4���(# '>��$H+<-'20��#T)��< !(: +�B>S�,)� 02!+<l, +2�2+$*+<(* %$4+�� z ��£-�g(E�5 � C � A� !2!(*+.�6- � C u C u C w ��(&3' � ��$4(* %�+�/�X#O��(: %$4+��(�N�,3'�(!���2^<� �$4 +U"+��4+<(* %2DC�£- g(EF5 � C � A� !2!(:+<�6- � C � C w C � ���6+BU� 0-�(,3' 52!�6-�(&$*��U� %$,�V>|��-�2P2!�6-P'K!��4+.�6-�$4 %���)(:+<-��?(*� (&3' OE�$Q!��4(* %2�m @(H�;�($,\��£-�(* %$Q)�$* @(M�)(*+.�6-D��+<(�+��o-'��( 2+�. %�($F�.3��)( +B��#S��-�2L�)(* %2DCF�£-X�(2P2'+<(*+.�6-D�´(&33 eE � �l�£-�(: +$,)�$4 !(&�)(:+<�6-2'�"2%!�#$ 0-�(4� �}�HA���:HE �}: �xw�w ¡e�,33��!���2^<� W#/ !-�(*+.�6-3 %2DC5}�9(&3'�(!���3G+<(-3L�(�-<� 0 0-�+�#T)�$*��U� %2��T�<+<(*(,�. 8�4+.-'2! (,3' W D %$,�4+.�6- y C �{2�$&�m'%(&�%�E��(<��< � : w � *$*��(*��2!�������-�2�A� 02+!�$*+9(H>5A�(M��-�2��($,2��&¡n2!��!���2S�4(*+����L<� 02!��#$ }��#R!'2M3g#$��$* -!��4 +'K!���(M�(<��< (C�EG3' 8�. ['%(Q:]3L��-�2$20���B!�#$-�4(*+��B�}�(#$��$Q)�3'��!��Q�B>|��!P#S)��/(:���6 @(&3' +$A�()�)P�.+.2%�)(:+<�6-D�G)�$4 %�4 0-�(M�)(*+.�6-��}��-P2��4 %�Q�*+.��-����/>6 %$Q�%�C(&$,��-��,)���$=(��-�2 -' !(H�1��$,\|���/>� %$,�+�-��-�2L+<-©�ª�4 02!�6-�2 ��$4��!�)'+<-���2L��(M�(�<+.-�\��)-�2©)�3?>;�*+<2/�(�-���/>6 +$,�+C EG3' �#$+�2P2��. 20�(��!�#$-I�<+��=(&�F�-'> [��$&�)(,3' %$��6 0-' +$*+<2=)�$4��(:�"20�(���%CFEG3' =$*+��(3�(V:H3L�)-�2f2!����!P#/-��.+B�4(&�F$&��(&3' +$�3L�0)�3L�(�%�($,2��Z>��20�(���. !2!(*+.�6-f�('j�* 02+!�$*+9(H>?:H$* +���)(* %2X�=(M��-�2��($,2�����-P2X)�$*��(*��2!�����+�(�C+<(,3I-'�W$* +���)(*+.�6- (:�F(,3' G#/+B2�2��< 12!����!�#$-D��.3' @(&3' +$n(,3' .�4(M�)-�2L�($Q2�����-�2Y)�$*�)(:�"20���B���($* .��2@(&!L�0���B>4�(2' +�"!L�)(: .'>��$���-?>B+<-�(: 0-P2' %2T)�!�$Q)[���4 %�}����-P2$+Z'�*�P��.33+.2M3¡ ����-P2 -'�$+.-�23+.2/��(:+.��-��('��.3' @(&3' +$8��-?>^#$ /��-'+<-��('K!��B�B>S�* !2%!�$4 k+�#T)��< %#$ 0-�(M�)(*+.�6-P�G��2!(,!L�(�B�B> [��+B�4(/C©� � ��$R#S��-?> �('C(&3' +�* (�D(&33 � [��+��=(:+.-P��)�$*��(*��2!�����R��-�2 (&3' !+�$I+B#S)P�. %#$ 0-�(&�)(:+<�6-��I�($* g�4 %$4+.��!��Q�B>��/�1 %2DC¢¡�b(G�1��!���2{<� 6!��* ['K!��8(:�Y3L�/U6 I�X�* %)��($&�)(* (M�(<��< T�r!�)j2L�)(* %2{$* +��!����0$,�B>P¡=)P$*��U"+�2'+<-��Y�*��#$ 6��!'+B2L��-'2! �(�H(:�B(,3' W�4(M��(: ��('o(&3' ��($=(/�L��-P2� !-;!P#/ +$&�)(*+.-��B2+!�$,$4 0-�(��($.��-�(:+.2!+�)L��(: %2G+B#S)��< %#$ 0-�(M��(:+.��-��1(,3L�)(-�($4 $* +�. [U(�)-�(%C�EG3'+B�D(&�(<��< -23�� +�1-'�)(=�4 0 +# (:�W'r�(���'-��)(&!�$,�(���Z>I+<-�(*�4�)-">I�('�(,3' {(,3�$* ! g�Q�($*2M3'+9(: !2!(&!P$* %�Q����(:�"��,)� 02!+<l,2X'>��$ (,3' /g(E�5I��(:�"�{�� 0-' +$&�(��'>��$F(,3' Y�Q>;�4(* %#T�4�0$*2M3'+9(: 02@(&!�$4 (����-�2x-'��(I�()�)P$*��)�$4+��)(* 4'>��$ (&33 ��)� %$,�)(:+<�6-L�(�a�0$*2M3'+9(: 02@(&!�$4 (CJEG33 k-' ! %2�'>�(${+9(-�,!����� %�4(,�8�7-' +� 2+���(�Q�C�('W�,�0$*2M3'+9(: 02@(&!�$4 %�S2'��2+!�#$ 0-�(&�+�)� %$,3��()����4��#$ +�.3L�)(��(\�+.- (:�{(&3' 4�4+.-�(* %$,)P$* !(&�)(:+<�6-��-2'�"2%!�#$ 0-�(&�F�C+<(,3'+.-�(&3' �E-�HAP���~$&��+<-"<[�����4 %$*+< %�+��,!32M3��(� (,3' OE-�HAx�=� tvu(���oz ��E � � tvu(�Pw+z ���)-�2�E.«8� tvu(�?u�z �)-�2 (,3' �2!��$,$4 %�,)��6-�23+.-���+.-�(: +$,)�$4 !(M��(:+.��-2'�"2%!�#$ 0-�(,�T'>��$7(&33 �E-�HAP��� tvu(�(y(z ��-P2�E �-� t�u(�(�mz CXAx!'2M3 �)- +.-�(* %$,)P$* !(&�)(:+<�6-�2'�"2%!�#$ 0-�(/20��!��B2�(�B�*� +.-32%��!P2' ���!'+B2L��-'2! ��6- 3'��� (*���6�~'K$*�(# $* +�"!'+�$4 %#$ 0-�(&�ª�%�=��)[ +$&�)(*+.�6-��(�}�0$*2M3'+9(: 02@(&!�$4 %�"¡/(*����6 !-' %$4+.2g�0$*2M3'+9(: 02@(&!�$4 �(:��(&3' g�V>;�4(: +#S�Y�0$*2M3'+9(: 02@(&!�$4 (�ª2!��#S)P�.+��)-�(W�C+9(&3�(,3' Gg(EF54���)-�2~#$+���3�(4�(���4�+.-32%��!P2' X�*��#$ Y��!'+B2' %�<+.-' +� �6-ª�V>;�4(: +# ��-�2 �*�('%(H�e�($* $ 0-P�6+.-' ! %$4+.-���CT5 ��!'+B2L��-'2! T23��2+!�#/ !-�(��1��!��B2<� �"(&$* +#/ +�B>gU0�(�B!L�(<��< (�;�.3' !(,3' %${+<(H+B�.�T)��($4(C�('o(&33 kg(EF5�2'�"2%!�#$ 0-�({��$H��(,3' %$V�C+��* 0Cg(EF5 � C � A� !2!(:+<�6- � C y +B� �=(:+��B�aU6 %$V>1�1 /�(\?+.-�20��#T)L�($4+��4�6-��C+9(&3 (,3' R$* +�4(��('ª(&3' 42'��2+!�#$ 0-�(/C EG3' 'r��2@(F(&3L��( -'�A�4(&��-�2L�0$,2��W�($4 R>6 @(W#O��-P2L�)(: +2�+��m-'��(� 0-320��!�$,�(�6+<-��O'>��$�(,3'���4 X$* %�Z>"+.-��g�4���. +�B>?�6-�(&33 g(EF5�'>�($e(&3' !+�$G!'-�23 %$,�=(M��-P2'+.-��$�('�3'���S(:�Y)�$4��2! 0 +2DCg(EF5 � C � A� 02@(:+<�6- � C � +����0���*�8�1 /�0\jC � �($ [�P�(#T)��. 0��#R!'2M3X�($* /��(: %$*�(!'+�2L�)-'20 e+B��-' !20 +�,�&�0$Q>Y$* +���)(*+.-��

¸ 3´¸

Page 180: Practical Architectures for Survivable Systems and Networks (Phase

(:�/(&3' I�* 02+!�$*+9(H>���2!��#T)��. �3+9(H>��N��-�2�!P�* +'K!P�.-' +�,� �('*!P�* %$�+.-�(: +$Q'r��2! %�%C}�£-��6 0-3 %$&�0�§�j�*��)�33+��4(*+.2%�)(: +2�!��* +$+.-�(* %$Q'r�)20 %�I�($4 TU� %$Q> 20�(#S)��< [�N�l2'+ �$2+!��<(�(:��!��* 0����-P2ª'K!��B�ª�('G�* !2%!�$4+<(H>���/�.�+C{EG33+�� 0-�(:+B$* T�* 02@(:+<�6-3L�(�7-'�)(S<� 0 !-q!�)P��$&�(23 %2 +<- (&3' {)L�(�=($(H�1�ª>� /�($Q�%�J23 %�,)3+<(: ^�4+��6-'+9l,2/�)-�($2M3L�)-��6 %�+CqEG3' ? %#$ %$Q�6+.-P��4(&��-�2L�0$,2��^'>��$^)[ +$,�4�6-L�(�W�(!�(&3' !-�(*+.2%�)(:+<�6- +<- A� 02@(:+.��- � C � C u C u �($4 £!'-�$* %�(�.+B�4(*+.2(C � +$*�0:]\"-3�o�.�< %2��� �*2M33 %#$ %�W�($4 f(&33 f(:+B) �('��YU6 +$Q>����($,�� f+<20 %<� %$Q�S'>��$ )[ +$,�4�6-L�(���(!3(,3' 0-�(:+<2/�)(*+.�6-�����-P2 +U� %$Q>�(,3'+.-��� +���4 $* +���)(*+.-��I(*�/2+$Q>;)3(*����$&�0)�3'+.2%�(���Z>g<L�0�* %2��6-' :b(:+B#/ F(*��\� !-��(!�(&3' !-�(*+.2%�)(:+<�6-��42M3' %#$ %�+�N<3+.��#$ !(,$*+.2+�%�L�)-�2��(,3' %$ �()�)�$4�?��2M3' +��+B�-�<���4({+<-?(,3' I�Q3"!��$ R<?>�(&3' I#/ !-�(*+.�6-3+.-��B�6-P�B>^�0 +$*�S\"-3�o�.�< %2��� (CG�£-'2!+�2' !-�(&�(���Z>��(&33+��;+B�e�)-A�($* %�k+.-T�.3'+.2M3/(&3' F+B#S)P�.+.2!+<(ª+<-'2%�B!��*+<�6-$�('8(&3' <L�(�4+.2}E-�HAx�=� tvu(���mz ��«F��« ��u(��� C u�0 :=AxE.«W¡�(�=��#S��-�2��)(:��$V>Y�4(&��-�2L�($Q2�+B��#$+��Q�. %�(2'+.-P����<� 02/�0!��* {(&3L�)(=2'�"2%!�#$ 0-�(=�6+BU� %�D(&3' -2'+B�4(:+<-'2!(n+B#S)�$4 %�Q�*+.��-(&3��)(�lP�� %2�$* +!��&�(<P�. �)L�(�Q�Q�1��$,2P�1�($4 �)[ +$Q'> !2!(&�Z> �(23 %�"!L�)(* �� � + �3 +2 )L�(�,�V�;�($,2����($* �+<- �6 0-3 %$&�0�6�2'+B�&�(�=(: %$ �J��+9(:+<-��/(*�A3L�()�)� 0-D�� %�,)� 02!+��(�B�B>?+.-13'+���3P�B>^2'+B�4(&$4+�<�!�(: %2 0-?U"+�$*��-�#/ !-�(&�8�C+<(,3 20�(#S)��6-' !-�(,��('�!'-�\�-'���C-�(,$,!��=(H�;�($4(&33+.-' +�,�%C

�/sutvs�� |Ai�� ��f"� �onu�� ��lf |gk�� �p|gkm`�Fn�/fx`���iFkof �fy[�F`�f�" �Eo�}�6+ZU6 ��*��#$ D [�P�(#T)��. +���('x�.3L�)(�+��o-' 0 +2' %2f(:�-<�$*+B2��6 D(&3' ��?�()����(#$�6-��H(&33 n(* 02M3'-'+<2/�(�x�($42M3'+<(* 02!(,!�$* +��('ªg(E�5� D %$Q�*+<�6- � C � �,�()[ +$&�)(*+.�6-L�0�D�($42M3'+<(* 02!(,!�$* +�%�N��-�2{�Q>;�4(* %#T�}�0$*2M3'+9(: 02@(&!�$4 %�+�N�4 +U6 +$&�(�l�=(: %)P��-' ! %2(:�Y<� (M�(\) 0-DC

� EG33 }$* +�"!'+�$4 %#$ 0-�(&�=)�$*�"20 +�,�e#4!��4(e�(2�2�$4 %�Q�;(&3' .'K!��B�j���(#R!3(n�('a$4 %�< +U0��-�(e$4 %�"!'+B$* %#$ 0-�(,�%�"+.-'2+��!�2x:+<-��I-'�)(��Q!��4(.�4 02%!P$*+<(H>(�<�!3(-�(�B�*�B��U6 +$&�(�B�D�Q>;�4(* %# �Q!�$QU"+ZU(�0<'+��<+<(H>��x$* +�.+��0<'+��<+<(H>��?)� %$V'>��$,#S��-'2! (�L�)-�2�)(&3' +$R2' %�4+�$,�(<��. O�)(*(,$*+B<�!3(: +�%C£�£-��6 !-' %$,�(�§� +9(I2%��-�<[ 5 �"(&$* +#/ +�B>ª2'+ �$2+!��<(f(:��$* @(&$4��l'(Y��-?> �('(,3' %�4 A�)(4(&$*+B<�!3(* %�I+<-�(*�����V>x�=(: +# (&3��)(4�e�(�X)�$4��2+!�$* +2 ��$4�Q)[ !20+<l' %2 +.-x(&3' A�0<��* !-'20 ��('-�Q! �X:2!+. !-�(e\�-'���.�. %2P�6 �('8(&33 8'K!�����* @(C�('l$* +�"!'+�$4 %#$ 0-�(&�+C}� m���1 +U6 +$%�L�4 0 t &�00z '>�($J�k2!�6-�(&$&�0$Q>OU"+< +�WC¢¡EG3"!��+��#R!'2M3I��$* %�)(: +$l��!'+�2���-'20 n+��l$4 %�"!'+�$4 %2f+.-W'r��20+B�.+<(&�)(:+<-��1(,3' n %�4(&�(<��<+��,3P#/ !-�(��('��{2!��#S)��)(:+B<��. �)-�2O$4 /�(�<+��/�0<��. .�* @(e�('l$4 %�"!'+B$* %#$ 0-�(,�%C*EG3' F ��+��4(*+.-��f20�6-320 %)�(H�('�(,3' ���)� %$,�)(:+<�6-L�(��0$*2M3'+9(: 02@(&!�$4 )P$* %�Q!�#S�(<��B>�#R!P�4(ª+<-'2%�B!�2' G�}�Q! �$20+< 0-�(&�Z>I20�(#S)��< !(* e$* +)�$* +�* !-�(&�)(:+<�6-7�(',(&33 H-' 02! %�,�,�($Q>R$* %�"!'+B$* :#$ 0-�(,�%C� EG33 f2!�6-'20 +)3(m�('*�Y�6 0-3 %$*+<2(�v��$-�(<��=(&$,��2!(%�N�0$*2M3'+9(: 02@(&!�$4 f+B�C20��#T)��. @(: +�B>g#$+��Q�*+<-��X'K$*��# (,3' ��!3(Q:�<+.-' +2g)�$4��2! %�,�+��'r�(���<+.-��I�*��#$ +�.33 %$* W<� !(H�1 0 !-�(&33 ��)[ +$&�)(*+.�6-��(���0$*2M3'+9(: 02@(&!�$4 S���R�* @({�('F$* %�"!'+B$* :#$ 0-�(,�M¡=�)-�25(&3' }�Q>;�4(* %#T�G�($*2M33+<(: !2!(,!�$* Y�°�.3'+.2M3A�4 0 +#S�H2+�.���4 %$1(*�X�4�Q)[ !20+<l'2F+�#T)��. +#/ !-�(M�)(*+.�6-¡ C�£-P(&33+��R�4 02!(*+.�6-|��-P2 +.-|�e3L�()�(: %$ � ��-p2+$*+9(: %$4+��P���; A)L�)+.-�(Y��$&��(&3' +$B-' %�?��(:+BU� g)'+<2!(&!P$* ��('C(&33 2'+ �/2+!��<(*+. +�D(,3L�)(=3L�/U6 6�0$*+��4 0-S$* %)� /��(: %2P�B>$+.-T)�$*�"2%!P$*+.-P���"2' +U� %�.�()'+.-��P����)� %$,�)(:+<-����"!��4+.-����x��-�2S#O�)+.-x:(M�)+.-'+<-��A�g�C+�2' RU0�($4+. @(H> �('�)����,�4+�<��Z>�!'-�$4 %���)(: +2 �V>;�4(: +#S����-P2�(,3' 0+B$ -' !(H�1��$Q\� %2 +.-�(: +$*2!�6-'-' !2!(:+<�6-��+C��A" 0 tvu �(�oz '>��$e��-� +���(<���$,�)(:+<�6-O�)-�2A��-L�0�B>;�*+B�1�('l�4��#$ ��('�(,3' 8$4+��,\"�1+.-?U6���ZU6 +2DC ¡ �F-�(,3' ���(,3' %$e3L��-�2D�(&33 6E� !2M3'-'+.2%�(�a5}$42M3'+<(* 02@(&!�$4 �23��2+!�#/ !-�(.2'�� +�.$* %)P$* %�4 0-�(}�R)[���Q�*+B<��B>O!��* ['K!��a�4(* %)�(:���e�($,2G(&3L��(.�6�?�(�+B'��,!P)�)��. +#/ !-�(: %2^�C+<(,3��)(&3' +$ �0)�)�$*����2M3' %�+C=�b(-#R!P�4({-'��(.<� W�* 0 !-��(�.�Y#O�0�6+.2F2%�($,)� !({�6-^�.3'+<2M3{�1 2/�)-{��>G+<-�(:�B(&3' 6'K!3(,!�$* 0C d W<[ +�.+. [U6 (&3��)(C(&3' fg(EF5��)-�2�+<-�2' ! %2�(,3' �20�6-320 %)�(��('�(&3' (,3�$* ! I5 $,#4>�,�($42M3'+<(* 02@(&!�$4 %�,��2!��!���2X<� G#R!'2M3Y#$��$* ; +�[ 02!(*+BU� H+B'v(&3' ;20�6-�(: !-�(&�n�('���!�$�$4 %)���$4(��0$* e(M�0\� 0-Y�4 %$*+<��!��Q�B>�C

¸ 3�

Page 181: Practical Architectures for Survivable Systems and Networks (Phase

JLK � MPOFQ�� T�� � Tn]D^��{QZYZcF`vU£W�� _a`,Y�O UbW'QZY�W'cF`,QEG3' �«F�?« ���?�0�IA� !2%!�$4+<(H> 5}$*2M33+<(: !2!(,!�$* ��r« �fAx58¡[�. D����!P#/ � �('7(&3' �E� !2M3'-'+.2%�(�R5 $*2M3'+9(: 02@(&!�$4 � $&�(#$ +�1��$Q\�'>�($S�£-P'>�($,#S�)(:+<�6-©@���-L�(�6 +#/ !-�(£�rEF5 � �V@�¡/+��$+.-�(* 0-�2' +2L(:�~$4 %)�$4 %�4 0-�({�(<��=(&$&�)2!(A�)-�2�6 !-' %$4+.2Y�Q>;�4(* %# �($*2M33+<(: !2!(,!�$* +�%CgEG3' O« �fA;5 �)-�2x(,3' S« �fAx5 EF$&��-P�*+<(*+.�6- *���)- '>��$W<�$4+.-���+.-���(&33 « � Ax5�+<-�(*�A$* %�(�.+9(H>1�0$* R<���(&3�2!�6-��4+�2' +$* %2�(*�A<[ R�<+BU"+.-P�O2'�"2%!�#$ 0-�(,�%�l��-�2 (,3' %$4 +'>��$4 I(&3' X$4 /�(23 %$F+B� 0-320��!�$,�(�6 +2 (*� 2M3' !2M\P(&3' 5��-x:H�<+.-' T�*��!P$*20 +�X'>��$f(,3' A���)(* %�=(4U6 +$,�4+.�6-��r3�(4(&)D² � �m�G�G�WCj+<(,�*+§Cv2'+B�&�PCv#/+B����¡ C1m-x'>��$4(,!'-L�)(* %�B>(�3(&33 [U6���B!3(:+<�6-G�('o(&3' +�* �2'��2+!�#$ 0-�(&�.3L�(�.<� 0 !-1$* +���)(*+BU� %�B>S�,�<���WCEG3' �« � Ax5 $* !20����-'+��! %�%�j�(#$�6-��B�)(&3' +$e(&3'+<-����%�a� w ¡1(,3' �+�#T)[��$=(M��-320 F�('�2'+Z�� +$* 0-�(.�4 02%!P$*+<(H>^)����<+Z:20+< %�+�*� u ¡C(&33 R$* %�(�.+9(H>�(&3L�)(}!��* +$,�W��-P2�$* %�4��!�$420 %�6#S�/>{3L�/U6 X2'+Z�� +$* 0-�(}�* 02+!�$*+9(H>��)(4(&$4+�<�!3(* %�+�*� � ¡C(&33 %�Q�* !-�(*+��(�Z-L��(&!�$4 �0'�2'+B�4(,$*+�<P!3(: +2{)P$*�"20 %�Q�*+<-��O�)-�2�-3 !(H�1��$,\�+.-P�����-�2�� y ¡1(,3' �-' 0 +2�'>��$H2!��#T#R!'-'+<2/�m:(:+<�6-�� (*�F(M�(\) -)P����2! H�oU� %$�)���(: !-�(*+��(�B�B>�!'-�(&$Q!��4(H�1��$=(&3?>$-' !(H�1��$,\"�+C��b(�#S�/>R<� -�8!��* ['K!���4(: +)T'>�($Q�e�($,2D�<�!3(C(,3' W)�$*�"�('��('�(,3' W)�!�2�23+.-��7+��H+<-�(&3' � /��(:+.-P�S�)-�2G+<(&�G)���(* 0-�(:+��(�D!3(*+��.+9(H>�+B�H-'��(G>� !( $* /�0�.+��! %2DC5�$* !20 !-�(o ���0#/+<-L�)(:+<�6- �('�(&33 =« � Ax5 +B�a�6+BU� 0-W<?> � %!��=(: %�"�)-�2R@���>�l, +��2 t w/�!�oz �m�.33�-$4 %#S�($,\{(&3L��(� o %$,3��()���(,3' J« � Ax5�2'�"2%!�#$ 0-�( 2%��-R<� %�=(�<� �U"+. [�; +2Y�(����20�6-320 %)�(&!L�(�"'K$&�0#/ [�;��$Q\6'>��$�23+��*2+!��,�4+.-��}��* !2%!�$4+<(H>A)����<+.2+>S��-P2�+<(&�;+�#T)��. +#/ !-�(&�)(:+<�6-DCv� m���1 +U� %$%�,(,3' W« �fA;5 �. %��U� %�H2!��#S)P�. !(* %�Z>���)� 0-g�.33+.2M3�* !2%!�$4+<(H>O)[���<+.2!+. %�=�($4 �(:�R<� F+<-"U���\� +2DC;A� 0 6�0���*�R9Z���.#S��-^��-�2{@?���*+< %$ t±w�0!�oz ��+.-?U6 +�4(:+B�?�)(*+.-��k(,3' 8!��4 �('�« � Ax5 �0�6�g)[�(�,�*+B<��. I#/ @(&3'�;2'���<���(>A'>��$ �Q>;�4(* %# 23 +U6 +�.��)P#/ !-�( ��-�2��6+ZU"+.-��$(H�;��+B����!P�4(&$,�)(:+ZU6 �Q>;�=(: %#T�-�*�T2' %�42%$*+B<[ +2DC5�2!20��$Q2'+.-P�m(:�m(&3' e« �fAx5|2'�"2%!�#$ 0-�(%�?��-A¦[¤[¥r­Q¦"�[¥F¦(­:� ®°¥�¨��[¥r¬x­&¨F��$4���.� ��!3(��(',(&33 e$* +�"!'+�$4 %#$ 0-�(&�!�+<(F2' @l,-' +��)�$*+<-'20+B)��. +�F��-�24'K!'-P2L�(#$ 0-�(M�(��2!�6-'20 +)3(&�+�?��-�2I'K!'-'2!(*+.�6-P�o(,3L�)(��&�)(*+��Q'°> (,3'���4 e$* +�"!'+�$4 %#$ 0-�(&�+C5X&;¨@��¨[­ ®��-¦(­:� ®°¥H¨��[¥�¬;­&¨��(2�2��*�Q)[ !20+<l'20+<(H>f(:��(,3' H20�(#S)��6-' !-�(,�*��-�2Y�4 02%!P$*+<(H>4#/ !2M3L��-'+B�,#T�%C�5 ¯.�*&(®��,¦(¯¦(­:� ®°¥�¨��[¥r¬;­M¨8�()�)P�.+. +�8�g�6 !-' %$4+.2Y�($42M3'+<(* 02@(&!�$4 I(:�^�g�* @(��('�3?>x)���(,3' !(*+.2/�0��$* +�;!3+�$* +#/ !-�(&�%C � +.-��(���Z>��j�¤ �L¨��[® �e� ¦(­:� ®°¥H¨��[¥�¬;­&¨^�()P)��.+< %��(&3' £�<���6+.2%�(�8�0$*2M3'+9(: 02@(&!�$4 x(*��$4 /�(�6$4 %�"!'+B$* %#$ 0-�(,�%�8�, +�,3' +� ��!3(?(&33 2' +�*+���- (:�5 !-L�(<��< I+�#T)��. +#/ !-�(M�)(*+.�6-D��)-�2£�(2�2�$4 %�Q�* %�W�Q)[ !20+<l'2B20��#T)[��-' 0-�(&�+��+.-�(* %$Q'r�)20 %�+�D�4(&��-�2L�0$,2��+�)� %$Q'>�($,#S��-'20 0�L��-�2?20�(�4(/C� ��$-2'+��42%!��Q�*+.��-�)�!�$Q)[���4 %�+��(&3' f��U6 %$VU"+. +�N�(' (,3' 4EF5 � �V@ U6���B!�#/ +�}�6+ZU6 +�m(&33+��}�Q!�#T#O�($V>G�('ª(&33 EF5 � �V@  D�(��!�#$ � ²1EG33 �« � Ax5 �,�(2�2�$4 %�Q�* %�O�* 02+!�$*+9(H>|$* %�"!'+B$* +#/ !-�(,��2!��#S#$�6-��Z>�'>��!3-�2��C+9(&3'+<-«F�?« ��$,����-'+��%�)(:+<�6-��+�D#/+B�,�4+.�6-�� �($�23 %$*+ZU6 +2~�(�I�{$4 %�Q!��<( �('; [�P�(#$+.-'+<-��^#/+B�,�*+<�6- (&3P$* /��(&�%C � !P$4(&33 %$%�(&33 ª« � Ax5 )�$4��U�+B2' %�����6 0-3 %$&�0���=(M�)(* %#$ 0-�(��(<���!3({� 20��#T#/��- 20���B�. 02@(:+<�6- �('R�4 02+!�$*+9(H> �* +$QU"+.2! %���-�2�#$ 02M3L�)-'+��Q#S�I(,3L�)(T��- +.-x'>��$,#S�)(:+<�6-��V>;�4(: +# #/+B��3�(I�(�[ %$I(,3�$*��!P��3 +<(&�X�� 0-' +$*+.2�2!��#T)[�6-3 0-�(&�+CEG3' ^« � Ax5 �(�B�*���Q)[ !20+9l, %�Y)�$4+.-'2!+�)��< %�%��20�6-'2! %)3(,�%��'K!'-'2@(:+.��-��%����-�2��4 %$VU�+<20 +�7(,3L�)(I(&�($,�� !(X�4 02%!P$*+<(H>2/�0)L�(<'+B�.+<(*+. +��(:�I��!'+�23 -�V>;�4(: +#��0$*2M3'+9(: 02@(&�1+.-T2' +U� %�.�()'+.-�� (&3' !+�$��,)� 02!+<l,2}�($*2M33+<(: !2!(,!�$* +�%C*EG3' �6 0-' +$*+<2�* !2%!�$4+<(H>©�($*2M3'+9(: !2!(&!P$* �)�$4�oU"+B2' %�^��- +<-'+<(*+��(�.�0���.�"2/��(:+.��- �('��4 02%!P$*+<(H>q�* +$QU"+.2! %�^��-�2 'K!'-32!(:+<�6-��A�)-�2<� %�6+<-��/(*�~2' !l'-' (&3' �(H>x)� %���0'�20��#T)[��-' 0-�(&�g��-�2 �* !2%!�$4+<(H>�#/ !2M3L��-'+B�,#T��(&3��)(A�($4 ��/U0��+����(<��< G(*�+�#T)��< %#$ 0-�(e�4 02+!�$*+9(H>A�* +$QU"+.2! %�%C��£-{�(2�23+<(:+<�6-D�" [�P�(#T)��. +�G�($4 8)�$*��U"+�23 %2G�('l3'���a(:�X!��4 F(&3' W« � Ax5S+<-2' [U6 %�<��)'+<-��Y#/+B�,�*+<�6-x:]�. +U� %��(: 02M33-'+.2%�(�F�($*2M3'+9(: !2!(&!P$* %�+C��5}�9(&3'�(!���3 �* 02+!�$*+9(H> )[���<+.2[>�+��W�. ['%(�!'-��,)� 02!+<l, +2 +.-�(&3' S« � Ax54�8(&33 S$4 %�"!'+�$4 %#$ 0-�(&�4�($* Y'>�"2%!��4 %2�6-£�* !2%!�$4+<(H>£�)-�2ª23�?-3��(��(2�2�$4 %�Q� �)(&3' +$ +B#S)���$=(M��-�(6�0�,)� 02!(,�f�0'=�Q!�$QU"+ZU(�0<'+��<+<(H>�CI�£-£)�$*+<-'20+B)��. 0��(&3L��(�,33��!���2 -'��(O<[ ���-L��<P�4(M�)2%�. ?+B'�(&3' �« �fA;5 +B�S�Q! �$20+. !-�(&�B>|�6 !-' %$,�(�C(:�� !-'20�(#S)L�0�,�g�Q!�$QU"+BU0�(<3+��.+9(H>$* +�"!'+�$4 %#$ 0-�(&�6�0�}�; +����C EG3' B �"(: 0-�(F(*�O�.3'+<2M3 (&3'+B� �C+��B�l<[ I)[���Q�*+B<��. I$* %#S��+<-��{(*�g<� R�* ! 0-DC6�£-��)-">2/�0�* (�v+<-1�e3��()3(: +$ & �1 4�02�2�$* +�,� �($*2M33+<(: !2!(,!�$&�(�a�=(&$Q!'2!(,!�$* +�m(&3��)(C20��!P��2? 0-�3L�)-'20 �(&3' W$4 /�(�<+��/��(:+.��-5�('(&33 ��� 0-' +$&�(�<+��0 +2^�,!�$VU�+ZU0�(<'+��<+<(H>S$* +�;!3+�$* +#/ !-�(&�C��!3(,�.+.-3 %2G+.-{�e3L�0)3(: +$ � C

¸ 3��

Page 182: Practical Architectures for Survivable Systems and Networks (Phase

JLK � RHT;U=V;WX_aU=`��fT1`vVFQ ��� ����� M _X`,Y�O U£W3QZY�W,cF`,QEG3' mg��6+<-�(�5m+�$Q<[��$4-' CAx� �6� � E�5}$42M3'+<(* 02!(,!�$* I�hg(5 Ax58¡nA�(M��-�2��($,2�� ��-�2�<����(\ t±wouxw+z �hg�A 8¡�+<-'2%�B!�2' +��e3L�()�(: %$ & �hA� 02+!�$*+9(H>�A� %$VU�+<20 +�M¡=�)-�2S5m-'-' � w�� �r�£-x'>��$,#S�)(:+<�6-/A� 02+!�$*+9(H>T��-�2S�£-P'>��$,#S�)(*+.�6-/A;>;�4(* %#T�A� !2%!�$4+<(H>��ª-���+.-' ! %$*+<-��"¡ CªEG3' A3���-�2�<����(\j�v�T�e3L�()�(: %$ & ��-P2|5m-'-' � w�� �()�)� /�0$k(:��2%�($,$V>P�6- (&33 20�"��\"<�����\$2M3L�($,��2!(* %$4+��4(*+.2+�H�('Z(&3' g(EF5���-�2^« � Ax5k�"(&3' [>A�)(4(: +#S)3(;(:�B %���(<���$&�)(* F�6-5(,3' g(E�5��)-�2(&33 1m-3+<l, +2��e$Q>;)3(*���.�(�6+.2W5}$42M3'+<(* 02@(&!�$4 ^� 1}�e56¡[��.3'+<2M3��,!�#T#S�($*+B�0 %�H(,3' 4)�$4+�#S�($Q>52%$Q>;)3(*����$,�()�3'+<2�4(&��-�2L�0$,2��+C*5}�<(,3'��!��(3S�Q!'2M3A��-$ 0-"!�#$ %$,�)(:+<�6-/�0'D�4(&��-�2L�0$,2��1+��D20 +$4(M�)+.-��Z>B-' 02! %�Q�&�($V>��3+9(��. /�/U� %��#R!'2M3!'-��Q)[ !20+9l, %2���-�2|2'�" %�B-'��(T�02�2�$* +�,�B(&33 ?+B�,�Q!' ��('m20��#T)L�)(*+�<'+B�.+<(H>��D+.-�)��($4(*+.2%!P���($+�ª+<(X�< /�/U6 +�S�0�Y��- [�� +$*20+B�* (:�B(,3' 6$* %�(2' %$.3'��� (:�Y��2M3'+< +U� f2!��#S)��)(:+B<'+��<+<(H>Y�(#$�6-��B+<-'20�(#S)L��(:+�<P�. �()�)�$4�?��2M3' +�%C��b(-�(���4� [�x3'+B<'+<(,�O� $* +#O�($Q\m�(<��. A'r�(�420+<-L�)(:+<�6-��C+<(,3©�ª�4 02+!�$* ��*+.-P���. ^�*+B�6-x:b�6- �hA'A'A �W¡Y2' %�Q)'+<(* ?(,3' 1$4 /�(�<+<(H>(&3��)(T#O��-?> �0'�(&33 ?2!��#T)[�6-3 0-�(&�S�(�.��-�� (&3' ^�e��> (H>;)'+<2/�(�B�B>�2/��-'-3��(O<� �(&$Q!��4(* %2DC�EG3'+��Y�* ! %#T�$(*�<� g��#$�6-��=(&$4��!�� �oU� %$Q�*+�#T)��<+<l,2%�)(:+<�6-D�F��-�2P+B�I2���-��6 +$*��!��I<[ !2/�(!P�* 5+9(f+B�I�<+�\) %�B> (:� !-'20��!P$&�(�6 S�*+B#Y:)��<+��4(*+.26�4����!3(*+.�6-P�{(,3L�)(}�($* -'��(}�(2' +�;!��)(: +�B>{�* !2%!�$4 (C-EG3' 43L�)-�2�<�����\A23�� +�}$* !20����-'+��! f(&33 f-' ! %21'>�($A'A'A � �()�)�$4�?��2M3' +�B(&3L�)(72%��- ��U6 %$420��#$ �(&3' ^2'+ �$2%!��9(:+. +�X�($4+��*+<-���'K$*�(# #R!��9(:+B)��. S�(!3(,3' 0-�(:+<2/�)(*+.�6-P��u 0C��PCB�*3L�/U"+.-P� (:��$4 %#$ %#R<� %$I2'+B�[ %$4 0-�(Y��2!20��!3-�(R��«8�X��-�2~)��(�,�V�;��$Q2��M¡ �=<P!3(I(&33 g$*+B�,\"�k�('H(,$,!��=(:+<-��!'-�(&$Q!��4(H�1��$=(&3?> 2!��#T)[�6-3 0-�(&� ��-�2?(&3' ��* +$*+.�(!��.$*+��Q\"�m�('�lP�� %2�)��(�,�V�;��$Q2���(,3' %#T�* +�BU6 +�}�0$* -'��( �(2' :�"!L�)(* %�B>520�6-��4+�2' +$* +2DC ��A� ! kA" 02!(*+.�6- & C � C � C y C u �('o(&33 ��� g(!'-' w i6i 0 2�$,�0'%(C�('o(&3' g(5FAx5NA"(M�)-�2L�($Q2�� }�)-�2�<�����\�� D +$,�*+<�6- � C � C ¡JLK� _ V� �kQoV�� � ���"W3Q������x`,T{Y8Q���� �±T1` � T �EG3' l,-��(�8�4(,!�2P>q$* %)���$=( t�u &;w+z �0' (,3' �8)[ !- A;>;�4(: +#S�AE��(�Q\ � ��$*2! �����AxE � ¡$+��52!�6-'20 +$*-' +2�)P$*+Z:#S�($*+B�B>��C+9(&3p(&3' �$*���< G(,3L�)(/��)� 0-©�V>x�=(: +#S�g#$+��(3�(Y)P���/>p+.-�«F %)L�($=(&#$ 0-�(/�('W«F +'> !-��* �20��#T)�!3(* %$�:20�(#S#R!3-'+.2%�)(:+<�6-X�Q>;�4(* %#T�%C�EG3' -$* +)[��$=(�'>��2+!��* +�;�6-7(&3' -$* +�"!'+�$4 %#$ 0-�(&�n�('a�)-/��)� 0-;:H�Q>;�=(: %#T�e)P$*�"20 %�Q�'>��$ «F�?«R�j��-�2 2M3��($&��2@(: +$*+��! %��(,3' R�02PU0��-�(M�(�6 +���('�(&3'+B�8�()�)P$*�?��2M3�C EG3' 4�4(&!P2P>1�($*��!�)�20�6-P�*+��=(&�F�0'��2'+B�4(:+<-���!'+B�,3' +2^��$*��!P)?�0'�-'��-��6��U6 +$*-�#$ 0-�( )[ !��)��. 0���,)��6-��4��$* +21<?>�(&33 I«F ['> 0-��4 fA�20+< 0-'2! �;���($,2DC5�U� %$Q>�20��#T)� %���<+.-��{�4(&�)(: +#/ !-�(7+��I+<-'2%�B!�2' %2�+.-P(&33 A���3 !2%!3(*+BU� A;!�#S#S�($V> �0'{(,3' ��AxE � ²8�Q�£-'r��2@(/��(,3' 6E��(�,\ � �($*20 W�0$,��!' +�;(&3��)(G#S�o�4��$G«F�?« )P$*+.�($*+<(*+. +���,¦��,���m¥�[¨W¦"� ®§¨��(¨*� �C+<(&33��!3(.�R#S�(�,�4+BU� +.-x'K!��*+<�6-��('��8)� 0-GA">x�=(: +# �)(4(&$*+B<�!3(* %�1(,3�$*�(!���3A��-���$,�?�)-'+��! %2 �8)� 0-?A;>;�4(* %#T� *$*�"20 +�,�%C1A��(#/ �*��$=(�(' �8)[ !- A;>;�=(: %#T� �$4��2! %�Q� #R!P�4(.<� 020�(#/ (&33 I«F��« �X®%���m¤�¨[¥D��-�2 ���m­M¨k����� �L¨[¥�¨@�������¢�d S#S�(\� O��2'+B�4(*+.-'2@(:+.��- 33 %$* O<[ @(H�; ! 0-P(&33 ���)� 0-x:]�Q>;�4(* %# 20�6-320 %)�(^�K�.33+.2M3P+B#S)��<+. +�6)�$*+B#O�($4+��Z>(&3��)(T3' !(* %$*�(�6 0-' !��!��Q�B>�2'+Z�� +$* 0-�(T�Q>;�=(: %#T�$2/��-p+.-��*�(#/ ^�* !-��* �+.-�(: +$*��)� %$,�)(: /¡R��-�2 (&3' ?��)� 0-x:]<[�/�20��-'20 +)3(423+��*2+!��,�4 %2P+<- A� 02@(:+.��- � C w�� �K�.3'+<2M3©¦����(®°¥r®����j¦(¯°¯ �I+B#S)��<+. +��(&3L��( (,3' Y�*��!P$*20 /20�;2' T��-�2x+.-x:(: +$Q'r��2! %�X�0$* O)P!�<��.+<2%�Z> ��U0��+B���(<P�. B+.-ª�*��#$ O#$ /�)-'+.-��0'K!����* 0-P�* �¡ C @1��-?> �('e(&33 A�($,�(!�#/ !-�(&�I'>�($f(&33 ��)� 0-x:]�Q>;�4(* %# �()P)�$*�?�)2M3|$4 02!��#S#$ 0-P2' %2�<?>P(&33 � A;E � $4 %)���$4(T�0$* ^�(�B�*��$* +�. [U(�)-�(T�0�X#/��(*+BU0�)(*+.�6-'>��$G)�!P$,�,!3+.-��B(&33 +<-�(&$*+<-��*+<2/�(�B�B>7��)� 0-;:H<����A�()�)�$4�?��2M3{$* !20��#T#/ !-�2' +2?+<-�(&3'+B�G$* %)���$=(/C m���1 +U� %$%�v(&33 ��)� 0-x:]<[�/�g�()�)�$4�?��2M35+B�;+<-5��!�$1��)'+.-3+.�6-S#R!'2M3A#$��$* {20��#T)� %���<+.-��I��-�2O#R!'2M3A#$��$* -'r�($V:]$* /�)2M3'+.-��PC��£-��-?>� [U6 0-�(%�j�1 W�4(&$4�6-����Z>A!�$Q�6 F(&3' �«F�?« (:�7 !-'20��!P$&�(�6 W<���(&3G [����$=(&�+C

¸ 3��

Page 183: Practical Architectures for Survivable Systems and Networks (Phase

� � � ��� � ��� � � ��� � � �� � � � ��� ����� ��� � ���

�; !2/�(!��4 �(,3'+��T$* +)[��$=(g�02�2�$* +�,�4 %�g�4��#/ ?�('m(&3' �#/���=(Y'K!'-�2L�(#$ 0-�(&�(�.�.+�#$+<(&�)(:+<�6-��f�('F2!��#S#$ %$420+��(���Z>�/U0��+����(<��. ��V>x�=(: +#S����-P24�.3L�)(*#4!��4(*<� e23�6-' ;(*�F��U6 %$420��#$ e(&33���* J�<+�#$+<(&�)(:+<�6-��%�%$* %�4 /�($42M37+����0'v2%$*+9(:+<2/�(�+�#T)���$4(&��-'20 �(:�O�,!�$VU�+ZU0�(<'+��<+<(H> <[�)(&3 (,3' I+.-320��$Q)[��$,�)(:+<�6-?�('ª�6-����6+.-��S$* +�* /�0$*2M3 ��-�2 (,3' I2!�6-�2�!'2@(�('Z-' [��$* %�4 /�($42M3�(&3L�)(;2/��-A33 %��)/(:�klL�B�[+<-/(,3' 8�?�()P�%C*5}�J�k20�6-P�* %�"!' !-'20 0�v20�6-��4+�2' +$&�(<P�. � +#S)P3L�(�*+B�;+B�)�����20 +2 �6-�$* +�* %�($*2M3£$* ['> %$4 0-'2! %� +.-�(&3' 4'>�(���.���C+<-��Y<'+�<��<+.���($&�()�3?>(C 5 �<(&33��!���3 -3 +���(2�2'+9(:+<�6-��C(:�5(&33 �.+9(: +$&�)(,!�$* I�($* k20�6-�(:+<-"!L�(���Z>G %#$ %$Q�6+.-��P�j�1 X3L�/U6 Y�)(4(: +#S)3(* %2 (*�O'>��2+!��F�6-�(&3' R)P$*+�#S�($V>�$4 +'> +$* 0-320 %�+���-�2{)L�($=(:+<2%!����($,�Z>$(,3'���4 �(,3L�)(-#$+���3�(H+B����!P#/+<-L�)(: -�Y3'+��(3��B>S)�$*+<-'20+B)��. +2^�()�)�$4�?��2M3G(:�T�,!�$VU"+BU0�(<'+B�.+<(H>(Cd k20+9(: �3' %$4 X�T'> [� $* +'> +$* !-'20 +�F(&3L�)( 3L�/U6 X<� 0 !-�)L�($=(:+<2%!����($,�Z>�+.-P��!' 0-�(:+��(�Z+.-?(&3'+B�})�$4�m�4 02@(/�D�)-�2(&3��)(=�1 �2!�6-��4+�2' +$n(*�I<� ��('�3'+��=(:��$4+.2%�(�L�*+B�6-'+<l'2/��-'2! C+.-O!3-�2' %$Q�4(&��-�2'+<-��f(,3' m+B#S)���$=(M��-'2! C�('a�($42M3'+<(* 02 :(&!P$&�(�*�=(&$,!32!(&!P$* g�)-�2 +9(&��+�#T)��<+.2/��(:+.��-��%CR5 �<(,3'��!���3�(&33 T'>���B�.���C+.-P�g�,!�<P�* !(k�('J$4 +'> +$* 0-320 %�k+��6���0$,�6 +�B>20��-'20 +$*-' +2~�C+<(&3��* 02+!�$*+9(H>�� +9(R�0���*�{)�$4�oU"+B2' %�R#S��-?>£U0�(��!L�0<��. 7+.-P�*+��(3�(,���C+9(&3ª$* %�Q)[ !2!(I(*����2M33+. +U"+<-���,!P$QU"+BU0�(<'+B�.+9(H>N²� d +B���<+�� d �($4 (�v� w i!&(� $* +)[�($4(G'>��$e(,3' �«F +'> 0-P�* kA�20+< 0-'2! �1�?�($,2 t � 0!&oz� g�+B#�5m-�2' %$Q�*�6-���� w i!&�u $4 %)���$4( t±w��0z� @{!��<(*+.2%�+���-U"+�$4(,!L�(�F#/ +#/�($Q>��j�* +��#$ 0-�(M�)(*+.�6-��N)L�0�6+.-��P�N3'+< %$,�($*2M3'+<2/�(����2!20 %�Q� 20�6-�(,$*���B�%���V>;#R<[�(�.+.2-��(#/+<-��^��-�2��(�.+��(�*+<-��O'>��$ lL�< %�I��-�2x+.-�)P!3(Q:b��!3(&)P!3(��4(&$4 /�(#T�%�F2P>"-L�(#$+.2Y�<+.-�\�+.-P���D2'��#S��+<-x+B�*�0:���)(:+<�6-D����-�2 (&3' A!P�* ��(' ��3'+��(3' %$�:H�. [U6 +�e�Q>;�=(: %# )�$*���($&�(#T#/+<-��1����-���!��(�6 �+<-P(&3' w i ��� � t 0?u �0(� � u &�uoz ��'>���B�.���1 %2 <">���$4 %2' +�*+B�6-���-�2�$* !(,$*��l3(I�('e(,3' O\) %$4-' %�n(:���)2020�(#S#$�x2��)(: Y#R!��9(:+B�. +U� %��4 02+!�$*+9(H>5+.-5(,3' w i!&0� � t �!��uoz �3(H�1�Y)L�()� %$,�H��-A�. %�Q�*�6-P�-�< /�($4-' %2 t & � � &��mz�t �£-'2!+�2' !-�(M�(�B�B>��"(&3' 6���(�4($4 %#S��+.-3+.-��S@�!��9(:+<2%�{+.-��=(M�(�B���)(*+.�6-g�e�(�}23 020�(#S#$+��Q�*+.��-' %2�+.-�� 2@(:��<� %$ u(����� �{�7l�U6 :H)�$4��2! %�,�4��$�V>;�4(: +# !��* +2�'>��$ w�0 >6 %�($,��<?>�(&3' S�J��-��(2'+��)-ª«F +)L�($=(&#$ 0-�( �(' � �)(:+<�6-L�(��«F +'> 0-320 O@1�($*+9(:+B#/ �;�(#S#S��-�2D� }�(�<+B'r�m���FAj�j�J��-L�(2L�xC z

� A"2M3�$*�" %2' +$%�v�}2'�(#O��+<-��H�('�)�$*�)(: 02@(:+<�6- t �!�xw[z �j9l�(#T)��*��-D���C-'�)(:+.��-?�0' 20��-3l,-' +2 [�� !2%!3(*+.�6- t w����0z ��)-�2�AP�(�<(,�0 +$.��-�2 A�2M3�$*�" %23 %$%�v�.'K!'-�2L�(#$ 0-�(&�(�a)L�()� %$C�6-^)�$4��(: !2!(:+<�6- tv�(�!&mz� «F+ �Q\"�4(&$,�P�v��E� }� �Q>;�4(* %#{�"�C+9(&3T�83'+< %$&�0$*2M3'+<2/�(�x�.�"2M\"+<-��6�4(,$&�)(* %�(>f(:�6)�$4 +U� 0-�(;+<-�(: %$Q���/>6 +$*2' /�02��B> +#R<�$,��20 +� t i(y(z� Ax7-�M�v� *$4�oU0�(<P�B> A� !2%!�$4 �8)[ +$&�)(*+.-�� A;>;�4(* %# +�[��$4(%�W��- %�($,�Z>X��<;�4 !2!(Q:b��$*+< 0-�(: +2 3L�($Q2P�e�($* :�4�('%(H�e�($* ��)[ +$&�)(*+.-��|�Q>;�=(: %# 2' %�4+��6-��F(M�(���� %2S2%�()L�(<'+B�.+9(:+. +�%�}��-�2 -3�6-x:H\) %$4-' %�R@19oAN� 33+. %$,�($V:2M33+.2/�0�G�(<��=(&$&�)2!(:+<�6-D�n /��2M3����/>6 +$X'>��$,#S�(���Z> �,)� 020+9l, %2 t w/�?u � u��(�mz �J��-p +�[��$4(B(,3L�)(S�(�B�*�£�. +2 (*�

¸ 3!¹

Page 184: Practical Architectures for Survivable Systems and Networks (Phase

(,3' m+. +$&�($42M3'+.2%�(��«F +U� %�<��)�#$ 0-�(X@? !(&33�x2'�(�.���(>�� }«W@1¡ t �?u(�oz �o(&3' �A ����e�H589 �,)� 02!+<l,2%�)(:+<�6-����-���!��(�6 tvu����oz ���-P21���"(: !-�2' %2 }«W@ ��� }«W@1¡ t � �?u�z� 7.!��Q3;<?>j�v��+��4������(:+.��-O\� +$*-' +��� tv��u�0mz� A" /�0 �+. +� t 0�0 � w�0 0 � w i��0z �a'>��$W��2M3'+< +U"+.-P�1�A3'+B��3x:��0�,�,!P$&��-'2! S@19oAª« �G@ A��C+<(,3'��!3(W$4 %�"!'+B$*+.-P��)-">�(&$,!P�4(H�1��$4(,3'+.-' +�,�.'>��$-@19oA�+.-�(&3' �« �G@ AAU"+��X<L�0����-'2! %2{�(�Q�,!�$,��-'20 � EG33 %*$4��2@(:��$�: �m +!�#S��-'- 20��U� %$4(V:£2M3L�)-'-' %� :]'K$4 0 1@19oA ��@19a�R�0$*2M3'+9(: 02@(&!�$4 %�+�=�C+<(,3 -'�� 0-�2x:]!��* +$�V>;�4(: +# @19oAN�ª�('{2!�6-��*+B2' %$,�(<��< g)[�)(: 0-�(*+��(�1+.-�(: +$* %�=(7(:�;2L�/>��6+ZU6 !- (,3' �20��-�(*+.-"!' +2q�(<P�* 0-320 G�('� �8E{A{@19oA^�V>;�4(: +#S� tvu��!& � �xw��mz� 5 '> +� %�($,�Z>£�.$*+<(*+.-��(���<+.-�\��4 02+!�$*+9(H>��)-�2~$* +�.+��(<'+��<+<(H>(�a�,!'2M3��(�49l�(#S)P�*�6- +.- w i!&0y�t±w��!&�z �)-�2«F�(<��*�6- ��-P2ª7-��-�23 %����+.- w i 0��£tji � � �Pwou�z �F��-�2 �{ %!�#S��-'-£<� %�6+<-'-'+.-P�^�)(W�. %�(�4(�+<- w i �6i£tvu0y?� �umy�y � umy�� � u���u � u0y!�mz �r�<+��4(* %2G2M3�$4�6-'���<���6+.2%�(���Z>P¡[C� EG33 %$* +B�G��-� !-'��$,#$��!��J�(#/�(!'-�(H�('F!��* ['K!���+<-P'>��$,#S�)(*+.�6-/�6-5(&3' d %<�C d 6#$ 0-�(:+<�6-g3' +$* e�Q!��=(�R'> [� !��4 +'K!��l�*�(!�$*2! %�%C

98 02@(&!�$4 F-'��(* %�e'>��$ �m +!�#O�)-'-D�v� � �(��� w i6i�i 1m-3+BU6 +$,�4+<(H>/�('�@1�($V>x����-�2g�Q!�$QU"+ZU(�0<'+��<+<(H>B2!��!�$,�4 -'��(* %2?+.-^5})P)[ !-�2'+Z�A54²3�(*(,)D²����m�G�G�WCµ2+�,��C��Q$*+§Cj20�(#��)-3 %!�#S��-'-��m!�#S2�C�3�(&#T��

5�$* +)[��$=(C�6-��T«.587 N5 «F !-'+��(�[�(' A� %$VU�+<20 d �($,\"�,3'�()D²3�(*(,)��%² � �) +�4(&�+C�<P<'-DCj20��# �02��42%�6+ �02��%Cv)?> � �� @(�� � +��. : w�&0��� �(7C %)���$4( «F��A $4 %�< /�(�4   w C�2'�"2�

5�$* +)[��$=(C�6-��X�1��$Q\;�Q3'��)��6-��£-P�*+�23 %$ @�+��Q!��* 0²3�(*(,)D²����m�G�G� u Cj2%�,��C��Q$*+�Cµ2!��#���+.-��4+�2' +$V:H#$+��Q!��* ��

EG3' �6�.��<��(�l�£-�(* %$4-' !( *$*�o�4 02!(8$* %)���$=( �6- (,3' R$* +�.+��(<'+��<+<(H>g��-�2��* !2%!�$4+<(H>��('ª(&33 X�£-�(* %$4-' !(%�@1�/> u(���(� ²3�(*(,)D²����m�G�G�WC���+�)DCj��$,��

EG3' *$* %�4+�2' !-�(/�v�8�;��#T#$+��,�4+.�6-��6-��e$4+<(*+.2/�0���£-�(&$,�(�4(,$,!'2@(&!�$4 *$*�)(: 02@(:+<�6-D² � ��G�e� �¡3�(*(,)D²����m�G�G�WC�)�202!+�)DCv�6��U�

EG3' 4�e$*+9(:+.2%�(���£-x'K$&�(�=(&$,!32!(&!P$* �5}�,�Q!�$&�)-'20 ���/2! g���e�H5 �W¡[²3�(*(,)D²����m�G�G�WCµ2!+����PC��6��U�

EG3' �}�)(*+.�6-��(���£-P'K$,�(�4(,$,!'2@(&!�$4 *$4��(: !2!(:+<�6-��; 0-�(: +$R� � � ��G¡[²3�(*(,)D²����m�G�G�WCv'K<3+§Cv�6��U ��-'+�)�2���

EG3' � %2' +$&�(�l�;�(#S)�!�(: %$.�£-'2!+�2' !-�(}7C %�Q)[��-��* 4�J�()L�(<3+��.+9(H>�� � %2�e��7G�G¡ ²3�(*(,)D²����m�G�G�WCv'> +2'20+B$*20C��6��U ��

EG3' -' +���J�($*-3 %�6+< [:V@? %���<�6-A�£-��=(:+<(,!3(: 6'>��${A;!�$QU"+BU0�(<P�. A;>;�4(* %#T�R���G@��=A'A�¡�

EG3' 4�J�($*-3 %�6+< [:V@? %���<�6-{�;��#T)�!3(* %$.�*#/ +$,�6 !-'2+>{7C %�Q)[��-��* �E� %�(# ���J��7�E-¡[²3�(*(,)D²����m�G�G�WCµ2! %$=(/Cj��$,�Eo��+����B!��4(,$&�)(* (,3' 4'K$4 %�"!' 0-32+> ��-�2�23+BU6 +$,�4+<(H> �0'���-'-'��!3-'20 +2 U;!��<-' %$,�(<'+��<+<(*+. %�+�L'>�����<�o�C+<-���+B�8�g�<+��4(�('m(&3' 1�J��7�E 5}2PU"+B�*��$4+. %�$+.- (&33 �)L�0�4(T>6 /�0$%�e�C+9(&3p+.-'+9(:+��0�e2L�)(* ��0'8$* +�. %�(�* 0C � *�. %�(�* ?2M3' 02M\ (&33 �J��7�E d +<{�4+<(* '>��$;(,3' 8���)(: +�4(G$4 +U"+��4+.�6-��e�,!�<��4 %�"!' !-�({(:�I(,3' 82L��(: F-'�)(: %2^<� %�<�o�WC¢¡REG3' %$4 W�($* 8�(���4��"!L�($=(: %$Q�B>{�J��7�ESAx!�#T#O�0$*+. +�%C

¸ 3 3

Page 185: Practical Architectures for Survivable Systems and Networks (Phase

� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C � 0 � w�� g(!�� w i6i�i ²2+#S�Q2� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C �6i � w i g(!�� w i6i�i ²5 $,$,��>GA� %$VU�+<20 +�-23 +'r�(!��9(C20�6-�lL��!�$,�)(:+<�6-� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C w�� � ��� g(!�� w i6i�i ²�£-P�* 02+!�$* I«F +'r�0!��<(-�;��-3lL��!�$,�)(:+<�6-G�6-�7 ��� u A� +$QU� %$,�� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C w�w � w�� A� %) w i6i6i ²� ��!P$J �!��.-' +$&�(<3+��.+9(:+< %�n+.-�(&3' I�;��#T#$�6-^«F %�Q\�(*��)��D-?U"+�$4�6-�#$ 0-�(� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C wou � w�� A� %) w i6i6i ²�=!P�� +$ �8U� %$V�,��� +.-{�(#T2� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C w�� � w i �F2!( w i6i6i ²@{!��<(*+�)��<  �!��<-' %$,�(<'+��<+<(*+. %�1+.- d 1.: � E �«� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i : w/y � w�� �m��U w i6i�i ²@{!��<(*+�)��<  �!��<-' %$,�(<'+��<+<(*+. %�1+.- �e� � «� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C w�� � w�� «F 02 w i6i�i ²�=!P�� +$ �8U� %$V�,���.�m+<- A3A �«6�� %#$�6-^��-�2�7mAx587-� � u 9Z+B<�$&�0$Q>� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i C w�� � w/y «F 02 w i6i�i ²�=!P�� +$ �8U� %$V�,��� +.-�Ax!'- A����B�4(*+.20 }5}2�#$+.-vA;!'+<(* W«6�� %#$�6-A�&�02�#/+<-�2� �J��7�E 5 2PU"+��4��$Q>{�e5.: i6i : w�& � u�0 «F 02 w i6i6i ²«F !-'+��0�Z:£�0'�:=A� +$QU"+.2! Eo���(���� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : �xw � � g���- u(����� ²«F !-'+��0�Z:£�0'�:=A� +$QU"+.2! }«F [U6 %�<��)�#$ 0-�(&�� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : ��u � u � %< u(����� ²@��(�.+<20+.�(!�� -E-@19~E��0���-��#4<[ +2�2' %2?+.-��e�<+. 0-�( d %<�7{ +�"!' %�=(&�� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : �(� � u�� 5 )�$*+B� u(����� ²�;��-�(*+.-"!'+<-��S�;��#S)P$*��#$+��4 %�e�('�« �FAA�* +$QU� %$,�� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : �0y � y @1�/> u(���(� ²98��U6 �98 !(4(: +$ d ��$Q#� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : � � � wou @1�/> u(�(��� ²�{ !(,�*2/�0)[ �}�/U"+����)(:��$G�H#T)�$4��)[ +$,�Z>O ��(�<+�2L�)(* %�CA3AP9 A� +�,�*+<�6-��� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : ��� � w�& @1�/> u(�(��� ²@{!��<(*+�)��< �e!P�[ %$ �}U6 +$Q�,���.�m+.-�� %$,<� %$4���.5}!3(,3' 0-�(*+.2/��(: %2 A� +$QU"+.2! %�� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : � & � u0y @1�/> u(�(��� ²@?+.2%$4���*�0'%( � �$2! u0����� ²21-5�5�2!(*+BU� �� �;�6-�(&$*�(�a�£-'20��$Q$* !2!(&�Z>{@1�($Q\� +2��AP�0'> 8'>��${A�2+$*+B)3(:+<-����� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : ��0 � u�� @1�/> u(�(��� ²�£-320�6-��4+��=(: 0-�( d �0$*-'+<-��T@� %�Q�&�(�� %��+<- �m !(,�*2%�()[ � ��U"+B�?�)(:�($� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : ��i � ��� @1�/> u(�(��� ²� ���/�a+.- � � C � � +>�� 0-3 %$&��(:+.��-� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : w/� � � g(!'-' u(���(� ²�£-320�6-��4+��=(: 0-�( d �0$*-'+<-��T@� %�Q�&�(�� %��+<-^�£-�(* %$4-' !( ���x)��.��$4 %$� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : w(w � i g(!'-' u(���(� ²@{�HE�� %$Q<[ +$*���G �!��<-' %$,�(<��. F(*�T«F 0-'+��(�Z:b�('�:=A� +$QU"+.2! }5e(4(M��2M\"�� �J��7�E 5 2PU"+��4��$Q>{�e5.: u(�(��� : w�u � w i g(!'-3 u(�(��� ²

¸ 30º

Page 186: Practical Architectures for Survivable Systems and Networks (Phase

8�1(,$,�a5�2@(:+ZU6 ����;�6-�(,$*���a5 ���.���.�.98�"2/�(� � +��. +�;(:�Y<� ����� !2%!3(* %2

¸ 3 �

Page 187: Practical Architectures for Survivable Systems and Networks (Phase

� � � � � ��� �� � ���

t±w%z @ªCe5 <L�(2'+�C �F-XAP«�Ax�M�v�g�.+<-�\� +2©�.�"2/�0�m-L�0#/ ��,)L��2! %�+C �£-��=­:� �M¨M¨*�(®%�"&m¤�����¥ ¨��m¥ � ������#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ ���o�m¬����?¦(¥r®����P¤�� �m­:��¤ � �j�e)L�0�6 %� i 0 � w/� 0 ��7{�"2M\")[�($4(/�G@1�(�,�,��2M3"!��* @(*(,�%�g(!'-' w i6i!& Ctvumz @ªCP5 <L�(2'+N��-�2g5IC¢«RC � ��$,2'��-DCa5S2/�0�.2%!P��!���'>��$;2+$Q>;)3(*����$&�0)�3'+.2 )�$*�)(:�"20���B�%²�EG33 �Ax)'+�2/�(�<2%!��B!��%CE� !2M3'-'+.2%�(�6$* +)[�($4(/� «F+���+<(M�0�}�*�"!'+�)P#/ !-�(��;�($,)���$&�)(*+.�6-���Ax7G� 7C %�4 /�($42M3 7C %)���$4( w%y�i � ��(�<�5}�<(*����J�(�<+B'>��$4-'+��x�3g��)-;!��($Q> w i6i 0 Ct �0z @ªCG5}<L�02'+���-�2�9�CJ9F�0#S)���$4(%C �;��#T)[���4+.-����Q)[ !20+<l'2/�)(*+.�6-��+C �£-SgPC d CG2' �J�(\"\� +$%� d C : �C2' {7{�" +U� %$%�=��-�2 �XC�7C���0 !-;<� %$Q���; +2'+<(*��$,�+� �¥�¨ ���*®�¤�¨��-¨��D��¨@�O¨@�L¥k�����W®�¤[¥�­ ® %¬;¥�¨*� ���o¤[¥H¨@�4¤��� �0�;¨[¯¢¤������m­±�T¦(¯±®�¤@�4¤���#1�m­ ­M¨��[¥u��¨M¤M¤[�e)��(�6 %� w � y�w �J7-� � d ��$,\"�,33��)D�-@��"��\�JEG3' �{ !(,3' %$�:����-�2P�%�.@1�/>?:=g(!3-' w i 0�i C1Ax)�$*+<-��6 +$V:] D +$,���(��� �1 %$,�<+.-D�e98 02!(,!�$* �m��(* %��+<-©�;�(#S)�!�(: %$5A�20+< 0-'2!  D���§C u0��� C

t y(z @ªCa5}<L�02'+*��-�2 �XC�7�C¢@ªCa98 0+<-'��CR5 �<���6+<2k�('1��<;�4 !2!(Q:b��$*+< 0-�(: +2£)�$*���($&�(#T�%CIE� !2M3'-'+.2%�(�*$* +)[�($4(/��;��#S)��(��A;>;�=(: %#T�I7{ +�* /�0$*2M3��; 0-�(: +$%��AP7G��7C %�4 /�($42M3~7C %)���$4( w �Pw �/��0�.�A5}�9(:���F�J�0�.+B'>�($*-'+��P�A� %)3(* %#R<� %$ w i�i 0 Ct �mz @ªCP5 <L�(2'+a�)-�2^7�C �m ! %2�3L�0#�C �$Q!�2' !-�(C !-��6+<-' 0 +$*+.-P�X)�$&��2@(:+<20 '>�($e2%$V>x)�(:����$,�()�3'+<28)�$4��(:�"20���B�%C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��������� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� u�u � w ¡ ² � � w�� �,g��)-;!��($Q> w i6i � Ct �0z IC5}<� %�B�*�6-D�7WC5�-�23 %$,�4�6-D��ANC¢@ªC �; %�B�.��U"+.-D�vgPC �; !-L�(�<��3D�j@ªC �e���(�0 0� d CN«F+ �$ (��gPC ��+B��#$��$* 0��C �YC��{ %!�#S��-'-D�(7�C�9*Co7{+ZU6 +�4(/�6gPC��MC)A�2M33+����< %$+�0�)-�2 � C�A"2M3'-' 0+< %$+C;EG33 =$4+��,\"�o�('�\) +>�$* !20��U6 +$Q>(��\� [> %�*2+$*���W�j��-�2�(&$Q!��4(* %2?(&3'+B$,2x:])L�($4(H>/ 0-32%$Q>;)3(*+.�6-�C�� �m­ ¯9���A®u�;¨ ��¨ �!,�m¬;­±�j¦(¯#"$��¨ �D¨��[¬;­ ®°¥��%�� � ¦(¥�¥H¨[­B��� ­ ¬"¤[¥'&m� u � � ¡[² u0y�w � u � & �'Ax!�#T#/ +$ w i6i!& C�EG3'+��.$4 %)���$4(.�e�(�HlL$,�=( 23+��4(,$*+B<�!3(: +2{U"+��(&3' W�£-�(: +$*-' @(��6-�@1�/> u & � w i6i!& C

t &mz IC5}<� %�B�*�6-D�7WC5�-�23 %$,�4�6-D��ANC¢@ªC �; %�B�.��U"+.-D�vgPC �; !-L�(�<��3D�j@ªC �e���(�0 0� d CN«F+ �$ (��gPC ��+B��#$��$* 0��C �YC �m %!P#O��-3-D�D7WC¢9*C�7{+ZU6 %�=(/�ZgPCv�MC8A"2M3'+��B�. %$+���)-�2��}C8A"2M3'-' 0+< %$+C6EG3' X$*+B�,\"�F�('�\� [>�$4 020��U� %$Q>(�\� +>x +�*2%$4���W����-�2 (,$,!��=(: +2 (&33+�$,2;:H)L�($=(H>� 0-'2+$Q>;)3(*+.�6-DC ¥�¥ �(�*)+)��ª�ª�n�u�*�(¥b�u�m­h&,)8�[­ � �j¥\��)j­ ®�¤���¤�-/.0)j�g(!'-' w i�i 0 ClEG3'+��1+��e�4$* !+��,�Q!' F�('�(&3' W@���> u & � w i6i & $* +)[�($4(/�;�C+<(,3A�k-' [��)P$* +'r�)20 F [U(�0��!L�)(*+.-���.3L�)(-3L�()�)� 0-3 %2 +<-5(&3' �+<-�(* %$VU6 0-3+.-��Y>6 %�($%C

t 00z �}CG5}�B)[ +$*-���-�2 � C � CCA�2M3'-' !+�2' +$%C�«F !l,-'+<-����.+ZU6 0-3 %�,�+C �1� �m­±�T¦(¥�®����2�=­�� �M¨M¤M¤[®%�"&�3l¨[¥�¥H¨[­&¤[�uxw � y ¡[² w�0Pw � w 0!� � � 2@(:��<� %$ w i�0!� C

t i0z gPCP5}�ZU6 +�V: � ���Q�%C�EG3' 6!��* �0'l<[ +�.+. ['a�.�(�6+.2+�;+.-/(&3' 8)P$* %�4 0-'2! ��('Z2/�(!P�&�(��2!�6-��4+��4(* 0-'2[>A�)(4(M��2M\"�+C��£-�e­:� �M¨M¨*�(®%�"&m¤���� ¥ ¨548®%��¨[¥H¨M¨@�L¥ 46¦(¥�®����j¦(¯�#1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ �G#1���1�/¨[­M¨@���M¨[�?)��(�6 %� y?� � � y�w�& ��J�(�<(*+�#$��$* 0��@��($Q>;���)-�2D� � � w�� � 2@(:��<� %$ w i�i!& C �-�=AxE ���}�HA��}C

¸ 3 �

Page 188: Practical Architectures for Survivable Systems and Networks (Phase

t±w��0z �.C�5}#$��$*���4��C �L¥r­ ¬"¤[®�����R¨[¥H¨��[¥�®���� ����� �L¥�­:�0�(¬,�[¥�®����ª¥\� �L¥H¨[­@��¨[¥ �¬;­��(¨[®°¯°¯Z¦����M¨���#1�m­ ­&¨[¯Z¦ �¥�®����3� ­,¦"�M¨�� ¦"��� � ­,¦ �L¤���¦���� �.¨M¤ �,���P¤�¨[C��£-�(&$,!P�*+.��-DC �{ !( �;�"��\"�%� w i6i�i Ct±w�w%z «RCN5m-�2' %$Q�*�6-��DE6C � $*+ZU6���B2D�j��-�2�5ICj ��(�B2' %�+C �{ [�"(Q:]�6 0-' +$&�)(*+.�6-1�£-�(,$,!��4+.�6-;:�«F !(* 02@(:+.��-����P)� %$=(A;>;�4(: +# � � ��«6�nA�¡ CeEo 02M3'-3+.2/�0�F$4 %)���$4(%�N�;��#S)P!3(: +$�A"20+. !-'20 I9l�(<���$&�)(*��$Q>(��AP7.�e�£-�(: +$*-L�)(*+.�6-��(�§�@� 0-��<����($Q\j�N�J�(�<+B'>��$4-'+��x�3Ax7-�§:��HAP9�: i!� : �!& ��@1�/> w i6i!� Ct±woumz «RC�5�-P2' %$Q�*�6-D�lE6Ca9a!'-�(%� ICZg��/U"+<(,�(�D5ICDE��0#O�($Q!D�a��-P2�54C� ��(�B2' %�+CIAx�0'> %��!��($,2 l,-��(��$* +)[�($4(/²«F !(: !2!(*+.-�� !'-"!��,!L�0�P)�$4����$&�0#�<[ +3L�/U�+<��$�!P�*+.-P�m(&33 � ��«6�nAI�=(M�)(*+��=(:+.2%�(��20��#T)��6-' 0-�(%CxEo 02M3'-3+.2/�0�$* %)���$=(/�G�;�(#S)�!�(: %$�A�2!+. 0-320 �9F�0<[��$,�)(:�($Q>��eAP7.�4�£-�(: +$*-L�)(*+.�6-��(�§�e@� 0-P�.� ��($,\�.�J�0�.+B'>�($*-'+��P� u«F 020 +#R<� %$ w i6i�� Ct±w��0z gPC FC�5�-�23 %$,�4�6-DC��;�(#S)�!�(: %$G�4 02+!�$*+9(H>�(: !2M3'-'���<���(>S)����)-'-'+.-P�R�4(,!�2P>�C�E� !2M3'-'+.2%�(�l7C %)���$4(J�1Ax« :E.7G: &(� : �;w � 1�CEANCP5�+�$ � �($*20 W�*�< 02!(,$*�6-3+.2 A;>;�4(* %#T�-«F+BU"+��4+.�6-D� �F2!(*��<[ +$ w i!&�u C.�rEJ�1�TU�����!P#/ +�M¡[Ct±w/y(z @ªC�5�-�23 %$,�4�6-D�(�}C��m��$=(&3D�)gPC �6$*+ �$-D�)gPC �n %�Q<[ +$,���0��-�2 �XC � +B!DC�A"(&�($,�<+���3�(%²��£-�(: +$&��2@(:+BU� ��.+.-P\jC0�£-�e­:� �M¨M¨*�(®%�"&m¤B���I¥ ¨ �e¨[¯ � ¥ ���,�L¬�¦(¯n#1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ �7� � �j¯±®��,¦(¥�®����P¤�#1���1�/¨[­&¨@���M¨[�L)L�(�6 +�

� � � ��� �vAP��-{«F+. +�6�����J�(�.+Z'>��$*-'+��P�x«F 020 +#R<� %$ w i6i � C��������©�;��#S)P!3(: +$�A"��2!+. !(H>(Ct±w��mz 7�C?5m-�2' %$Q�*�6-O��-�2g@ªC �6!�3'-DCa98���L2!���4(e�)(4(M��2M\"�n�6-$(&�(#T)[ +$*$* %�4+��=(M��-�(=2' +U"+.2! %�+CD�£- � �j­ ®%�"&;¨[­ �

� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� �D¨��[¬;­ ®°¥�� �=­��m¥£� ���m¯¢¤��#�=­:� �M¨M¨*�(®%�"&m¤k���� ¥ �L¥�¨[­±�j¦(¥r®����j¦(¯ � �m­:��¤ � �j��)��(�6 %� wou�� � w�� � � ��0$*+��+� � $&��-320 (�L5 )�$*+B� w i6i & C

t±w��0z 7�C IC*5m-�2' %$Q�*�6-�C�5 �Q#$+.-'+B#R!�# %�Q�* !-�(*+��(�C+<-P'>��$,#S�)(*+.�6- +.-P'K$,�(�4(,$,!'2@(&!�$4 %�q�§@1�*�,�V¡4'>��$ 1�CEAjC2' +'> !-��* £�Q>;�=(: %#T�%²�@� /��-3+.-��('K!P� � '> /�0�*+�<P�. � !P�* +'K!P� � �£- �C��¤[®°¥r®���� �J¦ �L¨[­&¤ � �m­�¥ ¨�+-+-/. �1� �m­±�T¦(¥�®���� �¬x­���® �m¦%®°¯±®°¥ �� �m­���¤ � ��� � � � -/.��")L�0�6 %� w�w � w/y � �8$,����-�2'��� � �.��$4+�2L�P� u�0 � �(�� 2@(:��<� %$ w i�i 0 CP�������GC

t±w�&mz E6Ca5�-�2' +$,�4�6-~��-P2PgPC¢�}C � -'+���3�(%CX5 'K$,�(#$ +�1��$,\{'>��$6�*�('%(H�e�($4 T'r�(!P�<(F(*���. +$&��-'2! 7+.-£$* %�(�Z:�(:+�#$ �Q>;�4(* %#T�%C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��������� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(�vAP��: i � � ¡ ² � � � � � �0y ��@���> w i 0�� Ct±w�00z E6C�5�-P2' %$Q�*�6-|��-�2�FC�5IC�98 0 0C �l¦(¬;¯±¥ � �m¯�¨[­Q¦����M¨�� �=­ ®%���[® �j¯�¨M¤g¦���� �e­Q¦"�[¥r®��M¨[C *$* !-�(*+.2! [: �(����£-�(* %$4-L�)(:+<�6-L�(�����ª-����< +�1���;21�e�.+B�N�%� �m [� g� %$Q�* +>(� w i 0Pw Ct±w i0z d C�5ICm5 $,<L�0!���3D�6gPC¢7WCm«6��U"+<-D�m«RCEgPC � �($,<� %$+�(�)-�2IgPC¢@ªC�Ax#$+<(&3�C�A� 02+!�$*+9(H>W'>��$l)�$*+ZU(��(: D+.-�(&$,��-' @(&�%C ������ #1��� �j¬;¥H¨[­[� �Pw � i ¡[² y!0 � � � � w i6i�0 CDAx)� 02!+��(�8+B�,�,!3 ��-{<P$*�?�(2P<L��-�2?-' !(H�1��$Q\"+<-��T�* 02+!�$*+9(H>�Ctvu(�0z d C�5ICD5}$Q<L�(!���3��l«RCEgPC � �0$,<� %$%�l�)-�2xgPC @ CoAx#/+9(&3DCW5 �4 02+!�$* S��-�2�$4 %�.+��(<��< 4<�����(,�4(,$&�()£�($42M3'+Z:(: 02@(&!�$4 (C��£-�e­:� �M¨M¨*�(®%�"&m¤f���6¥ ¨ +-+- ���)� �,��¤[®°¬"� �����D¨��[¬;­ ®°¥��O¦���� �=­ ® �m¦"���0��)��(�6 %� �!� � &xw �

�W�0\;����-�2D�L�J�(�.+Z'>��$*-'+��P�P@1�/> w i6i!& C�������� �;�(#S)�!�(: %${A"��2!+. !(H>(Ctvuxw%z d C�5ICx5 $,<L�(!P��3D�;54C�«RC � +$*��#4>�(*+��%�;«RC°gPC � �0$,<� %$%�x��-�25gPC @ C'Ax#$+<(,3DCD5 !3(:��#S�)(* %2T$* 02!��U6 %$V>5+<-�W�4 02+!�$* -<[�"��(,�4(&$,�()X)�$4��2! %�,�+C��£- �=­:� �M¨M¨*�(®%�"&m¤F���G¥ ¨ +-+-/. 4I¨[¥u�;�m­:�4¦���� �W®�¤[¥r­ ® %¬x¥H¨*� ���o¤[¥H¨@�

�D¨��[¬x­ ®°¥ � ����� �,��¤[®°¬��X�,AP��-�«F+. %�����L�J�(�<+B'>��$4-'+��x��@1�0$*2M3 w i6i 0 CP�£-�(* %$4-' !(FA��"20+. @(H>�Ctvu�umz 54CP5 $*��$,�X��-�2�ANC°ANC �6!��B\0�0$*-'+�C��;�(#S)��6-' !-�(J<L�(�* +2�23 %�*+B�6-��('F#R!��9(:+9(:���< %$&�)-'20 0C ������ ­Q¦��P¤ �¦"�[¥�®����P¤I��� ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� u0y � w ¡[² ��� � &�0 �,g��)-;!��($Q> w i6i 0 C

¸:º �

Page 189: Practical Architectures for Survivable Systems and Networks (Phase

tvu(�0z 54C�5}$*�($&���)-�2 ANC°ANC �6!���\m�($4-'+§C «F @(: !2!(:�($,�g�)-�2 2!��$,$4 02!(*��$,�+²�5 (,3' 0��$V>p�('8'r�(!��9(Q:�(:���< %$&�)-'20 20��#T)[��-' 0-�(&�+C��£- �=­:� �M¨M¨*�(®%�"&m¤f���}¥ ¨ � ®9& ¥�¨M¨@�L¥ � �L¥�¨[­±�j¦(¥r®����j¦(¯�#1���1�/¨[­&¨@���M¨���� �W®�¤[¥r­ ® %¬x¥H¨*�#1��� �j¬x¥r®%�"& ����¤[¥�¨@�4¤[CL������� �;��#T)�!3(* %$mA��"20+. @(H>��j@1�/> w i6i 0 Ctvu0y(z gPC �J��20��-DC©7C %)���$4($�6- (&33 1�ª+��(3�(,3�5-�G@ Ax� � � nA���!P$*��)� /��- d �($,\"�,3'�()D�CA;>;�4(* %# Ax!�);:)[��$=( '>�($}�;�(#S)����*+<-��S«F+��4(,$*+B<�!3(: +2�5 )�)��<+.2/��(:+.��-��%C ���L¨[­Q¦(¥r®%�"& ���o¤[¥H¨@�4¤ �-¨���®§¨@�*� ��� � w ¡ ² � � w�& �g���-"!L�($Q> w i6i6i Ctvu �mz «RC �J�(�B'r�)-��(�«RCj«F /�)-D���-�2�@ªC[Ax)�$* !+<(,�0 %$+CJ5 �* 02+!�$*+9(H>?+.-P'K$,�(�4(,$,!'2@(&!�$4 �'>��$.2'+B�4(,$*+�<P!3(: +2 g��/U0��()�)��<+.2/��(:+.��-��%Cg�£-��e­:� �M¨M¨*�(®%�"&m¤����T¥ ¨ � �+�+� ����� �,��¤[®°¬�� ��� �D¨��[¬;­[®°¥ ��¦���� �=­ ® �m¦"���0��)L�(�6 +�

w�� � u�� � �6�(\"����-�2���J�(�.+Z'>��$*-3+��P�x@1�/> u(���(� CP������� �;��#T)�!3(: +$mA���2!+. @(H>�Ctvu��0z � C �e�����G7WC �Ce«F !-���� �RC ��-D�G54C;g� 0-P���G54C�«RC � �($&�0�*+�#T3L�(�B!D�=��-�2©E6C � �?��+B$%C �e$4 /�(\�+<-��)�!�<��<+.2�\� [>f2+$Q>;)3(*���Q>;�4(* %#T� �6- (M�(#T)[ +$l$* %�4+��=(M��-�(�2' +U"+.2! %��+.-�(&3' �)�$* +�* !-'20 e�0''(&$,��-��*+< 0-�(F'r�(!��<(,�%C�£- � �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �}¨[­[¯±®%�3� 3F¨��[¥r¬;­M¨ 4 �m¥�¨M¤1®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� �D¨��[¬x­ ®°¥ � �=­��m¥£� ���m¯¢¤��

�e­:� �M¨M¨*�(®%�"&m¤���� � ¥ �L¥H¨[­±�j¦(¥�®����j¦(¯ � �m­���¤ � �j�;)L�(�� %� w(w�� w�u(� ����0$*+��+� � $,��-'20 0�P5 )�$*+B� w i6i!& Ctvu &mz �C �J�($&�)-DC}7C %�<+��(<P�. W2'+���+<(M�0�820��#T#R!'-'+<2/�)(*+.�6-P�-�V>;�4(: +#S�}!��*+<-��g!'-�$4 %�<+��(<��< �-' !(H�1��$,\{$* +)[ %�)(: +$-'�x23 %�%C�Eo 02M3'-3+.2/�0��7C %)���$=( �: w i6i!� �PEG3' I7-5��}«��;��$,)���$,�)(:�6-��@1�/> u &gw i ��� Ctvu�00z gPC �J�0$&�($4 %���<�O�)-�2 d C ���0�*+��)-DC�1{-'+<(* %2�A�(M�)(* %�}5 $,#4>1�;��#T#$ %$*2!+��(���}�:HEG3' :=Ax3' +�B'-��� �8E{A�¡ [�x)[ +$*+< 0-'2! (²TEG3' A)�$*�(#/+B�* %�I��-�2�$4 /�(�<+<(*+. %�+C^�£- �e­:� �M¨M¨*�(®%�"&m¤G���T¥ ¨�4H� � #1���1�/¨[­&¨@���M¨����#1���B�O¨[­��[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤I®%� �R¨ �/¨@���M¨{� � �j¯±®��,¦(¥�®����P¤�� � ¨ �G¬x¥ ¯�¨M¤M¤ �=¬x­&¤[¬;®°¥{���# � �� �e$,!P�,�* +���+� �; %�B�6+�!�#{�P5 )�$*+B� u(���(� C � 5*E �RCtvu�i0z 54C �J�($4-' %�+�54C m���B�B�e�/>��L��-P2 FC �XC��m +!�#O�)-'-DC;Ax!�$QU"+ZU(�0<��. �20�(#S)�!�(: %$�:£2!��#S#4!'-'+.2%�)(:+<�6-g�V>x��:(: %#T�%²�EG3' )P$*��<��< %# �)-�2S�1��$,\�+<-��4��$4��!�)T$* !20��#T#/ !-�2L�)(*+.�6-P�%C� �589�:V�J��:HE.7J: i�u : u�u �K$* +U"+B�*+.��-w ¡[C�Eo 02M3'-3+.2/�0�-$4 %)���$4(%� 1�CEAjC*5}$,#I>�7{ +�* %�($*2M3q9F�0<[��$,�)(:�($Q>���58@ AP7-9D:\AP9�:��G� d 3'+9(: ?AP��-P2��@�+��Q�*+��< W7 �)-��6 (� �8@ 0 0����?u : � �xw/� ��@���> w i6i�� C � ��$ ���$20+��(� 1-�* �F-��B>(Ct ���0z 7�C°ANC �e�($4(*�6-DC�5 2+$*+9(:+.2%�(��$* +U"+< +� �('C(&3' O�4(M��(: 5�('H(,3' A)�$4����$&�0#S#$+.-����($=(/C��£- �=­:� �M¨M¨*�(®%�"&m¤���4¥ ¨ � �j­ ®%�"& !v�m®%�L¥�#1��� �j¬;¥H¨[­5#1���1�/¨[­&¨@���M¨[�jU�����!P#/ u(� ��)��(�6 %� w��6i � w�& & ��@��6-�(,U0�(�< (� �{ +�g� %$,�4 +>(��@���> w i ��� Cx5 � � nA �$4 %�Q�%Ct �Pw%z 9�C��J�(�Q�%� FC��e�< %#$ 0-�(&�+����-P2�7�C �W�(�%#S��-DC ����� ¥u��¦(­&¨I�}­�� ®°¥H¨��[¥r¬x­&¨S®%���e­Q¦"�[¥r®��M¨[C^5}2�2'+B�*�6-;:d +�,�. [>��7C /�(23+.-����L@1�(�,�,��2M3"!��* @(*(,�%� w i6i 0 Ct �?umz «RC¢�GC �; +���.��-�2�9*CEgPC�9l� ��(2P!����PC A� !2%!�$4 2!��#S)P!3(: +$T�V>;�4(: +#S�{²^5 #S�)(,3' %#S�)(:+<2/�(��#$�x2' +�§CE� !2M3'-'+.2%�(�D7C %)���$=(G@�E.7J: u��0y�&  D�(�§C?�,�M�P@�+9(&$* }�;��$Q)[��$,�)(:+<�6-D� �; +2P'>��$,2���@1�0�,�&�)2M3;!P�* !(4(&�+��@���>w i!&(� Ct ���0z «RC¢�GC �; %�B����-P2�9*CEgPCN9l� ��02�!����xC A� !2%!�$4 I20��#T)�!3(* %$ �Q>;�4(* %#T�R²G5�$4 !l,-' +#/ !-�( �('ª(&33 4#S�)(&3x: %#S�)(:+<2/�(�=#/�;2' %��C£E� !2M3'-'+.2%�(�.7C %)���$4(T@{E.7G: u �0y�&  D����C��Q�,�M��@�+9(&$4 {�;��$,)���$&��(:+.��-D� �; %2x'>��$,2D�@1�(�,�,��2M3"!��* @(*(,�%�D«F !20 +#R<[ +$ w i!&(� Ct �(y(z «RC¢�GC �; %�B�l��-�219�C°gPCj9l� ��(2�!����PCHA� !2%!�$4 k2!��#S)P!3(: +$ �V>x�=(: +#S�I²G@1�)(,3' %#S�)(*+.2/�0��'>��!'-�2��)(:+<�6-��%CE� !2M3'-'+.2%�(�x7{ +)[��$=(*@{E.7G: u �0y�&  D���§C��M�0@�+9(&$4 J�;��$Q)[�($&�)(*+.�6-D� �; +2P'>��$,2��?@1�(�Q�&��2M3"!��4 !(4(&�%�x@1�0$*2M3w i!&(� C

¸:º ¸

Page 190: Practical Architectures for Survivable Systems and Networks (Phase

t �!�mz «RC¢�GC �; +���?�)-�249*C°gPC�9l� ��(2�!P���PC6A� 02+!�$* n20��#T)�!3(* %$a�V>x�=(: +#S�+²�@1��(&3' +#O�)(*+.2%�(�0'>��!3-�2L�)(*+.�6-��l�)-�2#/�;2' %��CSEo 02M33-'+.2%�(�e7C %)���$=(R@ &0y : umy�y �lEG3' A@?+<(&$4 S�;��$,)���$&��(:+.��-D� �; %2P'>�($,2D��@1�(�,�,��2M3"!��* @(*(,�%�@1�/> w i!&(� Ct � �0z «RC¢�GC �1 %���x��-�2Y9*C°gPC�9l� ��02�!����xCvA� 02+!�$* H2!��#T)�!3(: +$��Q>;�=(: %#{² 1{-'+<l' %2B [�x)����*+9(:+<�6-X��-�2X@�!��<(*+.2+�+.-�(: +$,)�$4 !(M��(:+.��-DC E� !2M3'-'+.2%�(� 7{ +)[��$=(A�nAP« :]E.7G: & � : �(� � ��EG3' £@�+9(&$* 1�;��$Q)[��$,�)(:+<�6-D� �1 %2P'>��$Q2@1�(�,�,��2M3"!��* @(*(,�%�a@��($*2M3 w i!&�� Ct �!&mz ANC @ C �; %�B�.��U"+.-DC � ¨[­[® �=¦%¯ �7#1�m­ ­&¨��[¥1#1�0�;¨�� ¨@��¨[­Q¦(¥�®������a¤[®%�"& �=­&¨*�(®��,¦(¥H¨ ­Q¦��P¤ � �m­±�O¨[­&¤[C *3L«(&3' +�*+��+�L«F %)��($4(,#/ !-�(;�('��;��#T)�!3(* %$CA�2!+. !-'20 0� 1m-'+ZU6 +$,�*+9(H>5�(')�{��$4(,3{�J�($*�(�.+.-��4�)(G�e3L�()� %�� {+��B�§�«F 020 +#R<� %$ w i 0?u C�3�(*(&)�²�� �o�G�G�WC�$4 %�* %�($*2M3�C¢�)(4(/Cj20��# ���/�Q#R<��023+��,�,�(<��=(&$&�)2!(/Cv3�(&#T�§Ct � 00z ANC @ C �; %�B�.��U"+.-DC *$*��<L�0<��. g)P����+<-�(* [�"(I2+$Q>;)3(&��-L�(�Z>x�4+��I�0'H(&3' A� �)�$*�)(:�"20���B�%C��£- �=­:� �M¨M¨*�(®%�"&m¤���W¥ ¨ ����� �,��¤[®°¬�� ��� 4�¨[¥h�;�m­:�O¦������W®�¤[¥r­ ® %¬x¥H¨*� ����¤[¥�¨@� �D¨��[¬;­[®°¥ �m�j)��(�6 %� ��u � ��i CL�£-�(: +$*-' @(A���2!+. @(H>�� � %<�$Q!L�($V> w i6i!& Ct �6i0z ANC @ C �1 %���<��U�+<-{��-�2�@ C�@? %$,$4+<(4(/CJ98+B#/+9(M�)(*+.�6-��1�('�(,3' �� +$,<� %$4���}�0!3(&3' !-�(:+.2%�)(:+<�6-^�Q>;�4(* %#{CG�£-

� � � 4 �� #1���1�/¨[­&¨@���M¨��=­:� �M¨M¨*�(®%�"&m¤�� �A®%�L¥H¨[­ � -+(�Zg���-"!L�($V> w i6ixw C65�U6 +$,�4+.�6-��('D(&33+��8)L�0)[ +$�()�)� /�($4 %2?+.-p#1��� �j¬x¥H¨[­7#1���B�X¬"�L®��,¦(¥�®����P¤ �.¨���®§¨@��� �F2!(*��<[ +$ w i6i�� Ct y?�0z 9�Cv54C �; 0-��!+.-��� %$%� �XC d CD«F+.-'���9(/�a�)-�2ª@ªC �XC �=�)(&�(<� (C � +<-L�(��$* %)���$=(/²65 2'+B�4(&$4+�<�!�(: %2£�V>x�=(: +##R!��<(*+�)��< .�* 02+!�$*+9(H>g)����.+<2+>T#$�x2' +�§ClEo 02M3'-'+<2/�(��$* %)���$=(/��98��$,�(� d +�4(: +$*-{«F +U� %�<��)�#$ 0-�(.9l�(<���$&�m:(:��$4+. %�+��$* +)[�($4( d «69�:HE.7 ���!& & & �,AP��-�g����4 (�N�J�(�<+B'>��$4-'+��P� �F2!(*��<� %$ w i6i(y Ct y�w%z ANC �; +$,\���U"+<(,�%�egPC¢«RC �6!3(4(&#S��-D����-�2� RCªA;�J�0$,!�)DC�5 !3(&3' !-�(:+.2%�)(:+<�6-~'>��$X#$��<'+B�. g�0�6 0-�(&�+C��£-

� �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤I®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��1&;¨@�L¥°¤R¦�����D¨��[¬x­ ®°¥ �0�L)L�0�6 %� w�w/y � w�� � � w i6i 0 C

t y"umz �YC°gPC �;+B<L�PC��£-�(: +��$*+9(H> 20�6-��4+�2' +$&�)(*+.�6-P�R'>��$X�* !2%!�$4 20�(#S)�!�(: %$Y�V>x�=(: +#S�+C�Eo 02M3'-3+.2/�0� 7C %)���$=(@�E.7 �Pw��0� ��EG3' @�+9(&$* G�;��$,)���$&��(:+.��-D� �; +2P'>��$,2��;@1�(�,�,��2M3"!��* @(*(,�%�,g(!3-' w i!& � CP5}���4�W�/U(�)+����0<��. 'K$*��# 1FAx5 � ���< 02@(&$*��-'+.2 A;>;�=(: %#T�-«F+BU"+��4+.�6-�� �1 %2P'>��$Q2D�j@1�(�Q�&��2M3"!��4 !(4(&�%�N�(�.�nAP« :]E.7G: &�� : � &�u �5})�$4+�� w i & & Ct y?�0z �YC �C �1+�$,#S��-���-P2�E6Cv54C1g����4 %)�3DC�7C %�.+��(<��< 520��#T#R!'-3+.2/��(:+.��-P+.- (&33 �)�$4 %�4 0-'2! �('-'r��+��B!�$* +�%C�I# � ­,¦��P¤%¦"�[¥r®����P¤k���P#1��� �j¬x¥H¨[­ ���o¤[¥H¨@�4¤[� � � w ¡[² y�& � & � � � %<P$,!L�($V> w i 0 & Ct y�y(z @ªC �e���(!�#{�ªgPC �e$,!'2M\� �XC�7.!�<'+<-D�*��-P2 d C�98 0-�(&3�C�5 20�;2'+.-P���()�)�$4�?��2M3~'>��$I2' !(* 02@(:+.��-P�('(M�(#T)[ +$*+<-��F+.-R�.$4+<(* [:£��-'20 H��)�(:+.2%�(�P23+��,\"�+C ������ ­Q¦��P¤%¦"�[¥r®����P¤�����#1��� �j¬;¥H¨[­M¤[�;��: y�& � w ¡[² wou(� �wou � �vg��)-;!��($Q> w i6i 0 Ct y��mz @ªC �e��!�#$ (C�}®§¨[­,¦(­:� ®��,¦(¯ � �0�(¬x¯Z¦(­ ®°¥ �A¦���� �L¥H¨[­±���0�(¬x¯�¨ ���j¥�®%�X® ��¦(¥r®����LC *3L« (&3' +�*+��+�N�;��#Y:)�!3(: +$mA�20+< 0-'2! 4«F +)L�($4(,#/ !-�(/� *$*+<-'20 @(:�6-%1m-3+BU6 +$,�4+<(H>����{��U6 %#4<[ +$ w i�i!& Ct y!�0z 54C�«RC �e��!P#/ !-��4(*+. %��C A" 02%!P$*+<(H>g�(�,�4 %�Q�,#$ 0-�(�2!�6-��4+�2' +$&�)(*+.�6-��J'>�($J58«69£58« |�Q>;�4(* %#T�%C�E� !2M3'-'+ :2/�(�$* +)[�($4(/� 1�CEANC;«F +)L�($4(,#/ !-�(1�0'aE�$,��-��Q)[��$=(M�)(*+.�6- �(7�A N5 �o D����)� .�; 0-�(* %$%���J�(#R<�$4+�2��� (�x@1�(��:�&��2M3"!��4 !(*(,�%� w i 0!� Ct y�&mz 54C�«RC �e�B!�#/ !-��4(*+. +�§C � 5}5 2!��#S)P!3(: +$X�* 02+!�$*+9(H>P2%��-�2'+B2L�)(: �20��!'-�(* %$,#$ /�0�,!�$4 %�X'>��$I +�. 02@(&$4�6-'+.2)[ !-' !(,$&�)(*+.�6-N�('A58« �V>x�=(: +#S�+C Eo 02M3'-'+<2/�(�S$* +)[��$=(/� 1IC°ANCI«F %)L�($=(&#$ 0-�( �('AEF$&��-��Q)[�($4(M�o:(:+.��-��(7mA N5 �m D����)� W�; !-�(* %$+���J�0#R<�$*+B2��6 0�@1�(�Q�&��2M3"!��4 !(*(,�%� w i 0 � C

¸:º

Page 191: Practical Architectures for Survivable Systems and Networks (Phase

t y!00z 54C�«RC �e�B!�#/ !-��4(*+. +�§C ��)(: 0-�(*+��(�120�6-��4 %�"!' !-'20 +���(' ��-�2 2!��!'-�(: +$,#$ /�(�Q!�$* +�T'>�($R�(2PU0��-320 %2��(!x:(:��#S�)(:+<�6-^�Q>;�4(* %# %�< 02!(,$*�6-3+.2�)[ !-' !(,$&�)(*+.�6-DCGEo 02M33-'+.2%�(��$4 %)���$4(%� 1IC°ANC�«F +)L�($=(&#$ 0-�(��0'*E�$,��-���:)[��$=(M�)(*+.�6- �(7�A N5 �o D����)� 6�; !-�(* %$+���J�0#R<�$*+B2��6 0�@1�(�Q�&��2M3"!��4 !(*(,�%� w i 0 � Ct y�i0z 54C�«RC �e��!P#/ !-��4(*+. %��C �6!'+�23 %�.+<-' %��'>��$ �}��(:+.��-L�(�;5�+�$Q�,)L�)20 {A;>;�4(* %# +�. 02@(&$4�6-'+.2e�* 02+!�$*+9(H>�CjE� !2M3'-'+ :2/�(�$* +)[�($4(/� 1�CEANC;«F +)L�($4(,#/ !-�(1�0'aE�$,��-��Q)[��$=(M�)(*+.�6- �(7�A N5 �o D����)� .�; 0-�(* %$%���J�(#R<�$4+�2��� (�x@1�(��:�&��2M3"!��4 !(*(,�%� w i 0!& Ct �(�0z 54C�«RC �e�B!�#$ 0-��=(:+. +�§C � %2' +$&�(�x5 U"+��)(*+.�6-I5}2�#$+.-3+��4(,$&�)(*+.�6-�2!��#S)P!3(: +$��* !2%!�$4+<(H>I)�����-P�%C�Eo 02M3'-3+.2/�0�$* %)���$=(/� 1�CEAjC�«F %)��($4(,#/ !-�(;�('lEF$&��-��Q)[�($4(M��(:+.��-��(7mA N5 �m D����)� }�; 0-�(: +$%��)�$4�x2P!'20 +2{<?>5A�20+< 0-'2! 7{ +�*��!�$420 +� 5 �,�*�"20+��)(: +�%�j�J�(#4<�$*+B2��6 (�L@1�(�,�,��2M3"!��* @(*(,�%� w i 0 0 Ct �xw%z 54C�«RC �e��!P#/ !-��4(*+. %��C �}��(:+.��-L�(�P5m+�$Q�,)L��2! {A;>;�4(* %# %�< 02@(&$*��-'+.2J�4 02+!�$*+9(H>�C�Eo 02M33-'+.2%�(��$* +)[�($4(/��1�CEAjC«F %)L�($=(&#$ 0-�(1�('DEF$&��-P�,)���$4(&�)(:+<�6-��(7mA N5 �m D���B)[ -�; !-�(* %$+�L�J�(#R<P$*+�2P�6 (�x@1�(�Q�&��2M3"!��4 !(4(&�%� w i 0 0 Ct ��umz 54C�«RC �e�B!�#$ 0-��=(:+. +�§C � %23 %$&�0�F5-U"+��)(*+.�6-�5}2�#$+.-'+B�4(,$&�)(*+.�6-A5 �=A1�* 02+!�$*+9(H>���202+$* %23+<(M��(:+.��-1��!'+B2' [:�.+.-3 %�%CPE� !2M3'-'+.2%�(��$4 %)���$4(%�!�}�)(*+.�6-��(�x�£-P�4(:+9(&!3(* H�6-$A"(&��-�2L�($Q2��*��-P2TEo 02M33-'���.�(�(>�� �W��+9(&3' +$,�,<P!�$,���@1�($Q>;����-�2D� w i6i�� Ct �(�0z 54C�«RC �e��!P#/ !-��4(*+. %��C � +2' %$,�(�65 U"+���(:+.��-©5}2�#$+.-3+��4(,$&�)(*+.�6-q5}�=A©�* !2%!�$4+<(H>���2!2%$* +2'+<(&�)(:+<�6- �()x:)��.+<2/�)(*+.�6-£2' +�*+���-DCgEo 02M3'-'+<2/�(��$* +)[�($4(/� 1IC°ANC�«F %)L�($=(&#$ 0-�( �('GEF$&��-P�,)���$4(&�)(:+<�6-��(7mA N5 �m D���B)[ �; 0-�(: +$%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+� w i6ixw Ct �0y(z 54C�«RC �e��!�#$ 0-P�4(:+< %��C � +2' %$,�(�.5 U"+��)(*+.�6-�5 2�#/+<-'+��=(&$,�)(:+<�6-~5}�=A��* !2%!�$4+<(H>|��2!2%$* +2'+<(&�)(:+<�6-|)�$*�0:��$&�(# +<-��4(,$,!'2@(:+<�6-��%ClEo 02M3'-3+.2/�0�N$4 %)���$4(%� 1�CEANCx«F %)��($4(,#/ !-�(;�('aEF$&��-P�,)���$4(&�)(:+<�6-��(7mA N5 �m D���B)[ �; 0-�(: +$%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+� w i6i�u Ct � �mz 54C�«RC��e��!�#$ 0-P�4(:+< %��C � %2' +$&�(��5-U�+��)(:+<�6- 5}2�#$+.-3+��4(,$&�)(*+.�6- �* 0-P�*+<(*+BU� ��()P)��.+<2/�)(*+.�6- �4 02+!x:$*+<(H> ��202+$* %23+<(M��(:+.��- ��!'+�23 %�.+<-' (C E� !2M3'-'+.2%�(�£$* +)[��$=(/� 1IC°ANC{«F %)L�0$4(&#$ 0-�(X�('ªEF$&��-��Q)[�($4(M�o:(:+.��-��(7mA N5 �m D����)� W�; !-�(* %$+���J�0#R<�$*+B2��6 0�@1�(�Q�&��2M3"!��4 !(*(,�%� w i6i?u Ct ���0z 54C�«RC �e�B!�#$ 0-��=(:+. +�§C �e$4+. @l,-��5�6- %�. !2!(,$*�6-'+<2I�4 02+!�$*+9(H> +<-�(&33 Y�;��#T#R!'-'+<2/�)(*+.�6-��+� �}�/U"+��?�)(*+.�6-��-�2 A;!�$QU� 0+��B����-320 ª�§� ��A�¡7 !-?U�+B$*�6-P#/ !-�(%CqEo 02M3'-3+.2/�0�-$4 %)���$4(%� 1IC°ANC�«F %)��($4(,#/ !-�($�('}E�$,��-���:)[��$=(M�)(*+.�6- �(7�A N5 �o D����)� 6�; !-�(* %$+���J�0#R<�$*+B2��6 0�@1�(�Q�&��2M3"!��4 !(*(,�%� w i6i(y Ct � &mz 54C�«RC �=��!�#$ 0-��=(:+< %�.��-�2LgPC��b(&�(C � �)(:+<�6-L�(�G5m+�$Q�,)L��2! A">x�=(: +# «6�)(&� �£-�(* %$*2M3���-��6 �m !(H�1��$Q\ %�. !2!(,$*�6-'+<2G�* !2%!�$4+<(H>�C�E� !2M3'-'+.2%�(�$* +)[��$=(/� 1IC°ANC"«F +)L�($4(,#/ !-�(1�0'�EF$&��-P�,)���$4(&�)(:+<�6-��(7mA N5 �m D���B)[ �; 0-�(: +$%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+� w i 0�0 Ct ��00z 54C�«RC �e�B!�#/ !-��4(*+. +�D��-�2 FC¢�GC@���-'-'+<-���C�5 2PU0��-'2! %2^5}!3(*��#S�)(:+<�6-GA;>;�4(* %#�U;!��<-' %$,�(<'+B�.+<(*+. +�D(*� %�. !2!(,$*�6-'+<24��(*(M�)2M\jC}E� !2M3'-'+.2%�(��$4 %)���$4(%� 1�CEAjCD«F %)��($4(,#/ !-�(m�('�EF$&��-P�,)���$4(&�)(:+<�6-��(7mA N5 �m D���B)[ �; 0-�(: +$%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+�8g(!��Z> w i 0 � Ct ��i0z 54C�«RC �e��!P#/ !-��4(*+. %�; !(T�(��C � %2' +$&�(�G5-U"+��)(*+.�6-�5 2�#/+<-'+��=(&$,�)(:+<�6-�$4 %)���$4(B(*���;��-���$* +�,�$�6-|��+�$(&$&� �/2�20�6-�(&$4���j2L�)(M�4��-�2�20�(#S#R!3-'+.2%�)(:+<�6-��*U;!��.-' +$&�(<3+��.+9(:+< %����-�2A�4 02%!P$*+<(H>(C�Eo 02M3'-3+.2/�0��$* +)[�($4(/�

1IC°ANCD«F +)L�($4(,#/ !-�( �('�EF$&��-��Q)[�($4(M��(:+.��-��(7mA N5 �m D����)� 4�; 0-�(: +$%�F�J�(#R<P$*+�2P�6 (�D@1�(�,�,��2M3"!��* @(*(,�%�w i6i�� C

¸:º �

Page 192: Practical Architectures for Survivable Systems and Networks (Phase

t ���0z 54C��;���Q�1 %�B�§C�Ax)� 02!+<l,2%�)(:+<�6-~��-P2ªU0�(�.+B2L�)(*+.�6-��('.���* 02+!�$*+9(H> )[���<+.2[>£#/�;2' %��C ������~ ­Q¦��P¤%¦"� �¥�®����P¤f��������� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� uxw � u ¡[² ��� � ��i � � +<�$,!��($Q> w i6i!� C�Ax)� 02!+��(�N�* 02@(:+<�6-��6- � ��$,#S�(�@� !(,3'�x2P�}�*!�$4��)[ Y� i�� Ct �Pw%z gPC FC �1�o�1 0- ��-�2�@ªC �XC m+<-'2M3' +>(C }®9& � �L¥H¨�&(­[®°¥ � ����¤[¥�¨@� � �L¨��[® �e�,¦(¥r®�����¦���� �R¨M¤[®9&��LCAx)�$*+<-��6 +$J D %$,���(��� �1 %$,�<+.-D� w i6i6i Ct �?umz �YCv54C �e$&�02��. [>�� �}C6@{!�\"3' %$°�4 0 (�R7�Cv54C �8���,�4�6-D�I��-�2 ��C�*!�\) !(&�%�PC «F !(* 02!(*+.-��q2'+��Q$,!�)3(*+BU� $*��!3(* %$Q�%²*5�2'+B�4(&$4+�<�!�(: %2�-3 !(H�1��$,\g#$�6-'+9(:��$4+.-��I�()�)P$*�?��2M3�C��£- �e­:� �M¨M¨*�(®%�"&m¤ ���6¥ ¨ +-+-/. ����� �

�,��¤[®°¬�� ��� �D¨��[¬x­ ®°¥ � ¦���� �=­ ® �m¦"���0� �W�0\;����-�2D���J�0�.+B'>�($*-'+��P� @1�/> w i6i 0 CG������� �;��#S)P!3(: +$A���2!+. @(H>�Ct ���0z gPC �=$* 0-�(&��-'����ANC�7�C�A�-��()�)D� �YC  RC"«F+��(�%�?E6C�9*C ���?�)-D�;9�CvE6C m +<[ +$,�. !+.-D�;�}C IC {��� �XC �IC"98 +U"+9(*(/���-�2 �}C�@�!�\"3' +$K�4 ! (C�5�-~�($*2M3'+9(: !2!(&!P$* S'>�($R�12'+B�4(,$*+�<P!3(: +2�+.-�(,$,!��4+.�6-ª2' !(* 02!(*+.�6-��Q>;�4(* %#{C��£-

���m¬;­ ¥�¨M¨@�L¥ �4¨ �P¦(­[¥u�O¨@�L¥{��� � ��¨[­�& � #1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥�� �J­:�m¬ �X#1���1�/¨[­&¨@���M¨[�)L�(�6 +� u � � y!�+.-^�* !2!(:+<�6- w�& ��;�6-320��$Q2D�j�J�(�.+Z'>��$*-3+��P�P@1�/> w i6ixw CL«F %)��($4(,#/ !-�(C�0'��ª-' +$,�(>(Ct �(y(z � C FC �=$*�"��\"�%C � ¨ � �m¥ ®��,¦(¯ � ¦�� � � ���L¥ � � ¤M¤%¦ �o¤?��� ����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(CA5}2�2'+B�*�6-;:d +�,�. [>��7C /�(23+.-����L@1�(�,�,��2M3"!��* @(*(,�%�8A" 020��-�2 +2'+<(*+.�6-D� w i6i!� Ct �!�mz �.C �e$Q>"-m�4�(�B'K�,�4�6-^��-�2{9*C¢@ªC {+<(*(%C �1 +>6��-�2�(&3' 6)�$4�x2P!'2!(*+BU"+<(H>T)L�($,�(2'�/�NC #1���B�X¬"�L®��,¦(¥�®����P¤����¥ ¨��I# � � y�w � 0 ¡[² w�w � w�u �x5 !���!��=( w i6i 0 Ct � �0z @ªC �=!�$,$4�o�.�+�;@ªC(5 <L�(2'+�����-P2X7�C �m ! %2�3��(#�Cx5q�<���6+.2D�('j�0!3(&3' !-�(:+.2%�)(:+<�6-DC3�I# � ­Q¦��P¤%¦"�[¥r®����P¤��� #1��� �j¬x¥H¨[­ ���o¤[¥H¨@�4¤[� 0 � w ¡[² w�0 � � � � � +<�$,!L�0$Q> w i�i�� Ct �!&mz 7�C d C �e!3(,�. %$+CX5 �,!�$VU6 +>x�('=)�$4�oU0�(<P�B> 2!��$,$4 02@(I'r�(!P�<(Q:�(:���< %$,��-�(F2%�<��2M\1�Q>"-'2M3�$4�6-'+��%�)(:+<�6-�(: !2M3x:-'+��"!' +�%CE� !2M3'-'+<2/�(�7C %)���$4(�E-@^: w��(�!� �(� � � 5 A;5 9F�)-����. [>R7C %�4 /�($42M3g�; !-�(: %$+� � +<�$,!L�0$Q> w i 0 0 Ct � 00z �J��-L�(2'+���-GA;>;�=(: %#T�{A� !2%!�$4+<(H>g�; 0-�(&$4 (�j�;��#T#R!'-'+<2/�)(*+.�6-P�;A" 02%!P$*+<(H>g�*�4(M�0<��.+B�,3�#$ 0-�(/� ����U� %$*-;:#/ !-�(k�('-�J��-��(2L�PCp#�¦��j¦��(®r¦�� ­ ¬?¤[¥�¨*� #1��� �j¬;¥�¨[­ �=­:�0�(¬v�[¥ � �m¦(¯±¬P¦(¥r®���� #�­ ®°¥H¨[­ ®r¦�� � ¨[­&¤[®����

� � �?¨[�vg���-"!L�($V> w i6i�� Ct �6i0z «RCEgPCF�J�($4-' +>(C �6!3��(M�)(*+.�6-P�8'K$*��# �e3���+�$Q#O��-£«6�/U"+�2�²65 98+9(*(&�< X7C %2 �;���(\ �('n(&$,!�(&3���(:�G 0-;:�.+��(3�(* 0-£��-P2���!'+�23 B�6- (&3' X�<�6-��A#S�($*2M3 (*���J�($Q2�(&3' T� �8E{A�$* +U�����!�(:+.��-DCWE� !2M3'-'+.2%�(�*$* +)[�($4(/��J�($*-' +�6+. :V@� +���<�6-,1m-3+BU6 +$,�4+<(H>?A��0'%(H�J�($4 ��D-P�6+.-' ! %$4+.-��X�£-��=(:+9(&!3(* (� ª+<(4(&�Q<�!�$,�(3D��� !-'-��Q>;�ZU(�)-'+��P�

w i6i 0 Ct &(�0z 7�C"�e3��($,)� 0-�(:+< %$���-�2S@ªC"Ax�(�.�6+B�%Cj@1�0�.+°� �8E{AN²02' !(* 02@(:+.-P��#S�(�<+.20+<��!���20�;2' H+.-S� �8E{AY�4�('%(H�e�($* 0C�£- �=­:� �M¨M¨*�(®%�"&m¤����1¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨x��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤£®%��R¨ �/¨@���M¨�� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤��=¬;­M¤[¬;®°¥m����# � �� �e$,!P�,�* +���+� �; %�B�6+�!P#��L5 )�$*+B� u0����� C

� 5*E �RCt &xw%z «RC @ªC0�e3' +�,�+C,A� !2%!�$4+<(H> +��Q�,!' +��+.-�#$��<'+��< ª20�;2' ��Q>;�4(* %#T�%CP�£- � �j­ ®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3�(3l¨��[¥r¬x­&¨4f�m¥H¨M¤�®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥K¤I¦���� �D¨��[¬;­ ®°¥��m�L)L�(�� %� w � w/y � w i6i 0 Ct &�umz «RC¢«RC0�e���0$,\ !(��(��C�#1��� �j¬;¥H¨[­M¤G¦(¥(�.®�¤��%� �N¦ �/¨F#1��� �j¬x¥r®%�"&6®%�S¥ ¨ �1� �m­±�T¦(¥�®����f�n&;¨[C � �)(:+<�6-L�(�7{ +�* /�0$*2M3S�;��!'-'2!+���� �}��(:+.��-L�(�"5�2%�(2' %#I> *$* +�,�%� u;w��Pw �;�6-P�4(:+9(&!3(*+.�6-I5 U� (CZ� d �(�Q3'+.-P��(:�6-��?«RC �}Cu(�(y�w�0 � � «F 020 +#R<� %$ w i6i�� C � +.-��(��$4 %)���$4({�('o(&3' fA;>;�=(: %# A" 02%!P$*+<(H>�A�(&!�2P>^�;��#S#$+<(4(: ! (C

¸:º �

Page 193: Practical Architectures for Survivable Systems and Networks (Phase

t &(�0z d CEgPC��e�.+<-�(*�6-DCGEG3' X�e�.+.-�(*�6-�5 2�#$+.-'+B�4(&$,�)(:+<�6-D�v� ����<+.2[>G�6-£�e$*+9(:+<2/�(�a�£-P'K$,�(�4(,$,!'2@(&!�$4 *$*��(* 02 :(:+.��-D² *$* %�4+�2' !-�(:+��0�.«F 020+B�*+<�6-�«F+�$4 02!(*+BU� ��� C�Eo 02M3'-'+<2/�(�.$4 %)���$4(%� 1�CEANC � ��U6 %$4-�#$ 0-�( d 3'+<(* ��()� %$+� u�u @1�/> w i6i 0 C

t &0y(z � C-�;��3' !-DC �;��#S)P!3(: +$^U"+B$,!��4 %�%C �£- �D¨��(¨@�L¥ �I� � ) 4 � � #1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ � �L®°¥�®r¦(¥r® �(¨#1���1�/¨[­M¨@���M¨[��)L�(�6 +� u0y�� � u���� C � �)(:+<�6-L�(� �e!P$* /�0!P�('mA"(&��-�2L�($Q2��%� �W��+9(&3' +$,�,<P!�$,����@1�($V>x����-�2D�u0y � u�� A� %)�(: %#4<[ +$ w i 0(y C87C %)�$4+.-�(: +2�+.-�7C 0+<-1EF!�$*-|�> %2DC¢¡[�Z�{� �m¦����M¨M¤4®%� #1��� �j¬;¥�¨[­ ���o¤[¥H¨@��D¨��[¬x­ ®°¥ �0�� D����C � ��5 $4(* 02M3 {��!��4 (�«F %2P3L�(#{�@1�(�Q�&��2M3"!��4 !(*(,�%� w i 0 0 C

t & �mz � CEgPC��;��$Q<L�)( ��PC��F-ª<�!'+��B2'+.-P���V>x�=(: +#S�k(,3L�)(��C+��B��'r��+�� � w i6i�� EG!�$*+<-���5 �e�($Q2�98 02!(,!�$* 0���C+<(,3�^'>���B�.���C+.-P�5+.-�(: +$QU"+. [� <?> �W�($* !- � $* !-�\� +�°¡ C�#1���B�X¬"�L®��,¦(¥�®����P¤/���Y¥ ¨k�I# � � �(y � i ¡[² &�u � i�� �A� %)3(* %#R<� %$ w i�iPw Ct &��0z � CEgPC��;��$Q<L�)( ���� gPC�AP�(�9(&�! %$%����-�2~�}C�E6C��e�.+<-��6 !-DC^@�!��9(:+<2%�}��(,3' $l�$,�4(4�* [U6 0-~>� /�($Q�%C^�£-��=­:� ��M¨M¨*�(®%�"&m¤B���W¥ ¨ � �j­ ®%�"&�!,�m®%�L¥F#1��� �j¬;¥�¨[­/#1���1�/¨[­&¨@���M¨[�PU6���B!�#$ y�� �N@��6-�(,U0�(�< (� �m [� g� %$Q�* +>(�

w i!&�u CP5 � � nA �$4 %�Q�%Ct & &mz �C°gPC��;��!�$4(*�6+��+� � C m [>x#S��-��+�J��-P2q«RC�9*C ��($4-L�(�+C©�;�6-32%!�$Q$* 0-�(/20�6-�(,$*���J�C+9(&3�$* %�(2' %$Q�O�)-�2�.$*+<(* %$Q�%C #1���B�X¬��L®��,¦(¥r®����P¤k���8¥ ¨��I# � � w/y � w�� ¡[² � �!& � � � 0 � �F2!(*��<[ +$ w i!&xw Ct &�00z �}C;�;�o�e��-S��-�2S�}C!*!DC�Ax!�$VU�+ZU0�(<'+��<+<(H>W'K$*�(# �8�*���W�v�1 %�($%²�EG3' G$* @(&$4��l'(��* !2%!�$4+<(H>X$4 %�"!'+B$* %#$ 0-�(%C�£- �C��¤[®°¥r®������J¦ �L¨[­&¤ � �m­G¥ ¨ +-+-/. �1� �m­@�T¦(¥r®���� �¬;­���® �m¦%®°¯±®°¥�� � �m­:��¤ � � � � � � -/.���)L�(�6 +�

y?� � y�& � �8$,���)-�2'��� � �.��$4+�2L�x� u�0 � ��� �F2!(:�(<[ +$ w i6i 0 CP�������GCt &�i0z «RC��e$&��+B�6 0-���-�2 �YCnA;!�#S#$ %$Q�,\�+��B�W�u +2��%C¢¡[C ���m­±�T¦(¯ � ¨[¥ �0�m¤ � �m­ ­ ¬"¤[¥u�;�m­ ¥ � #1��� �j¬;¥�¨[­

���o¤[¥H¨@�4¤ " � � � . -,& �H� � �m­:��¤ � �L����¥ ¨I�8¤M¤�¨M¤M¤@�O¨@�L¥F��� �o�m­±�T¦(¯ � ¨[¥ �0�m¤ � �m­ ­ ¬"¤[¥u�;�m­ �¥ �x#1��� �j¬;¥�¨[­ ����¤[¥�¨@�4¤[CkAx)�$4+.-��� %$V:§ D %$Q���(��� �; %$Q�.+<-D� w i6i(� C u0� : u & g(!��B> w i 06i � �m��U0��A"20��(*+��P��J��-L�(2L�xCt 0��0z � C��e$4+��=(:+��)-DC)1m-�2' +$,�=(M��-�23+.-��4'r�0!��<(V:b(:�(�. %$,��-�(�2'+��=(&$*+B<�!3(* %2g�V>x�=(: +#S�+CF#1���B�X¬"�L®��,¦(¥�®����P¤����8¥ ¨�I# � � �(y � u ¡ ² ��� � &�0 � � %<�$Q!L�($Q> w i6iPw Ct 0Pw%z @ªCx�e$*���Q<'+. ��-�2S�GC �C'Ax)��0���($,2DCN5�2!(*+BU� }2' ['> 0-��4 ��('D� 2!��#S)P!3(: +$=�V>x�=(: +# !P�*+.-P�R�(!3(*�6-'��#$��!���(�6 0-�(,�%C�Eo 02M3'-3+.2/�0�D$* +)[��$=(/�P«F %)L�($=(&#$ 0-�(H�('��;��#T)�!3(* %$CA"20+. !-'20 +�%�j�HAP« :]E.7G: i!� : ��� 0 � *!�$,2P!'

1m-'+ZU6 %$Q�*+9(H>�� d %�4(}9l�0'r�/>6 @(*(: 0�L�£-�2'+���-L�P� w i6i!� Ct 0?umz 7�C¢�}C;«6�(�. [>X��-�2�gPC �}C;«F 0-'-'+B�%Cj F+�$=(&!L�0��#/ +#/�($Q>��?)P$*�"20 %�Q�* +�%���)-�2S�Q3L�($4+.-�� +.-S@�!��9(:+<2%�%C;#1��� ��X¬��L®��,¦(¥r®����P¤I���W¥ ¨m�I# � � w(w � � ¡ �@1�/> w i�� 0 Ct 0��0z 7�C¢�}CD«6�(�< +>���-�2 �C �YC �m %!P#O��-3-DC85 �6 !-' %$,�(�Z:])�!�$Q)[���4 flL�< 4�V>x�=(: +# '>��$}�4 02!�6-�2L�($V>��=(:��$,�(�6 (C�£- � � � �S#1���1�/¨[­&¨@���M¨��=­:� �M¨M¨*�(®%�"&m¤�� �l¦(¯°¯�!,�m®%�L¥$#1��� �j¬x¥H¨[­�#1���1�/¨[­&¨@���M¨[�*)L�(�6 +� uxw�� � u�u�i CAx)L�($=(M��- �;�"��\"�%� �{�oU� %#R<� %$ w i � � Ct 0(y(z �YC d C�«6�0# ��-P2 IC°ANC*98+.-D�ª +2'+<(*��$,�+CX#�­ ���j¥£�*&(­Q¦ � � � ¤��{�m¯�¨ � �D¨��[¬;­[®%�"&£¥ ¨ �1� �m­±�T¦(¥r®����

��� �[®§¨[¥��mC/�}�)(*+.�6-��(�7{ +�* %�($*2M3{�;��!3-'20+B�§� �}�)(*+.�6-��(�L5�2%�(2' %#I> *$4 %�,�+� uxw��xw �;�6-P�4(:+9(&!3(*+.�6-S5 U� (CZ�d �(�Q3'+.-P��(:�6-��«RC �}C u(�0y�w�0 � w i6i � C � +<-L�(�D$4 %)���$4(C�('�(&3' I�e$V>x)�(:����$,�()�3'+<2 o���.+<2+>�A"(&!�2x>��;��#Y:#/+9(*(: ! (���=A � � � : ����i : �!�my�& � : � C¸:º±¹

Page 194: Practical Architectures for Survivable Systems and Networks (Phase

t 0!�mz gPC�5IC�«6�/U"+�2��4�6-DCl5}�V>x#T#$ !(&$4+.2m+��*�(���)(*+.�6-DC��£- �=­�� �M¨M¨*�(®%�"&m¤ ��� ¥ ¨ �e¨[¯ � ¥ ���,�L¬�¦(¯�#1��� �j¬;¥�¨[­�D¨��[¬x­ ®°¥ � � � �j¯±®��,¦(¥r®����P¤k#1���1�/¨[­M¨@���M¨[�")L�0�6 %� y�y � �0y �3Ax��-A«F+. +�6���x�J�(�<+B'>��$4-'+��P��«F 020 +#R<� %$ w i6i � C������� �;��#T)�!3(* %$mA��"20+< !(H>�C

t 0 �0z � CF«F ���)���.+���5IC¢9*C�«F���IAx��-�(:���+����-�2~7WCv54C �� +#S#$ %$4 %$+C d %<�<P$*���.�* +$,�X��-P2~�* !2%!�$4+<(H>�C��£-� �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤I®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��1&;¨@�L¥°¤R¦�����D¨��[¬x­ ®°¥ �0�L)L�0�6 %� u(�!� � u ��� � w i6i 0 C

t 0!&mz 7�C�«RC «F /��-DC ���m­±�T¦(¯ �}¤ �L¨��[¥K¤ ��� � ��%®°¯�¨ #1�0�;¨ �D¨��[¬x­ ®°¥ �0C *3L« (&3' :�*+��+� �;��#T)�!3(: +$ A"20+. !-'20 «F %)��($4(,#/ !-�(%� *$*+.-320 !(*�6- 1{-'+BU� %$Q�*+<(H>(� g���-"!L�($V> w i6i6i C3�(4(&)D² � �m�G�G�WCj2%�+C�)P$*+.-320 !(*�6-DCj %2�! �0�*+B)��0)�!�< �02�2' %��-x:H23+��,�4 %$=(M�)(*+.�6-DCv)�3�) � Ct 0 00z «RC¢�GCm«F 0-'-3+.-�����ANC �YCo5 \;���?@ªC� { 02M\"#O�)-D��E6C � C(9a!'-�(%�?@ªC(@���$Q�6 0-��=(: +$*-D�!FC �XC �m +!�#O�)-'-D���)-�27�C�7�CoA"2M3' %�B�§CY F+. [�.�6'>��$W#R!��<(*+��< +U6 +��2L�)(&�(<L�(�4 S�4 02+!�$*+9(H>�C ������ ­,¦��P¤%¦"�[¥r®����P¤���� ����� ¥u��¦(­&¨

� �"&(®%��¨M¨[­ ®%�"&(� w�� � u ¡[� � %<P$,!L�($V> w i 0 & Ct 06i0z «RC¢�GC�«F 0-3-'+.-�� ��-P2 FC �XC2�m +!�#O�)-'-DC|7{ +�"!'+�$4 %#$ 0-�(&�T��-�2|#$�x2' +�e'>��$Y��«6�nAN²*5 $* %�(�Z:�(:+�#$ +.-�(&$Q!��*+<�6-x:H23 !(: !2!(*+.�6-p [�x)� %$4(O�Q>;�4(* %#{C E� !2M3'-'+<2/�(�-$* +)[��$=(/�.�;�(#S)�!�(: %$�A�2!+. 0-320 �9l�(<���$,�)(:��$V>��AP7-�=�£-�(: %$4-L�)(*+.�6-L�0�§�L@? 0-��<� ��($,\�N�J�(�<+B'>��$4-'+��P�"5 !���!��=( w i�0!� Ct i��0z «F %)L�($=(&#$ 0-�(C�('�(&3' W5}$Q#4>jC1g��6+.-�(.Eo 02M3'-'+<2/�(�l5 $*2M3'+9(: 02@(&!�$4 (�LU6 +$,�4+.�6- � C � C*E� !2M3'-'+<2/�(�l$* +)[�($4(/�

� �$2! �0'�(&33 kA" 02%$4 !(&�($Q>��0'�(,3' W5}$,#I>���A� +)3(: +#R<[ +$ w i6i!& Ct iPw%z �XCN«F %�,#$ %2�(/� �XC � $&��-�\) %���N�)-�2£@ªC ��!'-���C-@{!��<(*+Z:H$4 02! 0+BU� %$ �0#R!��9(:+Z:]�* !-�2' %$C-' @(H�;�($,\{�* 02+!�$*+9(H>j²� �$2!+. 0-�(=�(!3(,3' 0-�(*+.2/��(: %2T#R!��9(:+<2/�(�=(��m'> ! %2�<L�)2M\jC�£- �=­�� �M¨M¨*�(®%�"&m¤m��� ������� 45� � # � � C(�������G�

w i6i?u Ct i?umz d CN«F+ �$ I�)-�2£@ªC��GC { %�B��#S��-DC �{ +��2'+B$* !2!(:+<�6-��C+.-?2%$V>;)3(:���($&�()�3?>(C ������ ­Q¦��P¤%¦"�[¥r®����P¤I���

�1� �m­±�T¦(¥�®���� � ¨��m­ �0� u�u � � ¡ � �m��U� %#R<� %$ w i!&�� Ct i��0z �.C d CG«F+ �Q\;�=(&$,�PC��;�0:b��)[ +$&�)(*+.-��ª�* +�;!3 0-�(:+��(�6)�$*�"20 +�,�4 %�%C �£-��=­:�*&(­,¦��B�X®%�"& 3�¦��"&(¬P¦ &;¨M¤�� �1�

� ¨@�L¬ ��¤�"Q¨*�(®°¥\�m­ &m�L)L�0�6 %� y?� � w�wou Cx5�2/�02' %#$+.2'*$* +�,�+� w i � 0 Ct i(y(z �.C d C"«F+ �Q\"�=(&$&�xCjEG33 �=(&$,!32!(&!P$* {�('[(,3' .E� }��#4!��<(*+�)�$4����$&�0#S#$+.-��-�Q>;�=(: %#{Ce#1���B�X¬"�L®��,¦(¥r®����P¤���W¥ ¨m�I# � � w�w � � ¡[�L@1�/> w i � 0 Ct i!�mz �.C d C�«F+ �Q\"�4(,$&�PC?� �W®�¤ �[® �j¯±®%��¨5��� �=­��*&(­Q¦��B�X®%�"&(C,*$4 0-�(:+<20 [: }�(�B�§���ª-����. [�;�"�;2��e�.+Z���+� �{ +�g� %$,�4 +>(� w i!&�� Ct i �0z gPC¢�GC�«F��<��*��-���-P2 �}CF7 �)-�2' %�B�§C �e!'+��B2'+.-P�A$* %�<+��(<P�. X�* !2%!�$4 520�(#S)�!�(:+.-P�{�V>;�4(: +#S�k��!3(f�('J!'-;:$* %�<+��(<P�. 8!'-P�* 02+!�$* 20�(#S)��6-' !-�(,�%C��£-��=­:� �M¨M¨*�(®%�"&m¤I���W¥ ¨ +-/. � ����� �,��¤[®°¬�� ��� �D¨��[¬;­ ®°¥��g¦����

�e­ ® �m¦"���m�L)L�(�6 +� w�0!& � w i�� � �6�(\"����-�2D��J�0�.+B'>�($*-'+��P�"5})�$4+�� w i�0 � C�������� �;��#T)�!3(: +${A��"20+. @(H>�Ct i!&mz ANC«F���. [UjC �D¨[¯ � � �¥]¦%®°¯±® ��¦(¥r®����LC�@��HE �$4 %�Q�%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+� u(���(� Ct i 00z �}C @ªC��*���<+��4�6- !(S�(��C A �6�k20 +$4(*+<l,2%�)(: �(&33 0��$V>�C|E� !2M3'-'+.2%�(�G$* +)[�($4(/�=�£-�(: %$4-' !(O�ª-��6+<-' 0 +$*+.-P�E��(�Q\ � ��$*2! (�vA� +)3(: +#R<� %$ w i6i6i C�3�(4(&)D² � �m�G�G�WCj+. @(,'�Cj��$,�!�0$Q'>2 �0$Q'>2 u��6i�� C (Q�"(%C

¸:º�3

Page 195: Practical Architectures for Survivable Systems and Networks (Phase

t i6i0z ��!P$*��)� /��-T�;�(#S#R!3-'+<(*+. %���;��#T#/+B�,�4+.�6-DC �1� �m­±�T¦(¥r®���� ¨�� ���m¯.�*& � �D¨��[¬;­[®°¥ � � �m¦(¯±¬�¦(¥r®���� #�­ ® �¥�¨[­ ®r¦ " � � � # & � �e­:� ��®�¤[®����j¦(¯ 6¦(­@�����L®�¤�¨*� #�­ ®°¥H¨[­[®r¦ "4��� �D­Q¦����M¨�� � ¨[­±�T¦���� �T¥ ¨ 4�¨[¥ ¨[­ �¯Z¦����m¤��I¦����£¥ ¨ �Z�L®°¥H¨*� � ®%�"&��"��� &m�ng(!'-' w i6iPw C� D +$,�*+<�6- w C u C�5-U0��+����(<��. Y'K$*�(# (,3' ���/2! '>��$ ���/2!+��(��*!�<P�.+.2%�)(:+<�6-�� �0'[(,3' -��!P$*��)� /��-g�;��#T#R!'-'+9(:+. +�%�?9�: u�i 0!� 9a!x�� %#4<[��!P$,����+<(* %# �J« :&xw : ixw : �(��u :��2�.:��}C"5}���4�Y�/U(�)+����0<��. .'K$*��# 1 ���J9l� � ��J�nA � 7{�"��# u � ��0��!� � � +�2�2P�. %$Q� �6$* 0 !-9F�)-' (���e3' %�9(: 0-P3L�(# 1 � ��9 ��A �W9 ��u � 5FgP����$ �fA;5 � �6�=Ax54�;5}# �m+B)�)� 0-�\"$* +!�� w i �x« �(���(��;�6-'- u � � %$Q#O��-?>(C

t±w����0z 7�C°ANC � �(<P$Q>�Cj�J�0)L�(<'+B�.+<(H>?:]<L�(�* +2X�(2�2P$* %�Q�*+<-���Cn#1���B�X¬��L®��,¦(¥r®����P¤{���G¥ ¨n�I# � � w�& � & ¡[² y?��� � yPwou �g(!��B> w i!&0y Ct±w��Pw%z @ªC � /��(&3' +$%CF7 �0)'+�2A�0)�)��.+<2/�)(*+.�6-7�('l�<+���3�(H�1 0+B��3�(e'>��$Q#O�(�L#$ !(,3'�;2��e'>��$n20�6-P�*+��=(: !-'2+>g��-L�(�Z>x�4 %�+C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��������� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� u0y � w�w ¡ ² i0y�i � i!�)i � �{��U6 %#4<[ +$ w i�i 0 Ct±w��?umz 7�C°gPC � !+. %$=(M�(�~��-�2FC �XC �{ %!�#S��-'-�C EG3' 1'>��!3-�2L�)(*+.�6-��/�('���)�$4��U(�0<��B>|�* !2%!�$4 ���)� %$&��(:+.-P��Q>;�4(* %# � nA ��A�¡ C��£-�=­:� �M¨M¨*�(®%�"&m¤I���6¥ ¨ 4W¦(¥r®����j¦(¯D#1��� �j¬x¥H¨[­$#1���1�/¨[­&¨@���M¨[�P)L�(�� %� �?u�i � ���(y C5 � � nA �$4 %�Q�%� w i!&�i Ct±w����0z �.C d C � %�<(* 0-D�«RC �e�(�B'r��-P�(�«RC«F /�)-D�j��-�2�«RCEANC d �(������2M3DC d %<1�Q)[�"��l,-P��²=5m-1�£-�(: +$*-' @(F2!�6-�?�(#$ (C��£- �=­�� �M¨M¨*�(®%�"&m¤����-¥ ¨54}®%��¨[¥H¨M¨@�L¥ 46¦(¥�®����j¦(¯�#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ �5#1���1�/¨[­&¨@���M¨[�?)L�(�6 +�

i!� � w��(� � �J�0�<(:+B#/�($* (�P@1�($V>;����-�2�� � � w�� �F2!(*��<� %$ w i6i!& C � �=AxE � �8�HA��}Ct±w��(y(z �}C � @(&�! %$I��-�2 � CF�e$*+B�4(*+���-DC �=!'+��B2'+.-��S'r�(!��<(V:b(*���. +$&��-�(63L�0$,2P�e�($* 72+�.�"2M\;�W'K$*�(# � �8E{Ax2!��#Y:)[�6-3 0-�(&�+C��£- �=­:� �M¨M¨*�(®%�"&m¤ ���}¥ ¨ +-+-+-?#1���1�/¨[­&¨@���M¨���� �4¨ �L¨@���?¦%¯�¨I#1��� �j¬;¥r®%�"& � �m­k#�­[®°¥r®��,¦(¯� � �j¯±®��,¦(¥r®����P¤[��)L�(�� %� ��i � & 0 �,AP�)- g����4 (�j�J�(�<+B'>��$4-'+��x�'g���-"!L�0$Q> w i�i 0 Ct±w��!�mz �.Cv54C � %!P�4(: +���)-�21E6CN@1�/>�l, %�B2DCGEG3' 4« �fAx5I²�1m-�#$ !({+<-P'>��$,#S�)(*+.�6-A�4 02%!P$*+<(H>?2M3L�0���. !-��6 +�.'>�($��)[ +$&�)(*+.-��X�V>;�4(: +# 2' %�4+��6-' +$,�+C ���L¨[­Q¦(¥r®%�"& ����¤[¥�¨@�4¤ �.¨���®§¨@�*� �?u � w ¡ ² � � u�u �,g��)-;!��($Q> w i6i 0 Ct±w�� �0z ANC � ��$Q$* %�=(/�{ %2'+9(:��$+C � �O¨[­�&;¨@�L¥5#1��� �j¬x¥§¦(¥�®����L� @��HE *$* +�,�%�6�J�(#R<�$4+�2��6 0� @1�(�,�,��2M3"!��* @(*(,�%�w i6iPw C �$4��2! 0 +2'+.-��(�{�0'�(,3' �m+.-�(,3{5m-'-"!L�(��� �}9oA{�;�6-P'> +$* 0-320 (Ct±w��!&mz ���< 02@(&$*��-'+.2 � $*�6-�(:+< %$ � ��!'-�2L��(:+.��-DCH#�­Q¦"���m®%�"&�� � � � �D¨��[­&¨[¥°¤f��� � ���[­ ���j¥r®���� �.¨M¤�¨,¦(­:� � �^®°­&¨ �¥]¦ � �C�m¯±®°¥�®��M¤��N# ® � �R¨M¤[®9&��LC �R��7{ !+����Z>X��-P2O5}�Q�*�"20+��)(: +�%�3A� %<L�0�4(:�()[�������J�0�.+B'>�($*-'+��P� w i�i 0 CZA� ! �(���4�7(,3' �7{+B�,\"� � ��$,!�#{�xU�����!P#/ w i �'-"!�#R<� %$ 0!& � w�& g(!P�B> w i�i 0 Ct±w�� 00z 54C � !����� !(*(&�P� �XC �C ª+.2!20������-�2 �YC; F+B�6-L�PC 1m-�2' +$,�=(M��-�23+.-��720�;2' 6#$��<'+B�.+<(H>(C ������ ­Q¦��P¤%¦"� �¥�®����P¤B��������� ¥u��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� u0y � � ¡[² �(y"u � � �Pw �P@1�/> w i6i�0 Ct±w��6i0z ANC �C � !����< %$���-�2Y«RC �YC�@� %�Q�* +$,�*2M3P#/+9(*(/�� +2'+<(*��$,�+C � ¦��m®%�"& ¥ �8¨[¥r¥�¨[­0� ��� �P¦����(®%�"& �1� �m­±�T¦(¥r®���� ¨�� ���m¯.�*& � �.¨M¤�¨,¦(­:� � � ¨M¨[¥ ��� �[®§¨[¥ � � ¤�4�¨M¨*�m¤[C �}�)(*+.�6-L�0�e7C %�4 /�($42M3©�;��!3-'20+B�§� � �)(:+<�6-L�(�5�2/�02' %#4> *$* +�,�%� u;w��Pw �;��-��4(*+<(&!�(:+.��-�5 U� (CZ� d �0�,3'+<-���(:��-D��«RC¢�}C u0�(y�w�0 ��@1�/> u(����� C � +<-L�(�$* %)���$=(C�('�(,3' �}�)(*+.�6-��(�a7C %�* %�($*2M3��;��!'-'2!+��F�;��#T#$+<(*(* 0 0Ct±w�w��0z @ªC ���(�Q�* +$%�654C � ���B2��4(* 0+.-��6�}C �W�(!P'K#S��-D�8�)-�2 �}C.9l�(#T)��4�6-DC EG3' ~«F+B�6+<(&�(� 23+��4(,$*+B<�!3(: +2�Q>;�4(* %#��4 02+!�$*+9(H>X�($42M3'+<(* 02!(,!�$* 0C��£- �=­:� �M¨M¨*�(®%�"&m¤m���e¥ ¨ �e¨[¯ � ¥ 4W¦(¥r®����j¦(¯8#1��� �j¬;¥�¨[­ �D¨��[¬;­ ®°¥��#1���1�/¨[­M¨@���M¨[�x)L�(�6 +� ���!� � �xw i � �e�(�<(*+�#$��$* 0��@1�0$Q>;����-P2D� w�� � w/� � 2@(:��<� %$ w i�06i C �-�=AxE ���}�HA��}C

¸:º@º

Page 196: Practical Architectures for Survivable Systems and Networks (Phase

t±w�w�w%z  RC�«RC �W�<+��6��$+�,ANCv�MC ���/U;$*+B���P����-�2�«RC � +$,$&�)+.���<��C �F-?(,3' �'>�($,#S�(�D2' @l,-'+<(*+.�6-?�('��* %)��($&�)(*+.�6-;:£�('�:2�!3(H>X)����.+<20+< %���)-�2B(&3' !+�$ª20�(#S)����*+9(:+<�6-DCP�£- �=­:� �M¨M¨*�(®%�"&m¤����.¥ ¨ +-+-/. ����� �,��¤[®°¬�� ��� �D¨��[¬;­ ®°¥��¦���� �=­[® �m¦"���m� �6�(\"����-P2D��J�(�<+B'>��$4-'+��P�x@1�/> w i�i 0 C�������� �;��#T)�!3(* %$mA��"20+. @(H>�Ct±w�woumz 54C � ����2P<[ +$,��C�5 �Q)[ !20+9l,2/�)(*+.�6-��0'ªg��/U0�X�.�?�(23+.-��X�)-�2^<">�(* 020�;2' WU6 +$*+<l'2/�)(*+.�6-DC��£-�*® � ¥ �I# �#1���1�/¨[­M¨@���M¨$���L#1��� �j¬;¥H¨[­T¦���� #1���B�X¬"�L®��,¦(¥�®����P¤ �D¨��[¬x­ ®°¥ �0�a)��(�6 %� y6i � ��0 �8AP��- � $&��-320+��420����J�(�.+Z'>��$*-'+��P� �m��U6 +#R<[ +$ w i6i 0 CP5-�G@ Ax� � Ax5-�}Ct±w�w��0z 9�C � �6-���CG5 �* !2%!�$4 I+�23 0-�(:+9(H>":]<L�(�4 %2 2%�()L�(<'+B�.+9(H>A�Q>;�4(* %#{C.�£- �=­�� �M¨M¨*�(®%�"&m¤B����¥ ¨ +-/. - ����� �

�,��¤[®°¬�� ��� �-¨M¤�¨,¦(­:� ®%� �D¨��[¬x­ ®°¥ ��¦���� �e­ ® �m¦"���m�a)L�(�6 +� ��� � ��� � �6�(\"����-�2��F�J�(�.+Z'>��$*-'+��P�a@���>w i 06i CP������� �;��#T)�!3(* %${A��"20+< !(H>(Ct±w�w/y(z 9�C � �6-��P�"@ªC;@�!' +���< %$%� �C�*$&�0'K!��B�.2M3L�)-�2�$&�x�"��-�2T7�C"A"2M3' %#$ %$Q�%C � �6+<-��6<[ [>6�6-P2/(&33 -�,��-�2�<��/�N²5�-���U� %$QU"+< +�X�('�(,3' {-' +� �4 02%!P$*+<(H>S�($42M3'+<(* 02@(&!�$4 m+<-$(,3' g��/U0�I«F [U6 +�.��)�#$ 0-�( � +<( w C u CD�£- �=­:� ��M¨M¨*�(®%�"&m¤k���8¥ ¨ � � � 4 �� ����� �,��¤[®°¬�� ��� �L¥H¨[­±��¨[¥ ¨�� ���m¯.�*&(®§¨M¤8¦���� ����¤[¥�¨@�4¤[��@��6-�(: +$* +>(��J�(�.+Z'>��$*-'+��P�x«F 020 +#R<� %$ w i6i!& Ct±w�w��mz 9�C ����-���� 7�C �m 0 +2�3L�(#{� ��-�2 7WC �=�(3L�(�<��#{C�7{ %�(�*��-'+.-����0<[��!�(g<� %�.+< +'�+<- 2%$Q>;)3(*����$,�()�3'+<2)�$*��(*��2!�����+C��£- �=­�� �M¨M¨*�(®%�"&m¤ ���-¥ ¨ +-+-�� ���)� �,��¤[®°¬"� ��� �-¨M¤�¨,¦(­:� ®%� �D¨��[¬;­[®°¥ �Y¦���� �=­ ® �m¦"���0�)L�(�6 +� u0�(y � u0y 0 � �6�(\"���)-�2D��J�(�<+B'>��$4-'+��x��@1�/> w i6i�� C�������� �;��#T)�!3(* %${A��"20+< !(H>�Ct±w�w��0z 9�C � �6-��4��-�2A7WC�A�2M3' %#$ %$Q�%Cl�H#T)��. +#/ !-�(*+.-���)�$4��(: !2!(:+<�6-O23��#O�)+.-��D+.-$(&3' Fg��/U(�I«F +U� %�.�()�#/ !-�(

��+9( w C u Ca�£- �e­:� �M¨M¨*�(®%�"&m¤���� ¥ ¨ �L¥H¨[­@��¨[¥ ��� �[®§¨[¥�� ����� �,��¤[®°¬"� ��� 4�¨[¥h�;�m­:�X¦���� �W®�¤[¥r­ ® %¬x¥H¨*����o¤[¥H¨@� �D¨��[¬x­ ®°¥ �0��Ax��-1«F+< %�6�P�L�J�(�<+B'>��$4-'+��P�x@1�0$*2M3 w i6i 0 C

t±w�w�&mz 9�C ����-��^��-�2£7WC8A�2M33 %#$ %$,�+CBA�+B�6-'+<-������4 /�(�<+.-��P�D��-�2��(!L�($,23+.-��Gg��/U0����<;�4 !2!(&�+CI�£- � �j­ ®%�"&;¨[­ �� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥°¤I¦���� �D¨��[¬;­[®°¥ �m�)L�(�6 +� u0� � � uxw � � w i�i 0 C

t±w�w�00z 7�C°ANC �6$&�/>��6«RC ���)(&�(� �YC.�=>;<� 0-�\)������-�2�«RCG7.!��%C «R�¢�0�6 0-�(&�+² A� 02+!�$*+9(H>X+.-��|#4!��<(*+�)��< [:����-��(!L�(�6 0��#/�(<'+��< [:��0�6 0-�(��Q>;�4(* %#{CN�£- � �j­ ®%�"&;¨[­ � � ¨[­[¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤-®%��#1��� �j¬;¥�¨[­���[®§¨@���M¨�� +-�� � ��%®°¯�¨m�1&;¨@�L¥°¤4¦���� �D¨��[¬;­[®°¥ �m�L)L�(�6 +� w��0y � w�0 & � w i�i 0 C

t±w�w i0z �C �6$* ! 0-DC�EG33 =�0$4(8�('�2%$4 /�)(*+.-��G$4 %�<+��(<��< ��4�('%(H�J�0$* [:]<L�(�4 %24�V>;�4(: +#S�l!��4+.-��C�(�:b(,3' [:]�,3' +�B';�*�0'%(H�J�($4 20��#T)[��-' 0-�(&�+CD�£- �=­:� �M¨M¨*�(®%�"&m¤ ���.¥ ¨ �® � ¥H¨M¨@�L¥ �L¥�¨[­±�j¦(¥r®����j¦(¯ ���)� �,��¤[®°¬"� ��� �.¨[¯±®r¦%¯�¨ �W®�¤ �¥�­ ® %¬;¥�¨*� ����¤[¥�¨@�4¤[�x)L�(�6 +� w�w�0 � wou(� �P«8!�$,3L�0#�� �m��$=(&3��J�($4���.+<-L�P� u�u : umy �F2!(:�(<[ +$ w i6i!& Cx��������;��#S)P!3(: +$�A"��2!+. !(H>(Ct±wou(�0z �MC �W$4 0 0-"<� %$Q���'�C �;�(!'2M3' %$+�W7�C-�e���($,\�6�GC�«RC{g� 0-��4 0-D�6E6C � C.9a!'-�(/�'FC �XC �m +!�#S��-'-D�6�)-�2«RC d +�����+CSEG33 S#R!P�<(:+B�. [U6 %���* 02+!�$* O$* /�0�Z:b(*+�#$ 42'+B�4(,$*+�<P!3(: +2 ��)� %$,�)(:+<-��^�Q>;�4(* %# �4(,!�2P>�COE� !2M3x:-'+.2%�(�R$* +)[�($4(/�T�;�(#S)�!�(: %$ A�2!+. !-'20 |9l�(<���$&�)(*��$Q>(�7AP7.�1�£-�(: +$*-L��(:+.��-L�(�§�X@� 0-��<� ��($Q\j�S�J�(�<+Z:'>��$*-'+��P� g(!3-' w i�i?u C��H�Q�,!' +2��(��7{�(#/ 9l�(<���$&�)(*��$Q>©$* %)���$=(17-9�:HE.7J: i�� : w��Pw �87C��#/ 9l�(<x:��$&�)(*��$Q> � � 5 � � �W$4+ �T�,�A5 � � ��� w��0y�y�w : � &(��� Ce�;�6-�(M�)2!({�*#/+B�.+< �A�+��($,\�+. [�C+.2+�(�-�£-�(* %$4-' !(%²A�+��($Q\�+. +�C+<2%�%���W�HANC�7-9�Cv5 � C @���9*�L)�33�6-' �Pw�� : ����� : �?u0y�w C � ��$ ���$20+��(� 1-�* � -P�B>�Ct±wouxw%z g(5 Ax5 A"(M�)-�2L�($Q2�� d ��$Q\"+<-�� �W$4��!�)DC g��6+<-�(���+B$,<���$*-3 xAx� �W� �-E �($42M3'+<(* 02!(,!�$* 0C�Eo 02M3'-3+.2/�0�$* %)���$=(/��EF5 A��}� w��xw � �)(:+<�6-L�(� �e!��4+.-' +�,� ��($Q\"�e�/>��5�-3-L�()����.+B�Cg(!'-'2@(:+.��-D�j@1« u(�!&(�Pw �vg(!'-' :g(!��B> w i6i 0 C�«8$,�0'%(/�* D %$Q�*+<�6- � �H20�6-�(M�)2!( ��(!P� 9*C d �(�,33+.-���(*�6-D�;g($%CZ� w : ���Pw : y!0�� : ������� �� [�"(%Cu(�Pw�& ������������ ����������������������� �jC

¸:º �

Page 197: Practical Architectures for Survivable Systems and Networks (Phase

t±wou�umz ANC }�0�. +U"+}��-�2 IC �W$,�/�;2+�+>;\C *!�<��<+.2[:]\� [>L2%$V>;)3(:���($&�()�3?> �)-�2 )L�(�Q�Q�1��$,2�)�$*�)(:�"20���B�%C��£-��® � ¥ �I# � #1���1�/¨[­M¨@���M¨?��� #1��� �j¬;¥�¨[­A¦���� #1���B�X¬"�L®��,¦(¥�®����P¤ �D¨��[¬x­ ®°¥ �0��)L�(�6 +� wou�u � w��Pw �AP��- � $,��-'2!+��*2!����J�(�<+B'>��$4-'+��x� �{��U6 %#4<[ +$ w i�i 0 C�5-�G@ Ax� �fA;5-�}C

t±wou(�0z 7�C d C �(#S#$+.-P��C1�*$Q$*��$R23 !(: !2!(*+.-��£��-P2 %$,$4��$k2!��$,$4 02@(:+.-P��20�;2' %�+C �8¨[¯°¯ ����¤[¥H¨@� ¨�� �L®��,¦(¯!v�m¬;­±�j¦(¯±� u�i ² w/y�& � ��� � w i!�(� C

t±wou0y(z gPC¢7WC { /�)(,3D� �C°gPC �6!' +\� %�+� ��-�2 7WCEANC d +��B�.+��0#S�+C 5 2' ['> 02@( (:���< %$&�)-�( �($V:2M3'+<(* 02!(,!�$* '>�($ 2M3' %#$+.2%�(���Z> �(�,�4 %#R<P�. %2 2!��#S)P!3(: +$,�%² EG3' �. +�,�4�6-�� �(' Eo %$&�o:#O��2 '>�($ (&3' �(�,)3+�$*+<-�� -L��-3��(: !2M3'-'���<���6+��=(/C Eo 02M33-'+.2%�(� $* +)[��$=(/� 18�J9a5I� w i6i!& C3�(4(&)D² � �)-3 0�6-DCj2M3' +#�Cv!'2%���PCj %2�!�� �/�*2M3"!'-��!�� ��$Q)���(* %$&�0#O��20C�3�(,#S��Ct±wou �mz E6C¢9� m +<[ +$,�. !+.-D� �}C(@�!�\"3' %$°�4 0 0�x�)-�2 �XC ��C(98 +U"+9(*(/Cx5q#$ !(,3'�x2f(:�82' @(: !2!(ª+<-�(,$,!��4+BU� G��2!(*+BU"+<(H> +<-�{-' @(H�;�($,\� +2B 0-?U"+�$4�6-�#$ 0-�(/C;�£- �=­:� �M¨M¨*�(®%�"&m¤C����¥ ¨����m¬;­ ¥�¨M¨@�L¥ 4W¦(¥r®����j¦(¯�#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥��#1���1�/¨[­M¨@���M¨[�x)L�(�6 +� � �?u � � &xw � d �(�Q3'+.-��)(:�6-D��«RC �}CZ� w � y �F2!(*��<[ +$ w i6iPw C � �=AxE � �8�HA��}Ct±wou��0z �}C { 0+9(&#$ +>6 +$%��gPC � +�$,<?>(�6g($+CB� �}Co9l�(<L�/�W�?@ C�5}$*2M33 %$%�(��-�2I7�C �=3L�($&�02P�J���+C 1-�*+<-��}�0<��4(,$&��2@(:+.��-��-�2~#$�x23 %�n2M3' 02M\�+.-P� (:��2' @(: !2!(X�,�0'> !(H> U"+.�����)(:+<�6-�� +.-�$* %�"!'+B$* +#/ !-�(,�R�,)� 02!+<l,2%�)(:+<�6-��+C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��� ����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� umy � w�w ¡[² i?u & � i0y!0 � �m��U6 +#R<[ +$ w i6i 0 Ct±wou &mz IC¢@ªC m+<-�(*�6-DC�#1��� �,��¤%¦%¯�¨ �N¦ �/¨[¥���¦���� �=­:�*&(­&¨M¤M¤ �=­:� �L¨[­[¥r®§¨M¤[C *3L« (&3' +�*+��+�)1m-'+ZU6 %$Q�*+9(H>��('E���$4�6-�(:��� w i6i!� Ct±wou�00z IC¢@ªC {+.-�(:��-DC 1{-�2' %$�:H�Q)[ !20+<l'2/�)(*+.�6-D�v2!��#S)����4+<(:+<�6-D�L�)-�2 +#/ +$,�6 !-�( )�$4��)[ +$4(*+. %�+CG�£- �=­:� �M¨M¨*� �®%�"&m¤f��� ¥ ¨ +-+- 4I¨@� �D¨��[¬x­ ®°¥ � �J¦(­,¦��(®9&��4¤ � �m­:��¤ � �j�x)L�0�6 %� 0�� � i�� �x9l��-P��2L�(�< (�P�e!�#R<�$4+��P�

1m-'+9(: %2�� +.-P��2'��#{�,A� +)3(: +#R<� %$ w i6i!& Cx5-�G@ Ax� � Ax5-�}Ct±wou�i0z IC¢@ªC m+<-�(:�6-DC��;��#T)[�(�*+.-P�R)L�($=(:+��0���B>?:]�,)� 020+9l, %2T�Q>;�=(: %#T�%C*�£- �=­:� �M¨M¨*�(®%�"&m¤ ���8¥ ¨�+-+-/. ����� �

�,��¤[®°¬�� ��� �D¨��[¬x­ ®°¥ � ¦���� �=­ ® �m¦"���0� �W�0\;����-�2D���J�0�.+B'>�($*-'+��P� @1�/> w i6i 0 CG������� �;��#S)P!3(: +$A���2!+. @(H>�Ct±w����0z � C m��3P�§CqEH+B#/ ^�<+�#$+<(: +2�<����)2M\;<��/�|�* !2%!�$4+<(H>j² *$*��(* 02@(:+.-P�ª#$��<'+B�. ^�(�6 !-�(&�Y'K$*��# #S�(�.+<20+<��!��3'���4(,�%C �£- � �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �}¨[­[¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤A®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨ � +-�� � ��%®°¯�¨�1&;¨@�L¥°¤4¦���� �D¨��[¬;­[®°¥ �m�L)L�(�6 +� i�u � w�w�� � w i6i 0 Ct±w��Pw%z �}C @ªC m���B�.���J�/>(� %2'+9(:��$+C � ®°­4� 4H� ��� 3a¦��"&(¯�¨�� ���m­±�T¦(¯ � ¨[¥ �0�m¤�� �m­:��¤ � �j� }�0#S)3(*�6-D� F+�$Q�6+.-3+��P��@1�/> w�� : w�u^w i�i!� C �-5 Ax5�9l��-����< +>^7C %�4 /�($42M3£�; 0-�(: +$%C �-5 Ax5��;�6-P'> +$* 0-320 *!�<��<+Z:2/�)(*+.�6- w��Pw�&�� �,g(!3-' w i6i!� Ct±w��?umz �YC°gPC� {�����+#O��-3-DC �R¨M¤[®9&���¦���� � ¦(¯±®u�?¦(¥r®����p���5#1��� �j¬x¥H¨[­ �=­:�m¥\� ���m¯¢¤[C *$* !-�(:+.2! [: }�(�B�§�D�ª-��(�. [:�;�"�x2��e�<+B�N�%� �{ +� g� +$,�* [>�� w i6ixw Ct±w����0z gPC� {��$*-'+<-��6��-P2 �}C07 ��-P2' %�B�§C �$4��2! %�Q���4(,$,!'2@(&!�$4+.-���C,�I# � #1��� �j¬x¥r®%�"& �¬;­��(¨��o¤[� � � w ¡ �?@1�0$*2M3w i!&(� Ct±w��(y(z gPCEgPC m��$4-'+.-P���� �C �}C(9l�(!' %$+� FC @ªC�@� %�B�.+��($V:\Ax#/+9(&3D�/��-�2 �}C07-��-�2' +���§C"5|)�$*�(��$&�(#��=(&$,!32!(&!P$* ='>�($ %$,$4��$423 !(: !2!(*+.�6-��)-�2~$* !20��U6 +$Q>(C��£- ���L¨[­,¦(¥r®%�"&����o¤[¥H¨@�4¤�� �=­:� �M¨M¨*�(®%�"&m¤����g¦�� �L¥�¨[­±�j¦(¥r®����j¦(¯

���)� �,��¤[®°¬"�k� 4 �m¥�¨M¤^®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨ � ��)L�(�6 +� w�&xw � w 0!& C�Ax)�$*+<-��6 +$V:] D +$,���(��� �; +$,�<+.-D�w i!&0y C¸:º �

Page 198: Practical Architectures for Survivable Systems and Networks (Phase

t±w��!�mz «RC�5IC !P�N#O�)-DCS5 #$ !(,3'�x2£'>��$F(,3' /2!�6-��=(&$,!32!(:+<�6-x�('J#$+.-'+B#R!�# $* +2�!'-�2L�)-'2+>x20�;2' +�%C �=­:� ��M¨M¨*�(®%�"&m¤I���6¥ ¨ � � � y?� � w i ��u Ct±w�� �0z «RC�5IC !P�N#O�)-DC©�J�)-'�6-'+<2/�(�J'>��$Q#S�X'>��$7+<-P'>��$,#S�)(*+.�6-x:]�.���Q�,�< %�,� l,-'+9(: [:]�4(&�)(: ^#S��2M3'+.-3 %�%C � � ­Q¦��P¤%¦"�[¥�®����P¤x��� #�®°­:�[¬;®°¥ � ¨��m­ � "�¤ �L¨��[®r¦(¯-¤[¬ � �j¯�¨@�O¨@�L¥ &�¦���� � � ­Q¦��P¤%¦"�[¥�®����P¤x��� � �� �m­@�T¦(¥r®���� � ¨��m­ ��"�¤ �L¨��[®r¦(¯�¤[¬ � �j¯�¨@�O¨@�L¥'&m���eEe: � ��-�2��HEe: � ² y�w � �)i ��@���> w i!�)i C�5 �,�<+���3�(&�Z>$* +U"+B�* %2�U� %$,�4+.�6-��0)�)[ %�($* +2 +.-��GC � C*@?����$4 (���*2DCZ� �D¨ � ¬¨@�L¥r®r¦(¯ � ¦"� ®%��¨M¤�� �D¨[¯�¨��[¥H¨*� �J¦ �L¨[­M¤[�5}2�2'+B�*�6-;: d %�,�< +>(�7{ %�(2'+.-P���@1�(�Q�&��2M3"!��4 !(4(&�%Ct±w��!&mz �������GC�A"(&��-�2L�0$,2~�Q)[ !20+<l'2/�)(*+.�6-���'>��$4)P!�<��.+<2S\) +>�2%$Q>;)3(*����$,�()�3?>�C�Eo 02M33-'+.2%�(�e$4 %)���$4(%���������A"(M��-P2L�($,2P�X«F %)L�0$4(&#$ 0-�(%� y�y�� {�� +�X9l��-' 0�2�C �XC �;�/� w/���Pw � ª+B�*2/��(M�/�J�/>(� ��g � 0 0!��� : w��(�Pw �u(����� ��-�2G�6-P�6�6+.-P��C�3�(*(,)D²����0��$*�(!�)[ +$%Cj+. ! 0 (Cj��$Q���0��$4��!�)�� � w�� ��� �xCt±w�� 00z 7�C�g��(�?�)-'-L�)(,3L��-A��-P2A�}Cx«F�x2�2�C ��9/1 )�$*���($&�(#T#/ +$%�v�=�(!'+�2' .U � C i CaE� !2M3'-'+<2/�(�N$* %)���$=(/�P�;��#Y:)�!3(: +$mA�20+< 0-'2! 49l�(<���$&��(:��$V>��vAP7.�e�£-�(* %$*-��)(:+<�6-L�(���L@� !-��.� ��($Q\�j�J�(�.+Z'>��$*-'+��P� �m��U6 +#R<[ +$ w i6i(y C�HAP9�Eo 02M3'-'+<2/�(�F7C %)���$4( �HAx9D: i(y : � � Ct±w��6i0z 7�Cvg��0�?��-'-L��(&3L��-���E6C � C9l!3-�(%�«RC�5�-P2' %$Q�*�6-D�N�}CL«F�;2�2D� � C � +���3��(#��P�}C�g��(���(�.+�� �CEAjC�g���U"+9(&�(�

�C �YC �m +!�#O�)-'-D�(5IC0E��(#S�($,!�����-�2I54Co ��(��23 %�%C'A;>;�4(* %#�«F %�*+B�6-R«F�"2%!P#/ !-�(%²)�m [�"(V:H�6 !-' %$,�)(:+<�6-�£-�(,$,!��4+.�6-;:�«F !(* 02@(:+.��-4���x)[ +$4(ªA;>;�4(: +# � � ��«6�nA�¡ C;Eo 02M33-'+.2%�(�x$4 %)���$4(%�?�;��#T)�!3(* %$�A�20+< 0-'2! J9l�(<x:��$&�)(*��$Q>(�vAP7.�e�£-�(: +$*-L��(:+.��-L�(�§��@� 0-P�.� ��($Q\j�j�J�0�.+B'>�($*-'+��P� i @1�0$*2M3 w i6i�� Ct±w/y?�0z �YC g��(\���<P�*�6-|��-�2|@ C¢«RC d !+��,�Q#O�)-DC�5}���($,# 20�($,$* +���)(*+.�6-�C ������ 4�¨[¥h�;�m­:�m��)L�(�� %� ��u � ��i �

�m��U6 +#R<[ +$ w i6i�� Ct±w/y�w%z ANC1g���-�(&�*2M3�C 7{+B�,\"�S<?>|!��4+.-���� �8E{A�)�$*�;2�!'2@(&�S��-�2 20��#T#/ +$*2!+��(�J�V�eE �4 %$VU�+<20 +�%C �£- �=­:� ��M¨M¨*�(®%�"&m¤����X¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨/��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬,�[¥K¤T®%���R¨ �/¨@���M¨� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤ �e¬;­&¤[¬x®°¥H���$# � �� �e$Q!��,�4 %�B�%� �; +���6+B!�#��x5})�$4+�� u0����� C � 5*E �RCt±w/y"umz IC°ANC�g���U"+9(&�-��-�2T54C? ��(�B2' %�+C�EG3' � ��«6�nAT�=(M�)(*+��=(:+.2%�(�'2!��#S)��6-' !-�(=23 %�*2+$*+B)3(:+<�6-O�)-�2W�Q!��=(:+9l,2/�m:(:+.��-DC*E� !2M3'-'+<2/�(�a$4 %)���$4(%�j�;��#S)P!3(: +$�A"20+. !-'20 �9l�(<���$&��(:��$V>��vAP7.�e�£-�(* %$*-��)(:+<�6-L�(���@� 0-P�.����($Q\��J�(�.+Z'>��$*-'+��P�P@1�($*2M3 w i6i0y Ct±w/y?�0z �.C�«RC�g� 0-��4 0-D�ngPCv54CFE� +�4(%��7�C�«RCF7{ [>�-3����2��+�*�GC �=!�$,\) (����-�2PgPC �XC }��-�\)��C{5}��)P3L��$4 %�. %�(�* u2' %�4+��6-R�Q!�#T#O�($V>W$* +)[��$=(/CxE� !2M3'-'+.2%�(�;$* %)���$=( 0 0Pw�u(� � �� !-�2L�(�B��Ax�"!L�($* J7{ +�* /�0$*2M3T�;��$Q)[��$,�)(:+<�6-D��J�(#R<�$4+�2��6 0�@1�(�Q�&��2M3"!��4 !(4(&�%��A� %)�(: %#4<[ +$ w i 0 0 Ct±w/y�y(z «RC¢7WC�g���3'-��4�6-D� � C � C�AP�/>;2m�,�($*+�����-P2 gPC FCF ��)-�E��(�,�4 %�§C1@��=A'A;���4 02+!�$*+9(H>�)����.+<2+>j²R5 '>��$,#S�(��()�)�$4�?��2M3DC�Eo 02M3'-'+<2/�(�a$4 %)���$4(%���FAx5 7 u A � :HE.7 ���Pw : i!� � w�0 5}!���!P�4( w i6i!� Ct±w/y��mz @ªC � C �W���0�,3'�" %\���-P2�5ICEANC�E���-' !-;<��(!�#{C � �(!��<(B(*���. +$&��-320 {!��*+<-��ª�($*��!�)p20�(#S#R!3-'+.2%�)(:+<�6-DC�I# � � � � � � ���L¨[­,¦(¥r®%�"& ����¤[¥�¨@� �.¨���®§¨@�*� u�� � u ¡ ² &;w � &0y �x5})�$4+�� w i6iPw Ct±w/y!�0z 7�C �W��+B���($I��-�2� 4C¢«RC �W�<+��6��$+C �F- (,3' � +U�����!�(:+.��- �('-<[ +�.+. ['K�I+.-��0!3(&3' !-�(:+.2%�)(:+<�6-�)�$4��(:�"20���B�%C�£- �=­:� �M¨M¨*�(®%�"&m¤B���W¥ ¨ ������ #1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ ���o�m¬����?¦(¥r®����P¤ � �m­:��¤ � � � � � $&�)-'20�6-3+��P�

�m +� }�(#T)��Q3'+�$4 (��g(!'-' w i�iPw Ct±w/y�&mz 7�C �XC �W��+.-���-�2|�}C��.C�9l��-�2P�1 %3�$+C �F-���202! %�Q�B2M3' 02M\�+.-P��+.-P2%�()L�(<'+B�.+9(H>":]<L�(�4 %2��V>;�4(: +#S�+C��£-

�e­:� �M¨M¨*�(®%�"&m¤I���8¥ ¨ +-/. � ������ ����� �,��¤[®°¬�� ��� �D¨��[¬x­ ®°¥ �g¦���� �=­ ® �m¦"���m�L5})�$4+�� w i�0 � C¸ ���

Page 199: Practical Architectures for Survivable Systems and Networks (Phase

t±w/y!00z @ªC �C �W��-��P��gPC �IC � $4���*2M33 %$%����-�2R�MC°ANC?@?���,\)�o�C+9(&�0C�5�-X�0$*2M3'+9(: 02@(&!�$4 e'>��$F#R!��9(:+��< +U� %�"�* !2%!�$4 e+.-x:(: %$4��)� %$&�0<'+��<+<(H>�C?�£- �=­�� �M¨M¨*�(®%�"&m¤C���=¥ ¨ � ®°­ ¥�¨M¨@�L¥ ���,�L¬�¦(¯�#1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ �{� � �j¯±®��,¦(¥r®����P¤#1���1�/¨[­M¨@���M¨[��)L�(�6 +� w i(y � u0�(y �DAP�)-�«F+. %�������J�(�<+B'>��$4-'+��P��«F 02! %#R<� %$ w i6i!& CF������� �;��#S)P!3(: +$A���2!+. @(H>�Ct±w/y�i0z @ªC �C �W��-������MCl@����Q\����C+<(,�(� �}Cl@?�6-�(&$*�(�* (�l�)-�2 gPC ��0$,�*��-' %�4 (CR5 2%�(�* Y�=(&!�2P> �('D(H�;� � 7 9)�!�#T)ª)�$4��(:�)(H>x)� %�+CO�£-��=­�� �M¨M¨*�(®%�"&m¤����Y¥ ¨ �e¨[¯ � ¥ ���,�L¬P¦(¯C#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ ��� � �j¯±®��,¦ �¥�®����P¤ #1���1�/¨[­&¨@���M¨[�0)L�(�6 +� �?u � y?� ��AP��-T«F+< %�6�����J�(�.+Z'>��$*-3+��P�m«F 02! %#R<� %$ w i6i � Cm�������~�;��#S)P!3(: +$A���2!+. @(H>�Ct±w��(�0z �Cv54C��W�($Q�6 %$+C9Z+B#/+9(:+<-��H(&3' G2L�0#O�(�� J)[�)(: 0-�(*+��(�"�('j2'+��42%$4 !(:+<�6-L�($V>4EF$*�o�,��-Y3'��$,�4 %�+Cj�£- �=­:� �M¨M¨*� �®%�"&m¤{����¥ ¨ +-/. ����� �,��¤[®°¬�� ��� �D¨��[¬;­[®°¥ �W¦���� �=­ ® �m¦"���0�0)L�(�6 +� �?u � �!& � �6�(\"����-P2D���J�0�.+B'>�($*-'+��P�5})�$4+�� w i�0!& C�������� �;��#T)�!3(: +${A��"20+. @(H>�Ct±w��xw%z �Cv54C �W�($,�6 +$%C � �j­:� ��®%�"& �D¨��[¬;­[®°¥ �Y¦���� �.¨[­ � �m­±�T¦����M¨ � �m­k#�¦ �P¦%®°¯±®°¥ � ����¤[¥H¨@�4¤[C *3L«a(,3' %�4+��+��;��#S)P!3(: +$69l�(<[�($&�)(*��$Q>(� 1m-3+BU6 +$,�4+<(H>��('e�J�(#R<�$4+�2��6 0�a�J�(#4<�$*+B2��6 (���ª-������)-�2D� �F2@(:��<� %$ w i 0 0 CE� !2M3'-'+.2%�(�F7{ +)[�($4( �m�PC w/y�i Ct±w���umz �YC �W�($°�4��(&3D��«RC �}Cl9l��-��6 0����-�2~@ªC��8�,3'+B#O�PCT5 �* 02+!�$*+9(H> #/�;2' %��'>�($I�0���. @(&�%CS�£- � �j­ ®%�"&;¨[­ �

� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥°¤I¦���� �D¨��[¬;­[®°¥ �m�)L�(�6 +� w 0 0 � u(� � � w i�i 0 Ct±w��(�0z gPC � +���* [>�� �}C�A�2M33-' 0+< %$%�N��-�2�«RC d �(�6-' +$%C *$4��(:�"20���8+<-�(: %$,��2!(*+.�6-P� �)-�2�(,3' �2M3'���* !-�)�$4��(:�"20����)(*(&��2M\"�%Cl�£-�� �j­ ®%�"&;¨[­ � � ¨[­[¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4 �m¥H¨M¤8®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� �D¨��[¬;­ ®°¥����=­:� �¥\� ���m¯¢¤�� �e­:� �M¨M¨*�(®%�"&m¤7��� � ¥ �L¥H¨[­±�j¦(¥�®����j¦(¯ � �m­���¤ � �j�N)L�(�6 +� iPw � w��(y � ��0$*+��+� � $&�)-'20 0�D5})�$4+��w i6i!& Ct±w��0y(z 7�Cv54C � %#T#$ %$* +$%C=5�-L�(�Z>;�0+.-P�$ !-'2%$V>;)3(:+<�6-1)�$4��(:�"20�(���G!��4+.-��Y'>��$,#S�(��U� %$4+<l,2%�)(:+<�6-?(* 02M3'-3+��"!' %�+C ������ !,�m¬;­±�j¦(¯���� �D¨[¯�¨��[¥�¨*�k�}­M¨,¦m¤�®%�P#1���B�X¬��L®��,¦(¥r®����P¤[� & � y ¡[² y�y!0 � y�� & ��@1�/> w i 0�i Ct±w�� �mz E6C � +.-P2�<[ +$,��CJ«F %<L�)(* (²JEG33+��-3'��!��4 4<� %�.+< +U� %�m(,3' �2' +U� %�.�()�#/ !-�(F�('*$4��<�!��=(}23+��4(,$*+B<�!3(: +21�V>x��:(: %#T�='K$4��# 20��#T)[��-' 0-�(&�n(:�R<� F+B#S)����,�4+�<��< (C ���L¨[­Q¦(¥r®%�"& ����¤[¥�¨@�4¤5�.¨���®§¨@�*� �(� � w ¡ ² w�� � w�& ��g���-;:!L�($Q> w i6i6i CTEG3' T2' %�42%$*+B)3(:+<�6-x�(';(,3'+��W2' +<L�)(: O�()�)� /�($4 %2 +.-��,7C %)���$4( �6-x(&3' T�ª+���3�(,3�5-�G@Ax� � � nA��*!�$*��)� /�)- d ��$Q\;�Q3'��)D�v��A">x�=(: +# Ax!�)�)���$=(6'>��$W�;��#T)[�(�*+.-P�A«F+��=(&$*+B<�!3(* %2�5})P)��.+<2/�m:(:+.��-��%�D¯.� �0�u�[®°¥�����)�)�C � � w�& Ct±w����0z ANC �6�.+B�6 %$+��ANC �n %#$+.-3+§� �RC �n %#$+.-'+���«RC �83��4+. (�m��-P2kAjC�A"(:���Z'>��Co5 20�;2'+.-P�.�()�)�$4�?��2M3�(:�C +U� 0-�(o20��$�:$* %���)(:+<�6-DCa�£- �=­:� �M¨M¨*�(®%�"&m¤f���}¥ ¨ ���m¬;­ ¥ �L¥H¨[­±�j¦(¥�®����j¦(¯ ����� �,��¤[®°¬�� ��� �L¥�¨�&(­Q¦(¥H¨*� 4�¨[¥h�;�m­:�

� ¦��j¦ &;¨@�O¨@�L¥ " � � ) ������ & � �N¦��L¥]¦ �-¦(­ M¦(­Q¦��{#Z��� � ¦ � +-+- � �L)L�(�� %� u�� � � u�& & CL�e3��()�#S��-� }�0���§�P98�6-�2'�6-���D-P������-P2D� w i6i � Ct±w�� &mz �}C ���PC � � ¨��[¬;¥�®���� � ���L®°¥£�m­[®%�"&$��� �D¨��[¬;­ ®°¥�� � #�­ ®°¥�®��,¦(¯ �=­:�*&(­Q¦��4¤-®%�^¦ �W®�¤[¥r­ ® %¬x¥H¨*� ���o¤[¥H¨@���;�

� �L¨��[® �e�,¦(¥�®���� � � ¦m¤�¨*�f� � �j­:�%¦"� C *3L« (&3' +�*+B�%���;��#S)P!3(: +$FA�2!+. !-'20 I«F %)L�0$4(&#$ 0-�(%� 1{-'+BU� %$Q�*+<(H>�('*�J�0�.+B'>�($*-'+��R�)(-«6�/U"+��%� w i6i � Ct±w���00z �C¢�}C � �"2M3' %$+CgEH+�#$+.-��{�)(4(M��2M\"�f�6-�+B#S)��< %#$ 0-�(M��(:+.��-��F�('.«F+ �$ [: { %�B��#S��-D�a7mAx54�F«�A'Aj���)-�2��(&3' +$R�Q>;�=(: %#T�%C �£- � �j­ ®%�"&;¨[­ � � ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥H¨M¤A®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨��{�{� ��m¦����M¨M¤�®%� #�­�� �j¥£�m¯.�*& �´���=­:� �M¨M¨*�(®%�"&m¤B���$#�­�� �j¥£� � - � �)L�0�6 %� w��(y � w�w�� �vAx��-�(M� �e�($,<L�0$&�P�j�J�(�<+Z:'>��$*-'+��P�P5 !���!��=( w i6i � C

¸ �´¸

Page 200: Practical Architectures for Survivable Systems and Networks (Phase

t±w���i0z ANCEAjC �6!��B\m�($*-'+;��-P2454Co5 $*��$,�PCx�;��#S)����4+<(:+<�6-L�(�02' %�4+��6-f�('L#R!P�<(:+9(:���< %$,��-�(a$* +)[ @(:+<(*+BU� ��>x�%��-�(:+<-' �(��$* ! %#$ 0-�(/C�=­:� �M¨M¨*�(®%�"&m¤����S¥ ¨ �D¨��(¨@�L¥�¨M¨@�L¥ �L¥H¨[­±�j¦(¥�®����j¦(¯C#1���1�/¨[­&¨@���M¨��������m¬"���?¦(¥r®����P¤��� ����� ¥h��¦(­&¨ ¨�� ���m¯.�*& � ¦���� � ¨��m­&¨[¥�®��,¦(¯F#1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� � ¦(­Q¦ & �j¬x­:� ���(®r¦(��)L�(�6 +�w��6i � w 0�� ��«F !20 +#R<[ +$ w i6i!& C

t±w����0z @ªC¢«RC�9l�(2P!' (C d 3' !- g��/U0���e�(�$�6-' 0²{EG3P$* /��(&�Y'K$*��# 3'���4(*+��< A<">�(* �2!�x2' 0C��£- �=­:� �M¨M¨*�(®%�"&m¤���I¥ ¨ 48®%��¨[¥H¨M¨@�L¥ 46¦(¥�®����j¦(¯n#1��� �j¬;¥�¨[­ �D¨��[¬;­[®°¥ ��#1���1�/¨[­&¨@���M¨[�)L�(�6 +� w/�(y � w�w�� � �J�(�<(*+�#$��$* 0�@1�($Q>;����-�2D� � � w�� �F2!(:�(<[ +$ w i6i!& C � �=AxE ���}�HA��}Ct±w��Pw%z 9�C�9l�(#S)���$=(/C6EG3' B+B#S)��< %#$ 0-�(M��(:+.��-��('�$4 %�.+��(<��< I2'+B�4(,$*+�<P!3(: +2�#R!��<(*+�)�$4��2! %�Q�}�Q>;�=(: %#T�%C #1��� �

�j¬x¥H¨[­ 4I¨[¥u�;�m­:��¤[� u ² i � � w�w/y � w i!& 0 Ct±w��?umz 9�C�9l�(#S)���$=(/C65 �4+�#T)��. 4�()�)�$4�?��2M3�(:�A�Q)[ !20+B'°>"+<-��520��-'2%!�$Q$* !-�(�)�$4����$,�(# �V>;�4(: +#S�+C #1���B�X¬ ��L®��,¦(¥�®����P¤I���W¥ ¨m�I# � � �?u � w ¡[² �?u � y!� �,g���-"!L�0$Q> w i�06i Ct±w����0z 9�C=9l�(#T)[��$=(/� d C �C �W�(!3(,�(� �C �XC �{ %!�#S��-'-D�.7WC�9�C1A�2M3?�e�($4(,�(� ��-�2FC @ CG@� +���.+��($V:\Ax#$+<(&3�C� �($,#S�(��(* 02M3'-3+��"!' %�G'>��$�'r�(!��9(;(:�(�. %$,��-'2! F+.-A2'+B�4(,$*+�<P!3(: +2A2L�)(M�I)�$*�"20 +�,�*+<-���C�Eo 02M33-'+.2%�(�D$* +)[�($4(/��;��#S)P!3(: +$FA�2!+. !-'20 I9l�(<[�($&�)(*��$Q>(��AP7-�e�£-�(* %$4-L�)(:+<�6-L�(���@� !-��.� ��($Q\�D�J�(�<+B'>��$4-'+��x�P5})P$*+�� w i 0Pw C� �($.7{��#$ 65�+B$G«F +U� %�<��)�#$ 0-�(}�; 0-�(: +$%Ct±w��(y(z 9�C-9l�(#T)[�($4(/�87�CmAx3'�(�4(M�0\j����-P2�@ªC � %�(�* 0C EG33 �=>;�/�)-�(*+.-' ª�6 0-3 %$&�0���{)�$*��<P�. %#{C �I# � � ��3�� �� y � � ¡[² � 0?u � y��Pw �3g(!��B> w i 0?u Ct±w��!�mz �}CF9F�0#S)��4�6-D��@ªCl5}<L�02'+§��@ªC �e!�$Q$*���.�%����-�2��.C d ��<�<� %$+Cg5}!3(,3' 0-�(*+.2/��(:+.��- +<- 23+��4(,$*+B<�!3(: +2�Q>;�4(* %#T�%²YEG3' 0�($Q>ª��-�2~)P$&��2@(:+.2! (C��I# � ���L¨[­Q¦(¥r®%�"& ���o¤[¥H¨@�4¤ �.¨���®§¨@�*� u � � � ¡ ² w�� � � w�0?u � �F2 :(:��<� %$ w i6iPw C%*$*�"20 ! %2'+<-����I�('H(,3' OEG33+�$4(* 0 !-�(,3�5-�G@ A;>;#S)����*+B!�# �6- �8)� %$&��(:+.-P��A;>;�4(* %#T�

�$4+.-'2!+�)��< %�+Ct±w�� �0z �}C d Cl9l�(#T)��4�6-DCT5 -3��(: 7�6-�(&3' 72!�6-3l,-' +#/ !-�(4)�$4��<��< %#{C�#1���B�X¬��L®��,¦(¥r®����P¤����Y¥ ¨k�I# � �

w�� � w/� ¡[² �Pw�� � �Pw�� � �F2!(:�(<[ +$ w i!&(� Ct±w��!&mz �}C d C�9l�(#T)��*�6-�C^7{ +2�!'-�2L�)-'2+>���-�2~$4��<�!��=(:-' +�,�I+<-�#$ %#$��$Q>�)�$*��(* 02@(:+.��-DC^�£- �1� �m­±�T¦(¥r®�����e­:� �M¨M¤M¤[®%�"& � " �=­�� �M¨M¨*�(®%�"&m¤����^¥ ¨ � � #1���"&(­&¨M¤M¤ +- �%&m��U6���B!�#/ � �($,2P�e�($4 {�Q�M�*)L�(�6 +�

wou�0 � w/�?u C �{��$4(,3x: {��������-�2D�;5}#T�4(* %$Q2L�(#{� w i!&0y Ct±w�� 00z �}C¢�GC�9l��-P2P�; +3�$%�x54C�7�C �e!��B�§�"gPC �CP@�2/«F +$,#$��(*(%�P�)-�2 d C°ANC��e33�6+§Ca5X(M�m���6-3��#4>$�('82!��#S)P!3(: +$)�$*���($&�(#��4 02%!P$*+<(H>���/�.�%���C+9(&3f [�P�(#T)��. +�%CPEo 02M33-'+.2%�(�x$4 %)���$4(%�"�; 0-�(* %$�'>��$�A� !2%!�$4 J�£-P'>��$Q#O�)(*+.�6-E� !2M3'-'���<���(>��*�£-x'>��$,#S�)(:+<�6- E� !2M3'-'���<���(>�«F+BU"+��4+.�6-D� �}�/U0�(�=7{ +�* %�($*2M3|9l�(<���$&�)(*��$Q>(� d �(�,33+.-��0:(:�6-D�«RC¢�}CZ� �m��U6 +#R<� %$ w i6i�� Ct±w��6i0z gPC :��}Ca9l�()�$*+< (C�«F %)� 0-P2L�(<��< I20��#T)�!3(*+.-��^�)-�2�'r�(!��9(�(:�(�. %$,��-'2! (²W�;�6-320 %)�(&����-�2 (* %$,#$+.-3���.���0>�C�£- �W®9&;¨M¤[¥ ��� �J¦ �L¨[­&¤��5� # � � ��)L�0�6 %� u � w�w ��5�-'-�5}$,<���$+��@�+<2M3'+�����-D�ªg(!3-' w i�0!� Cl��������;��#S)P!3(: +$�A"��2!+. !(H>(Ct±w�&(�0z �YC�98 �9l��-'-DC �$4 %2'+<2!(&�(<'+��<+<(H>{+.-�2+$*+<(*+.2%�(�(�V>x�=(: +#S�+C?�£- � �j­ ®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨�4f�m¥H¨M¤®%�S#1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� �o�m­±�T¦(¯ ¨�� �L® � ¬¨M¤O®%� �.¨,¦(¯ � ®%�O¨A¦�����a¦(¬x¯±¥ � �m¯�¨[­Q¦��L¥ ����¤[¥�¨@�4¤[�9a>"-��(<">(�j«F 0-�#S�($,\�vA" %)3(* %#R<� %$ w i6i�0 Ct±w�&xw%z �YC�98 �9F�)-'-DC *$4���('�:]<L�(�4 %2|�Q>;�4(* %# 0-���+.-' ! %$*+<-��ª��-�2p %#R<� %2�23 %2©�V>x�=(: +#S�+C©�£- � �j­ ®%�"&;¨[­ �

� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤I®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� � � [¨*���;¨*� ����¤[¥�¨@�4¤[� w i6i 0 C¸ ��

Page 201: Practical Architectures for Survivable Systems and Networks (Phase

t±w�&�umz d C�98 +�?�)(:�PC � ��$,#S�(��#$ !(,3'�;2��%²R�e3L��-��6+<-��{2'+�$4 02!(*+.�6-P�%CO�£- �=­�� �M¨M¨*�(®%�"&m¤����Y¥ ¨ � ®9& ¥�¨M¨@�L¥ 4W¦(¥r®����j¦(¯�#1��� �j¬;¥H¨[­ �D¨��[¬x­ ®°¥ � #1���1�/¨[­&¨@���M¨[� �J�(�9(:+B#/��$4 (��@1�($V>x����-�2D� w/� � w�� �F2@(:��<� %$ w i6i!� C� �=AxE ���}�HA��}C

t±w�&(�0z �IC �YC�9Z [U6 +�*�6-DC �N¦ �/¨@��¦(­&¨�� ���o¤[¥H¨@� �N¦ �/¨[¥ � ¦����p#1��� �j¬;¥H¨[­M¤[C£5 2�2'+��4�6-x: d +�,�. [>���7C /�(2'+<-����@1�(�,�,��2M3"!��* @(*(,�%� w i6i!� Ct±w�&0y(z �IC �YCa98 [U6 %�4�6-DC 1-�*+<-���� �6E{A 2!��#S)��6-' !-�(&��+.-��,�0'> !(H>?:b2%$*+9(:+<2/�(���Q>;�4(* %#T�%CX�£-��=­�� �M¨M¨*�(®%�"&m¤$���¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨{��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ ���=­:�0�(¬,�[¥K¤.®%� �R¨ �/¨@���M¨ª� � �j¯±®��,¦(¥r®����P¤��� ¨ �.¬;¥ ¯�¨M¤M¤ �=¬;­M¤[¬;®°¥H���$# � �� �e$,!P�,�* +���+� �; %�B�6+�!�#{�P5 )�$*+B� u(���(� C � 5*E �RCt±w�& �mz �IC �YCj98 +U� %�*��-£��-�2£@ªC �C��GC� { 0+�#T2L�(3P�§C �{ +���()�)P$*�?��2M33 %�m(*��2+$*+<(*+.2%�(�Z:]�Q>;�4(* %# �,!P$QU"+BU0�(<'+B�.+9(H>�C�£- �C��¤[®°¥r®������J¦ �L¨[­&¤ � �m­G¥ ¨ +-+-/. �1� �m­@�T¦(¥r®���� �¬;­���® �m¦%®°¯±®°¥�� � �m­:��¤ � � � � � � -/.���)L�(�6 +�

w�w�w � w(w/y � �8$Q����-�23��� � �<��$*+B2L�P� u�0 � ��� �F2@(:��<� %$ w i6i�0 CP�������GCt±w�&��0z �YC �IC098 +U"+<(4(/��AjC��e$4��2M\) %$%�"�)-�2X«RC(�e$&��+B�6 0-D�) %2'+9(:��$Q�%C; 6��7-\"�Q3'��)X�,�Q�M²0 D +$*+<l'2/�)(*+.�6-W�;�($,\"�,3'�()DC�I# � � � � � � ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"& 4f�m¥H¨M¤[� w�� � y ¡[² w � w���� �P5 !���!��=( w i 0!� Ct±w�& &mz �CL98+.-320���<-D�,gPC@?+<(:2M33 %�����L@ªCj@?+<(:2M33 %��������-P2{5ICvA�2! %2�$4�oUjC�5�)�$4��<L�(<'+B�.+B�4(:+<2 )����Z>":�(:+B#/ .'K$&�(#$ [:�;��$Q\ '>��$^)�$*��(*��2!������-L�(�Z>;�*+��+C �£- �*® � ¥ �I# � #1���1�/¨[­&¨@���M¨���� #1��� �j¬;¥�¨[­ ¦����S#1���B�X¬ ��L®��,¦(¥�®����P¤ �D¨��[¬x­ ®°¥ �0�=)L�(�6 +� w(wou � wou;w �1AP��- � $,��-'2!+��*2!���e�J�(�.+Z'>��$*-'+��P� �{�oU� %#R<� %$ w i6i�0 C�5-�G@Ax� �fA;5-�}Ct±w�&�00z �C�«RCG98+.-'2!���.-D� ��C.@1�($=(:+Z: �8�.+. @(/�G�)-�2 gPC.@� %�4 %��!3 %$%C Ax)[ !20+9l,2/�)(*+.�6-��{(,$&��-��V'>��$,#S�)(*+.�6-D�.�)-�2)�$*���($&�(#T#/+<-����(' 2!�6-'2+!�$,$4 0-�(g�V>x�=(: +#S�5+<-�$4 +�.$4+<(:+<-�� �.���6+<2(C�E� !2M3'-'+.2%�(� 7{ +)[��$=(�Ax7-�§:��HAP9�:

i(y : w(w ��;��#T)�!3(* %$�A�20+< 0-'2! 49l�(<���$&��(:��$V>���AP7.�J�£-�(: +$*-L�)(*+.�6-��(�§�@? 0-��<����0$,\�N�J�(�.+Z'>��$*-'+��P�L@���>w i6i(y Ct±w�&�i0z �C�«RC(98+.-320���<-4��-P27gPC @ C(7.!��,3"<?>�CP5�'>��$Q#O�(�B�B> U6 %$4+<l, +2X�(�B�6��$*+9(&3�#�'>��$�+<-�(: %$,��2!(*+BU� 12!�6-��*+B�4(* 0-'2[>!'-�2' +$6�O3?>;<�$*+B2�'r�(!��<( #$�x2' +�§C �£- �l¦(¬;¯±¥ �m¯�¨[­,¦��L¥F#1��� �j¬x¥r®%�"& ���)� �,��¤[®°¬"� � � �N)L�(�6 +� y?�?u �y�w�w � w i6i�� Ct±w�0��0z �C�«RCL98+.-'2!���.-A�)-�2�gPC @ªC7.!��Q3;<?>(C � ��$Q#O�0���B>XU� %$4+<l, +2��0���6��$4+<(,3�#S��'>��$J2'+��(�6-'�(�*+��;�('F#O��-3+B'> %�=(/��Q>;#S#$ !(,$*+<2(���<+.-�\����-�2 ��>x�%��-�(:+<-' g'r�(!��9(&�%C1E� !2M3'-'+.2%�(�.7C %)���$4(BAP7-�§:��HAP9�: i!� : w/y �*�;��#S)P!3(: +$A�20+< 0-'2! I9l�(<���$,�)(:��$V>��vAx7-�=�£-�(* %$4-L�)(:+<�6-L�(���L@� !-��.� ��0$,\�j�J�(�.+Z'>��$*-3+��P� �F2!(:�(<[ +$ w i6i!� Ct±w�0Pw%z �C�«RC.9Z+<-'20�(�.-D��gPC @ C.7-!��Q3"<">(�'�IC{Ax!P$*+§�}��-�2 �}C d �0�<(: +$%C .>x<P$*+�2 'r�(!P�<({�(�B�6��$*+9(&3�#T�%C��£-

�e­:� �M¨M¨*�(®%�"&m¤���� ¥ ¨ � ®°­*� 4H� ��� 3D¦��"&(¯�¨����o�m­±�T¦(¯ � ¨[¥ �0�m¤ � �m­���¤ � �,� � ¦ ���� � � ��+-+- � �)L�(�6 +� w i�� � u(��i C �-5 Ax5 9l��-����< +>g7{ +�* /�0$*2M3��; !-�(: %$+��g(!3-' w i6i!� Ct±w�0?umz 1ICF98+.-�2��?U"+��=(I��-�2 FC�5IC)���$Q$&�(�+CA«F !(* 02!(*+.-���20��#T)�!3(* %$���-�2 -' !(H�1��$Q\ #$+��Q!��* 7(&3P$*��!��(3 (&33

�$4�x2P!'2!(*+.�6-x: �J�(�4 %2^���x)[ +$4({A;>;�=(: %#�E��"�����4 !(6� �: �J�nAxE-¡ C��£- �=­:� �M¨M¨*�(®%�"&m¤f���}¥ ¨ +-+-+- ����� ��,��¤[®°¬�� ��� �D¨��[¬x­ ®°¥ � ¦���� �=­ ® �m¦"���0� �W�0\;����-�2D���J�0�.+B'>�($*-'+��P� @1�/> w i6i6i CG������� �;��#S)P!3(: +$A���2!+. @(H>�C

t±w�0��0z ANC � C"9Z+B)'-' +$%C[A� 02+!�$*+9(H>X��-P2S�4��!�$*2! C20�;2' .��202! %�Q�%²*�H�,�Q!' %�=��-�2Y$4 /�(�<+<(:+< %�+C��£- �=­:� �M¨M¨*�(®%�"&m¤����.¥ ¨� �+�+� ���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ ��¦���� �=­ ® �m¦"���0�F)L�(�6 +� woumy � wou � � �6�(\"����-�2D���J�(�<+B'>��$4-'+��P�F@���>u(����� CP������� �;��#T)�!3(* %${A��"20+< !(H>(C

¸ ���

Page 202: Practical Architectures for Survivable Systems and Networks (Phase

t±w�0(y(z �YC?98���1 (C �e$* %�(\�+.-�����-�2BlP��+<-�� (&3' �m ! %2�3��(#Y:\A�2M3�$4�� +2' %$�)�!�<P�.+.2 :H\) +>X)�$4��(:�"20�(�§²l5 20��#T)L�($4+Z:�*�6-5�0'�(H�1�X�()�)�$4�?��2M3' +�%Cl�£-�� �j­ ®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �}¨[­[¯±®%�3� 3l¨��[¥r¬x­&¨54f�m¥H¨M¤8®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� � � � � ��� �L¥�¨[­±�j¦(¥r®����j¦(¯5� �m­:��¤ � � ��� � �m¯¢¤4¦����B�}¯j&"�m­ ®°¥ �4¤ � �m­W¥ ¨�#1���P¤[¥r­ ¬v�[¥r®����ª¦�������j¦(¯ �o¤[®�¤I��� ����¤[¥H¨@�4¤[��)L�(�6 +� w/y�& � w � � � w i6i 0 C

t±w�0!�mz E6C�98���.#O��-R��-�2X«RC(@����4+. %$+C�5})P)��B>"+.-P�m(&33 G«F�?« � �?�(��A� !2%!�$4+<(H>I5}$*2M33+<(: !2!(,!�$* .�(���}#$ !(&33�x2x:���.���0>�'>��$$(,3' 123 +U6 +�.��)P#/ !-�(��('6�V>x�=(: +# ��-�2 0-�(: +$,)�$4+��* 1�* 02+!�$*+9(H>��($*2M3'+9(: !2!(&!P$* %�+C �£- �=­:� ��M¨M¨*�(®%�"&m¤/���X¥ ¨ � ®°­ ¥H¨M¨@�L¥ ���,�L¬�¦(¯;#1��� �j¬x¥H¨[­ �D¨��[¬;­[®°¥ �/� � �j¯±®��,¦(¥r®����P¤5#1���1�/¨[­M¨@���M¨[�N)L�(�6 +�w�0�� � w i�� �,Ax��-1«F+< %�6�P�L�J�(�<+B'>��$4-'+��P�;«F !20 %#4<[ +$ w i6i!& C�������� �;��#T)�!3(* %$mA��"20+. @(H>�C

t±w�0 �0z @ªCl9a!�<L�(�Q�0 +�.�Q\�+e��-P2 �}Ca�;��!�$4(*�6+��+CX5 $* +�.+��0<��. 4'r�)+��Z:]�&�0'> I�Q>;�4(* %#{C ������ ­Q¦��P¤%¦"�[¥�®����P¤$���#1��� �j¬x¥H¨[­&¤[���: y�& � u ¡ ² u(��� � u0y�w � � %<P$,!L�($V> w i6i�0 Ct±w�0!&mz E6C � C9a!'-�(%C=5 ����$* +�?�)(*+.�6-{��-�2?+.-x'> %$* !-'20 0² � ��2@(&�-��-�2^'r�(�B����2!+. %�+C��£- �=­:� �M¨M¨*�(®%�"&m¤I���6¥ ¨ +-/. - ������ ����� �,��¤[®°¬"� ��� �.¨M¤�¨,¦(­:� ®%� �D¨��[¬x­ ®°¥ �g¦������=­ ® �m¦"���m�@1�/> w i 0�i Ct±w�0 00z E6C � C�9a!'-�(/��7WC¢7WC A"2M3' %�B�§� d C�7�C Ax3'�"2M\"�. +>(�=@ªC { 02M\"#S��-D����-�2�«RC d �0$,$* !-DC�5 -3 /�($�:b(: +$,#2' %�4+��6-O'>�($1(&33 A� %�0 F+< +��#R!��9(:+��< +U� %�L2L�)(&�(<L�(�4 8�Q>;�=(: %#{CF�£- �e­:� �M¨M¨*�(®%�"&m¤���� ¥ ¨ +-/.+. ����� �,� �¤[®°¬�� ��� �D¨��[¬x­ ®°¥ �^¦������e­ ® �m¦"���m�N)��(�6 %� u(�(y � umy�y � �6�(\"����-P2D�D�J�0�.+B'>�($*-'+��P��5})P$*+�� w i�0 0 C��������;��#S)P!3(: +$�A"��2!+. !(H>(Ct±w�06i0z E6C � C�9l!3-�(%��54C�E��(#S�($,!D� � C � +���3��(#���7WCªg��(�?�)-'-L�)(,3L��-D�=�}CDg��(���(�.+�� FC �XC �{ %!�#S��-'-D� �CEAjCg���U"+9(&�(�;��-P2O54C� ��0��2' +�%C�5�7C /�(� :HEH+�#$ J�£-�(&$Q!��*+<�6-x:H«F !(: !2!(*+.�6-T���x)[ +$4(eA;>;�4(: +# �r��«6�nA�¡[C�E� !2M3x:-'+.2%�(��$* +)[�($4(/�x�;��#T)�!3(* %$1A�2!+. 0-320 -9l�(<[�($&�)(*��$Q>(�"AP7-���£-�(: %$4-L�)(*+.�6-L�0�§�;@� !-��.� ��0$,\���J�0�.+B'>�($*-'+��P�

u�0 � +<�$,!��($Q> w i6i?u Ct±w i��0z E6C � CJ9l!3-�(A��-�2�7�Cv54C d 3'+<(* %3"!�$Q�4(/C�EG3' xA� %�0 F+< +� '>��$,#S�(�C(:��) �< +U6 +�8�,)� 02!+<l,2%�)(:+<�6-��A�)-�2)�$*�"�('K�%C � +.-��(��$* %)���$=(/���;��#T)�!3(* %$IA�20+< 0-'2! A9l�(<[�($&�)(*��$Q>(�ªAP7.�6�£-�(: %$4-L�)(*+.�6-L�0�§�*@? 0-��<� ��($Q\��J�(�.+Z'>��$*-'+��P�vg���-"!L�0$Q> � � %<�$Q!L�($V> w i 06i CJ D���B!�#$ %� � 5��)-�2 � �a�('��:A" 02%!P$* X«F+B�4(&$4+�<�!�(: %2�«6�)(&� F+. [�.�%�v�5Ax7-� �$4�m�4 02@( w�w/y?� Ct±w iPw%z «RC�@1�0��\"3'+§��@ªC �YC�7C 0+<(* %$+�*��-�2~5IC¢«RC�7.!�<'+.-�C A� !2%!�$4 � [�� 02+!3(:+<�6- �('{g��/U0���()P)��. @(&�4!P�*+.-P���$* %#$��(* X)����/>;��$*�(!'-�2DCY�£-��=­�� �M¨M¨*�(®%�"&m¤����X¥ ¨ +-+-/. ���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥��1¦���� �=­ ® �m¦"���0�

�W�0\;����-�2D�L�J�(�.+Z'>��$*-'+��P�P@1�/> w i6i 0 C�������� �;�(#S)�!�(: %${A"��2!+. !(H>(Ct±w i?umz 54C �C�@1�)-' %\�+§C 5}�B�6 %<P$&��+<2S)�$4��)� %$4(*+. +�B�('-�Q>;�4(* %# 2!��#S)����4+<(:+<�6-�+<-�(&33 ^9Z�($&�(��� 1 �Z>x�Q�* +�S�)-�2@�2/98 /�)-5(&$&�)20 }#$�;2' %�B�%CD�£- �=­:� �M¨M¨*�(®%�"&m¤����}¥ ¨ .�¥ ������ #1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ � ���m¬"���?¦(¥r®����P¤

� �m­:��¤ � �j� � 0-P#O�($4 (��;�(!'-�(H>��� +$,$V>���H$* +����-�2��vg(!'-' w i6i � Ct±w i��0z @ªC;@1��-��4��!�$4+Z:=Ax�(#O�)-'+L��-�2O@ªC�Ax�<��#O�)-DCN@��6-'+9(:��$4+.-��62'+B�4(,$*+�<P!3(: +2S�V>x�=(: +#S�+C ������ 4�¨[¥u�;�m­��m�)L�(�6 +� u0� � ��� � �m��U6 +#R<[ +$ w i6i�� Ct±w i(y(z E6CL@1�($Q�,3£�> %2DC¢¡[C��e$*+9(:+<2/�(� � ��!'-�2��)(:+<�6-��%² �$4��(: !2!(*+.-��I5}#$ %$*+<2/�P�v�e�£-x'K$&�(�=(&$,!32!(&!P$* %�+C�Eo 02M3'-3+.2/�0�$* %)���$=(/� *$* +�*+B2' 0-�(/�v�6�;�(#S#$+��Q�*+.��-5�6-1�e$*+<(*+.2%�(���£-P'K$,�(�4(,$,!'2@(&!�$4 *$4��(: !2!(:+<�6-D� �F2@(:��<� %$ w i6i & Ct±w i!�mz «RCe@?2��e!��B�.��!��(3DCaAx)� 020+9l,2/��(:+.��-��T'>�($S#R!P�<(:+ :H�< +U6 +�G�* !2%!�$4+<(H>���-�2 � 3'�"��\�:H!�)�)�$*��)� %$=(H>�C��£-

�e­:� �M¨M¨*�(®%�"&m¤���� ¥ ¨ +-/. ���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥��Y¦���� �=­ ® �m¦"���0�;)L�(�6 +� w��xw � w�� � � �6�(\"����-�2D��J�(�.+Z'>��$*-'+��P�;5})�$4+�� w i�0!& CP������� �;��#T)�!3(* %$mA��"20+. @(H>�C¸ ���

Page 203: Practical Architectures for Survivable Systems and Networks (Phase

t±w i �0z «RC�@�2��e!��B�.��!P��3DC �{�6-'+<-�(* %$V'> %$* !-'20 1��-�2 20��#T)[�(�&�(<'+B�.+9(H>��('}�* !2%!�$4+<(H>|)�$*�()[ +$4(:+< %�+Cq�£- �=­:� ��M¨M¨*�(®%�"&m¤ ���^¥ ¨ +-/.+. ���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥���¦������=­ ® �m¦"���0�=)L�(�6 +� w�& & � w�0�� � �6�(\"����-�2D��J�(�.+Z'>��$*-'+��P�;5})�$4+�� w i�0 0 CP������� �;��#T)�!3(* %$mA��"20+. @(H>�Ct±w i!&mz «RCG@�2/�e!����<��!���3DC 1-�B>;�,�4 %�^�* !2%!�$4+<(H> )�$4��)� %$4(*+. +�g#/�;2' +�.+.-P�� 0-?U"+�$4�6-�#$ 0-�(/²�EG3' (&3' !��$Q> �('�* 02+!�$*+9(H>�CaEo 02M3'-3+.2/�0�N$4 %)���$4(%� �82P>;�,�4 +>O7{ +�* %�($*2M3g5 �,�4��2!+��)(* %�%�x�b(&3L�)2/�P� �m [� �n��$,\�3g(!��B> w i 0 0 Ct±w i 00z «RCe@?2��e!��B�.��!��(3DC©5 3'���(\;!P) (&3' !��$* +# '>��$S#4!��<(*+��. [U6 +�J�* !2%!�$4+<(H>�C ������ ­Q¦��P¤%¦"�[¥r®����P¤ ���

����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� w�� � � ¡[�'g(!'-' w i6i�� Ct±w i6i0z �YCN@�2 �W$,���WC d +B���8��)� 0-'+B�,3��*��!�$420 I$* /�0���B>5+�#T)�$*��U6 ��* !2%!�$4+<(H> ���£- �=­:� �M¨M¨*�(®%�"&m¤B����¥ ¨ � �+�+�

���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥���¦���� �e­ ® �m¦"���m�a)L�(�6 +� wou�0 � w�u�i � �6�(\"����-�2D�F�J�(�<+B'>��$4-'+��x�D@1�/> u0����� C������� �;��#T)�!3(* %$mA��"20+< !(H>�Ctvu(���0z �YCF@�2 �W$,�/� ��-�2ª�GC d C � %�9(: 0-�C !P¦ �m¦ �D¨��[¬;­[®°¥ �%� f��¤[¥r®°¯�¨k� � �j¯�¨[¥°¤�� f�m¯�¨M¤��8¦����5���L¥r®u�"�m¥�¨M¤[Cg���3'- d +��. [>A��-P2 A"�6-��%� �{ +� �n�($,\� w i6i!& Ctvu(�Pw%z �YC�@�2 �6$&�/����-�2£�GC d C � %�9(: !-DC �D¨��[¬;­ ®%�"& !P¦ �m¦+� � ¨[¥r¥�®%�"& �I���ª�£¥\� �.¬"¤[®%��¨M¤M¤f�*®°¥ � ��%®°¯�¨#1�0�;¨[Cng���3'- d +��< +>A�)-�2 A"�6-��%���{ +� �n�($,\� w i6i�i C*EG3'+��C+B�e(&3' W�* !20�6-P2 %23+<(:+<�6-��(' t�u0���mz Ctvu(�?umz gPCL@�2%9Z %��-DCF5 �6 !-' %$,�(�[(,3' 0��$V>��0'Z20��#T)[�(�*+<(*+.�6-Y'>��$D(&$,��20 8�4 !(,�H2%�.�(�* %2O!'-�2' +$G�* %�< 02@(:+BU� F+.-�(* %$V:�. /�/U"+.-P�Y'K!3-'2!(*+.�6-��+C=�£-�=­:� �M¨M¨*�(®%�"&m¤I���W¥ ¨ +-+-� ����� �,��¤[®°¬"� ��� �.¨M¤�¨,¦(­�� ®%� �D¨��[¬;­ ®°¥��g¦����

�e­ ® �m¦"���m�L)L�(�6 +� &�i � i�� � �6�(\"����-P2D��J�(�<+B'>��$4-'+��P�P@1�/> w i�i(y C�������� �;��#T)�!3(: +${A��"20+. @(H>�Ctvu(���0z �}CP@? /�(2'���.�+C����"(: !-�2'+<-��k(&33 <�$4 +�1 %$�:£-L�(�Q3g#$�x2' +�'(:�4��#R!P�<(:+B�. [U6 %�,2!�6-�(: ��(%Ca�£- �=­:� �M¨M¨*�(®%�"&m¤���I¥ ¨ +-+-�� ���)� �,��¤[®°¬"� ��� �.¨M¤�¨,¦(­:� ®%���D¨��[¬;­ ®°¥��g¦������e­ ® �m¦"���m�)L�(�6 +� i!� � w��?u � �6�(\"����-�2D��J�(�.+Z'>��$*-'+��P�P@1�/> w i6i�� C�������� �;�(#S)�!�(: %${A"��2!+. !(H>(Ctvu(�(y(z �}C;@� /�(23�o�.�+C�5 �Q>;�=(: %# '>�($ (&3' .�,)� 02!+<l,2%�)(:+<�6-Y��-�2S��-L�0�B>;�*+B�ª�('j\� +>Y#S��-L�0�6 %#$ 0-�(�)�$4��(:�"20���B�%C�£-�=­:� �M¨M¨*�(®%�"&m¤k���}¥ ¨ +-+-+ ���)� �,��¤[®°¬"� ��� �.¨M¤�¨,¦(­�� ®%���D¨��[¬;­[®°¥ �S¦���� �=­ ® �m¦"���0� �6�(\"����-�2D��J�(�.+Z'>��$*-'+��P�P@1�/> w i6iPw C�������� �;�(#S)�!�(: %${A"��2!+. !(H>(Ctvu(�!�mz �C¢@ªC�@� %�B�.+��($V:\Ax#/+9(&3 ��-�2�9�C��GC�@����4 %$%C Ax!P$QU"+BU"+.-P�a-3 !(H�1��$,\�)L�0$4(:+9(:+<�6-'+.-P��C #1��� �j¬;¥H¨[­[�

�Pw � � ¡[² �?u � � 0 �L@1�($42M3 w i6i 0 Ctvu(� �0z �C¢@ªCj@� %�B�.+��($V:\Ax#/+9(&3O��-�2{7�C�9*CvA�2M3?�e�($4(,�(C � �($,#S�(���Q)[ !20+<l'2/�)(*+.�6-{��-�2^U6 +$*+9l,2/�)(*+.�6-��0'ªAx� � E6²5 'r�0!��<(V:b(:�(�. %$,��-�(��,+B��3�(D20�6-�(&$4����Q>;�4(* %#{C ������N ­Q¦��P¤%¦"�[¥�®����P¤�����#1��� �j¬x¥H¨[­&¤[�P��: �Pw � & ¡[² �Pw�� �

����� �vg(!P�B> w i 0?u Ctvu(�!&mz gPCl@� %�4 %��!3 %$%C45 �.����+.2/�0�o(,3' 0��$V> �('n2!�6-'2%!P$,$* !-�(f�(<;�4 02@(&����-�2�+9(&�8$4 /�(�<+��/��(:+.��- +.- (,3' T@1�(!P2' ����-��(!L�(�6 0CI�£-��.¨M¤�¨,¦(­:� �W®°­&¨��[¥r®����P¤/��� #1�����[¬;­ ­&¨@�L¥ � � ¨��[¥ � �J­ ®§¨@�L¥H¨*� �=­:�*&(­Q¦��B�X®%�"&(Ca@��HE

�$4 %�Q�%�N�J�(#R<�$4+�2��� (�@1�0�,�&�)2M3;!P�* !(4(&�+� w i6i(� Ctvu(� 00z �YC�@� [>6 +$%�=@ªC���$Q�.+<-��6 %$+� gPC��; @(&�* +$%���}C�Ax!'-P�,3'+<-' (� �XC �����B2��,�+#/+B23(/�F��-P2 �XC��n %#$+.-3+§C^«F [:20 0-�(,$&�(�<+��0+<-���20�6-�(,$*���-��-�2 +.-�(: +���<+��6 !-'20 �+<- -' @(H�;�($,\�#O�)-L�(�6 +#/ !-�(%Cq�£- �e­:� �M¨M¨*�(®%�"&m¤ ���^¥ ¨

���m¬;­ ¥ � �L¥H¨[­±�j¦(¥�®����j¦(¯ ����� �,��¤[®°¬�� ��� �L¥H¨�&(­Q¦(¥�¨*� 4�¨[¥h�;�m­:� � ¦��j¦ &;¨@�O¨@�L¥ " � � ) ������ & ��N¦��L¥]¦ �-¦(­ M¦(­Q¦��/#�¦(¯±® � �m­±�L®r¦�� � ¦ ��+-+- � ��)L�0�6 %� y � w � C��e3L�()P#O��-p� }�(�B�§��98�6-�2'��-D�e�ª-��m:����-�2�� w i6i!� C

¸ �!¹

Page 204: Practical Architectures for Survivable Systems and Networks (Phase

tvu(�6i0z ANCF@�+.2%�(�.+�C � ��+B$8)�!�<��<+.2 :H\� [> 2+$Q>;)3(:�(�Q>;�4(* %#T�%CO�£- �{� �m¦����M¨M¤Y®%� #�­ � �j¥\�m¯.�*& �%� �=­:� �M¨M¨*�(®%�"&m¤����# � � � � � - � " � � �n� �.­ ®����?¨[¯°¯°�I¨*�(®°¥\�m­ &m��)L�0�6 %� �;wou � �xw�& C�Ax)�$*+<-��6 +$V:] D +$,���(��� �1 %$,�<+.-D��9F� �FA&0y?� � w i6i?u C

tvuxw��0z gPCP@?+����< 0-DC u(� >6 %�($,�1�('�2!�oU� %$=(e2M3L��-3-' %�j#/�;2' +�.+.-P�W��-�2g�)-L�(�B>;�4+��%CN�£- �=­:� �M¨M¨*�(®%�"&m¤ ���-¥ ¨ +-+-+-���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥���¦���� �e­ ® �m¦"���m�a)L�(�6 +� w�w�� � w(w/y � �6�(\"����-�2D�F�J�(�<+B'>��$4-'+��x�D@1�/> w i6i6i C������� �;��#T)�!3(* %$mA��"20+< !(H>�C*3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$*+�Cµ2!��# ���/#$+����< 0-��m)L�()� %$,� � u(� >;$4202(Cv)��+C

tvuxw�w%z gPCl@�+��B�. !-DC�� �$2!+. 0-�(W'r�(!��9(Q:�(:���< %$&�)-�(m20 +$4(*+<l,2%�)(: X$4 +U6�"2/��(:+.��-DC4�£- �D¨��(¨@�L¥ �I# � #1���1�/¨[­&¨@���M¨��� #1��� �j¬x¥H¨[­�¦���� #1���B�X¬"�L®��,¦(¥�®����P¤ �D¨��[¬;­ ®°¥��mCL5-�G@ Ax� �fA;5-�}� u0����� CDA;!�<�#$+<(*(* %2DCtvuxwoumz gPCJ@�+B���< 0-���-�2� �Ce7.!' %�Q�%C �$4��(:�"20�(�Z:£+<-�2' +)[ !-�2' 0-�(S�* !2%$* !2+>(C �£- �=­:� �M¨M¨*�(®%�"&m¤�����¥ ¨ � �+�+�

���)� �,��¤[®°¬"� ��� �D¨��[¬;­ ®°¥���¦���� �e­ ® �m¦"���m�a)L�(�6 +� w�w�� � w(w i � �6�(\"����-�2D�F�J�(�<+B'>��$4-'+��x�D@1�/> u0����� C������� �;��#T)�!3(* %$mA��"20+< !(H>�Ctvuxw��0z gPC �XCl@�+B���< 0-DC m�"��\"!�)£�* !2%!�$4+<(H>�'>�($8�Q>"-'2M3�$4�6-'��!P�I#S��2M3'+<-' %�+C4�£-��=­�� �M¨M¨*�(®%�"&m¤$���R¥ ¨ ������#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ ���o�m¬����?¦(¥r®����P¤�� �m­:��¤ � � � �*)��(�6 %� u � w/� � � $,��-'20��-'+��P� �m [� }�0#S)x:�,3'+B$* (��g(!3-' w i6i(y CP������� �;��#T)�!3(* %${A��"20+< !(H>(Ctvuxw/y(z gPC �XCN@�+��B�. !-DCe98�"2/�(�a$4 02!�6-3lL��!P$&�)(*+.�6-�)[���<+.2!+. %�+C=�£-��=­�� �M¨M¨*�(®%�"&m¤k���I¥ ¨ +-+-+- ���)� �,��¤[®°¬"� ���

�D¨��[¬x­ ®°¥ ��¦���� �=­ ® �m¦"���0��)L�(�6 +� y!0 � ��� � �6�(\"����-�2����J�(�<+B'>��$4-'+��x�F@1�/> w i6i6i Ca������� �;��#S)P!3(: +$A���2!+. @(H>�C*3�(*(,)D²����m�G�G�WCµ2+�,��C��Q$*+§Cj20�(#����%#/+B���. !-��0)L�0)[ +$,���m$* 02!�6-3lL�PC�)��+Ctvuxw��mz gPC �XCe@�+��B�. 0-�C A;!�$QU"+BU0�(<3+��.+9(H>~#$ /�(�Q!�$* 0C Eo 02M3'-3+.2/�0�}$* +)[�($4(/�{Ax7-�X�£-�(: +$*-L��(:+.��-L�(�}�;��#S)P!3(: +$A�20+< 0-'2! I9l�(<���$,�)(:��$V>��@? 0-��<� ��($,\�j�J�(�<+B'>��$4-'+��P�3g���-"!L�($V> w i6i�i Ctvuxw��0z gPC �XC @?+����< 0-DC Ax!�$VU�+ZU0�(<'+��<+<(H> #$ /�(�Q!�$* 0C Eo 02M3'-'+<2/�(� $* %)���$=(/� AP7-� �£-�(: +$*-L�o:(:+.��-L�(� �;��#S)P!3(: +$ A�20+< 0-'2! 9l�(<[�($&�)(*��$Q>(� @� 0-P�.� ��0$,\� �J�(�.+Z'>��$*-3+��P� g(!'-' u0����� C3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# ���/#$+��B�. 0- �0)L�()� %$Q���0#$ /�(�Q!�$* 0C�)P�%Ctvuxw�&mz gPC �XCj@�+B���. !-^��-�2{7WC d $4+���3�(/C��; +$4(*+<l,2%�)(: W$* [U6�"2/�)(*+.�6-�(,3' W$* %�Q)[��-��*+B<��. 6�e��>(C��£-��=­:� �M¨M¨*�(®%�"&m¤���.¦ �;�m­:��¤ � �?��� #1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ �´� �R¨ �L¨@���?¦%®°¯±®°¥ � �F¦������}¤M¤[¬;­,¦����M¨ "�# � �C� � -/.0&%� ��­:���

4I¨M¨*�m¤�¥£� ���m¯±¬x¥r®����P¤��;�m­:��¤ � �j� w i�i 0 C�3�(*(,)D² � �m�G�G�WCj2%�,��C��Q$*+�Cµ2!��#�� �/#/+B���< 0-��0)��()[ +$,� �)-' 0 +2��%Cv)��+Ctvuxw�00z gPC �XC?@?+����< 0-X�)-�2Y7�C d $4+���3�(/C�7{ %�(�*�6-3+.-��W�(<���!3(�(&$,!P�4(���-�2B+<-��,!P$&��-'2! H+.-Y�8)�!P<��.+<2[:H\) +>f+.-P'K$,�(�V:(&$,!32!(&!P$* (Ca�£- �=­:� �M¨M¨*�(®%�"&m¤ ��� ¥ ¨k#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ � �o�m¬����?¦(¥r®����P¤ � �m­:��¤ � �j�x�J�(#R<P$*+�2P�6 (��D-P������-P2D�vg(!��Z> u(����� C�3�(*(&)�²�� �o�G�G�WCµ2+�,�§Cv�,$4+§Cj20��# ���/#$+��B�. !-��0)L�()� %$Q���)+<-��,!P$&��-'2! (Cv)��%Ctvuxw i0z ANCN@�+��B�. %$+� �}C �m +!�#S��-D�[gPC[A�2M3'+��B�. +$%���-�2 gPC[AP�(�9(&�0 +$%C � +$,<� %$*�(�}�(!�(&3' !-�(*+.2%�)(:+<�6-1�)-�2��(!�(&3'�0:$*+��%�)(:+<�6-^�Q>;�4(* %#{C.E� !2M3'-'+.2%�(��$4 %)���$4(%�N@��HE *$*�m�4 !2!(85e(,3' 0-��OE� !2M3'-'+<2/�(� *����- A� 02@(:+.��-��GC u C w �uxw «F 020 +#R<� %$ w i 0!& Ctvu�u(�0z gPC �}C�@�+<(*2M3' %�B�§��@ªC�@�+9(:2M3' +���§�F��-P2 1IC�A"(* %$4-DCA5}!3(*��#S�)(: +2���-��(�B>;�*+B���('H2%$V>;)3(:���($&�()�33+.2T)�$*�0:(:�"20���B�I!��4+.-���#R!�$��=C^�£- �=­�� �M¨M¨*�(®%�"&m¤����S¥ ¨ +-+- ����� �,��¤[®°¬�� ��� �D¨��[¬;­ ®°¥��£¦���� �=­ ® �m¦"���0�)L�(�6 +� w%y�w � w��;w � �6�(\"���)-�2D��J�(�<+B'>��$4-'+��x��@1�/> w i6i!& C�������� �;��#T)�!3(* %${A��"20+< !(H>�Ctvu�uxw%z �.C � C=@��"��$* 0C � %2L�)-�\� !-L [�x)� %$*+B#/ !-�(&�$�6-q�4 %�"!' 0-�(*+��(�-#O�)2M3'+.-' +�%C��£- �}¬;¥\���T¦(¥§¦ �¥�¬3�(®§¨M¤�����,�j¦(¯¢¤ ��� � ¦(¥ ¨@�T¦(¥r®��,¦(¯ �¥�¬3�(®§¨M¤�� � �3� �=­ ®%���M¨[¥\��� �Z�L® �(¨[­M¤[®°¥ ���=­&¨M¤M¤���+- � � �")L�0�6 %� wou�i � w��(� �w i!��� C*�}C¢�GC[Ax3L��-3-'�6-���-�2 gPC@�2��J�0$4(&3?>(�[ +2'+<(*��$,�+C

¸ � 3

Page 205: Practical Architectures for Survivable Systems and Networks (Phase

tvu�u�umz �.C � C�@��"��$* 4��-�2£�}C��GC8Ax3L�)-'-'�6-DC}7{ +�.+��(<��. �2!+�$*2+!'+<(,� !P�*+.-P�g�. +�,�}$4 %�<+��(<��< W$* %���/>x�+C�!,�m¬;­@�j¦(¯ª���¥ ¨ ��­Q¦��3�m¯±®%� �P¤[¥r®°¥r¬x¥H¨[� u��?u ² w iPw � u(� 0 � u�0Pw � u�i!& �,A� %)3(* %#R<� %$+� �F2!(:�(<[ +$ w i!��� Ctvu�u(�0z 7�C�@���$Q$*+��}��-�2 �XCjEG3'��#T)��*��-DC ��(�,�V�;��$Q2£�* 02+!�$*+9(H>j²-5N2/�(�4 R3'+B�4(:�($Q>�C�#1���B�X¬��L®��,¦(¥r®����P¤B���¥ ¨��I# � � u�u � w�w ¡[² ��i(y � ��i!& � �m��U� %#R<� %$ w i!&)i Ctvu�u0y(z 7�CvE6C�@���$Q$*+B�%C��;��#T)�!3(* %$X�420+. !-'20 �(* 02M3'-'+<2/�(�G$4 %)���$4( w�w�& CªE� !2M3'-'+.2%�(�G$* +)[�($4(/��5*EC�6E �1 %���9F�0<[��$,�)(:�($*+. +�%��@�!�$,$,�/>� m+��B�§� �m [� g� %$Q�* [>�� u � � +<�$,!��($Q> w i 0!� Ctvu�u �mz 9�C�@����* +$%� �C¢@ªCm@� +���.+��($V:\Ax#$+<(&3��%��-P2I7WC A"2M3"�e�($=(&�(C"«F +�*+B�6-8U6 +$*+<l'2/�)(*+.�6-��('3Ax� � E6C?�;�6-�(&$&�)2!(:�($7{ +)[��$=( y?�6i!& � � 5FAx5 9F�)-����. [>A7C %�4 /�($42M3��; 0-�(* %$%� �(#S)�(:�6-D�x �5I��A� %)3(* %#R<� %$ w i 0 & Ctvu�u��0z @�!�2��6 / !(R�(�§CAEo %�=(:+�#$�6-?>x�('.9 � )�3�( m /�/U">ª�£-�2�!��=(&$*+< %�+C��£- �1¨,¦���#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ �1®%�

�m� �(¨[­@�,�O¨@�L¥ � ¤A¥ ¨ �=¬ %¯±®���¦(¥ �.®�¤�� � �¨,¦(­[®%�"&�� �D¨@�j¦(¥H¨ �¨,¦(­ ®%�"& �� � � � �%-�� �� 4 � � � �� � � � � � �m�*)L�(�6 +� &xw � iPw � d �(�Q3'+.-P��(:�6-���«RC �}CZ� w i @1�/> w i6i�0 C 1�CEAjC ����U6 +$*-�#$ 0-�(�*$*+<-�(:+.-P�� �$2! (C �8$&�(��(* %�=(:+�#$�6-?>�+B�H�6-^)L�(�6 +� u(u � y�w C

tvu�u &mz � 5 A;5 9l��-����< +>{7C %�4 /�($42M3£�; 0-�(: +$%C ���m­±�T¦(¯ � ¨[¥ �0�m¤ � �L¨��[® �e�,¦(¥r®���� ¦���� � ¨[­[® �e�,¦(¥r®����3� � �m¯ �¬��O¨ C2� 5 A;54��g(!'-' w i�i!� Ctvu�u�00z � 5 A;5 9l��-����< +>{7C %�4 /�($42M3£�; 0-�(: +$%C ���m­±�T¦(¯ � ¨[¥ �0�m¤ � �L¨��[® �e�,¦(¥r®���� ¦���� � ¨[­[® �e�,¦(¥r®����3� � �m¯ �¬��O¨ C �-5 Ax5I� � �0��� w i6i!� Ctvu�u�i0z � 5*E �RC �e­:� �M¨M¨*�(®%�"&m¤H����¥ ¨�4H� �X#1���1�/¨[­&¨@���M¨H����#1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬,�[¥K¤=®%��R¨ �/¨@���M¨{� � �j¯±®��,¦(¥�®����P¤�� � ¨ �.¬x¥ ¯�¨M¤M¤ �=¬;­M¤[¬;®°¥{���B# � �� �e$,!P�,�* +���+� �1 %����+�!�#{�x5 )�$*+B� u(���(� Ctvu(���0z �8�HA��}C ­[¬?¤[¥H¨*� 4�¨[¥h�;�m­:� �L¥H¨[­ �j­&¨[¥§¦(¥�®���� � � ��®°­:���,�O¨@�L¥K¤ �J¬;®u�;¨[¯±®%��¨[C �}�)(*+.�6-��(���;��#S)P!3(: +$A� 02+!�$*+9(H>{�; 0-�(: +$%� w 5}!���!P�4( w i6i�� C �8�HA���:]E �8: �Pw�w  D %$Q�*+.��-x: w Ctvu(�Pw%z �8�HA��}C ­ ¬?¤[¥�¨*� 4�¨[¥h�;�m­:� �L¥H¨[­ �j­&¨[¥]¦(¥r®���� " 4 &mC,�}��(:+.��-L�(���;��#T)�!3(* %$kA� 02+!�$*+9(H>~�; !-�(: %$+�

�Pw g(!��B> w i 0!& C �}�HA���:HE �}: �(�!�  D %$,�4+.�6-;: w �L7C %2 �;�"��\Ctvu(�?umz �8�HA��}C ­ ¬?¤[¥�¨*���I¦(¥§¦M¦m¤�¨ � ¦��j¦ &;¨@�O¨@�L¥ ����¤[¥�¨@� �L¥H¨[­ �j­&¨[¥]¦(¥r®���� ��� ¥ ¨ ­ ¬?¤[¥�¨*��#1��� �j¬;¥�¨[­

���o¤[¥H¨@� � �m¦(¯±¬P¦(¥r®���� #�­ ®°¥H¨[­ ®r¦�" � &mC,� �)(:+<�6-L�(���;�(#S)�!�(: %$IA� 02+!�$*+9(H>��; 0-�(: +$%��5 )�$*+B� w i6iPw C�8�HA���:]E �8: �?uxw �P D +$,�4+.�6-x: u �L9l�/U6 !-�2' %$ �;�"��\C

tvu(���0z �8�HA��}C��R¨ �P¦(­ ¥u�O¨@�L¥f�����4¨ �/¨@�P¤�¨ ­[¬?¤[¥H¨*�p#1��� �j¬;¥�¨[­ ���o¤[¥H¨@� � �m¦(¯±¬P¦(¥r®����S#�­ ®°¥�¨[­ ®r¦ " # �� � # &mC'� �)(:+<�6-L�(���;��#T)�!3(* %$�A" 02%!P$*+<(H>��; 0-�(: +$%�l«F !20 %#4<[ +$ w i 0!� C8« �W« : ��u(��� C u�0 :=AxE.«R� �8$V:��-��6 �;�"��\C

tvu(�(y(z �8�HA��}C �J¬;®u�?¦����M¨ � �m­I� � �j¯ �0®%�"&�¥ ¨ ­ ¬"¤[¥H¨*�P#1��� �j¬;¥�¨[­ ���o¤[¥H¨@� � �m¦(¯±¬�¦(¥r®����a#�­ ®°¥�¨[­ ®r¦1®%�� �L¨��[® �e� � � ��®°­:���,�O¨@�L¥K¤[C � �)(:+<�6-L�(�e�;��#T)�!3(: +$$A� 02+!�$*+9(H>|�; 0-�(* %$%�;g(!'-' w i 0!� C��HA���:=A;E.« :����� : 0!� � �n +���<�o� �;�"��\C

tvu(�!�mz �YC¢�}C �m !2%!����PC #1��� �j®°¯±®%�"&P�*®°¥ �=­�� ���&¤[C *3L«~(&3' +�*+B�%�}�;��#S)P!3(: +$?A�20+< 0-'2! £«F %)L�($=(&#$ 0-�(/��J�($*-' +�6+. :V@� +���<�6- 1m-'+ZU6 +$,�*+9(H>�� w i�i 0 Ctvu(� �0z �YC¢�}C��m !2%!����T�)-�2 FC98 0 (C=7C %�* %�($*2M3��6-^)�$*�"�('�:b2/�($Q$Q>"+.-��B2!�x23 W'>�($-!3-�(,$,!��=(: +2x:£2!�x2' ��* !2%!�$4+<(H>(C�£- �=­�� �M¨M¨*�(®%�"&m¤����T¥ ¨ +-+- ���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ �£¦���� �e­ ® �m¦"���m��)L�0�6 u0�(y � �6�(\"����-�2D��J�(�.+Z'>��$*-'+��P�P@1�/> w i6i!& C�������� �;�(#S)�!�(: %${A"��2!+. !(H>(C

¸ �0º

Page 206: Practical Architectures for Survivable Systems and Networks (Phase

tvu(�!&mz �YC¢�}C!�m !2%!����W��-�2 �C"98 ! (C[AP�0'> 0�?!'-�(&$,!P�4(: +2g�(�� 0-�(&�*!��4+.-��W)�$4���0'�:£2/�0$,$Q>"+<-��F20�;2' 0Cj�£- � �j­ ®%�"&;¨[­ �� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥°¤I¦���� �D¨��[¬;­[®°¥ �m�)L�(�6 +� �xw � iPw � w i6i 0 C

tvu(� 00z 7�C¢@ªC �m 0 +2�3L�(# ��-�2£@ C¢«RC�A�2M3�$4�� +2' %$+C 1 �4+.-��/ 0-'2+$Q>;)3(:+<�6-�'>��$ �(!3(,3' 0-�(:+<2/�)(*+.�6-1��-�2£�(!�(&3'�0:$*+��%�)(:+<�6-A�Q>;�=(: %#T�%Cf#1���B�X¬"�L®��,¦(¥�®����P¤f���6¥ ¨��I# � � uxw � wou ¡ ² i6i(� � i6i6i �P«F !20 %#4<[ +$ w i!&�0 Ctvu(�6i0z �}C �}C �m +!�#S��-R��-P24E6CoEG�%�j��C �� +$,<� %$4���%²F5�-4�(!3(&33 0-�(:+<2/�)(*+.�6-��* +$QU"+.2! ='>��$o20��#T)�!3(* %$o-' !(H�1��$Q\;�+C ������ #1���B�X¬"�L®��,¦(¥r®����P¤[� �?u � i ¡[² ��� � � 0 �3A� %)3(* %#R<� %$ w i6i0y Ctvu0y?�0z �C �YC �{ %!�#S��-'-�C�� �/2!+. !-�($ +$,$*�($V:H�<+�#$+<(*+.-��^U0�($*+��(<��. :H�< 0-���(,3�2!�x2' +�%C � �~ ­Q¦��P¤%¦"�[¥�®����P¤?���

�1� �m­±�T¦(¥�®���� � ¨��m­ �0�L�HEe: 0 ² u)i?u � ���0y �,g(!��Z> w i��?u Ctvu0y�w%z �C �YC �m +!�#S��-'-DC �F-g� 2%���(�,�1�('� �/2!+. !-�(; %$Q$*��$�:H�.+B#/+9(:+<-��}U0�($*+��(<��< [:H�< 0-��)(&3B20�;2' +�%C � �N ­Q¦��P¤ �¦"�[¥�®����P¤I��� �1� �m­±�T¦(¥�®���� � ¨��m­��m���HEe: 0 ²EA u���� � u � � �vA� +)3(: +#R<� %$ w i �?u Ctvu0y"umz �C �YC �m %!P#O��-3-DC4�*$Q$*��$�:H�.+B#/+9(:+<-��B20�;2'+.-P�A!��*+<-��5+.-x'>��$,#S�)(:+<�6-x:]�.���Q�,�. +�,�.�* +�"!' 0-�(:+��(�*#S��2M3'+.-3 %�%C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��� �1� �m­±�T¦(¥r®���� � ¨��m­ �0���HEe: w�� ² w�� 0 � w�w�� �x5})�$4+�� w i��(y Ctvu0y?�0z �C �YC��m %!P#O��-3-DC�EG3' J$4���. 1�('#$��(&3' +$,3'�"�;2I+.-k(,3' J)���)X�($=( �('�V>;�4(: +# )�$4����$&�0#S#$+.-��PC;�£- �=­:� ��M¨M¨*�(®%�"&m¤����X¥ ¨f�I# � �D¨�������� ����� �,��¤[®°¬�� ��� ���L¨[­Q¦(¥�®%�"& ���o¤[¥H¨@�4¤ �=­ ®%���[® �j¯�¨M¤�� �=­[®%���M¨[¥£���

4I¨@� !L¨[­&¤�¨��0�L)��(�6 %� w�� � w�0 Cx5-�G@ª� � 2@(:��<� %$ w i��6i Ctvu0y�y(z �C �YC �m %!P#O��-3-DC A;>;�4(* %# 2' +�*+B�6-�'>��$�2!��#T)�!3(: +$F-' @(H�;��$Q\"�%C4�£-X#1��� �j¬;¥H¨[­ � #1���B�X¬"�L®��,¦(¥r®����4I¨[¥u�;�m­:��¤ "�# ¦ �j¥H¨[­ � &m�j)L�(�6 +� u�i � 0Pw C *$* 0-�(*+.20 : �(����� w i!&xw C �ICj5}<�$,�(#T�*�6-��)-�2 � C � C �6!'��u %2P�%C¢¡[Ctvu0y��mz �C �YC �m %!P#O��-3-DC��;��#T)�!3(* %$g�4 02%!P$*+<(H> +U0�(�B!L�)(:+<�6-DC��£-a� � � ��#1���1�/¨[­&¨@���M¨ �=­:� �M¨M¨*�(®%�"&m¤��

4B#H#���)L�(�6 +� w�� 0!& � w��6i!� Ca5 � � nA *$* +�,�%�;g���-"!L�($V> w i!&�0 C17{ +)�$*+<-�(* %2 +<-�7{ !+.-~EF!�$4-��u %2�C ¡ ��m� �m¦����M¨M¤W®%� #1��� �j¬;¥H¨[­ �D¨��[¬x­ ®°¥ �0�L5 $4(: !2M3 {��!��* 0�j«F %2�3L�0#���@1�(�,�,��2M3"!��* @(*(,�%� w i�0Pw Ctvu0y!�0z �C �YC �{ %!�#S��-'-�C �F- 33+. %$,�($*2M33+.2/�0��2' %�4+��6-��('120�(#S)�!�(: %$6�V>;�4(: +#S�W'>��$F2+$*+9(:+.2%�(���0)�)��.+<2/�)(*+.�6-P�%C ������ ­Q¦��P¤%¦"�[¥�®����P¤?��� ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­[®%�"&(�nAx��: wou � i ¡[�;A� %)�(: %#4<[ +$ w i 0 � C�7C %)�$4+.-�(: +2+.- 7C 0+<-©E�!P$*-��u +2DC ¡ �m�m� �m¦����M¨M¤1®%� #1��� �j¬x¥H¨[­ ����¤[¥�¨@� �D¨��[¬;­[®°¥ �m�. D�(�§C � �.5}$4(* 02M3 m�(!��* 0�«F %2�3L�0#��@��(�,�,��2M3"!��* @(*(&�+� w i�0 0 Ctvu0y�&mz �C �YC �m +!�#O�)-'-DC �F-�(,3' g2' +�*+B�6-P�('.2' +)[ !-�2L�(<P�. 52!��#S)P!3(: +$4�Q>;�=(: %#T�R'>��$ 2%$4+<(:+<2/�(���()P)��.+<2/�m:(:+.��-��%CNE� !2M3'-'+.2%�(�j$* %)���$=(/�x�;��#T)�!3(: +$1A�20+< 0-'2! 89l�(<���$&�)(*��$Q>(�"AP7.���£-�(: %$4-L�)(*+.�6-L�0�§�;@� !-��.� ��($Q\��J�(�.+Z'>��$*-'+��P� � 2@(:��<� %$ w i6i�� C��HAP9ªE� !2M3'-'+.2%�(�l7C %)���$4(}�HAP9�: i(� : w�� Ctvu0y!00z �C �YC2�{ %!�#S��-'-DC|7-��+.-"<����.�S�)-�2q�0$,$*���.�+² {�o� (&3' ^�* !2%!�$4+<(H> 2+$*+<(* %$4+��£�(2�2�$4 %�Q�/2!��#S)P!3(: +$#/+B�,!��4 (C"�£-��=­:� �M¨M¨*�(®%�"&m¤C���=¥ ¨ � ®°­[¥H¨M¨@�L¥ 46¦(¥r®����j¦(¯�#1��� �j¬;¥�¨[­ �D¨��[¬;­[®°¥ �B#1���1�/¨[­&¨@���M¨[�o)L�(�6 +�

y�w/y � y?u�u � d �(�Q3'+.-��)(:�6-D��«RC �}CZ� w : y �F2!(*��<� %$ w i6i(� C � �=A;E ���8�HA��}Ctvu0y�i0z �C �YC��m %!P#O��-3-DC�J��-Y�Q>;�=(: %#T�*<� ;(&$Q!��4(H�1��$4(,3?>R�C+<(,3R�*�('%(H�e�($4 [:£+B#S)P�. %#$ 0-�(* %2B2%$V>;)3(:� � E� !2M3x:-'+.2%�(��$* %)���$=(/� � +<-L�(��7C %)���$4(%� *$*�m�4 !2!( �0y?�?u � AP7-�6�£-�(* %$*-��)(:+<�6-L�(���*@� !-��.� ��($Q\j���J�0�.+B'>�($*-'+��P�

� 2@(:��<� %$ w i�i(y C � ��$ ���$20+��(� 1 �4 � -P�B>���� � � �67 �ICtvu �(�0z �C �YC!�{ %!�#S��-'-�Ce#1��� �j¬;¥�¨[­ � �.¨[¯Z¦(¥�¨*� �.®�¤���¤[C5-�G@ *$* +�,�%� �m [� �n��$Q\�x�)-�2S5 2�2'+B�*�6-x: d +�,�< +>��7{ %�(2'+.-P���@1�(�Q�&��2M3"!��4 !(4(&�%� w i6i(y C��=A � � � : u(�Pw : � ��0��!� : �RC

¸ � �

Page 207: Practical Architectures for Survivable Systems and Networks (Phase

tvu �xw%z �C �YC!�{ %!�#S��-'-�Cj5 $*2M3'+9(: !2!(&!P$* %����-P2Y'>�($,#S�(�x$4 %)�$4 %�4 0-�(M�)(*+.�6-P��'>�($��* !2%!�$4 �V>x�=(: +#S�+CNEo 02M3'-3+.2/�0�$* %)���$=(/� � +<-L�(�;7C %)���$4(%�!*$*�m�4 !2!( �(y?�xw ��AP7.�l�£-�(: %$4-L�)(*+.�6-L�0�§�(@� 0-��<�'��($Q\�;�J�(�.+Z'>��$*-'+��P� �F2!(:�(<[ +$w i6i!� C*�HAP9~$* +)[��$=( i � : �!� Ctvu ��umz �C �YC��{ %!�#S��-'-DCeA� 02+!�$*+9(H>^$*+B�,\"�m+<-�(&3' %#$ %$Q�6+.-��7+<-P'K$&�(�=(&$Q!'2!(,!�$* 0C �D¨��[¬;­[®°¥ �O®%� # ��[¨[­&¤ �P¦"�M¨��

I¨,¦(­ ®%�"&m¤�� �[��}­�&�� �� � � �%(� )L�0�6 %� �!�(� � � ��� �mg(!'-3 w i�i � C �=A � � � : w�� : �!�(�6ixw�� : & C d $4+<(Q:(: 0-�(: +�4(*+�#$�6-?>�'>��$F(&33 1�CEAjCoA� 0-L��(: � %$Q#O�)-' 0-�(kAx!�<�20��#T#$+<(*(* 0 B�6-£�£-?U6 +�4(*+��?�)(*+.�6-P� �0';(&33 A� 0-L��(: q�;��#S#$+<(4(: ! �6- � ��U6 +$*-�#$ 0-�(M�0�S5-�D��+B$,�+C �8$&�(�I(* %�4(*+�#$�6-?> +����6-�)L�(�6 +� w/� � : w(w�w �3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# �)-' +!�#O�)-'-��0�4 0-L�)(* i � C�3�(&#T�§Ctvu �(�0z �C �YC �m +!�#O�)-'-DC}�;��#S)P!3(: +$ �4 02%!P$*+<(H>�+.-1�/U�+��)(:+<�6-D²� �!��.-' +$&�(<3+��.+9(:+< %�%�'(,3�$* %�)(&�+�D��-P21$*+B�,\"�%C �£- �L¥H¨[­@�j¦(¥r®����j¦(¯D#1���1�/¨[­&¨@���M¨B����� ��®r¦(¥�®���� �N¦ �/¨[¥ �^¦���� �D¨��[¬x­ ®°¥ �O®%�£¥ ¨ � m¤[¥�#=¨@�L¥�¬;­ �´� � ®°¥H¨

f�m¬?¤�¨?#1���B�X®�¤M¤[®���� ��� �N¦ �/¨[¥ �1¦���� �D¨��[¬x­ ®°¥ �´�}¦���� � ¨��m­h&;¨ �{¦m¤ ®%�"&(¥\��� �o�L® �(¨[­&¤[®°¥ �0�og���-;:!L�($Q> w�� : w��Ow i6i!& C*3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$*+�Cµ2!��# �)-' %!P#O��-3-��(��+B$%Cv3�(,#S��Ctvu �0y(z �C �YC �m +!�#O�)-'-DC��;��#T)�!3(: +$V:]$* %���)(: +2�+<-P'K$&�(�=(&$Q!'2!(,!�$* S$*+��Q\"�I'>��$W'> %2' +$&�(�=�(�6 !-'20+< %�+C��£- �1¨,¦��#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥��1®%� �m� �(¨[­±�,�O¨@�L¥ � ¤O¥ ¨��e¬ %¯±®��A¦(¥5�.®�¤�� � �¨,¦(­ ®%�"&�� �D¨@�j¦(¥H¨ I¨,¦(­ ®%�"&

�� � � � �%-�� �� 4 � � � � � � � � � � �m�J)L�(�6 +� ��u � &0� � d �0�,3'+<-���(:��-D�}«RC¢�}CZ� w i @1�/> w i6i�0 C 1�CEAjC����U6 +$*-�#$ 0-�(%*$*+<-�(*+.-�� ���$20 0C 3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# �)-' +!�#O�)-'-��0�4 0-L�)(* i 0 C�3�(&#T��� �8$&�(�(: %�=(:+B#/�6-?>�+��H�6-{)L�(�6 +� � � u�u C

tvu � �mz �C �YC �m +!�#O�)-'-DC �; %$4(*+<(,!�2' ���-P2©$* !2!(:+9(&!�23 (C��£- �=­�� �M¨M¨*�(®%�"&m¤����{¥ ¨ � �+�+� �L¥�¨[­±�j¦(¥r®����j¦(¯#1���1�/¨[­M¨@���M¨$��� �.¨ � ¬;®°­&¨@�O¨@�L¥K¤ � �"&(®%��¨M¨[­ ®%�"&(�N)L�(�6 w��(� �ZA�2M3��(!�#R<� %$Q���D�H���<+.-'��+��%��g(!'-' u0����� C������� �;��#T)�!3(* %$mA��"20+< !(H>�Ctvu ���0z �C �YC �m %!P#O��-3-DC �H����!P�4(&$,�)(:+ZU6 �$*+��Q\"�P(:� (,3' )�!�<��<+.2 +.- (&33 ©!��* X�('G2!��#T)�!3(: +$~�Q>;�=(: %#T���-�2 $4 %����(: %2 (: !2M3'-'���<���(>��$+.-P2' [� (:� 7-�=A �fA 2/�(�4 %�%C Eo 02M3'-'+<2/�(�T$* +)[�($4(/�O�;��#T)�!3(* %$ A"20+Z: 0-'2! ^9F�0<[��$,�)(:�($Q>��ªAP7-�W�£-�(: +$*-L��(:+.��-L�(�§�*@� 0-��<� ��0$,\�=�J�(�.+Z'>��$*-'+��P� u(����� C1EG3' g#$���4(X$4 02! 0-�(U6 %$Q�*+<�6-�+��e��U0��+B���(<P�. C�6-x:]�.+.-3 }�)(='%(&)D² � �m'%(,)DCj2%�,��C��Q$*+�Cµ2!��#��m)�!�<��0!P�* %$Q���)-3 %!�#S��-'-���+����B!��4(,$&�)(*+BU� (Cv)��%�'%(&)D² � �m'%(,)DCµ2+�,��C��Q$*+§Cj20�(#��0)P!�<��0!��4 %$Q���)-' +!�#S��-'-��)+B���B!��4(,$&�)(*+BU6 0C�)j2P'��"��-P2�+.-O3�(,#S�'>��$,# '>��$�<�$4�o�.��:+.-��T�)(.3�(*(,)D² � �m�G�G�WCj2%�,��C��Q$*+�Cµ2!��#���-' %!�#S��-'- �)+��B��!��=(&$&��(:+BU� (Cv3�(&#T�§Ctvu � &mz �C �YC �{ %!�#S��-'-�C�EG3' W)[�)(: 0-�(*+��(�B�e�('o��)� 0-x:]<[�/�A�4��!�$420 �20�;2' +.-A23 +U6 +�.��)3+.-��Y$*�(<�!��4(.�V>;�4(: +#S�+C�£- �=­:� �M¨M¨*�(®%�"&m¤����1¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨x��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤£®%��R¨ �/¨@���M¨�� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤��=¬;­M¤[¬;®°¥m����# � �� �e$,!P�,�* +���+� �; %�B�6+�!P#��L5 )�$*+B� u0����� C

� 5*E �RCtvu ��00z �C �YC%�m +!�#O�)-'-DC 7{��<P!��4( -'�6-�)�$4��)�$4+. !(&�($Q> �4�('%(H�e�($* 0C �£- �=­:� �M¨M¨*�(®%�"&m¤ ����¥ ¨ � �+�+�

���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ ��¦���� �=­[® �m¦"���m��)��(�6 %� wou�u � wou(� � �6�(\"����-�2��~�J�(�<+B'>��$4-'+��x��@���>u(����� Cª������� �;��#T)�!3(: +$ A��"20+. @(H>�C 3�(*(,)D²����m�G�G�WCµ2+�,��C��Q$*+§Cj20�(#��)-3 %!�#S��-'-���+. 0 ! ��� C�)�� �)-�23�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# �)-' +!�#O�)-'-��)+< 0 0 ��� Cv)N2x'�C

tvu ��i0z �C �YC �{ %!�#S��-'-|��-P2��C �;�(!'2M3' %$+C~5�- [U(�0��!L�)(*+.�6-��('C(&3' ^�* !2%!�$4+<(H>~�(�,)� 02@(&�7�('{(&3' A5 $,#4>E� !2M3'-'+.2%�(��5}$42M3'+<(* 02!(,!�$* ��r5*EF56¡82'�"2%!�#$ 0-�(I2�$&�m'%(&�%CSE� !2M3'-'+<2/�(��$* +)[�($4(/���;��#T)�!3(* %$fA�20+< 0-'2! 9F�0<[��$,�)(:�($Q>��[AP7.�J�£-�(: +$*-L��(:+.��-L�(�§�j@? 0-��<����0$,\�a�J�(�<+B'>��$4-'+��x� u g��)-;!��($Q> w i6i�� C � +<-L�(�a$* +)[�($4(/�AP7-� *$*�m�4 !2!( &xw��(y : u(��� �x'>��$ 1�CEANCL5 $,#4>A�J��� ��@ � � ��$=(-@��6-�#$��!3(,3D���m [� g� +$,�* [>�C¸ � �

Page 208: Practical Architectures for Survivable Systems and Networks (Phase

tvu����0z �C �YC �m +!�#S��-'-D�N7�C°ANC �;��>6 +$%��7�C°gPC � !+. +$4(M�0��� �XC ��C�98 +U"+9(*(/�j��-P2�9*Cj7{��<3+.-��4�6-DCG5 �$4��U(�0<��B>A� 02+!�$* �8)[ +$&�)(*+.-��/A;>;�4(* %#{²eEG3' ��Q>;�=(: %#{�v+<(,� �0)�)��.+<2/�)(*+.�6-P�%���)-�2�)P$*�"�('K�%C�E� !2M3'-'+<2/�(�l$* +)[�($4(/��;��#S)P!3(: +$ A�20+< 0-'2! S9l�(<���$,�)(:��$V>��ZAx7-�.�£-�(: +$*-L�)(*+.�6-��(�§�l@? 0-��<�%��($,\�F�J�(�<+B'>��$4-'+��x�D@1�/> w i 0�� Cu -�2? %2DCZ�7{ +)[�($4( �HAP9�: w(w�� Ctvu��Pw%z �C �YC �{ %!�#S��-'-��vgPC � ����2�<� %$Q��� �YC �IC�9Z [U"+<(*(%�L��-�2?gPC IC d 0-P�,�. [>�C�5��=(&!�2x>��('l'r�(!��9(Q:b(*���. +$&��-�(20��#T)�!3(*+.-���C � +.-��(��$4 %)���$4( '>��$}5}7 j54�N58« &�� ��i!&0y ��A"(M��-x'>��$,2�7C %�4 /�($42M3£�£-��4(*+<(&!�(: (�a@� 0-��<�

��($Q\j�N�e5I��g(!��B> w i!&(� Ctvu��?umz �C �YC �m %!P#O��-3-��)-�2|9�C�9l�(#S)���$=(/C m+B��3��Z>�2' +)[ !-�2L�(<P�. A2'+B�4(&$4+�<�!�(: %2��V>;�4(: +#S�+C�Eo 02M3'-3+.2/�0�$* %)���$=(/�;�;��#T)�!3(* %$1A�20+< 0-'2! -9F�0<[��$,�)(:�($Q>��"Ax7-���£-�(* %$4-L�)(:+<�6-L�(���"@� !-��.� ��0$,\���J�0�.+B'>�($*-'+��P�6g(!3-'

w i 0�� C � +.-L�0�a7{ +)[�($4(/�L�;�6-�(&$&�)2!( �m��C«.58�*5 w�0 : 0xw : �}: �����?u �?'>��$ 1IC°ANCL5 $,#4>{�J��� �W@ªCtvu����0z �C �YC��m %!P#O��-3-Y��-�2Y«RC �}C ��($,\) %$%C[� �¥r¬'� �I����#1��� �j¬;¥�¨[­ª� %¬"¤�¨

� �m¯±¬��O¨ �;�%� �1� �m­±�T¦ �¥�®���� ��� �j¯.�m®°¥§¦(¥r®���� �I¦(¥§¦M¦m¤�¨[C AP7.� �£-�(: +$*-L��(:+.��-L�(�§�D@� 0-P�.� ��0$,\�F�J�(�.+Z'>��$*-3+��P� �Pw g(!��Z> w i 06i C� +.-L�0��$* +)[�($4(.'>��${AP7.� *$4�m�4 02@( � 0xwou � 1�CEANC � ��U6 +$*-�#$ 0-�(/Ctvu��(y(z �C �YC �{ %!�#S��-'-���-�2�«RC � C ��($Q\� +$%C 5 �Q!�#T#O�($V>L�('k20��#T)�!3(* %$A#$+��Q!��* �(: !2M3'-'+B�;!3 %�%C �£-

�e­:� �M¨M¨*�(®%�"&m¤�����¥ ¨ �e¨[¯ � ¥ 46¦(¥�®����j¦(¯f#1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ � #1���1�/¨[­&¨@���M¨[�G)L�(�6 +� �6i � � y?�!& ��J�(�<(*+�#$��$* 0��@��($Q>;���)-�2D� w�� � w�� �F2!(:�(<[ +$ w i 06i C � �=AxE ���}�HA��}C

tvu��!�mz �C �YC��{ %!�#S��-'-4��-�2I«RC �}C���($,\) %$+C'� �¥r¬3� �f���m#1��� �j¬x¥H¨[­ � %¬?¤�¨�

� �m¯±¬"�O¨ �e��¨��F#1��� �j¬;¥�¨[­� %¬"¤�¨ ¨�� �L® � ¬¨M¤[C AP7-�=�£-�(: %$4-L�)(*+.�6-L�0�§�L@? 0-��<� ��($,\�j�J�(�<+B'>��$4-'+��x�P7C +U"+��4 %2D� u @1�0$*2M3 w i6i�� C� +.-L�0��$* +)[�($4(.'>��${AP7.� *$4�m�4 02@( � 0xwou � 1�CEANC � ��U6 +$*-�#$ 0-�(/Ctvu�� �0z �C �YC �m +!�#O�)-'- ��-�2 �Cv54C ���$Q$&�(�+C ���x)[ +$*+< 0-'2! ��C+<(,3 ��@1��7-5}9F« (*� 2L�)(* (C �£-

�e­:� �M¨M¨*�(®%�"&m¤ ��� ¥ ¨ ��®°­&¤[¥ � � � 4 �� � �m­:��¤ � � ��� �L¥r­ ¬"¤[®���� �R¨[¥H¨��[¥r®���� ¦���� 4I¨[¥ ��;�m­�� � ���L®°¥£�m­ ®%�"&(� )L�(�6 +� &(� � 0�� �XAx��-�(M� �e���($&�P� �J�(�.+Z'>��$*-'+��P�q5 )�$*+B� w i6i6i C 1�AP�2� � �4C3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# �)-' +!�#O�)-'-��02' @( i6i C�3�(&#T�§Ctvu��!&mz �C �YC��m %!P#O��-3-D�!�IC��GC *$*�"2!(*��$%����-�2RE6C � C�9a!'-�(%C��$4 +U� 0-�(:+<-��W�* 02+!�$*+9(H>4#$+��Q!��* ;+.-423+��4(,$*+B<�!3(: +2�Q>;�4(* %#T�%C�Eo 02M3'-'+<2/�(�G$4 %)���$4(%�=�;��#S)P!3(: +$$A�20+< 0-'2! �9l�(<���$,�)(:��$V>��1AP7.�I�£-�(* %$*-��)(:+<�6-L�(����@� 0-��<�

��($Q\j�j�J�0�.+B'>�($*-'+��P��g(!'-' w i6i?u C��H�,�Q!' %21�(�-7{��#$ 69l�(<���$&��(:��$V>O$4 %)���$4(-7-9�:HE.7J: i?u : w���u �x7C��#/ 9F�0<[��$,�)(:�($Q>T� � 5 �}� �W$4+ �T�,��5 � � ��� w��(y(y�w : ��&(��� C��;�6-�(M��2@(G�*#/+B�.+< CA�+��0$,\�+. [�C+.2%�0�"�£-�(* %$4-' !(%²A�+��($Q\�+. +�C+<2%�%���W�HANC�7-9�Cv5 � C @���9*�L)�33�6-' �Pw�� : ����� : �?u0y�w C � ��$ ���$20+��(� 1-�* � -P�B>�Ctvu�� 00z �C �YC �m +!�#S��-'-���-�21E6C�7WC ��CN7-����Ce�*$,$*�(${2!��$,$4 02@(:+.��- 20�;2' +�-'>��$.<?>�(: :£��$Q�?��-'+B�0 %21�($*+9(&3�#$ !(*+.2)�$*�"20 +�,�*�($,�%C ������ ­Q¦��P¤%¦"�[¥r®����P¤k��� #1��� �j¬;¥�¨[­&¤[���: u0y � � ¡[² u�u�� � u(�?u ��@1�($*2M3 w i!&�� Ctvu��6i0z �C �YC��m %!P#O��-3-D�� %2'+9(:��$+C� 6��7.\;�Q3'��)T�M²( F +$*+9l,2/�)(*+.�6- d ��$,\"�,33��)DC[�I# � � � � � � ����� ¥u��¦(­&¨

� �"&(®%��¨M¨[­ ®%�"& 4 �m¥H¨M¤[� � � � ¡ ² y � y�& �'g(!��B> w i 0�� Ctvu &(�0z �C �YC��{ %!�#S��-'-D�´ +2'+<(*��$%C( 8��7-\"�,33��)4�Q�M²/ F %$4+<l,2%�)(:+<�6- d ��$Q\;�Q3'��)DC"�I# � � � � � � ����� ¥u��¦(­&¨

� �"&(®%��¨M¨[­ ®%�"& 4 �m¥H¨M¤[� � � � ¡ ² w � ��� �'g(!��B> w i 0Pw Ctvu &xw%z d C¢9*C �X� m +$*-D�8g($%CZ��(&�(�,\^'>��$*2! k2M3L�)+�$,#S��-DC-5�- ��)[ !-��Q>;�=(: %#T�6)�$4��2! %�,� '>��$8«F�?«RC.Eo 02M3'-3+.2/�0�$* %)���$=(/� �8)� 0- A;>;�4(: +#S�-E��(�,\ � ��$420 (��«F +'> 0-P�* kA�20+< 0-'2! �1�?�($,2�� � 2@(:��<� %$ w i6i 0 Ctvu &�umz �.Cv�MC �8$,�?��-3+.2M\C � ¨ � ¬;¯±¥r®��M¤ ���o¤[¥H¨@��� ��� � � ¦��X®%�j¦(¥r®���� ��� ¥K¤ �¥r­ ¬v�[¥r¬;­M¨[Cq@��HE *$4 %�,�+��J�(#R<�$4+�2��6 0�@1�(�Q�&��2M3"!��4 !(4(&�%� w i!&�u C

¸ ���

Page 209: Practical Architectures for Survivable Systems and Networks (Phase

tvu &(�0z gPC �XC �6!P�4(: +$,3'�(!3(/��gPC �XC098 +U">��"�)-�2 �}C �}C d +�.2M3DCxEG3' CAP�0'> :HEH2+�x�4 02%!P$*+<(H>I#$�x2' +�§C"�£- � �j­ ®%�"&;¨[­ �� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥°¤I¦���� �D¨��[¬;­[®°¥ �m�)L�(�6 +� u;w�& � u(�0y � w i�i 0 C

tvu &0y(z ANC �}�.$* 0�6gPC�7.!��Q3;<?>(� �IC Ax3L��-�\m�($+�m��-�2 � C%U��6- { 0-�\) (C � ��$Q#O�0�0U6 +$*+9l,2/�)(*+.�6-8'>�($�'r�(!��9(Q:b(*���. +$&��-�(�($*2M3'+9(: !2!(&!P$* %�+² *$*���< %�6��#$ 0-���(*� (&33 �2' +�*+B�6-L�(' *  ANC ������ ­Q¦��P¤%¦"�[¥�®����P¤���� ����� ¥u��¦(­&¨� �"&(®%��¨M¨[­ ®%�"&(� uxw � u ¡[² w��!& � wou � � � %<�$Q!L�($V> w i6i!� C�Ax)� 02!+��(�"�* !2!(*+.�6-I��- � ��$,#S�(�;@� @(&3'�;2�����!P$*��)� � i�� C

tvu & �mz «RC �}C ��($Q\� %$+C �*®9& ¥�®%�"& #1��� �j¬;¥H¨[­/#�­ ®%�O¨[CDg��(3'- d +B�. [>�� A"�6-��%���{ +� �n�($,\� w i6i 0 Ctvu &��0z E6C�5IC ��0$,\� +$%C5©�4 02%!P$* .�*!�$*�()[ %��-X�Q>;�4(* %#�'>�($��()�)P�.+.2%�)(:+<�6-��Z+.-R�}#R!��9(:+Z:§U6 !-�2'��$� 0-?U"+�$*��-�#/ !-�(�rEG3' �AP�nAx56@��-*$*�o�4 02!(M¡[CD�£- �=­�� �M¨M¨*�(®%�"&m¤ ���-¥ ¨ ���m¬;­ ¥�¨M¨@�L¥ 4W¦(¥r®����j¦(¯o#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥��#1���1�/¨[­M¨@���M¨[�x)L�(�6 +� �(�!� � �;w�� � d �(�Q3'+.-��)(:�6-D��«RC �}CZ� w � y �F2!(*��<[ +$ w i6iPw C � �=AxE � �8�HA��}Ctvu & &mz «RC¢9*C ��($4-L�(�+C �F-?(&3' 2%$4+<(: +$*+��7(*�O<� I!��4 %2 +<-12' !20��#T)����*+<-��S�V>;�4(: +#S�m+.-�(:�S#/�;2�!��< %�+CB#1��� ��X¬��L®��,¦(¥r®����P¤I���W¥ ¨m�I# � � w�� � wou ¡[�L«F !20 %#4<[ +$ w i!&�u Ctvu &�00z «RC¢9*C ��($*-��(�%C�5�(: !2M3'-'+B�;!3 Y'>�($}�*�0'%(H�J�($4 X#/�;2�!��< 4�Q)[ !20+<l'2/�)(*+.�6-��C+9(&3� [�P�(#T)��< %�%C?#1���B�X¬ ��L®��,¦(¥�®����P¤I���W¥ ¨m�I# � � w�� � � ¡[�@���> w i!&�u Ctvu &�i0z «RC¢9*C2��0$*-L�(�+C �F-©���Q<�!��+�+�1��$,2P��² m+< %$,�($*2M3'+<2/�(�G�=(&$Q!'2!(,!�$* 0C �£- �1� �m­±�T¦(¥r®������=­:� �M¨M¤M¤[®%�"&

� " �=­:� �M¨M¨*�(®%�"&m¤B���I¥ ¨ � � #1���"&(­M¨M¤M¤ +- �%&m�LU�����!�#$ kA��('%(H�e�($* 0��)L�(�� %� �(� � � ����i C��m��$=(&3x: m���B����-�2��P5}#T�4(* %$Q2L�(#{� w i!&0y C

tvu�0��0z «RC¢9*C ��($*-��(�%CREG33 $+<-P�L!' !-'20 7�('��4�('%(H�J�0$* Y�4(,$,!'2@(&!�$4 $��- $4 %�<+��(<'+B�.+9(H>�C8�£-��=­:� �M¨M¨*�(®%�"&m¤����R¥ ¨ �L¥H¨[­@�j¦(¥r®����j¦(¯n#1���1�/¨[­&¨@���M¨$����.¨[¯±®r¦%¯�¨ ����� ¥h��¦(­&¨[��)��(�6 %� �!��0 � � �?u �j5})�$4+�� w i!&�� C87C %)�$4+.-�(: +2�C+<(&3�+B#S)�$4��U6 %#$ 0-�(,��+<-I7WC �n +3D��#�¬;­ ­M¨@�L¥ ­&¨@���m¤�®%� �=­:�*&(­,¦��B�X®%�"& � ¨[¥ �0�"�m¯.�*& � ���$4 0-�(:+<20 : }�(�B�§� w i!& & � w�w�w � w(w i C

tvu�0Pw%z «RC¢9*C ��($4-L�(�%C � -5(,3' 82' +�*+B�6-^��-�2A2' [U6 +�.��)�#$ 0-�(H�0'�)P$*����$,�(# 'r�(#$+��.+< %�+C ������ ­Q¦��P¤%¦"�[¥r®����P¤��� ����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(�,AP��: u � w ¡ ² w � i �@1�0$*2M3 w i!&�� Ctvu�0?umz «RC¢9*C ��($4-L�(�%C8@1�)(,3' %#S�)(:+<2/�(�l2' +�*2+$*+�)�(:+.��-��8��-P2��,)� 02!+<l,2%�)(:+<�6- �('��*�('%(H�e�($* 0C8�£- �=­:� �M¨M¨*�(®%�"&m¤���W¥ ¨ � � � �m­ ¯9� #1���"&(­&¨M¤M¤�+-+-�3� � �m¯±¬"�O¨ ��)��(�6 %� �!�my � �!��i CP� � � F�L5}!���!P�4( w i6i(y Ctvu�0��0z «RC¢9*C���0$*-L�(�+CoA��('%(H�e�($* { 0-P�6+.-' ! %$4+.-���²�5�-T!'-'2!�6-��,!P#S#S�)(: +2O#S�($,$4+��(�� (C1#1���B�X¬��L®��,¦(¥r®����P¤F���¥ ¨��I# � � y?� � i ¡[² wou�0 �'A� %)�(: %#4<[ +$ w i6i!& C �P¤[®u�;¨ �.®�¤���¤;20���B!�#$-DCtvu�0(y(z «RC¢9*C2��0$*-L�(�+C EJ�;��)[���4+<(*+.�6-��B��-q�.+<20 !-��*+<-���C|�£- �=­�� �M¨M¨*�(®%�"&m¤ ���A¥ ¨ � �+�+� �L¥�¨[­±�j¦(¥r®����j¦(¯#1���1�/¨[­M¨@���M¨������.¨ � ¬;®°­&¨@�O¨@�L¥K¤ � �"&(®%��¨M¨[­ ®%�"&(��)��(�6 %� w��0y � w�� � ��A�2M3L�0!�#R<� %$,�P���H���<+.-'��+��%�og(!3-' u(����� CP������� �;��#T)�!3(* %${A��"20+< !(H>(Ctvu�0!�mz «RC¢9*C ��($*-L�0�%� FC �}C-�e�< %#$ 0-�(&�+�6��-�2�«RC¢@ªC d 0+��Q�%C EG3' #$�x2�!P���($S�4(&$Q!'2!(,!�$* x�(' 20�(#S)��< [��Q>;�4(* %#T�%C ������ ­Q¦��P¤%¦"�[¥r®����P¤���� ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(��AP��: w�w � � ¡ ² u �)i � u�� � �;@1�($*2M3 w i 0!� Ctvu�0 �0z «RC¢9*C ��($4-L�(�W��-�2 �XC }��-�2P�0 %��C�@���$4 I�6-��,)� 02!+<l,2%�)(:+<�6- (* 02M3'-'+B�"!' %�6'>��$ �*�('%(H�e�($* X#$�;2�!��. +�%CE� !2M3'-'+.2%�(�L$* +)[�($4(/� � �)2M3;<� %$4 0+<2M3S�£-P'>�($,#S�)(:+B\j�0E� !2M3'-'+B�*2M3' m�"2M3��*2M3"!��< -«6�($,#T�4(&�(23(/�(7{ +�* %�($*2M37{ +)[��$=( �HAA� & � � w � � %$Q#O��-?>(�L5})�$4+�� w i & � C

¸ �´¸

Page 210: Practical Architectures for Survivable Systems and Networks (Phase

tvu�0!&mz «RC¢9*C2��0$*-L�(�+�CgPC=@1�(2' [>��.��-P2©@ªC��H���< +�.�Q\"+�C *$* !20+B�* 123��2+!�#/ !-�(M�)(*+.�6-p�('}�1 %�B�Z:]�4(&$Q!'2!(,!�$* +2)�$*���($&�(#T�%C ������ ­Q¦��P¤%¦"�[¥r®����P¤���� ����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&(� u0� � wou ¡[² i(y!0 � i &�� �G«F !20 %#4<[ +$w i6i(y Ctvu�0 00z «RC¢9*C ��($4-L�(����-�2 d C¢7WC *$*+<20 0C�EG3' G2' +�*+���-I�(',(&33 eU"+�$4(,!L�(�;#/ +#/�($Q>I�(�,)� 02@(&�ª�('j�-U�+B$4(,!L�(�;#O�m:2M3'+.-' 0C��£- �=­:� �M¨M¨*�(®%�"&m¤F���.¥ ¨;�I# � � �D� � # � � � � � ��� �m­���¤ � ����� � ®°­ ¥r¬�¦(¯o#1��� �j¬;¥�¨[­

���o¤[¥H¨@�4¤[C�5-�G@ª�N@1�($42M3 w i &(� Ctvu�06i0z «RC¢9*C ��($4-L�(�W��-�2�«RC¢9*C�A�+. [�C+.��$4 %\C 1 �4 B�('ª(&33 I20�6-320 %)�(��('ª(&$,��-��,)��($* !-'2+> +.- (,3' R2' +�*+���- �('3'+. +$&�($42M3'+.2%�(���Z>��=(&$Q!'2!(,!�$* +2ª�V>x�=(: +#S�+C�#1���B�X¬��L®��,¦(¥r®����P¤$���R¥ ¨f�I# � � w�0 � & ¡[² y?�Pw � y�� 0 ��g(!��B>w i!& � Ctvu�i��0z gPC ��(!��§C �e!P���5+.-p(&3' �)�$*�(��$&�(#{C Eo 02M3'-'+<2/�(� $* +)[��$=(/�G7C %)���$=(g<?> (&3' �A;!�<[2!��#T#/+9(*(: ! G�6-�£-"U� %�=(:+����)(:+<�6-��{��-�2 �}U6 %$Q�*+B��3�(��0'k(&33 ��;�(#S#$+<(4(: 0 �6-SA"20+. !-'20 0��Ax)L�)20 ª��-�2 E� !2M3'-'���<���(>(�

1IC°ANC m��!P�* �('�7C %)P$* %�4 0-�(M��(:+BU� %�+� w i�i�� Ctvu�iPw%z 9�C ��0!����4�6-DC @� 02M3���-'+��! %2�)�$4���0'K�-'>��$ �S$4 02+!�$,�4+BU6 R�(!3(&33 0-�(:+<2/�)(*+.�6-{)�$*�)(:�"20����CG�£- ��m¥ ������#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ �5�o�m¬����?¦(¥r®����P¤ � �m­:��¤ � �j�m)��(�6 %� 0(y � i!� C+���������;�(#S)�!�(: %$oA"��2!+. !(H>(� w i6i!& Ctvu�i?umz 9�C ��(!��B�*�6-DC *$*��U"+.-��|)�$4��)[ +$4(*+. %�G�('4�* !2%!�$4+<(H> )�$4��(:�"20���B�^<">X+<-�2�!'2@(:+<�6-DC �£- ��m¥ ������#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ �5�o�m¬����?¦(¥r®����P¤ � �m­:��¤ � �j�m)��(�6 %� &(� � 0�� C+���������;�(#S)�!�(: %$oA"��2!+. !(H>(� w i6i!& Ctvu�i��0z @ªC�� %�(�* 0�N7WCvAx33���4(&�(\���-�2�9�C�9F�0#S)���$4(%C�7C /��2M33+.-��T�(��$4 0 +#/ !-�({+<-G(,3' 6)�$4 %�* !-'20 f�('F'r�(!��<(,�%C!v�m¬;­±�j¦(¯����6¥ ¨��I# � � u & � u ¡ ² u�u 0 � u(�(y �x5 )�$*+B� w i 0�� Ctvu�i(y(z �IC)� ! %�.+<-����)-�2~7WCaE��/>;�.�($%CGA"(&��-�2L�0$,2��6�£#4>�(&3P�%��23 %��!P�*+.��-��4�)-�2���)P)[��$=(&!'-3+<(:+< %�+CO�£-��=­:� ��M¨M¨*�(®%�"&m¤����X¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨/��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬,�[¥K¤T®%���R¨ �/¨@���M¨� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤ �e¬;­&¤[¬x®°¥H���$# � �� �e$Q!��,�4 %�B�%� �; +���6+B!�#��x5})�$4+�� u0����� C � 5*E �RCtvu�i!�mz 7�C o %$Q��#S��-DC 4�¨[¥h�;�m­:� 3D¦ �"¨[­ �=­:�m¥\� ���m¯¢¤B�*®°¥ � � ��¦��L¥r®%��¨ �C��%¬"¤[¥u��¨M¤M¤[C *3L« (&3' +�*+��+��@{�HE6��J�(#R<�$4+�2��6 0�@1�(�Q�&��2M3"!��4 !(4(&�%� w i 0 0 Ctvu�i �0z IC � @(: %$Q�* !-Y��-�2X@ C(@?+.2M3' +���%C �F-4�4+��6-��)(&!�$4 =�42M3' %#$ %�F�C+<(,3f(&3P$* %�Q3'���B2IU6 +$*+9l,2/�)(*+.�6-�2' @(: 02@(:+<-��#O�(�<+.2!+.��!���U6 +$*+<l' %$,�+C��£- � �j­ ®%�"&;¨[­ � � ¨[­[¯Z¦ &�� �}¨[­[¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤^®%�S#1��� �j¬x¥H¨[­ ���[®§¨@���M¨��

�D¨��[¬x­ ®°¥ � �=­:�m¥\� ���m¯¢¤����=­:� �M¨M¨*�(®%�"&m¤���� � ¥ �L¥H¨[­±�j¦(¥�®����j¦(¯ � �m­:��¤ � �j� )L�(�6 +� �!& � & & ����($4+��%�� $,��-'2! (�L5})P$*+�� w i6i!& Ctvu�i!&mz IC o !(,$*���Q\"+�C � � �"&(®%��¨M¨[­e®�¤ }¬��T¦�� � � ¨ �C�m¯�¨������l¦(®°¯±¬;­&¨G®%� �¬v���M¨M¤M¤ � ¬;¯��R¨M¤[®9&��LC'A"(/C�@1�($�:(:+.-���� *$* +�,�+� �{ +� �n�($,\� w i 0!� Ctvu�i 00z IC!o !(&$4���,\�+�C �4¨M¤[®9&����J¦(­,¦��(®9&��4¤�� #�¦m¤�¨ 8®�¤[¥£�m­ ®§¨M¤ ��� � ­[­:�m­ ¦���� !;¬3� &��O¨@�L¥F®%� � �"&(®%��¨M¨[­ ®%�"&(C�J�(#R<�$4+�2��6 '1{-'+BU� %$Q�*+<(H>,�$4 %�Q�%�N�J�(#R<�$4+�2��� (�L�ª-�������-�2D� w i6i(y Ctvu�i6i0z IC��'> 0+Z'> %$%�m«RC´A"2M3"�C+< %$+����-�2 � C d C/U6�6- m !-�\� 0C � �($,#S�(�0U� %$*+9l,2/��(:+.��-W'>�($�(:+�#$ [:�(&$4+����6 +$* +2F2%�<��2M\�Q>"-'2M3�$4�6-'+��%�)(:+<�6-DC��£- �=­:� �M¨M¨*�(®%�"&m¤k���6¥ ¨ +-+-+-�#1���1�/¨[­&¨@���M¨f��� �R¨ �L¨@���?¦%¯�¨B#1��� �j¬x¥r®%�"& � �m­#�­[®°¥r®��,¦(¯v� � �j¯±®��,¦(¥�®����P¤[�P)L�(�6 +� w i�� � uxw�u �,AP�)- g����4 (�j�J�(�<+B'>��$4-'+��x�'g���-"!L�0$Q> w i�i 0 Ct �����0z �}C FC ��, 0 +�6 %$+C �D¨��[¬x­ ®°¥ ��®%� #1��� �j¬;¥r®%�"&(C *$* !-�(*+.2! [: �(�������ª-����< +�1���;2��e�<+B�N�%� �{ +� g� %$Q�* +>(�

w i6i � CªA� 02!�6-�2 +2'+<(*+.�6-�C¸ ��

Page 211: Practical Architectures for Survivable Systems and Networks (Phase

t ���Pw%z ANC¢9*C ��, ! %�6 +$%C ����� ¥h��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&+� � ¨��m­ �{¦���� �=­Q¦"�[¥�®��M¨[C *$* 0-�(*+.20 : �(�����D�ª-����< +�1���;2�e�.+B�N�%� �m +� g� %$Q�* +>(� w i6i 0 Ct ���?umz @ªC ����B�.+<(4(/C��=>;<� %$=(: %$Q$*��$4+��Q#�² � ��2!({��$G'r��-32+> ���£-�=­�� �M¨M¨*�(®%�"&m¤k���I¥ ¨ 4}®%��¨[¥�¨M¨@�L¥ 4W¦(¥r®����j¦(¯#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥�� #1���1�/¨[­&¨@���M¨[�e)L�(�� %� u 0!� � u�0�i � �J�0�<(:+B#/�($* (�e@1�($V>;����-�2�� � � w�� �F2!(:�(<[ +$

w i6i!& C � �=AxE ���}�HA��}Ct �����0z �Cv54C���($,$&�0�%CZAxEF5*E6²"5aA"(M��(: .EG$&��-P�*+<(*+.�6-Y5m-L�(�B>;�4+���EH���(�P'>��$D+.-�(&$Q!��*+<�6-Y2' !(* 02@(:+.��-DCa@1�0�4(: +$%�v�(&3' +�*+��+�*�;��#T)�!3(* %$kA�20+< 0-'2! g«F +)L�($4(,#/ !-�(/� 1{-'+BU� %$Q�*+<(H>x�('G�J�(�.+Z'>��$*-3+��P�oAP�)-�(&���J�0$,<L�($,�P��g(!��B>

w i6i?u Ct ���(y(z �Cv54C o��$,$,�(�W��-�2 �C �XC �m +!�#O�)-'-DCI�=@���7.589l«R²l��U6 !-�(R@?�6-'+<(*��$*+<-��A�ª-L�(<P�.+.-P�A7{ +�,)��6-��4 %�(:��5�-3��#O�0�.��!��S98+BU� �«F+��=(&!�$Q<L��-'2! %�%C��£-��=­:� �M¨M¨*�(®%�"&m¤����1¥ ¨ 48®%��¨[¥H¨M¨@�L¥ 46¦(¥�®����j¦(¯f#1��� �

�j¬x¥H¨[­ �D¨��[¬;­ ®°¥���#1���1�/¨[­&¨@���M¨[�L)L�0�6 %� �!�(� � ���!� � �J�(�9(:+�#$��$4 (�@1�0$Q>;����-P2D� u�u : u�� �F2!(*��<� %$ w i6i!& C� �=AxE ���}�HA��}C

t ���!�mz �Cv54C���($,$&�0�=�)-�2Y54C( ��(�B2' %�+C�98+ZU6 e(&$,� �$2-��-L�(�Z>x�4+�� �0'�E-� �0� ~�?��(: +�e�/>;�%C��£- �=­:� �M¨M¨*�(®%�"&m¤����¥ ¨ ���)� �,��¤[®°¬"� ���4�¨[¥h�;�m­:�{¦���� �W®�¤[¥r­ ® %¬x¥H¨*� ����¤[¥�¨@� �D¨��[¬;­[®°¥ �mC��£-�(: +$*-' @(fA���2!+. @(H>��l@1�0$*2M3w i6i 0 C

t ��� �0z «RC *$,�(�&�(2�C �R¨ �L¨@���?¦%¯�¨ ����¤[¥�¨@�4¤ �L¥�¨�&(­Q¦(¥r®���� �a¤[®%�"&1¥ ¨ � ¨��m­[®§¨M¤���� � ¨,¦m¤[¬;­M¨@�O¨@�L¥8¦�����R¨��[®�¤[®����G���j¦(¯ ��¤[®�¤[C *3L«N(,3' %�4+��%�j«F +)L�($4(,#/ !-�(��('*�;��#T)�!3(: +$mA�20+< 0-'2! (� 1m-'+ZU6 %$Q�*+9(H>��0' �n��$Q\j�5}!���!P�4( w i6i 0 C

t ���!&mz «RC��$,�(�&�02���-�2 gPCj@�2/«F +$,#$+�2DC=«F %)� 0-P2L�(<'+B�.+<(H>� +U0�(�B!L�)(:+<�6-^!��*+<-��S�T#R!P�<(:+ :£2+$*+<(* %$4+��I23 020+B�*+<�6-��-L�(�Z>x�4+��G)�$4��2! %2�!P$* (C��£- �S¦ � �L¨,¦(­ � w i6i6i Ct ��� 00z �IC��.C �$4��2@(:��$+CWEG3' Y$* %�=(&$4+.2!(* %2£��2!20 +�,�W)�$*�"20 +�,�4��$%²85m-� [�P�(#T)��. I�0'�'>�($,#S�(�FU� %$4+<l,2%�)(:+<�6-DCW�£-�e­:� �M¨M¨*�(®%�"&m¤5���T¥ ¨ +-/. � ���)� �,��¤[®°¬"� ��� �D¨��[¬;­[®°¥ ��¦���� �=­ ® �m¦"���m��)L�0�6 %� y�i � ��� � �6�(\"����-�2D��e54�L5})P$*+�� w i 0!� CP������� �;��#T)�!3(* %${A��"20+< !(H>(Ct ���6i0z �IC��.C *$4��2@(:��$+C A� /�m F+. [� '>��$Q#O�0�}�,)� 02!+<l,2%�)(:+<�6-��+C E� !2M3'-'+<2/�(�W$* +)[�($4(/�8�;��#T)�!3(: +$?A�20+< 0-'2! 9F�0<[��$,�)(:�($Q>��,AP7-���£-�(: +$*-L�)(*+.�6-��(�§�@? 0-��<� ��($,\�N�J�(�<+B'>��$4-'+��P�"5 )�$*+B� w i6iPw Ct �Pw��0z �IC��.C �$4��2@(:��$R��-�2��C �XC �m +!�#S��-'-DC£5}$42M3'+<(* 02@(&!�$,�(�;+B#S)��<+.2%�)(:+<�6-����('C20��U� %$4($2M3L�)-'-' %�B�%C �£-�e­:� �M¨M¨*�(®%�"&m¤m���J¥ ¨ ��® � ¥H¨M¨@�L¥ 46¦(¥r®����j¦(¯8#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥��/#1���1�/¨[­&¨@���M¨[�()L�(�� %� u�0 � y?� � �e�(�Z:(:+�#$��$4 (�"@1�0$Q>;����-P2D� w�� � w�� �F2@(:��<� %$ w i6i�u C3�(4(&)D² � �m�G�G�WCj2%�Q�§Cv�,$4+§Cj20��# �)-' +!�#O�)-'-��)-'2+� i?u C�3�(&#T�§Ct �Pw�w%z �}C7 �)-�2' %�B�§CDA">x�=(: +# 2' %�4+��6-{��-�2{�4(,$,!'2@(&!�$4+.-��PC�#1��� �j¬x¥H¨[­ !v�m¬;­±�j¦(¯±� u�i � y ¡[² ����� � ��� � � w i 0 � Ct �Pwoumz �}C�7-��-�23 %���F��-P2�gPC¢�GCN«F��<��4�6-DC-7{ +�.+��(<'+��<+<(H>O��-�2��4 02+!�$*+9(H>�+B�,�Q!' %�F+<-12'+B�4(,$*+�<P!3(: +2 20�(#S)�!�(:+.-P��Q>;�4(* %#T�%Ce�£-�=­:� �M¨M¨*�(®%�"&m¤I���W¥ ¨ �*® � ¥ ����� �,��¤[®°¬�� ��� �-¨[¯±®r¦%®°¯±®°¥ �T®%� �W®�¤[¥�­ ® %¬;¥�¨*� ����� ¥u��¦(­&¨¦���� �I¦(¥§¦M¦m¤�¨ ���o¤[¥H¨@�4¤[�L98���.5�-P�6 %�< %�%�j�J�0�.+B'>�($*-'+��P�'g��)-;!��($Q> w i 0 � Ct �Pw��0z �}Co7 �)-�2' %�B�§�)gPC :V�}Cm9l�()�$*+< (�� IC � ��)� !(,�(�(��-�2 �}Co98+<(*(,�. [�;�"�x2��� +2'+<(*��$,�+C �=­M¨*�(®��[¥§¦%¯ �5�4¨ �L¨@���?¦%¯�¨#1��� �j¬x¥r®%�"& ����¤[¥�¨@�4¤[C �J�0�*+.2�7C %�4 /�($42M3�A� +$*+. +�%C�Ax)P$*+.-P�6 %$�:] D %$Q���(�P� �; +$,�<+.-D� w i6i!� Ct �Pw/y(z E6C¢7WC ��CD7-����C � ­ ­:�m­ � #1���L¥�­:�m¯1#1�0�(®%�"& � �m­�#1��� �j¬x¥H¨[­ ����¤[¥�¨@�4¤[C �$4 0-�(:+<20 : }�0���§�N�ª-����< +�1���;2�e�.+B�N�%� �m +� g� %$Q�* +>(� w i 06i C

¸ ���

Page 212: Practical Architectures for Survivable Systems and Networks (Phase

t �Pw��mz @ªCL7-��>"-L�0�§CF5S2/�(�4 6�4(,!�2P>��('F�0��$* ! %#$ 0-�(.)�$*�(<��. +#S�1+.-g2'+B�4(,$*+�<P!3(: +2A�Q>;�4(* %#T�%² �m�6-;:H<��<��2M\�+.-P��)(:��#$+.2�20��#T#/+9(&#$ 0-�(/C*�£-�=­:� �M¨M¨*�(®%�"&m¤I���W¥ ¨ +-+- }®9& � �}¤M¤[¬x­Q¦����M¨ ����¤[¥�¨@�4¤ � �"&(®%��¨M¨[­ ®%�"&� �m­:��¤ � �j��)L�0�6 %� u(�6i � uxw/y � d �0�,3'+<-���(:��-D�L«RC¢�}CB�L5 !���!��=( w i6i!& C�������� �;��#T)�!3(* %${A��"20+< !(H>�Ct �Pw��0z «RC¢«RC�7{ +2' %�B�§C 46¦��X®%�"&�¦���� �=­��m¥H¨��[¥r®����q®%� ��� ¥H¨@���(® %¯�¨ ���L¨[­,¦(¥r®%�"& ���o¤[¥H¨@�4¤[C �3�« (,3' %�4+��+�

1m-'+ZU6 %$Q�*+9(H>��('��J�(�.+Z'>��$*-'+��P� w i!&0y Ct �Pw�&mz «RC¢«RCP7{ +2' %�B�a��-�2{7WCEANC � �0<�$Q>(CDA� %�< 02@(:+BU� W$* +U���2%�)(:+<�6-��('�2/�()��(<'+��<+<(*+. %�+C��£- �=­:� �M¨M¨*�(®%�"&m¤k���6¥ ¨ �L¥H¨[­@�j¦(¥r®����j¦(¯ � �m­���¤ � � �����=­:�m¥�¨��[¥r®�����®%� ���L¨[­Q¦(¥�®%�"&�����¤[¥�¨@�4¤[�F)L�(�6 +� w i & � u(�6i �F5 !���!��=(w i!&0y Ct �Pw�00z @ªCD7C 0+9(: %$8��-�2 �XC �;+B$,#S��-DC m���N(*�g�* !2%!�$4 %�Z>�$* +)��.+<2/�)(* 4�4 %$QU"+<20 %�+CI�I# � ­Q¦��P¤%¦"�[¥�®����P¤7���

�e­:�*&(­Q¦��B�X®%�"& 3D¦��"&(¬P¦ &;¨M¤I¦���� ����¤[¥�¨@�4¤[� w � � � ¡ ² i�0 � � w��(�6i �P@1�/> w i6i(y Ct �Pw i0z gPC 7{+< %�B> ��-�2 @ªC m !-'-' %�Q�Q>(C EF$,!��=( ��-P2 )L�0$4(:+��(� (H>;)'+<-�� +<- �()[ !- �V>x��:(: %#T� �(' #$��<'+B�. �(�6 0-�(,�%C E� !2M3'-'+.2%�(� $4 %)���$4(%� 1m-'+ZU6 +$,�*+9(H> �('�Ax!P�,�* �N� g(!��Z> w i6i 0 C'%(&)D² � �m'%(,)DCµ2!�����+C��Q!��V�NC���2(Cv!�\ �0)�!�< �0$* +)[��$=(&� �)20��#T)��420+���2%� �0y�i 0 Cv)��%C � Ct �?u(�0z gPCN7C+.�($,2L��-{��-P2 �}C�A�2M33-' 0+< %$%C.�ª-?U"+�$4�6-�#$ 0-�(M�(�a\) +>��6 0-3 %$&��(:+.��-G(*���J�($Q2 2%�B!' %�< %�Q�}�(�� 0-�(&�+CJ�£-

� �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤I®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��1&;¨@�L¥°¤R¦�����D¨��[¬x­ ®°¥ �0�L)L�0�6 %� w�� � u0y � w i�i 0 C

t �?uxw%z 7�CP7{+ZU6 %�=(-��-�2 �}CP9F�0#S)��4�6-DC AP«�Ax���O�R�*+�#T)��< }2'+B�4(&$4+�<�!�(: %2A�4 02+!�$*+9(H>5+.-x'K$&�(�=(&$,!32!(&!P$* (C�E� !2M3x:-'+.2%�(�G$* +)[��$=(/�J@��HE 9l�(<[�($&�)(*��$Q>~'>�($O�;�(#S)�!�(: %$�A�2!+. 0-320 (� u(����� C| D %$Q�*+.��- u C � +��T�/U(�)+����0<��. �6-x:H�<+.-' T3�(*(,)D²�����(&3' !��$Q>(C��<2%�+C�#$+<(%Cµ +2�!���� 2!+�� �0�,2��4+§Cv3�(&#T�=�0�.�6-��{�C+<(,3P��(&33 %$R2'�"2%!P#/ !-�(&�)(:+<�6-~�)-�2�*��!�$420 20�;2' (Ct �?u�umz 9�C;7C��<'+<-��*�6-O��-�2 �YC �IC;98 +U"+9(*(/C �$4���0'�(: !2M3'-'+��"!' +�e'>��$�3'+< %$&�0$*2M3'+<2/�(�B�B>R�=(&$Q!'2!(,!�$* +2A)�$*���($&�(#T�%C#1���B�X¬��L®��,¦(¥r®����P¤k���W¥ ¨��I# � � u(� � y ¡[² u &xw � u 0�� �P5 )�$*+B� w i!&�& Ct �?u(�0z 9�Cm7C��<'+<-��*�6-�� �XC �ICm98 +U"+<(4(/�0��-�2 � C�5IC6A�+B�BU� %$,<� %$Q��C � ¨ � � W¦����@� � �mC;�;��#T)�!3(* %$�A�20+< 0-'2! 9F�0<[��$,�)(:�($Q>��,AP7-���£-�(: +$*-L�)(*+.�6-��(�§�@? 0-��<� ��($,\�N�J�(�<+B'>��$4-'+��P��g(!'-3 w i &�i C�EG3�$4 0 W D����!P#/ +�%Ct �?u0y(z gPC�5IC"7{�"2M3��.+B�*��-�2O@ªC d C"�ª+.2M3'+<-DC d +9(&3Y#$+.2%$4���*2!��)� .��-�27(H�; ! %�0 +$,�+²�EG33 d �($,#�'K$4��# @��HE6�v�)[ +$,�,)� 02@(:+ZU6 (Cf#1���B�X¬"�L®��,¦(¥�®����P¤f���W¥ ¨m�I# � � �?u � � ¡[² � 06i � �6i 0 �3g(!'-' w i 0�i Ct �?u �mz 54C d C�7C���*2!�� 6�)-�2^9*C d !��B'�C��;��#T)[���4+.-��R��-�2g2' !20��#T)����*+<-��R�Q>;�=(: %#T�.!'-�2' +$J�* !2%!�$4+<(H>O)�$*��);: %$4(*+. +�%C �£- �=­�� �M¨M¨*�(®%�"&m¤x����¥ ¨�.�¥ � ������ #1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ ���o�m¬"���?¦(¥�®����P¤2� �m­:��¤ � �j�

�� !-�#S�($* 0��;��!'-�(H> � %$,$V>��L�H$4 %���)-�2D�vg(!'-3 w i6i!� Ct �?u��0z gPCEANC7C��(,3P'K!��,�-��-P2 gPC d C���($Q$* @(*(/C � �T�(3' %�(2D��U"+��4+<(H(&33���* d %<��4+<(: +�%��>���!�2%��-D� (-�6 !(-3"!�$4(�CZCBC2/��-�>���! � �£-��e­:� �M¨M¨*�(®%�"&m¤5���T¥ ¨ 48®%��¨[¥H¨M¨@�L¥ 46¦(¥�®����j¦(¯{#1��� �j¬;¥�¨[­ �D¨��[¬;­[®°¥ �P#1���1�/¨[­&¨@���M¨[�)L�(�6 +� 0(� � i(y � �J�(�<(*+�#$��$* 0��@��($Q>;���)-�2D� � � w�� � 2@(:��<� %$ w i6i!& C �-�=AxE ���}�HA��}Ct �?u &mz 7�CP7{���.�.+<-����4�6-DC�EG33 20�6-?U6 +$,�6 !-'20 �('�#/+B�.+9(M�($V>Y��-�2�2!+BU"+����()�)�$4�?��2M3' +�C(*�B+.-P'>�($,#S�)(:+<�6-S�4 02+!x:$*+<(H>(C��£- �=­:� �M¨M¨*�(®%�"&m¤����J¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨���� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ �#�=­:�0�(¬v�[¥°¤.®%��R¨ �/¨@���M¨�� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤��=¬;­M¤[¬;®°¥m����# � �� �e$,!P�,�* +���+� �; %�B�6+�!P#��L5 )�$*+B� u0����� C

� 5*E �RC¸ ���

Page 213: Practical Architectures for Survivable Systems and Networks (Phase

t �?u�00z gPC @ªCj7.!��,3"<?>�CG5 (&$Q!��4(* %2�20��#T)�!3(*+.-��T<L�(�4 �'>��$C +#R<[ +2�2' +21�Q>;�=(: %#T�%CG�£-��=­�� �M¨M¨*�(®%�"&m¤B���W¥ ¨�D¨��(¨@�L¥ �I� � ) 4 � �x#1��� �j¬;¥�¨[­ �D¨��[¬;­[®°¥ � �L®°¥�®r¦(¥r® �(¨k#1���1�/¨[­M¨@���M¨[�?)��(�6 %� u�i(y � �Pw�w � �W��+9(&3' +$,�V:<�!�$,�P�j@1�($Q>;����-�2D�vA" %)3(* %#R<� %$ w i 0(y C

t �?u�i0z gPC @ªC�7.!��,3"<?>�C �{ !(H�1��$,\"�A�0$* ^�Q>;�4(* %#T�%C �£- �e­:� �M¨M¨*�(®%�"&m¤ ���g¥ ¨ �R¨ �P¦(­ ¥u�O¨@�L¥7�����R¨ �/¨@�P¤�¨#1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥�� #=¨@�L¥�¨[­ � ��®°¥§¦(¥r®����j¦(¯5� �m­:��¤ � � ��� 4I¨[¥u�;�m­:� �D¨��[¬;­ ®°¥��m�j)L�(�6 +� & � u0y (*�& � �!& ���{ +� �6$Q�. %��-��%�"98��!3+��*+���-L�P�?@1�($*2M3 w i 0 � C()�!P<��§C�<?>T«F +)L�($4(,#/ !-�(D�('D«F ['> 0-��4 �;��#S)P!3(: +$A� 02+!�$*+9(H>{�; 0-�(: +$%C

t �����0z gPC @ªC�7.!��,3"<?>�C£�;�(#S)����*+<-��G(&$,!P�4(H�1��$4(,3">��Q>;�4(* %#T�%C{E� !2M3'-'+<2/�(�=$* %)���$=(/�*�;�(#S)�!�(: %$IA�20+< 0-'2! 9F�0<[��$,�)(:�($Q>��,AP7-���£-�(: +$*-L�)(*+.�6-��(�§�@? 0-��<� ��($,\�N�J�(�<+B'>��$4-'+��P��g(!��Z> w i6ixw Ct ���Pw%z gPC @ªC�7-!��Q3"<">(C �{�6-'+<-�(* %$V'> %$* !-'20 0�6(&$,��-��*+9(:+ZU�+9(H>��?�)-�2B2M3L��-'-3 %�Z:b20�6-�(,$*���x�* 02+!�$*+9(H>X)����.+<20+. +�%CxE� !2M3x:-'+.2%�(�*7C %)���$4(kAP7.�§:V�HAP9�: i?u : u �l�;��#T)�!3(: +$fA�20+< 0-'2! S9l�(<���$,�)(:��$V>���AP7.� �£-�(* %$*-��)(:+<�6-L�(���F@� 0-��<�

��($Q\j�N�J�(�<+B'>��$4-'+��x�x«F !20 +#R<[ +$ w i6i?u Ct ���?umz gPC @ªCD7-!��Q3"<">(CI5�'>��$,#S�(���Z>AU6 +$*+<l' %2£�(�B�6��$*+9(&3�# '>�($F2%�<��2M\{�Q>"-'2M3�$4�6-'+B�/�)(*+.�6-�!'-P2' %$W�g3?>;<�$*+B2'r�(!��<(-#$�x23 %�§C��£- �=­:� �M¨M¨*�(®%�"&m¤I����¥ ¨ � ®°­ ¥H¨M¨@�L¥ #1���1�/¨[­&¨@���M¨B��� �=­[®%���[® �j¯�¨M¤B��� �W®�¤[¥r­ ® %¬x¥H¨*�#1��� �j¬x¥r®%�"&(��)L�(�� %� ���(y � �Pw�� �P9Z�(�-5m-��6 +�. %�+�j�J�(�.+Z'>��$*-3+��P�"5}!P��!��4( w i6i0y CP5-�G@ªCt �����0z gPC @ªC�7-!P�,3"<?>���-�2 �}C�7-��-�23 %����C^5�2'+B�4(&$4+�<�!�(: %2��* 02+!�$* O�Q>;�4(* %#{C #1��� �j¬x¥H¨[­ � w�� � & ¡[² � � � �!& �g(!��B> w i 0�� Ct ���(y(z gPC @ªC07.!��,3"<?>X��-P2 � CoU6�6- { 0-�\) (C � ��$Q#O�(��U� %$4+<l,2%�)(:+<�6-k�('3(&3' e+<-�(: %$,��2!(*+BU� 12!�6-?U6 %$Q�6 0-320 C2%�<��2M\�Q>"-'2M3�$4�6-'+��%�)(:+<�6- �(������$*+9(&3�# !��*+<-��{� }«W@ªCREo 02M33-'+.2%�(��7{ +)[��$=(fAP7.�§:V�HAP9�: 0�i : � �a�;��#S)P!3(: +$A�20+< 0-'2! g9l�(<���$&�)(*��$Q>(��AP7-�}�£-�(* %$4-L�)(:+<�6-L�(����@? 0-��<� ��($,\���J�(�<+B'>��$4-'+��x� � %<�$Q!L�($Q> w i 06i Cg5 ���4���U0��+B���(<P�. 8�0� �-5 Ax5��;�6-�(,$&��2@(:��$-7C %)���$4( y"u0�6i Ct ���!�mz @ªC"AP�(�<�6+��*�)-�2T7�C;�e3L�0$,)� 0-�(:+< %$%CN«}>"-L�(#$+.2J23 !(: !2!(*+.�6-$�('N#O�(�<+.2!+.��!���20�;2' C+.-T� �8E{AT�4�('%(H�e�($* 0C�£- �=­:� �M¨M¨*�(®%�"&m¤����1¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨x��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤£®%��R¨ �/¨@���M¨�� � �j¯±®��,¦(¥r®����P¤�� � ¨ �.¬;¥ ¯�¨M¤M¤��=¬;­M¤[¬;®°¥m����# � �� �e$,!P�,�* +���+� �; %�B�6+�!P#��L5 )�$*+B� u0����� C

� 5*E �RCt ��� �0z �}CBAP�(�9(: +$%� �XC°ANCIAP�/>x2o�,�($*+�� �}CIA�2M3'-' !+. +$%�g�)-�2 gPC d �(�B�.-' +$%C E����e�($,2 � �4 02+!�$* �V>x�=(: +# 0-��6+<-' 0 +$*+<-���#/ @(&3'�;2'���<���(>�C��£- 4�¨@� �D¨��[¬;­ ®°¥����J¦(­Q¦��(®9&��4¤ � �m­���¤ � �j��A� +)3(: +#R<[ +$ w i6i 0 C3�(4(&)D² � �m�G�G�WCj20�(!'-�(: %$Q)L��-' 0Cµ2!��# �0�* !2%!�$4 [:H#$ !(,3'�;2'���.�(�(>�Cv3�(&#T�§Ct ���!&mz gPC �CvAP�(�9(&�0 +$G��-�2{@ C¢«RC'A�2M3�$*�" %23 %$%C*EG33 6)�$*��(* 02@(:+.��-��('o+.-P'>��$Q#O��(:+.��-/+<-520��#T)�!3(* %$J�V>;�4(: +#S�+C�e­:� �M¨M¨*�(®%�"&m¤I���8¥ ¨ ������ � ��� � i ¡[² wou & 0 � w�����0 ��A� %)3(* %#R<� %$ w i!&�� Ct ��� 00z E6C�Ax��-�2' +$R��-�2~�}C � CFEG�42M3"!�2'+.-�C%*$4��(: !2!(:+<-��{#/��<3+��. Y�0�6 0-�(&�4�(�?��+<-��4(�#S�(�.+<20+<��!��83'�(�4(&�+CA�£-

� �j­[®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤I®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��1&;¨@�L¥°¤R¦�����D¨��[¬x­ ®°¥ �0�L)L�0�6 %� y�y � ��� � w i�i 0 C

t ���6i0z E6C�Ax��-�2' +$���-P2X�}C � CoEG�*2M3"!�2'+<-DCxEo���J�0$,2���#/��<3+��. �2%$Q>;)3(*����$,�()�3?>�C;�£-��=­:� �M¨M¨*�(®%�"&m¤H����¥ ¨ +-+-/.���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ �O¦���� �=­[® �m¦"���m� �6�(\"����-�2D���J�(�.+Z'>��$*-'+��P�;@1�/> w i6i 0 Cx�������q�;��#S)P!3(: +$A���2!+. @(H>�C

¸ �!¹

Page 214: Practical Architectures for Survivable Systems and Networks (Phase

t �(y?�0z ANC�Ax��-'+B'>�($,2x:��e3' 0-��)-�2�9*C�E6C m +<[ +$,�. !+.-DC m�(��2'+<-���+<-�(,$,!�23 %$,�8��202!��!'-�(M�(<P�. k��- (&3' 4�£-�(* %$4-' !(%C�£- �e­:� �M¨M¨*�(®%�"&m¤$���4¥ ¨�+-+- � ����� �,��¤[®°¬�� ��� �D¨��[¬;­ ®°¥��{¦���� �=­[® �m¦"���m� �6�(\"���)-�2D�a�J�0�.+B'>�($*-'+��P�@1�/> w i6i!� C�������� �;�(#S)�!�(: %$mA��"20+< !(H>(Ct �(y�w%z «RCnAP��-�(: +�§�e�}C*E�$,�(!3(&#S��-'-��J��-�2 d C�98+�!DC�EG3' ?+.-�(* %��$,�)(:+<�6- �('}�£'>��$Q#O�0�J�&�0'> @(H>|��-L�(�Z>;�*+��+.-�(:�G(&3' T�*�0'%(H�J�($4 � !-��6+.-3 0 %$4+.-��{)�$4��2! %�,�+²R5�-� [�P�(#T)��. X'K$*�(# (&3' S)L��2! %#S�(\� +$f+<-�2�!��=(&$Q>(CA�£-

�e­:� �M¨M¨*�(®%�"&m¤{���J¥ ¨ ����� �,��¤[®°¬�� ���O¥ ¨ � �"&(®%��¨M¨[­ ®%�"&f��� #1��� �j¬;¥�¨[­ � � ¦m¤�¨*� � ¨*�(®��,¦(¯ ����¤[¥�¨@�4¤[�)L�(�6 +� w���u � w��my �L@�+<-'-' %�()[�(�.+��+�L@�+<-'-' +�*��(&�P��g(!'-' w i 0�0 C�������� �;��#S)P!3(: +${A���2!+. @(H>�Ct �(y"umz � C � C'A�2M33-' 0+B2' %$+C 1{-�2' +$,�4(&��-�2'+<-��R)�$4��(:�"20�(����'>��$ ��>x�%��-�(:+<-' �2+�.�"2M\T�V>"-'2M3�$*��-'+��%�)(:+<�6-DClE� !2M3'-'+ :2/�(�F7C %)���$4( 0!& : 0!��i �«F +)L�($=(&#$ 0-�({�('��;��#T)�!3(* %$mA�20+< 0-'2! (���;��$*-3 %���)1{-'+BU� %$,�4+<(H>(�N�b(,3L��2/�x� �{ +�

�n��$,\�L5}!P��!��4( w i�0!& Ct �(y?�0z � C � CvA�2M3'-' !+�2' +$%C �e� #1�����[¬;­[­&¨@�L¥#�=­��*&(­Q¦��B�X®%�"&(CDA;)�$*+<-��6 %$J D +$,���(��� �{ +� �n�($,\� w i6i!& Ct �(y�y(z � C � CoA�2M3'-' !+�2' +$%C �8)[ !-��4��!�$*2! /+<-ª�4 02+!�$*+9(H>N²I F+��4+<(*+.-��5(,3' S<3+��/�0$,$* 0CO�£- �e­:� �M¨M¨*�(®%�"&m¤5���Y¥ ¨

� �+�+� ���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ ��¦���� �=­ ® �m¦"���0�F)L�(�6 +� wou � � wou & � �6�(\"����-�2D���J�(�<+B'>��$4-'+��P�F@���>u(����� CP������� �;��#T)�!3(* %${A��"20+< !(H>(Ct �(y��mz � C � C�A"2M3'-' 0+B2' %$4��-�2�@ C��=��!�#$ 0-�(&3��(�§�o %2'+9(:��$+C ­ ¬?¤[¥}®%�X# ��[¨[­&¤ �P¦"�M¨[C �}�)(*+.�6-L�0�*7{ +�* %�($*2M3�;��!'-'2!+��§�/� �)(:+<�6-L�(��5�2%�(2' %#I> �$4 %�Q�%� uxw��Pw �;�6-P�4(:+9(&!3(*+.�6-£5-U6 (CZ� d �(�Q3'+.-P��(:�6-��l«RC �}C u(�0y�w�0 �w i6i 0 C � +.-L�0��$* +)[��$=(;�0'�(&3' �}��(:+.��-L�(�7C %�* %�($*2M3A�;��!'-'2!+��N�;��#T#/+9(*(: ! C�6-O�£-P'>�($,#S�)(:+<�6-YE�$Q!��4(V:�;��$=(&3'+<-' %�Q�%Ct �(y!�0z �IC�A�2M3'-' !+�2' [�C+.-�2�CAEG3' O$Q!3(&3��< %�Q�4)�!�$Q�,!'+9( �('e(&33 $(,$,!3(,3~�(<���!3(R� �8E{ANCA�£-��=­:� �M¨M¨*�(®%�"&m¤5���¥ ¨ 4H� � #1���1�/¨[­&¨@���M¨{��� #1���B�O¨[­:�[®r¦(¯ ��� � � ¨ � � ¨[¯ ���=­:�0�(¬,�[¥K¤.®%� �R¨ �/¨@���M¨ª� � �j¯±®��,¦(¥r®����P¤��� ¨ �.¬;¥ ¯�¨M¤M¤ �=¬;­M¤[¬;®°¥H���$# � �� �e$,!P�,�* +���+� �; %�B�6+�!�#{�P5 )�$*+B� u(���(� C � 5*E �RCt �(y�&mz �}CHA�2M33-' 0+< %$%C � � �j¯±®§¨*�X#�­ ���j¥£�*&(­Q¦ � �/���e­:�m¥£� ���m¯¢¤��I�}¯j&"�m­[®°¥ �4¤��S¦���� ���m¬x­:�M¨ #1�0�;¨1®%�N#��

�D¨�������� � �(®°¥�®����LCng���33- d +B�. +>O��-�2 A��6-P�%���m [� �n��$Q\j� w i6i � Ct �(y!00z �}C�A�2M3'-' !+. %$+C �D¨��[­&¨[¥K¤8¦���� 3�®§¨M¤�� �W®9&(®°¥§¦(¯ �D¨��[¬;­[®°¥ �R®%��¦�4I¨[¥u�;�m­:�?¨*��� �m­ ¯9�(CZg���33- d +��< +>Y�)-�2A��6-��+���m +� �n��$,\� u(���(� Ct �(y�i0z �}CªA�2M33-' 0+< %$X��-P2pgPC � %�B�* +>(C �e$Q>;)3(*����$&�0)�3'+.2O�,!�)�)���$=(R'>��$4�4 02+!�$* ^�.�(���f��-�!'-�(&$,!P�4(: +2�#O�m:2M3'+.-' +�%C �£- �=­�� �M¨M¨*�(®%�"&m¤ ����¥ ¨ �D¨��(¨@�L¥ � � � 4 �� �D¨��[¬x­ ®°¥ � ����� �,��¤[®°¬��X�})L�(�6 +� �(� � �?u C

1FAP�2� � �4�[g���-"!L�($Q> w i6i 0 Ct �!�(�0z �}C´A�2M3'-3 0+. +$��)-�2I@�!�2��6 0C"�e$Q>;)3(&��-L�(�Z>;�*+��Z�('�@�+<2%$*�(�*�('%(%���/o�6+.-�(Q:�(:�0: ��6+<-�(aE�!3-'-' %�<+.-�� *$4��(:�"20���� 2*E =¡ C��£- ��® � ¥ �I# � #1���1�/¨[­&¨@���M¨F��� #1��� �j¬x¥H¨[­ ¦�����#1���B�X¬��L®��,¦(¥r®����P¤ �D¨��[¬;­ ®°¥��m�?)L�(�6 +�

w��?u � w%y�w �,Ax��- � $,��-'20+B�*2!����J�(�<+B'>��$4-'+��P� �{�oU� %#R<� %$ w i6i�0 C�5-�G@ A;� �fAx5-�}Ct �!�xw%z @ªC¢«RC�A�2M3P$*�" %2' +$%C��;����)� %$,�)(:+<�6-$�('D#R!�(&!L�(�B�B>X�Q!��,)3+.20+<��!��=�,!�<��V>;�4(: +#S�;+.-g� 20��#T)�!3(* %$�!3(:+B�.+9(H>�CE� !2M3'-'+.2%�(�l$* +)[��$=(/� *3DC�«RCLEG3' +�*+��+�j@ªCv�MC�E6CZ�N�J�(#R<�$4+�2��6 0�@1�(�Q�&��2M3"!��4 !(4(&�%��A� %)�(: %#4<[ +$ w i &�u Ct �!��umz @ªC¢«RC�A�2M3�$4�� +2' %$+�a«RC�«RC��e���($,\�N��-�2xgPC IC�AP�(�9(&�0 +$%C-EG3' Y@�!P�<(:+<2%� \� %$4-' %��2' %�4+��6-1)�$*�m�4 !2!(%C8�£-

�e­:� �M¨M¨*�(®%�"&m¤B����¥ ¨ �® � ¥ ����� �,��¤[®°¬��~��� ���L¨[­Q¦(¥�®%�"& ����¤[¥�¨@� �=­ ®%���[® �j¯�¨M¤[���m��U6 +#R<� %$ w i!& & C5-�G@ �8)[ +$&�)(*+.-��$A">x�=(: +#S� 7{ [U"+. +� w�w � � ¡[C¸ � 3

Page 215: Practical Architectures for Survivable Systems and Networks (Phase

t �!�(�0z @ªC¢«RC6A�2M3�$4�� +2' %$���-�2$gPC IC�AP�(�<(,�0 +$%C�5 3L�0$,2P�e�($* .�0$*2M3'+9(: 02@(&!�$4 e'>��$ +B#S)P�. %#$ 0-�(*+.-��-)�$*�)(: 02@(:+<�6-$*+��Q\"�%C #1���B�X¬��L®��,¦(¥r®����P¤k���W¥ ¨��I# � � w�� � � ¡[�@��($*2M3 w i!&�u Ct �!�0y(z «RC´A� 0 +�. [>�C���0�,�Q�1��$Q2I2%$,��2M\�+.-���²a5��?�0#/ ª�(';�C+<(,�%C8#1���B�X¬"�L®��,¦(¥r®����P¤e����¥ ¨ �I# � � �?u � � ¡[² &(��� �

&(��� �vg(!3-' w i 06i Ct �!� �mz gPC � C�A;3'��2M3R��-�2kgPC�5IC -!�)�)DC"EG3' R� d ��$,#T�.)�$*���($&�(#T�N� %�($,�Z> [�x)� %$4+. 0-320 =�C+9(&3I�-23+��4(,$*+B<�!3(: +220��#T)�!3(&�)(:+<�6-DCm#1���B�X¬��L®��,¦(¥r®����P¤f���}¥ ¨C�I# � � u � � � ¡[² w�&�u � w 0�� �x@1�($42M3 w i 0?u C�7{ +)�$*+<-�(: %2G+<-«F 0-'-'+<-����u +2DC ¡ �D#1��� �j¬x¥H¨[­&¤ �Z���;¨[­��}¥r¥§¦"���mCt �!���0z ANC �XC�Ax3�$4+BU0�(�=(M�/U0�4��-�2 � C ���-P�0+. +$*+�CDEG3' }23 %�*+B�6-��0'l�I$4 %�.+��(<��< G$* %#$��(* )�$4��2! %2�!P$* �2%�(���L#$ 02M3;:��-'+��Q#�C ������ ­Q¦��P¤%¦"�[¥�®����P¤f��� #1��� �j¬x¥H¨[­&¤[�j��: �Pw � & ¡ ² �6i�u � � 0!& �'g(!��Z> w i�0?u Ct �!� &mz �XC�A�+�<� %$=(/� �Cv54C ���$Q$&�(�+�a��-�2£7WC�98+<-�2' %�B�§C 5�-£��-L�0�B>;�*+B�m�('D(,3' R�£-�(: +� 0�� � 0 � �* 02+!�$*+9(H>��($42M3'+Z:(: 02@(&!�$4 R��-P2�+B#S)��< %#$ 0-�(M��(:+.��-��%C ������ ­Q¦��P¤%¦"�[¥�®����P¤k��������� ¥u��¦(­&¨ � �"&(®%��¨M¨[­[®%�"&(��Ax��: u�u � y ¡[�@1�/> w i6i � Ct �!��00z «RCoA�+�2�3"!D�l5ICF�e3;!3-������)-�2ªE6C �C �e�B!�#$ %$%CY���x)� %$*+< 0-'2! T�C+9(&3£'>��$,#S�(��#/ @(&3'�;2���+.-£)�$4��(:�"20���2' +U� %�.�()�#/ !-�(/C"�I# � � � # � � � #1��� �j¬x¥H¨[­{#1���B�X¬��L®��,¦(¥r®���� �.¨���®§¨@�*� uxw � u ¡[² 0Pw � w��xw ��5})�$4+��w i6iPw Ct �!��i0z �}C�A"+�#$�6-��%CmAx3P$*+.-P\?:§�.$&�()P)'+.-��/��!�$-$*+B��3�(&�%C/#1���B�X¬"�L®��,¦(¥�®����P¤B���I¥ ¨ �I# � � y?� � 0 ¡ �j5 !���!��=(u(����� Ct � ���0z �.C IC;Ax)L�m����$Q2DC�EG3' 1�£-�(: +$*-' @( d ��$,#{² 2+$*+B�*+��O��-�2q�0'%(: +$,#S�)(&3DC #1���B�X¬"�L®��,¦(¥�®����P¤ ����¥ ¨�I# � � �?u � � ¡ ² �!& 0 � � 0!& �'g(!'-3 w i 06i Ct � �Pw%z «RCªAx)'+<-' %�B�.+B�%C�A"�('%(H�J�0$* A$* +�.+��(<'+��<+<(H>j²Y@��;2' +$*- 2M3L�(�B�. 0-P�6 %�+C��£-2�=­:� �M¨M¨*�(®%�"&m¤G��� � � � � 3 -+-�� ¨@�L¥ �� ¬;­�� �L¨,¦���#1���1�/¨[­&¨@���M¨C��� �N¦ �/¨[¥ �W¦���� �-¨[¯±®r¦%¯±®°¥ �m�()L�(�� %� � 06i � ��i�u ��@{!'-'+.2M3;: �W�($*2M3'+<-����

�� +$,#S��-?>��,A" %)3(* %#R<� %$ w i6i6i C�Ax!�#T#S�($*+B�0 %2�+.-/(,3' 67C+��Q\;� � �($,!�#{�;U�����!P#/ u(� �3-"!�#4<[ +$ �(y � y�m��U6 +#R<[ +$ w i6i 0 ��-�2^5-�G@ Ax� �fA � � E ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­[®%�"& 4f�m¥H¨M¤ � � � u � w�& � w 0 �L@1�0$*2M3u(����� C

t � �?umz AP7-�§:��HAP9*C �D ��� � �L¨��[® �e�,¦(¥r®����£¦���� � ¨[­ ® �e�,¦(¥�®���� ���o¤[¥H¨@� � ¨[­&¤[®���� ��� +�5�e­&¨[¯±®%�X®%�j¦(­ � �R¨�� ��L®°¥�®��������-¥ ¨ � � � � �L¨��[® �e�,¦(¥r®���� 3D¦��"&(¬�¦ &;¨[CF�;�(#S)�!�(: %$;A�2!+. 0-320 69l�(<���$&��(:��$V>���AP7.�*�£-�(* %$�:-L�)(:+<�6-L�(����@? 0-��<� ��($,\�j�J�(�<+B'>��$4-'+��P� � A� %)�(: %#4<[ +$ w i�0 0 Ct � ���0z @ªC Ax$4+BU0�(����-�2�5IC8�J�(#$+��B�. +$*+§�m %2'+9(:��$Q�%C ���m­±�T¦(¯ � ¨[¥ �0�m¤ª®%� #1��� �j¬;¥�¨[­ � �}®u�;¨*���R¨M¤[®9&��LCAx)�$*+<-��6 +$V:] D +$,���(��� �1 %$,�<+.-D�P98 02!(,!�$* �m�)(: %�C+<-1�;�(#S)�!�(: %${A"20+. !-'20 0�L D���§C w�w�� � � w i6i � Ct � �(y(z gPC �XC A�(: 0+<-' %$+�*�}C �m +!�#O�)-D�*��-�2 gPC��MC�A�2M3'+B���. +$%C � %$Q<[ +$*���+²Y5�-��(!�(&3' !-�(*+.2%�)(:+<�6-��4 %$QU"+<20 S'>�($��)[ !-G-' !(H�1��$,\A�V>;�4(: +#S�+C=�£- �=­:� �M¨M¨*�(®%�"&m¤k���W¥ ¨ � � � 4 �� �A®%�L¥�¨[­$#1���1�/¨[­&¨@���M¨[�P)L�0�6 %� w iPw �u(�?u � � +<�$,!L�0$Q> w i�0 0 Ct � �!�mz «RC¢�GC�A"(* +U6 !-��*��-DCe ��(�<+�2L�)(*+.�6-g��-�2^U6 %$4+<l,2%�)(:+<�6-{#/ @(&3'�;2'���<���6+. +�e'>��$G���($,�6 6�42/�(�< W�*+�#4!����)(*+.�6-P�%²EG3' %$4 O�($4 7-'���4+��ZU6 %$63��(#S#$ %$Q�%�Z 0+9(&3' +$%C ������ #1��� �j¬;¥]¦(¥r®����j¦(¯ ���[®§¨@���M¨T¦���� � �"&(®%��¨M¨[­ ®%�"&(�

w i6i 0 Ct � � �0z �}C'A"(*������C8A"(&�(��\�+<-�� (,3' d +B�B> ��2M\� +$%Cm#1���B�X¬��L®��,¦(¥r®����P¤ ���}¥ ¨H�I# � � �Pw � � ¡[² y!0(y � y�i!& �;@���>w i 0 0 C

¸ �0º

Page 216: Practical Architectures for Survivable Systems and Networks (Phase

t � �!&mz �}C�A"(*������C � ¨�#�¬,����� � � ¤ � & &+� ­Q¦"���m®%�"&�¦ � ��� � ­:�m¬6& ¥ ¨ � ¦ �m¨���� #1��� �j¬;¥�¨[­ � ¤ �j®����j¦ &;¨[C«F��!�<��< %2L�/>�� �m +� �n��$,\� w i 0�i Ct � � 00z «RC d C°gPC6A�(&$*+<-��6 +$V:V�J�0�BU6 +$4(%C � ¨�� ¦��L®��,¦(¯ � ¨[­ ® �e�,¦(¥r®����G����#1��� �j®°¯�¨[­F#1�m­ ­&¨��[¥u��¨M¤M¤[C *3L« (,3' %�4+��+�«F %)L�($=(&#$ 0-�(C�('��;��#T)�!3(: +$mA�20+< 0-'2! (� 1m-'+ZU6 +$,�*+9(H>��(' �n��$,\� w i�i 0 Ct � �6i0z �YC8Ax!����<+BU0��-D��gPC¢�}C � -'+���3�(%� �RCa«8!��a��-�2 ANC � 0+B�4(%CI�£-P'>�($,#S�)(:+<�6-1�Q!�$QU"+BU0�(<3+��.+9(H>?20�6-�(&$4�����V>x��:(: %#T�%C��£- �=­:� �M¨M¨*�(®%�"&m¤G���O¥ ¨ +-+-+- �L¥H¨[­±�j¦(¥�®����j¦(¯{#1���1�/¨[­&¨@���M¨G��� ����� ¥u��¦(­&¨ � �"&(®%��¨M¨[­ ®%�"&

" # � � &m� w i6i�i Ct �!&(�0z «RC��MCoAx!�(&3' +$,���)-�2DCO5 #$�x2' +�ª�('e+<-P'>��$Q#O�)(*+.�6-��,���WCO�£-��=­:� �M¨M¨*�(®%�"&m¤5���Y¥ ¨ 48®%�L¥ 4W¦(¥r®����j¦(¯#1��� �j¬x¥H¨[­ �D¨��[¬x­ ®°¥ � #1���1�/¨[­&¨@���M¨[�P)��(�6 %� w�&�� � w�0�� �,A� +)3(: +#R<[ +$ w i 0 � Ct �!&xw%z 7�C�EG33��#O�0�*��-�2T7WC � 0+. +$4(&�(��CL5}2P2�$* +�,�*+<-��W�,!�$VU"+BU0�(<'+B�.+<(H> +<-I(&3' C20�(#S)����&�0<��. =$* %)P����2! /�(<��< G�* :2%!�$4+<(H>T�* +$QU"+.2! %�;+<-P'K$&�0�4(&$Q!'2!(,$* 0Ca�£- �C��¤[®°¥�®���� �J¦ �L¨[­M¤ � �m­ ¥ ¨ +-+-/. �1� �m­±�T¦(¥�®���� �¬;­���® �m¦%®°¯±®°¥��

� �m­:��¤ � � � � � � -/.��P)L�(�6 +� w��)i � w��?u � �8$,����-�2'��� � �.�($*+�2��P� u 0 � ��� �F2!(*��<[ +$ w i6i 0 C��������GCt �!&�umz �YC;EG3'��#T)��4�6-DCF7{ [�, 02@(:+<�6-��e�6-$(&$Q!��4(*+.-��k(,$,!��=(/C{#1���B�X¬"�L®��,¦(¥�®����P¤���� ¥ ¨C�I# � � u & � 0 ¡[² &��Pw �

&���� ��5 !���!��=( w i 0(y Ct �!&(�0z gPC¢�GC�EH+B2��Q�1 %�B���-�2$gPC¢@ªC����(4(: +$%C5 2P>"-L�(#$+.2%�(���Z> (H>x)� %2S��2!20 %�Q�12!�6-�(&$4����#$�x2' +�§C��£- � �j­ ®%�"&;¨[­ �

� ¨[­[¯Z¦ &�� �8¨[­ ¯±®%�3��3l¨��[¥r¬x­&¨ 4 �m¥�¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨ � � .)� �1� �m­±�T¦(¥�®���� �D¨��[¬x­ ®°¥ ��¦�����e­ ® �m¦"��� � � ®°­4�G�}¬"¤[¥r­Q¦(¯Z¦m¤[®r¦�� #1���1�/¨[­&¨@���M¨��H�I# � � � -/.)� �.­ ®�¤ M¦���¨��H�}¬"¤[¥r­Q¦(¯±®r¦(�*)L�(�6 +� ��� 0 ��Pw i �vg(!3-' w i6i 0 C

t �!&0y(z gPC�E6CEF$*���=(&�. 0C*EH+�#$+.-��Y��(*(M�)2M\;� �(�?�)+.-��=(H(&$,!P�4(: +2�)��)(&3DC��£-��e­:� �M¨M¨*�(®%�"&m¤f���W¥ ¨ +-+-/. ����� �,� �¤[®°¬�� ��� �D¨��[¬x­ ®°¥ �W¦����5�=­ ® �m¦"���0� �6�(\"����-�2����J�(�<+B'>��$4-'+��x�o@1�/> w i6i 0 C/������� �;��#T)�!3(* %$�A��"20+< !(H>�Ct �!& �mz 1 �}:V@���«RC �L¥�¨[­ ®%� �R¨ �/¨@���M¨ �¥]¦����?¦(­4� �+� � � � � � ¨��=­:� �[¬x­&¨@�O¨@�L¥m��� �N¦ �/¨[¥ � � #�­ ®°¥r®��,¦(¯ ����� ¥ ���¦(­M¨4®%� �4¨ �/¨@���M¨ � � ¬;® ���O¨@�L¥�C'1�C �XCD@�+.-'+B�4(,$Q>��('�«F +'> !-'20 0� � 5})�$4+�� w i6iPw CW«F +'hA"(&��- ��� : � � �

��($=( w ���H�,�Q!' w ²=7C %�"!'+B$* +#/ !-�(,�0����($4( u ���H�Q�,!' w ² �6!'+�2L�)-'20 0Ct �!&��0z 1 �}:V@���«RC �L¥�¨[­ ®%� �4¨ �/¨@���M¨ �¥§¦����?¦(­4� �+� � � � � 6¦ ��¦(­4�k���j¦(¯ ��¤[®�¤�¦���� �N¦ �/¨[¥��?#�¯Z¦m¤M¤[® �e�,¦(¥r®�������e¥ ¨ #1��� �j¬;¥H¨[­G¦���� �e­:�*&(­Q¦��B�T¦%¯�¨ � ¯�¨��[¥�­:���L®�� ���o¤[¥H¨@� � ¯�¨@�O¨@�L¥°¤{�����4¨ �/¨@���M¨ � � ¬;® ���O¨@�L¥�C

1IC �YCj@?+.-'+B�4(&$V>5�('�«F +'> !-'20 0� � 5 )�$*+B� w i6ixw C*«F +'hA�(M��- ��� : ��� Ct �!& &mz 1FA":\A� 0-L��(: (C �D¨��[¬;­ ®°¥��S®%� # � [¨[­&¤ �P¦"�M¨[C21�CEANC�A" 0-L�)(* o %$Q#O��-3 0-�(�Ax!�<�20��#T#/+9(*(* 0 �6-^�£-?U6 +�4(:+ :�?�)(:+<�6-��H�('o(&33 kA" 0-L�)(* I�;��#S#$+<(4(: ! F�6- ����U6 +$*-�#$ 0-�(&�(�a5 ����+�$Q�%� { /�($4+.-��(�%�vANC -$,��C w/�(y : &0�Pw �g(!'-' w i6i � C*�=A � � � : w � : �!�0�6iPw�� : & Ct �!&�00z �IC IC( ���+B2P>?�xC�5 2/�(�4 J'>��$�(H�1�0:]�. +U� %��$4 02!�oU� %$V>Y�*2M3' +#/ +�%C ������ ­Q¦��P¤%¦"�[¥r®����P¤���� #1��� �j¬;¥H¨[­M¤[�

y�& � � ¡[² �!��� � ��� � �3g(!'-' w i6i 0 Ct �!&�i0z @ªC= �+�2��6 +$g��-P2agPCJ«F /�)-DC @1��+<-�(&��+.-3+.-���� �8E{A":H<L�0�* %2 �V>x�=(: +#S�+C �£- �=­:� �M¨M¨*�(®%�"&m¤����1¥ ¨

4C� � #1���1�/¨[­M¨@���M¨�����#1���B�O¨[­��[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤�®%�2�R¨ �/¨@���M¨�� � �j¯±®��,¦(¥r®����P¤��� ¨ �.¬;¥ ¯�¨M¤M¤ �=¬;­M¤[¬;®°¥H���$# � �� �e$,!P�,�* +���+� �; %�B�6+�!�#{�P5 )�$*+B� u(���(� C � 5*E �RCt � 0��0z �YC" F+B�6-L�PC��e$Q>;)3(*����$,�()�3'+<2�(&$,��20 +�e'>��$e#$��<'+B�. �(�6 !-�(,�%C��£-�� �j­ ®%�"&;¨[­ � � ¨[­ ¯Z¦ &�� �8¨[­ ¯±®%�3� 3l¨��[¥r¬x­&¨4f�m¥H¨M¤�®%� #1��� �j¬x¥H¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥K¤I¦���� �D¨��[¬;­ ®°¥��m�L)L�(�� %� w��!& � w��(� � w i6i 0 C

¸ � �

Page 217: Practical Architectures for Survivable Systems and Networks (Phase

t � 0Pw%z �YCj F+���-L�P�� +2DC � ��%®°¯�¨��1&;¨@�L¥°¤T¦���� �D¨��[¬x­ ®°¥ �0CfAx)�$4+.-��� %$V:§ D %$Q���(��� �; %$Q�.+<-D�D98 02@(&!�$4 �m��(* %� +<-�;��#S)P!3(: +$�A"20+. !-'20 w/yPw i � w i�i 0 Ct � 0?umz gPC @ªCl D�?�(�I��-�2 �YC�@�2 �W$,���WC ����� ¥u��¦(­&¨��a¦(¬;¯±¥ � � ¨��[¥�®���� � ��� �[¬;¯Z¦(¥r®%�"& �=­:�*&(­Q¦��4¤k�1&?¦(®%�P¤[¥

� ­ ­:�m­&¤[Cng���3'- d +��< +>A�)-�2 A"�6-��%���{ +� �n��$,\� w i6i�0 Ct � 0��0z «RCj D���B)L��-'�g��-�2 �XC�Ax#$+<(,3DC69l��-��(!L�(�6 f+��,�Q!' %� +<-�#$��<'+��< I)P$*����$,�(# �* !2%!�$4+<(H>�CW�£- � �j­ ®%�"&;¨[­ �

� ¨[­[¯Z¦ &����8¨[­ ¯±®%�3� 3l¨��[¥�¬;­&¨ 4f�m¥H¨M¤�®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨�� +-�� � ��%®°¯�¨��n&;¨@�L¥°¤I¦���� �D¨��[¬;­[®°¥ �m�)L�(�6 +� u�� � y?� � w i6i 0 Ct � 0(y(z gPC0U6��- �{ %!�#S��-'-�C *$*��<L�0<'+��<+��4(*+.2��.�(�6+.2+����-�2I(,3' J�V>�-�(,3' %�4+��D�('$* +�.+��(<��. n��$Q�?��-'+B�,#T�F'K$4��#�!3-�$* :�.+��0<��. n20��#T)��6-' 0-�(,�%CL�£-/�}¬x¥£���T¦(¥§¦ �¥�¬3�(®§¨M¤[��)L�0�6 %� y?� � i 0 ���$4+.-'2! !(*�6-�1m-'+ZU6 %$Q�*+9(H>���*$*+<-'20 @(:�6-D�

�m +� g� %$Q�* +>(� w i!��� Ct � 0!�mz «RCEANC d �(������2M3DC"� 4�¨@� � � �j­:�%¦"� ¥\� � ��%®°¯�¨F#1�0�;¨ �D¨��[¬;­[®°¥ �mC *3L«p(&3' +�*+��+�?�;��#T)�!3(* %$�A�20+< 0-'2! «F %)L�($=(&#$ 0-�(/� *$*+<-'20 @(:�6- 1{-'+BU� %$,�4+<(H>(�,g���-"!L�($V> w i6i6i Ca3�(*(,)D² � �m�G�G�WCj2%�%Cv$*+<20 0Cµ +2�!����/2x�J�(�B����2M3 �xCt � 0 �0z «RCEANC d �(�B����2M3Y��-P2O�GC d C � +�<(* 0-DC 1m-�23 %$,�=(M��-P2'+.-��kg��/U0���=(M��2M\I+<-��,)� 02@(:+<�6-DCj�£- �=­:� �M¨M¨*�(®%�"&m¤F���¥ ¨�+-+-/. ���)� �,��¤[®°¬"� ��� �D¨��[¬x­ ®°¥ ��¦���� �e­ ® �m¦"���m� �6�(\"����-�2��F�J�(�.+Z'>��$*-'+��P��@1�/> w i6i 0 CD��������;��#S)P!3(: +$�A"��2!+. !(H>(Ct � 0!&mz d C �C d �($* 0C A� !2%!�$4+<(H>�20�6-�(,$*���B�-'>��$m20��#T)�!3(* %$ �Q>;�4(* %#T�%C}Eo 02M33-'+.2%�(��$4 %)���$4(%�D7.5 �}«�$* %)���$=('>��$e(&3' �«F ['> 0-��4 IA�2!+. !-'20 �;�?�0$,2D� w i!&(� C2�{�o� �6-x:]�.+.-3 6�)(.3�(*(,)D²����)2%$V>x)�(:��#$ (Cj��$,�!�0�*2!2%�%Cv3�(&#{Ct � 0 00z d C �C d �($4 (C�5 $* @(&$4���,)� 02@(:+BU� ��0'm(,3' �2+$*+9(: %$4+���#$��U6 %#$ 0-�(%C|�£-2�=­:� �M¨M¨*�(®%�"&m¤����A¥ ¨ � ®9& �¥�¨M¨@�L¥ 46¦(¥�®����j¦(¯ �1� �m­±�T¦(¥�®���� ����¤[¥�¨@�4¤ �D¨��[¬x­ ®°¥ �x#1���1�/¨[­M¨@���M¨[�N)L�(�6 +� ��0?u � ��0 0 � �J�(�<(*+�#$��$* 0�@1�($Q>;����-�2D� w/� : w�� �F2!(*��<� %$ w i6i � C � �=A;E ���8�HA��}Ct � 06i0z gPC �C d 0-P�,�. [>$ !(e�(�§Ca«F +�*+B�6-S�=(&!�2x>/�0'a�*�('%(H�e�($4 [:£+B#S)P�. %#$ 0-�(* %2Y'r�(!��<(V:b(*���. +$&��-'2! ���Ax� � E-¡D2!��#Y:)�!3(: +$%C �-5 Ax5 20�6-�(,$&��2@(:��$�$* %)���$=( ���Pw(w �?�;��#T)�!3(* %$ A�20+< 0-'2! J9l�(<���$&�)(*��$Q>(��AP7.�a�£-�(: +$*-L�)(*+.�6-��(�§�@� 0-��<����($Q\j�N�J�(�<+B'>��$4-'+��x�3g(!3-' w i 0?u Ct �6i��0z �MC d 3'+9(: 0C d $&�0)�)'+.-P�/(&33 X� �8E{A�2'+B�. %#T#S�PCe�£- �=­:� �M¨M¨*�(®%�"&m¤7����¥ ¨ 4C� � #1���1�/¨[­&¨@���M¨B���#1���B�O¨[­��[®r¦(¯ ��� � � ¨ � � ¨[¯ � �=­:�0�(¬v�[¥°¤I®%� �R¨ �/¨@���M¨{� � �j¯±®��,¦(¥�®����P¤�� � ¨ �G¬x¥ ¯�¨M¤M¤ �=¬x­&¤[¬;®°¥{���# � �� �e$,!P�,�* +���+� �; %�B�6+�!�#{�P5 )�$*+B� u(���(� C � 5*E �RCt �6iPw%z �MCEANC d +.-�\"�. +$%C o���*+9(:+<�6-X)L�()� %$+CL�£- �C��¤[®°¥r®������J¦ �L¨[­&¤ � �m­G¥ ¨ +-+-/. �1� �m­±�T¦(¥r®���� �¬;­���® �m¦%®°¯±®°¥��

� �m­:��¤ � � � � � � -/.��P)L�(�6 +� w�0�i � w iPw � �8$,����-�2'��� � �.�($*+�2��P� u 0 � ��� �F2!(*��<[ +$ w i6i 0 C��������GCt �6i?umz d C¢«RC�n��!3-��T��-�2 gPCj@�2 -!���3DCe�;�x23+.-��X'>��$.�Y<[ +�.+< +U0�(<��< 8�,)� 02!+<l,2%�)(:+<�6-�(:�7+�#T)��. +#/ !-�(M�)(*+.�6-#O�()P)'+.-��PC��£-��=­:� �M¨M¨*�(®%�"&m¤I���W¥ ¨ +-/. ����� �,��¤[®°¬�� ��� �D¨��[¬;­ ®°¥��g¦���� �=­ ® �m¦"���0�L)L�0�6 %� w/y?� �w/y!0 � �6�(\"����-�2D��J�0�.+B'>�($*-'+��P�x5 )�$*+B� w i 0 & CP������� �;��#T)�!3(: +$mA���2!+. @(H>�Ct �6i��0z gPC � �(<L�0$,�,\?>(C � ��+B��!�$4 $4 020��U� %$Q>S'>��$e23+��4(,$*+B<�!3(: +2g)�$4��2! %�,�4 %�C+.-S�*+<-����. �Q>;�4(* %# +�#S�(�6 {2%��!P�4(: +$,�+C�£- � �j­ ®%�"&;¨[­ � � ¨[­[¯Z¦ &�� �8¨[­ ¯±®%�3��3l¨��[¥�¬;­&¨4f�m¥H¨M¤ ®%� #1��� �j¬;¥�¨[­ ���[®§¨@���M¨ � .+.)���J¦(­Q¦(¯°¯�¨[¯W¦����

�W®�¤[¥�­ ® %¬;¥�¨*���=­:� �M¨M¤M¤[®%�"&(�P)��(�6 %� ���0y � ��0�� � �; +$,�.+<-D� � %$Q#O��-?>(��5})�$4+�� w i6i 0 Ct �6i(y(z 54C � �(\�+.-�(&33+.-'������-P2��GC°ANC�98 ! (CgEG3' /20��#T)����&�(<3+��.+9(H> �0'e-'�6-;:£+.-�(* %$Q'> +$* !-'20 0Cg�£-��=­:� �M¨M¨*�(®%�"&m¤���4¥ ¨ .�¥ ������ #1��� �j¬;¥�¨[­ �D¨��[¬x­ ®°¥ ���o�m¬����?¦(¥r®����P¤ � �m­:��¤ � �j� � 0-�#S�($* 0�D�;�(!'-�(H> � %$Q$Q>(��H$* %����-�2D�,g(!'-' w i6i!� C

¸ � �

Page 218: Practical Architectures for Survivable Systems and Networks (Phase

t �6i!�mz 54C � �(\�+.-�(&3'+<-'���F��-�2R�.C°ANC098 0 (C��;��#T)[���4+.-�� �* !2%!�$4 J�Q>;�4(* %#T��(&3��)(�3���U� e %#$ %$Q�6 0-�(�)�$*��)� %$=(:+< %�%C�£-��=­�� �M¨M¨*�(®%�"&m¤{���=¥ ¨ +(¥ ������ #1��� �j¬x¥H¨[­ �D¨��[¬;­ ®°¥�� �o�m¬"���?¦(¥�®����P¤ � �m­:��¤ � �j�m)L�(�6 +� w�w�& �wou�u �L7C�"2M\;)���$=(/�j@1�(�Q�&��2M3"!��4 !(4(&�%��g(!'-' w i6i�0 C

���

Page 219: Practical Architectures for Survivable Systems and Networks (Phase

� � � � �

5}<P�4(&$,��2!(*+.�6-�� & � w��Pw3'��$4+��0��-�(&�(�§� w��?uU6 +$4(:+<2/�(��� w��?u5�2!20��!3-�(&�(<'+B�.+<(H>+.-^2' +�*+���-D� w����5-�G@ �4(&��-�2L�($Q2��%� i��5}2P#/+<-'+��=(&$&��(:+.��-20�6-�(,$*���B���(<'+B�.+9(H>�� w����5}�9(: +$*-L�)(*+BU� 6$*��!3(*+.-��P� w��5�-��(�B>;�*+B�$* %�(�Z:�(:+�#$ (� i?u�4(&�)(:+<2(� iPw5�-P2' %$Q�*�6-D�[g��(#$ %�+� w��!�5}$42M3'+<(* 02@(&!�$4 �(<��=(&$&�)2!(4��« � Ax56¡ � w�����6 0-3 %$*+<2S��« � Ax56¡ � w�����.����+.2/�0�*��« � Ax58¡[� w �����)� %$&��(:+.��-L�(�*�hg(E�58¡[� w�� 0)[�($4(M�0<��. 2!��#S)P!3(:+<-���� w�u(��* +�. 02@(:+ZU6 (&$Q!��4(H�1��$4(,3'+.-3 %�,�+� w/� 0 � w���i�4(,$,!'2@(&!�$,�(�§� w/����Q>;�4(* %#T�R�hg(E�58¡[� w�� 0(: !2M3'-'+.2%�(����g(EF56¡ � w�� &(&3'+<-x:£2+�.+< 0-�(/� w��6i�C+�$4 %�. +�,�+� wou(�5}�Q�,!�$,��-'2! (� �5}!P2'+<(&�(<'+��<+<(H>(� � �5}!�(&3' !-�(*+.2%�)(:+<�6-D� �0y�/U6�6+B2'+.-��BlP�� +2�)L�0�,�Q�1��$Q2��%� � 0��/�.�%� � �+.-^E-�HAP���}� i!&)[ +$QU0�(�4+BU6 0� w�����* +$QU6 +$,�+� w�w/��*+<-����. 6�4+��6-;:£�6-D� � 0�,!�<P�Q>;�4(* %#T�%� w�w��

�Q>;�4(* %#$+.20� �(y5 U0��+B���(<3+��.+9(H>�� y � �my#R!��9(:+��< +U� %�*��@19a56¡ � w���J��2M\"!�)(&$Q!��4(H�1��$4(,3?>�� �(y�e5�� 98����+.2(� 0���J�($4-' %�+�5�-�(&3'��-">(� w/y!�20��!P$,�* 0� w��xw�,!�$VU"+BU0�(<'+B�.+<(H>S�4(,!�2P>(� ��J�($=(:�6-��7�C°ANC$* +)�$* +�* 0-�(&�)(:+<�6- �('��4(,$,!'2@(&!�$4 (� &�0�e����2M\ }�/�.\+.-�(: +$Q'> +$* 0-320 (� u0y�e����2M\�:H<����A�*�('%(H�e�($* 0� 0Pw�e�B!�#/ !-��4(*+. +�§�P5 �. ���)-�2' %$-«RCZ� y�&�;�"��(&�<�?�(2'+<-��+.-�(: +��$*+9(H>�� w(w/y�e$4����\"�+� � $4 %2' +$*+<2M\,�C@{>�(&3'+<2/�(�F@���-�@?�6-�(&3D� w/y��(&3�$4���S�6-' ��/�e��>(� w/y?��e!P�[ %$C��U6 +$Q�,��� ��-��(�B>;�0 +$%� 00y�=>;�/�)-�(*+.-' �(��$4 0 %#$ 0-�(%� & &�(!3(,3' 0-�(:+<2/�)(*+.�6-^)�$4��(:�"20�(���%� w�w�(!3(,3' 0-�(:+<2/�)(*+.�6-^�4 %$QU� %$Q�%� w�w��2%�<��2M\"�%� w�u2'+���+<(M�0���*+B�6-L�)(,!�$* 0� w�w'r�(!��9(&�%� w�� � 0(y\� [>G %�*2+$*���W� w�w)�$*�)(:�"20���B�%� w���J�()L�0<'+��<+<(H>g@1�)(&!P$*+<(H>^@��x23 %�§� iPw�J�($4-' %�6+< [:�@� %�B�.�6-A�£-��=(:+9(&!3(* W'>�(${Ax!�$QU"+ZU(�0<��. A;>;�4(: +#S�4�§�G@{�=A'A�¡[� w�����J�(!��4 %�m�('�$4+��Q\;�+� u�i�J��7�E6� w�� �

�´¸

Page 220: Practical Architectures for Survivable Systems and Networks (Phase

�(2PU"+��4��$*+< %�+� w�� ��;���($,2'+<-L�)(:+<�6-^�; !-�(* %$+� �(y�; %$=(:+9l,2/�)(* �(!3(,3'��$*+9(:+< %�%� &(�)�!�<��<+.2 :H\� [>�� &(��; %$=(:+9l,2/�)(*+.�6-�('�2' +U� %�.�()�#/ !-�( )� %$Q�*�6-3-' %��� iPw�('�2' +U� %�.�()�#/ !-�( )P$*�"20 %�Q�* +�%� iPw�e3L��+<-'+.-P�Y9F�/>� %$* +21�£-�(: +��$*+9(H>{�e3' !2M\;�+� w�w%y�e3' !�6-���� ��(,'K$4+. +2 ->;)� %$,���)(: �N� w/y!��e�H5 �R� i!��e�.�"2M\"�2' %)� 0-P2L�(<��< (� wou�e�.��U� %$,2��(�. 0� i ��G@��=A'Aj� w � ��;��#T#/+9(&#$ 0-�(-'�6-"<��<��2M\�+.-P��� w��(H�;�m:H)�3L�0�* (� w���;��#T#/��-{�e$*+<(* %$4+��P� i!&�;��#T#/��-A�£-�(,$,!��4+.�6-�«F !(* 02@(:+.��-� $,�(#$ +�1��$,\��§�e��« � ¡ � w�w�&�;��#T#R!'-'+9(H> �8)[ !- A���!P$*20 �$4����$,�(# ���/2! �§� ��A �W¡A;�C+<(*2M3' %2 d �($,\"�4(&�)(:+<�6-D� w���i�;��#T)[�(�&�(<'+B�.+9(H>�� w��?u�;��#T)[�(�*+<(*+.�6-�6 0-3 %$&�0�.+��! %2D� i#/�;2�!����($%� & � & &�;��#T)�$*�(#/+B�*+�<3+��.+9(H>�� w��'K$*��# <[ +�.���W� w��'K$*��# ��!3(,�*+�23 (� w��'K$*��# �C+<(,3'+.-D� w���;��#T)�!3(* %$l�*#/ +$,�6 !-'2+>67{ +�,)��6-��* �Eo /�(# �§�J��7�E-¡ ��(y�(2PU"+��4��$*+< %�+� w�� ��;��#T)�!3(* %$,�-�)(-7C+��Q\� 0 � i!��;�6-3l�2' 0-�(:+��(�.+9(H>�� �my�;�6-3l���!�$&��(:+.��-#O�)-L�(�6 +#/ !-�(C�0'�� &0y�;�6-�(&$4���a�Q>;�=(: %#T�%� w�w(w�;��)?>;�. ['%(20��!P$,�* -'��(* %�+� w��(� � w���u'>��$G�*�0'%(H�J�($4 (� 0��

->;)� %$,���)(: �N� w/y!��;��U6 +$4(m2M3L��-'-' +����/U6�6+B2L��-'2! (� � � � w � � %#$ %$Q�6 0-�(/�P��+<+§� w��+.-�(&$Q!��4(* %2�)L�)(&3P�%� �0y�4(*��$&�(�� (� y?�(:+B#/+<-���� y?��;���J�)-D�N�e$*+��Q)'+.-�� 0(y�e$*+9(: +$*+���;��#T#/�6-��e$4+<(: +$*+��P� i!&�eE-� ��=�}� i!& +U0�(�B!L�)(:+<�6-D� i!&�HE{AP���}� i &E-�HAP���}� i &�e$*+9(:+<2/�(�0�£-P'K$&�(�=(&$Q!'2!(,!�$* �5}�Q�,!�$,��-'2! ���$20 ���e�H5 ��¡ �w�� ��e$Q>;)3(*����$,�()�3?>�()�)��<+.2%�)(:+<�6-��%� w�wou2%$,��2M\�+.-��S«6�nAN� �!�'r��+�$e)�!�<��<+.2[:]\� [>�� w�w3L�($Q2P�J�0$* +�#T)��. +#/ !-�(* %2D� w�wou+.-^�*�0'%(H�J�($4 (� � �+.-^�Q>;�=(: %#T� ��-�2?-' !(H�1��$,\"�+� 0\� [>^#O��-��(�6 %#$ 0-�(%� w�wou)�$*�)(:�"20���B�%� �!�)�!�<��<+.2 :H\� [>�� w�w�u«F+ �/ : { %���B#O�)-D� w(wou7mAx54� y(y � w�wou�* !2%$* @(Q:]\� +>(� w(wou�,3L�0$* %2;:H\� [>�� w�wou�*�('%(H�e�($4 f+B#S)��< %#$ 0-�(: +2D� w(wou(&3�$4 %�Q3'����2{�*2M33 %#$ %�%� w�w�eE-� ����}� i!&�eE{A'A^�* 02+!�$*+9(H>G [�x)����,!�$4 (� w�&

«6«�A'Ax5I� w�w��«F /�)-D�«8$* [�W� w/y!�3L�(�Q3'+.-��Y�1 /�(\�-' +�,�* +�%� � 0g��/U(�/A� !2%!�$4+<(H>{@1�)-L�(�6 +$4�hg�A�@�¡ � wou�u*3L« (,3' %�4+��%� w�u(�«F 02!��#T)[���4+<(*+.�6-#/�;2�!����($%� & � & &«F 0 +)��e$,��2M\� �!�«F +'> !-��* +�

��

Page 221: Practical Architectures for Survivable Systems and Networks (Phase

�(�?��+<-��4(C2!��#T)�$*��#$+��4 (� w i«F %#$+.-P��� d C�*2P�e�($,2P�%� w��!�«F 0-3+��(�B�e�('��* %$VU"+.20 0� y�y�($*2M33+<(: !2!(,!�$* 0� w����«-5}7 j5��;��$Q\"�,3'��)�� w � �2'+��=(&$4+�<�!3(* %2D� u �N5�� � �R� u��)�$* [U6 !-�(*+.�6-�� �my � &(� � w�w���Q>"-��'���;2'+.-P��� u �d +<�;��#{� u �«F %)� 0-P2L�(<'+B�.+<(H>(� � � �«F %)� 0-P2' 0-'2! 20��#T)�$4��#/+B�*+B<'+��<+<(H>B�('�� w���6 0-3 %$&�0�.+��! %2D� i�4(,$*+.2@(/� i�/U6��+�2L��-320 ��('�� w��0y«F !(* 02@(:+.��-�('�20��#T)�$*�(#/+B�* (� &�('�#/+B�,!��4 (� � �+<-{$4 /�(��(*+�#$ (� i?u« � Ax54� w ��� � w��(�«F+ �$ : m +���B#O��-)�!�<��<+.2 :H\� [>�2%$V>;)3(:���($&�()�3?>(� w(wou«F+���+<(M�0�(@?+����< 0-'-3+�!�#��;��)?>;$*+B��3�(l5�2!(=�r«W@��e56¡ �

y!�«F+ �Q\"�=(&$&�x�L�*2��,�6 +$ d C /�($Q�B>S�;��$Q\� &�&E� }�©�V>x�=(: +#�� w�� �«F+��=(&$4+�<�!3(* %2{�e$,��2M\� � �«F+��=(&$4+�<�!3(* %2^«6�)(&� �$4��(:�"20�(����«6« �¡[� &�u«F+BU� %$Q�*+<(H>+.-{�($42M3'+<(* 02!(,!�$* 0� &xw+.-^2' +�*+���-D� w��?u � w��!�« �FA3AP���}� �!�«F��#S��+.-<��.�"2M\m�(�6 0� u�u+��4�����)(*+.�6-�+.-�@�!��9(:+.2+�%� w �!�-L�(#$ 6�* +$QU6 +$,�+� � �-L�(#$ %�+�P�3+ZUj� �!��* +)L�($&��(:+.��-D� w/y�w«F��#S��+.-P�2'+��=(&$4+�<�!3(* %2D� w��!& 0-P'>�($*20 +#/ !-�(/� w�w+�#T)�$*�()[ +$%� ���

)�$*�)(: 02@(:+<�6-D� w��!& � wouxw�* +)L�($&��(:+.��-D� w��(y«�A'AN� w/�6i�*2�!'2%�)(:+<�6-1�)-�2�(&$&�)+.-'+<-���� i ����� !2!(,�m�('�$*+B�,\"�%� u)i�ª+.-��=(: !+.-D�L5 ��<� %$4(2'+��42%����+�#$ %$+� w/y�y %2�!32/�)(*+.�6-���-�2G [�x)� %$4+. 0-320 (� w��my)�$*�(<��. +# �*���ZU"+.-���� &(�$,!��< %�C�('F�;�($,\� w�*+B#S)��<+.2!+<(H>�� u�C+��Q2'��#{� w��0y�*�. !2!(&$4��#S�(�6-' @(:+.2�+.-�(: +$Q'> %$4 0-'2!

�e���)2M\ }�/�.\� u0y m��!P�* �(: %�=(:+B#/�6-?>(� uxw��)(,$*+<��(/� umy*$* %2��)(:��$+� u0yE��(#O�(3����.\�2/�(�4 ��� u0y��@1��7-5}9l«R� i?u � w�w��!��* �('��4(,$,!'2@(&!�$4 (� w�w�w�*#/ +$,�6 !-�( )P$*��)� %$=(:+. +�%� w��3"!�#O�)-��,�0'> !(H>(� �?u+.-� }«W@ � w���,!�$VU"+BU0�(<'+B�.+<(H>(�;��+!'-�2' +�*+B$&�(<��< W<[ +3L�/U�+<��$.��-�2+.-'2!��#S)P�. !(* 6�,)� 02!+<l,2%�)(:+<�6-D� w���ª-'2/�0)��,!����)(:+<�6-D� w/�?u�ª-'2%$V>;)3(:+<�6-D� w�wou�ª-�2'����+�$,23+.-���� w i�*$,$4��$V:b20��$Q$* 02@(:+<-��720�;2' %�+� i�������6+�$Q2'+.-P��� w i

� �(!��9(H+.-m�4 !2!(*+.�6-2%$V>x)�(M��-L�0�B>;�*+B�%� �!��*�('%(H�e�($4 (* %�4(*+.-��P� &�i� �(!��9(e(:���< %$,��-'20 0� w��$* +�;!3+�$* +#/ !-�(&�%� ���(: !2M3'-'+��"!' +�%� i��� %2�e��7J�}� w � �� +B$* +�e�(�B���%� w�w � w/� 0 � w�w��� ��$,#S�(�N#/ @(&3'�;2��'>��$.�(!3(,3' 0-�(*+.2/��(:+.��-D� 0��'>��$H2%$V>;)3(:���($&�()�33+.2W)�$*�)(:�"20���B�%� 0�� ���

Page 222: Practical Architectures for Survivable Systems and Networks (Phase

'>��$G2' +)[ !-�2L�(<'+B�.+9(H>�� �'>��$G2' +�*+���-D� &�0'>��$J'r�(!��9(e(:�(�. %$,��-'2! (� &�i'>��$G�* !2%!�$4+<(H>(� &)i'>��$G�,)� 02!+<l,2%�)(:+<�6-D� & 0'>��$G�,!P$QU"+BU0�(<'+B�.+9(H>�� 0(�'>��$G�Q>"-'2M3P$*�6-'+B�/�)(*+.�6-�� wou� $* ! ��4�('%(H�e�($* 0� 0?u� $* ! kA"�('%(H�J�0$* � ��!'-�2L��(:+.��-D� 0?u�� !-' %$,�(� *!�<��.+<2}98+<20 0-P�* X� � �9F¡[� 0�� � w%y!�

�65 A'A F� w�� �� 0-' +$&�(�/*!�<��<+.2W98+.2! 0-��4 S� �'�9F¡ � 0��� 0-' +$&�(�<+��0 +220��#T)����*+9(:+.��-D� i2' %)� 0-P2' 0-'2! (� i� +�$,23+.-��X�0�?��+.-P�4(C20�(#S)�$4��#$+��* 0� w i�W9)1�� i(y�'�9*� 0(��6!L�($,2P�%� w�w � w�� 0 }�0#S$4 (�vg���33-D� i � m+< %$,�($*2M3'+<2/�(�D«F +U6 +�.��)P#/ !-�(@� !(,3'�x23���.���0>£� «W@�¡[� w/� � w�� � %#$ %$Q�6 0-�(-)�$*�()[ +$4(:+< %�+� w������(* 0-�23 %2 «W@ �r� }«W@�¡ � w�� �3'+. +$&�($42M3'+.2%�(��2!��#S)����4+<(:+<�6-D� &�i m+< %$,�($*2M3?>�(<��4 0-'2! f�('�� w�&�('��(<��4(,$&��2@(:+<�6-D� w�� � w��Pw�('�2'+�$4 02!(*��$*+< %�+� w�� ��('��.�"2M\"+<-��X)�$4��(:�"20���B�%� w/��('��,!�$VU�+ZU0�(<'+��<+<(H>S$* +�;!3+�$* +#/ !-�(&�%� �0�nA ��A^����>� %$4+.-���� i

m�(���B�e�/>���5m-�2�$4 +�W� � m�($*-'+<-����vg��(#$ %��4(,$,!'2@(&!�$4 (� w���� � w/y�w !P#O��-^�,�0'> !(H>�(�-��-G %#$ %$Q�6 0-�(-)�$*�()[ +$4(H>�� �?u ->;)� %$Q���)(* [�N� w/y!��������©�4(M�)-�2L�($Q2��%� i�����*E � �=(M��-P2L�($,2P�%� i���£-�3' +$*+9(M��-'2! (� &���£-�(: +��$*+9(H>�� �0y

2M3' 02M\"�}'>�($%� w�w#R!��9(:+��< +U� %�*��@19a�V¡[� w���('�<[�"��(&�<�?�(2'+<-���� w�w/y�('�$* %�4��!�$420 %�+� w(w/y�£-�(: +$*-' @(��ª-��6+<-' 0 +$*+<-���E��(�Q\ � ��$*2! |�r���*E � ¡ �&�u�£-�(: +$*-' @( � +>A����2M3L�)-��6 A�K� �W�=¡ � &�u�£-�(: +$*-' @( *$*�)(:�"20�����K� �¡[� w i� nAP���}� �!� � & ��* !2%!�$4+<(H>{�($42M3'+<(* 02!(,!�$* 0� &�uA� 02+!�$*+9(H>{«F��2+!�#$ 0-�(-7{���(2�#S�()D� &(u D %$Q�*+.��- � � �!� � & ��£-�(: +$*-' @( A" 02%!P$*+<(H>85}�,�4��2!+��)(*+.�6-8��-�2 � +>�@1�)-x:�(�6 %#$ 0-�( *$*��(*��2!�����K�=Ax5 ��@ �¡[� &�u�£-�(: +$*-' @( d ��$,#{� u�0 � y�w2'+.2@(:+<�6-L�($V>A�)(4(M��2M\5��-{)��(�,�V�;��$Q2��%� � 0 [�x)��<�6+<(,�G#/+B�,�*+<-��X<���!'-�2��C2M3' !2M\� � �+��B��!��=(&$&��(:+.��-��('�Ux!P�.-' +$&�(<'+B�.+9(:+. +�%� y�w-'�$ [�x)��.+<20+9(.�(!3(,3'��$*+9(H>g$4 %�"!'+�$4 %2D� y?u�£-�(: +$*��)� %$,�(<'+��<+<(H>(� &� nAP���}� �!� � & ��H�*�(���)(*+.�6- [�� 02+!3(:+<�6-D� wou(�lL$* [�J�0�����+� 0!�+.-L�02' %�"!L�)(* (� w��\� +$*-' +���%� w�� & � w/y�w � w�� �#/ !2M3L��-'+B�,#T�%� w���0-' !(H�1��$Q\"+<-���� w��(y!��* +$V:H�()�)��<+.2/��(:+.��-D� w�w(w�.$&�()P)[ +$,�%� 0!��HE{A y � 0(y�HE{AP���}� i!&

g��/U0�P� wouxw«F +U� %�.�()�#/ !-�( � +9(���g�« ��¡[� wouxwA� 02+!�$*+9(H>�@1��-L�0�6 %$��hg�A�@�¡[� wou(u F+B$4(&!��(�l@1��2M33+.-' S��g0 6@�¡[� w�uxwg��6+<-�(.5m+�$Q<[��$4-' Ax� �6� � E5}$*2M33+<(: !2!(,!�$* O��g(5FAx56¡ � w��(yg��6+<-�(.Eo 02M33-'+.2%�(�l5}$*2M33+<(: !2!(,!�$* S��g(EF56¡ � w�� &g�A�@ª� wou(u�W�($,�� %$%����(!��2'+��42%$4 !(:+<�6-L�($V>A��2!20 +�,��2!�6-�(&$4�����+� wouxw

���

Page 223: Practical Architectures for Survivable Systems and Networks (Phase

� %�B�. %$+� { %�. !-D� �?u� %$Q<[ +$*���+� 0 � � w�w/�� %$4-' %�B��($*2M33+<(: !2!(,!�$* 0� w��@19oAN� w�w � w��!& � w(w�w�* !2%!�$4+<(H>�� w�� &�* +)L�($&��(:+.��-D� w��!&� +>A#S��-L�0�6 %#$ 0-�(/� w�wou� ��2M33 %$%����(!��2'+B�[ %$4 0-�(:+��(�6)��o�1 %$���-L�0�B>;�*+B�?��- 2+$Q>;)3(:�P�

�!�(:+B#/+<-��X�)(4(M��2M\"�C�6-2%$Q>;)3(*����$,�()�3'+<2{+B#S)P�. %#$ 0-�(&�)(:+<�6-��%� �!�9 � )�3�(/� � ��,�<+.-�(/� 00y9l�(#T)��*�6-�� �e!3(,�. %$ d CZ� w�� �20�6-�l,-' %#$ 0-�(%� w�uxw � w�� �2%$V>x)�(:����$,�()�3?>�� w�w�uAP«�Ax�M� w�w/�9l���YEG�0 0� w�� &98 /�(�=({20��#T#/��-A#/ !2M3L��-'+B�,#{� w��(y98 /�(�=(-)�$*+ZU�+B�. +�6 (� w����98+.-'2!���.-�� ���(&$*+<2M\g54C

�=>;�/��-�(*+.-' �2%�<��2M\"�+� wou98�?�(2'+<-��2P>"-L�(#$+.20� w�w i�('�$* %�4��!�$420 %�+� w(w/y98��2M\�+<-��3'+. +$&�($42M3'+.2%�(�§� w��@1�(!P2' (� i(y@� %�(2'���.�%�N�J�)(,3' %$4+.-' 0� 0�� � w����@1�*�,�M� w(w��@� !+.-'2M\) (�N�e3L�($Q�. %��,!�$VU"+BU0�(<'+B�.+<(H>S�4(,!�2P>(� �@� @(&$*+<2%�+� i��@�+B���. !-D�,g���-L�)(&3���-D� w/y �$* +�* /�0$*2M3 2!�6-�(&$4+�<�!3(*+.�6-P�%� w�����,!�$VU"+BU0�(<'+B�.+<(H>S$* +�* %�($*2M3D� 0�� � w/y!�@�+B�,!��4 I2' @(: !2!(:+<�6-D� w�u@���<3+��. �20�;2' (� w�� � � w�w i2P>"-L�(#$+.26�<+.-�\�+.-P�X��-�2{�.�?�02'+.-��P� w�w i�* !2%!�$4+<(H>{�($42M3'+<(* 02!(,!�$* 0� w�w i

�* !2%!�$4+<(H>G20��-�(,$*���B�%� w(w i�* !2%!�$4+<(H>^$*+B�,\"�%� ��i@��6-3+<(:�($*+.-P��� w�w �@���$Q$*+B�%� �;��<2'+.2@(:+<�6-L�($V>A�)(4(M��2M\"�%� ��0@���$Q$*+B�%�7C��<[ +$4(.E��()�)L�)-D� u�0@ AP9*�j@�!P�<(:+B)��. }�*+.-P���. :H�. [U6 +�§� w/�6i@�!��9(:+<2%�%� w��!�2'��#S��+.-P�%� wou;w\� +$*-' +��$4 %2' +�*+���-^'>�($-@19oAN� w��!�$*+<-����%� wouxw!��* �('��4(,$,!'2@(&!�$4 (� w�w�w@�!��9(:+B�. +U� %��/U(�)+����0<'+��<+<(H>��§@�9l58¡[� w��+.-�(: +��$*+9(H>£��@19a�V¡[� w�� � w�� 0�* !2%!�$4+<(H>ª�§@�9�AP¡[� w�� � w�� 0�,!�$VU"+BU0�(<'+B�.+<(H>��§@�9 �6¡[� w�� � w/y � w/� 0@�!3(,!L�(�a�Q!��,)'+<20+<�6-D� w�w�}�0�?�($K�Q!3-L�P� y�i�}��(:+.��-L�(�*�£-P'K$,�(�4(,$,!'2@(&!�$4 ,*$*��(* 02!(*+.�6-��; 0-�(* %$� � � ��G¡ � w � ��}��(:+.��-L�(�a7C %�4 /�($42M3��;��!'-320+���$* %)���$=(&��;��#T)�!3(: +$,�-�)( 7C+��,\� 0�e$Q>;)3(*����$&�0)�3?>N�v�~7C���< P+.- A� !2%!�$4+.-��X(&33 �£-P'>��$,#S�)(*+.�6-?A��"20+< !(H>(� 0E�$Q!��4(m+.-��=>;<� %$,�Q)L��2! (� 0�}��(:+.��-L�(�a7C %�4 /�($42M3�9l�(<���$&�)(*��$Q>@ AP9� [���($4(&�+� w��6i�m !2%!����P� � 0��$Q�6 *3L« (,3' %�4+��%� w�u(�

�m ! %2�3��(#��7C���6 +$2%$V>x)�(:����$,�()�3?>�� w�w�u�m ! %2�3��(#Y:\A�2M3�$4�� +2' %$+� &0� � w�w���m @(H�;�($,\�+.-��P� w(w���m +!�#S��-'-D��o !(: +$ �XC

m��!P�* 1g(!�2'+<20+��0$Q>8�;��#S#$+<(4(: ! �(: +�4(*+�#$�6-'+. +�%�u�0A� 0-��)(: �(: +�4(:+B#/��-'+. +�%� &��

�m [�;2%�(�4(,�. «F+��=(&$*+B<�!3(* %2�A� 02+!�$* kA;>;�4(* %# �r«�A'A�¡[� w��6i� � ��}� i!��-5 �W9F� � � +>R«F !(: +$,#$+.-L��(:+.��- *$*��(*��2!���§� &�u

�!¹

Page 224: Practical Architectures for Survivable Systems and Networks (Phase

�8<;�4 02@(Q:b��$*+< 0-�(: +2�)L�0$&�(2'+B��#{� &�� � w��?u�(<��=(&$&�)2!(:+<�6-D� & � 0-'2%�()��Q!����)(*+.�6-�� &��+.-�33 %$*+9(M��-320 (� &��)[�(�B>;#/�($,)�3'+B�,#{� & ��8<��*2+!�$*+9(H>��,+ ��� ��u � � � � 0Pw � 0(y � 0!� � 0 &�8)[ !- �6$*�(!�)D� i���8)[ !- A"��!�$*2! �$4����$,�(# ���$20 I� ��A �X� w/�6i�8)[ !- A"��!�$*2! W�*�('%(H�e�($* 0� 0���8)[ !- A">x�=(: +#S�-E��0�,\ � ��$420 S����AxE � ¡ � w��(y�8)[ !-x:H<��/�^�*�0'%(H�J�($4 (� 0Pw [�P�(#T)��. +�%� 0��#/�)(:+BU0�)(*+.�6-�� w��(u$*+B�,\"�%� 0 �$*��<P!��4(%� 0!&�8)[ +$&�)(*+.�6-��(��)�$,��2!(*+.2! (� iPw��-L�(�Z>;�*+��+� iPw20�6-�(,$*���B���(<'+B�.+9(H>�� w����$* +�;!3+�$* +#/ !-�(&�%� �?u$*���< +.-^�,!P$QU"+BU0�(<'+B�.+9(H>�� 0��AxE � � w��0y�8!3(&�4��!�$420+.-P��Q>;�4(* %# �(2�#$+.-3+��4(,$&�)(*+.�6-��?��+ZUN� �(���0$*-L�(�+�«6�/U�+B2{9�C¬"¤�¨M¤e$* +���)(*+.�6-�� i /�($Q�B>O)L�()� %$,�+� & & 0-���+.-' ! %$*+<-��Y2'+��420+B)��.+<-' (� &��+.-P'>�($,#S�)(:+<�6-O3'+B2'+.-P��� w/y?���0�,�Q�1��$Q2��587 ��0�� : w i )[���<+.2[>�� w��xw�)(*(&��2M\"�%� �!&2/�()�(&!�$4 �<?>^EF$*�m�,�)-�3'�($,�* 0� y?��eE{A'A? �x)[���Q!�$* 0� w�&2' 0-3+��(� :£�('�:]�* %$VU"+.20 8�)(*(&��2M\� u &2'+.2@(:+<�6-L�($V>g�)(4(M��2M\� � 0 � y�yg(E�5 � C � )����.+<2+>(� w��?u�6-' :b(:+B#/ 0� 0 �)�$* ! 0-'2+$Q>;)3(*+BU6 4��-L�(�Z>;�*+��+� y�w�*-'+ �$-���� wou�0���(&$*+<��(2%�<��2M\g2P$*+B'%(%� u ���@��J)�$4��<��. +#S�+� u0y��G�e�

'>�����<���J:£�6-��+� i!�+.-P'K$,�(�4(,$,!'2@(&!�$4 W�,!�$VU�+ZU0�(<'+��<+<(H>(� 0��$,����-'+��%�)(:+<�6-L�(�� 0-�(*+<(:+< %�+� i!�$* +)[��$=(/�P�N� � � w � �$* +�* /�0$*2M3�$4 020�(#S#$ 0-�2��)(:+<�6-��%� w/y"u�«6« : �?u � i ��«6« : ��� � i �� !-�(:+�!P# � �.�?��(:+.-P�X«F+BU"+�23 }��/�W� w�&� +$Q'>��$Q#O�)-'20 ��202! %)3(&�(<��< �23 %��$,�(2L�)(*+.�6-D� w���(�-�X�,!�<�$4 %�"!'+B$* %#$ 0-�(%� � �2' %)� 0-P2' 0-'2! k�6-�� w��$* +�;!3+�$* +#/ !-�(&�%� � � �(�(&3�$4 /�)(,�%� y!�� +$*+B#/ @(: %$�('��,!�$VU�+ZU0�(<'+��<+<(H>(� w�w�w�('o(&$,!P�4(H�1��$4(,3'+.-' +�,�+� w/y � w�w�w � F� 0 ���(�B>;#/�($,)�3'+B�,#{� &����($,$&�0�%��*3'+��B�.+B)D� w%y!���($4(M�0<��. �20�(#S)�!�(:+.-P��($*2M33+<(: !2!(,!�$* 0� w�u(�)���$4(&�(<��. 2!��#T)�!3(:+<-���� w��!�*$* +2L�)(:�($��@��J)�$4��<��. +#S�+� u0y*$* +�*+�23 0-�(/�v� �;��#S#$+��Q�*+<�6-��6-{�e$4+<(*+.2/�0�j�£-x'K$&�(��:(&$,!32!(&!P$* *$*��(* 02!(*+.�6-T� ��G�e� =¡ �/��� w����*$* [U6 0-�(*+.�6-�('�20��#T)�$*�(#/+B�* (� &�('�#/+B�,!��4 (� �0y*$*+<-'20+B)��. +�'>��$G�* !2%!�$4+<(H>(� w/� ��. %�(�4(C2!��#S#$�6-^#$ 02M3L��-3+��,#{� w��0y�. %�(�4(.)�$4+BU"+��< %�6 0� w��(���<;�4 !2!(Q:b��$*+< 0-�(: +2D� &���('�2%$Q>;)3(*����$,�()�3'+<2�)P$*��(*��2!�����+� 0���* +)L�($&��(:+.��-D� w��(y�4(,$,!'2@(&!�$,�(�§� w��xw*$*�"2!(*��$%���{��$,#S��-�/U6�6+B2'+.-��$20��U� %$4(m2M3L��-3-' %�B�%� � � � w��6i � w��?u �w�� �*$*�"2%!�$4 %#$ 0-�(/� � 0*$*�"�('�:£2%�($,$V>"+.-���20�;2' (� w(w � &0y � 0�� � w�w/y � w�w i �wou(�

� 3

Page 225: Practical Architectures for Survivable Systems and Networks (Phase

*$*��)P$*+. @(M�($V>52!�x2' 0� 0Pw)�$*�(<��. +#S�+� �!&*$*��(*��2!�����+� w�w��587 N5m-' !(-$*�(!3(:+<-���� w��

�=>;�/��-�(*+.-' 0� w��2%$V>x)�(:����$,�()�3'+<2(� �!� � &(� � 0(�« �FA'Ax�=�}� � �'>��$H-' @(H�;��$Q\"�%� �(y� � D %$Q�*+<�6- � � �!�� �U;!��.-3 %$&�0<'+��<+<(:+< %�+� w i-' 0 +2�'>��$G�Q!�$QU"+ZU(�0<'+��<+<(H>�� y � & � � w��!&!'-��4 02%!P$* k+<-�(: %$,��2!(*+.�6-P�.�(#/��-���� &�&!�)���$,�(2' +2D� w�w��nA ��AN� w��!�3'+. +$&�($42M3'+.2%�(�D����>� %$4+.-���� i��<;�4 !2!({��$*+< 0-�(M��(:+.��-D� &��!��* �('��4(,$,!'2@(&!�$4 (� w�w�w*!�<��<+.2[:]\� [>�+.-P'K$,�(�4(,$,!'2@(&!�$4 S� �6�V¡[� &(�7-��+.-"<��o��<�����\"�+²�E-�HAx�=�}� i!&7-��-�2' +���§� �e$*+���-�m [�;2%�(�4(,�. I«�A'AN� w���i$* +�.+��0<'+��<+<(H>T��-�2{�* !2%!�$4+<(H>(� w�� ��4(,$,!'2@(&!�$4 (� w���� � w/y�w7C /�(2x:b�6-��Z>g#$ %#$��$Q>(� w�� 07C /�(� :b(:+B#/ ��202!��!'-�(M�0<'+��<+<(H>�� ��i�/U(�)+����0<'+��<+<(H>�� ��i7C 020��-3lL��!�$,�)(:+<�6-��-�(:+<20+�)��)(:+<-��k(&33 2!�6-��4 %�"!' 0-320 %�+� &0y�(�-�R�,��� )�$4��)[ +$4(H>(� 0(�7C 020��U� %$Q>587 N5m-' !({20�(�����0)��* 0� u�u5*EC�6E A'A & � u�u2' %�4+��6-{�6�?�0�§� w/���*����-x: i � w/� 0)�$*+<��$*+9(:+< %�%� ���(&$Q!��4(H�1��$4(,3?>�� w�w/y7C 020��U� %$Q>{<��<��2M\"�+� w�� � w�w/�7C %�.+��(<'+B�.+<(H>(� y�(�-�X�,!�<�$4 %�"!'+B$* %#$ 0-�(%� � ���!3(C�('�!'-�$4 %�.+��(<��< �20�(#S)��6-' !-�(,�%� w��(&3�$4 /�)(,�%� y�y7C %#$ %2'+��)(:+<�6-

� u �N20�;2' (� ���7C %�"!'+�$4 %#$ 0-�(&�'>��$.�/U0��+����(<'+��<+<(H>(� y'>��$G)� %$Q'>�($,#S��-'20 0� � � y�i'>��$G$* +�.+��(<'+��<+<(H>(� y � y�i'>��$G�* !2%!�$4+<(H>(� y � y�i'>��$G�,!P$QU"+BU0�(<'+B�.+9(H>�� y6i+.-�(: +$,2' +)[ !-�2' !-'20+< %�%� y�i��)� %$&��(:+.��-L�(�§� �?u � i�u � w��6i7C %�* %�($*2M31��-�2{2' +U� %�<��)�#$ 0-�(/� i��2'+�$4 02@(:+.��-��%� w/�!&7C %�*�(!�$*2! I<����)(&�.���(2'+.-P��� w(w/y7C +U6 +$,�4 k 0-P�6+.-' ! %$4+.-��)�$*�)(: 02@(:+<�6-{�(�?��+<-��4(%� �0y7C +U6�"2/��(:+.��-�('�#/��<3+��. �20�;2' (� w�w i � wou�u7 � �e�+� &�u7C+.-����H�0'�)�$4��(: !2!(*+.�6-D� w��!&7C+��,\"��(<��4 0-'2! k�('�+.-�(: +���<+��6 !-'20 0� &��2/�(!P�* %�+� u)i +�[ 02@(&�%� u�i+.-^2' [U6 %�<��)�#$ 0-�(/� �!&+.-^\� [>^$* !20��U6 +$Q>�� �!�+.-^!��4 %�{�('�2+$Q>;)3(*����$&�0)�3?>�� 0+.-�2P!'20 +2D� � &+.-?U6�(�BU"+.-��Y�Q!�$QU"+BU0�(<3+��.+9(H>�� �?u#/�(<'+��< F20�;2' (� ��i-' 0 +2�'>��$G!3-�2' %$Q�4(&��-�2'+<-���� � 0�('�7 � +.-�(* %$Q'> +$* !-'20 0� u;w��U6 %$4 %�=(:+�#S�)(*+.�6-D� w/y?�$* +�*+�2P!L�(�§� w/y"u�*��!P$*20 +�%� u(�!'-�2' +$* +�4(:+B#O��(:+.��-D� w/y?��;�($,�* !-'+.-P��� w/y�y7C+��,\"� � ��$,!P#�� u�0 � �!� � i � � w���i7C+BU6 +�4(%�7{�6-AP«�Ax�M� w�w/�7C+BU6 +�4(V:=Ax3L�0#/+B$V:H5 2��. +#O�)-£��7mAx56¡ � w�wou7C��!3(: +$,�+� w�w��7mAx54� y�y � w�wou7mAxE �HE{A y � 0(y7.!'-x:b(*+�#$ F2M3' !2M\;�+� w�w �0º

Page 226: Practical Architectures for Survivable Systems and Networks (Phase

7.!��,3"<?>��[g���3'-1@ªC+��4�����)(*+.�6-O\� %$4-' %��� w�� ��m [�;2%�(�4(,�. I«�A'AN� w���i

AP�(�9(&�! %$%�,gPC �CB� w�� �AP�/>;2m�,�($4+§�vAP�0#/+�� w/y!�A�2%�(���(<3+��.+9(H>�� &A�2M3'�()[ !-�3L�(!' +$%�5}$=(&3"!�$�6 0-3 %$&�0�.+<(H>SU;�%CD [�x)� %$*+< 0-'2! (� w��6i � w��0yA�2M3�$4�� +2' %$+�N@�+.2M3L�) %�l«RCZ� w��!�*3L« (,3' %�4+��%� w�uxw)�$*�)(: 02@(:+<�6-D� w�� �A�2+$,!3(&�(<'+��<+<(H>(� w��!�AP«�Ax�M� w(w��A� %�0 F+< +�W� w�� �!��* �('��4(,$,!'2@(&!�$4 (� w�w�wA� !2%!�$4 ,*!�<��.+<2 � [>��£-P'K$,�(�4(,$,!'2@(&!�$4 £��A �6�V¡ �

w�w��A� !2%!�$4+<(H>�� y�(�-�X�,!�<�$4 %�"!'+B$* %#$ 0-�(%� �0��)(*(&��2M\g#$�x23 %�%� y��<?>G��<��*2+!�$*+9(H>��,+ ��� �?u � � � � 0Pw � 00y � 0!� � 0 &\� +$*-' +���%� w�w � w��!&#R!��9(:+��< +U� %��2��)(M�(<��(�* +�%� w�w#R!��9(:+��< +U� %�a@�9�AP¡[� w��(&3�$4 /�)(,�%� �?uA� +�B'�:H�V>"-'2M3�$*��-'+��%�)(:+<�6-D� w��A� +)L�($&��(:+.��-\� +$*-' +���%� w�� &�('�2'��#S��+.-��+� w��(y�('�2�!3(:+< %�+� w��(y�('�)[���<+.2[>g��-P2�#$ 02M3L�)-'+��Q#�� w/����('�$*���< %�%� w����A� +$QU6 +$lL�. +�%� w�w%y-L�(#$ %�+� w�w/y-' !(H�1��$Q\j� w�w��AP�nAx58@1�G� w(w��A�+B��\�:H)�!P$,�* 6�4���W����:£ /�0$ #$ !(&�()�3'��$+� w����A�+B#S)��< *�;�6-�(,$*����EF$&�)-��,#$+��Q�*+.��-'�$4��(:�"20�(�L��AP�eE =¡ �&�uA�+B#S)��< }«F+B�4(,$*+�<P!3(: +2GA� 02+!�$*+9(H>O�£-x'K$&�(�=(&$,!32!(&!P$* ��AP«�Ax�V¡ � w�w��A�+B#S)��< W@1�(!P2' (� i(y

�,�<+.-�(/� 0(yA��('%(H�e�($4 'r�(!��9(C+.-m�4 !2!(:+<�6-D� &�i�8)[ !- A��(!�$*2! (� 0����)� 0-x:]<[�/�N� 0��A��('%(H�e�($4 f !-��6+.-3 0 %$4+.-��P� &��A �6�M� w�w��A"(&��2M\ �W!L�0$,2D� 0(yA"(&��-�2L�($Q2��%� i?uA"(&�($,�<+���3�(G�£-�(: +$&��2@(:+ZU6 I9Z+<-�\� w��6iA"(,$,!'2@(&!�$4 �($*2M33+<(: !2!(,!�$&�(��� w������$,����-'+��!+.-��X)P$*+.-320+�)P�. %�+� w��xwAx!�$VU"+BU0�(<'+B�.+<(H>�()�)��<+.2%�)(:+<�6-D� �(��(�-��-? %#$ %$,�� 0-�(-)�$*��)� %$=(H>��P��+§� w�� � ����(�-��-?�oU� %$,�(���D�V>;�4(: +# )�$*��)� %$=(H>�� � &2/�(�4 I33+��4(*��$*+< %�H�('���!3(&�(�6 +�%� u�u20��!P$,�* -'��(* %�+� w��(� � w � �2%!�$Q$*+<2%!����P� w/y�&2' !l'-'+<(*+.�6-D� u2' %)� 0-P2' 0-'2!+. +�%� w�� 0-�(: +$,)�$4+��4 (� �(�+.-P'>�($,#S�)(:+<�6-D� �(�#R!��9(:+��< +U� %�§� w�� � i0y#R!��9(:+��< +U� %�*��@19 �W¡ � w/y � w�� 0-' !(H�1��$Q\j� �(�)[ +$*+B#/ @(: %$+� w�w�w$* +�;!3+�$* +#/ !-�(&�%� ��u$*+B�,\"�%� �?u�,!�<P$* %�"!'+B$* +#/ !-�(,�%� �(��Q>;�����(<�!��+� w/y�&�Q>;�4(* %#{� �(�(&3�$4 /�)(,�%� �?u�C+<(,3��6 !-' %$,�(�.+B�0 +2{23 %)� 0-�2' !-'20 0� w�uA;>;�����(<�!��J'>�($G�,!�$VU�+ZU0�(<'+��<+<(H>(� w/y�&A;>"-'2M3�$4�6-'+B�/�)(*+.�6-2%�<��2M\� wou'>��$,#S�(�D#$ !(,3'�;2��%� w�u$*+B�,\"�%� �(y$*��<P!��4(%� w���* +�B'�� w��(:+B#/ :b(&$4+����� %$* +2D� w�uA;>;�4(* %# 2' [U6 %�<��)�#$ 0-�(

� �

Page 227: Practical Architectures for Survivable Systems and Networks (Phase

'r��+��B!�$* +�%� �!&)�$&�)2!(:+<20 0� & �EF5 � �V@ª� w ���E��(#S)� %$Q)�$*�"��l,-P��� �0yE����YE� 4�e3'+.-P��� w�� &E-� �}� w��!&'>��$-@19oAN� w���0�.+B#/+9(M�)(*+.�6-��+� wou����U6 %$4 0-�23�o�1 %2�� w��!&�*+B�0 (� w(w�wE-�HAP���}�L�3+ZUj� i!&��202!��!'-�(M�0<'+��<+<(H>�� wou�u�(!�2'+9(:+<-���� w�u�u20 !-�(,$&�(�<+��! %2^U�+< +�W� w�� &+.-'2!��#T)��. @(: 0-3 %�,�+� i 0+.-�(: +$,)�$4 !(&�)(:+<�6-��%� w��Pw�.+B#/+9(M�)(*+.�6-��+� i!&Eo %$&�0#O��20� � 0Eo %�4(*+.-��P� &�iEG3'��#T)��4�6-D� � 0-�a2!��#S)3+��. +$JEF$*�m�,��-^3'�($,�* 0� w�& � � 0 � 0 �2'+.2@(:+<�6-L�($V>g�)(4(M��2M\"�+� ��0EG3�$4 /�)(,�(:�Y)� %$Q'>�($,#S��-'20 0� y!�(:�Y$* +�.+��(<'+��<+<(H>(� y(y(:�Y�* !2%!�$4+<(H>(� ��u(:�Y�,!P$QU"+BU0�(<'+B�.+9(H>�� ��uEo���. +$&��-'2! �('�20��#T)�$*�(#/+B�* (� &�('F'r�(!��<(,�%� y�('�3;!P#O��-^'>�6+B<��. +�%� w��(�EF$&��-��,��2!(*+.�6-P�'K!��<l�����#$ 0-�(%� w��EF$*�m�,��-{3'��$Q�* +�%� �6iEF$,!��=(/� �EF$,!��=(m+<-��=>x<� %$Q�,)L�)20 (� 0EF$,!��=(: %24�;��#T)�!3(* %$oA� !2%!�$4+<(H>6��U0�(�B!L�)(:+<�6-W�e$4+Z:(: %$4+��{�r�4 0 WE-�HAP���G¡[�L��+BUj� i!&EF$,!��=(: %2��;��#T)�!3(:+<-�� �J�(�4 g�K�* ! �E-� �J¡[� w��!&EF$,!��=(: %2�)L�)(,3�(<��4 0-'2! f�('�� �(y'>��$G<L��2M\"!�)1��-�2{$* @(&$*+< +U0�(��� w�w/y'>��$G<�����(,�.�?�02'+.-��P� w�w%y

'>��$G$* !20�6-�lL��!�$,�)(:+<�6-D� w�w%y$* %�(�.+B�/�)(*+.�6-D� w�w/y$* +�;!3+�$* +#/ !-�(&�%� �0yEF$,!��=(H�;��$=(&3'+<-' %�Q�%� � 0-�3���-'20 +#/ !-�(/� i�.�"2/�(�<+��! %2D� w�����('�<L��2M\"!�)D� �(y)[ +$*+B#/ @(: %$+� w/y � w�w�w!'-�\�-'���C-D� wou1m-P2' %$Q�6+�$Q2'+.-��P� w i1m-3+<l, +2 �e$Q>;)3(:�(�.���6+<2�5 $*2M3'+9(: 02@(&!�$4 � 1}�e56¡ �

w��(y1m-3+B'>��$Q# �;��#T)�!3(* %$��£-x'>��$,#S�)(:+<�6- EF$&��-P�&��2 :(:+.��-��G5�2@(R� 18�e�HEF56¡ � y � ��(�<+.20 +$4(%� &(� ��(�<+�2L�)(*+.�6-g�(!3(&33��$*+9(:+. +�%� &(� F+B�6-L�P� ��+<�oU0��-3-'+§� wou(� F+B$,!��4 %�+� y?ud �(�6-' +$%�«6�/U"+�2D� 00yd �(�.2+�/�(\����0!��§� w%y!�d �(������2M3D�L«6��-�ANCg�A�@ª� wou�u*3L« (,3' %�4+��%� w�u(�d �($* 0� d +����<+��+� w�� �d +�$4 %�< %�,��($*2M33+<(: !2!(,!�$* 0� w�u(�2M3L�(�B�. 0-P�6 %�+� &(��W�<��<L�(�D@���<'+B�. 0� &(�)[�($4(M�0<��. 2!��#S)P!3(:+<-���� w/�!�)[�)(: 0-�(*+��(�B�%� &xw$* +�;!3+�$* +#/ !-�(&�%� �!� � w��?u(&3'+<-x:£2+�.+< 0-�(G�Q>;�=(: %#T�%� w�w/�(&3�$4 /�)(,�%� � �d �W7.54� w/�!� � w�w id �.  �6��7-5I� w(w id $&�()�)� %$Q�%� w�w��d $*+<(* [:b�6-'20 0�L$,!'-;:���-?>"�.3' %$4 g� d �67.56¡ � w��!�d $*+<(* [:b�6-'20 0��U6 +$*+B'°>?:b�6-'20 0� 0-'2%�()��,!P���)(* (�$,!'-;:���-?>"�.3' %$4 � d �.  �6��7-58¡[� w�w i

� �