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1) A8 and A9 interface lies between BS and PCF on cdma patch path.2) A8 is about data3) A9 is about signaling4) A8 and A9 interface is shown below

5) basic call flow between BS(AN in evdo) and PCF is shown below. It wont be much differentin cdma-2000

AT BS PCF PDSN---session est------->

-------- A9 setup-A8-----> ------A11 Reg request ------------>

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7) stack details for A8 and A10 is given below.

8) We end up having different state machine for A9 based on call flows on this interface.9) GRE keys between BS and PCF may be different from GRE keys between PCF and PDSN,

so when we establish session in CAE with A9 messages, we would be seeing GRE keys inA9 for GRE tunnel between BS and PCF. So data processing would remain same. But theremay be some changes in control path processing inside kdp based on A9 state machine andhow cae is going to deal with A9 messages

10) A8 connection is released when session moves from active to dormant unlike A10 wherea10 connection is maintained even when session during transition from active to Dormant.This is like preservation cases in UMTS, bit more complicated than A10/A11.

11) meid will be available in A9 messages12) cell identifier is available in A9 messages13) imsi is available in A9 messages14) some of the vendors can use very proprietary interface between BS and PCF (we need to

figure out what kddi uses this. Like last time, if they provide specifications, it would begreat)

15) Data path processing at simulators would be very minimal, but we need A9Sim in simulators16) some effort is required from QA in qualifying A9Sim , but much less than 4.0 ci

qualification and 2.9.6 Sim qualification.17) Based on conversation with kumar last time when he visited Bangalore, band width

monitoring is required for every one second unlike existing implementation at netmon. Soserious effort is required at netmon if we understood requirement correctly

18) From QA side, 2 months time is required to deliver release (on telco) with decent qualitywith 3 folks, these 2 months does not include time taken to stabilize simulators

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19) QA-1 takes care of netmon testing, QA-2 takes care of signaling,control plane testing andQA-3 takes care of rest of testing.

20) QA needs to come up with A9 message based call flow scripts similar to A11. But justeffort , no risk

21) 3GPP2 A.S0016-D v3.0 deals with A9 interface.