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Chapter 1: What is a Network?

o Introduction 

o Local Area Network

o Metropolitan Area Network  

o Wide Area Network  

o Advantages of a School Network  

o Disadvantages of a School Network  

Chapter 2: Protocol

o Introduction o Ethernet 

o Fast Ethernet

o Gigait Ethernet 

o Local!alk  

o !oken "ing 

o FDDI 

o A!M 

o Su##ar$ 

Chapter 3: Hardware

o Introduction

o File Server

o Workstations

o  Network Interface %ards

o %oncentrators&hus

o "epeaters

o 'ridges

o "outers

Chapter 4: Cabling

o Introduction

o (nsheilded !wisted )air *(!S+ %ale

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o Sheilded !wisted )air *S!)+ %ale

o %oa,ial %ale

o Fier -ptic %ale

o Ethernet %ale Su##ar$

o Wireless LANs

o %ale Installation Guidelines

Chapter 5: Topolog

o Introduction

o Linear 'us

o Star

o Star.Wired "ing

o !ree

o %hoosing a !opolog$

o Su##ar$ %hart

Chapter !: "o#tware

o Introduction

o )eer.to.)eer

o %lient&Server

o E,a#ples

$lossar%wards

What is a Network? 

A network consists of two or #ore co#puters that are linked in order to share resources*such as printers and %D."-Ms+/ e,change files/ or allow electronic co##unications0

!he co#puters on a network #a$ e linked through cales/ telephone lines/ radio waves/

satellites/ or infrared light ea#s0

!he three asic t$pes of networks include1

• Local Area Network *LAN+ 

• Wide Area Network *WAN+ 

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Local Area Network 

A Local Area Network *LAN+ is a network that is confined to a relativel$ s#all area0 It isgenerall$ li#ited to a geographic area such as a writing la/ school/ or uilding0 "arel$

are LAN co#puters #ore than a #ile apart0

In a t$pical LAN configuration/ one co#puter is designated as the file server0 It stores allof the software that controls the network/ as well as the software that can e shared $ the

co#puters attached to the network0 %o#puters connected to the file server are called

workstations0 !he workstations can e less powerful than the file server/ and the$ #a$have additional software on their hard drives0 -n #ost LANs/ cales are used to connect

the network interface cards in each co#puter0 See the !opolog$/ %aling/ and 2ardware 

sections of this tutorial for #ore infor#ation on the configuration of a LAN0

Wide Area Network 

Wide Area Networks *WANs+ connect larger geographic areas/ such as Florida/ the

(nited States/ or the world0 Dedicated transoceanic caling or satellite uplinks #a$ e

used to connect this t$pe of network0(sing a WAN/ schools in Florida can co##unicate with places like !ok$o in a #atter of

#inutes/ without pa$ing enor#ous phone ills0 A WAN is co#plicated0 It uses

#ultiple,ers to connect local and #etropolitan networks to gloal co##unicationsnetworks like the Internet0 !o users/ however/ a WAN will not appear to e #uch

different than a LAN or a MAN0

 Advantages of Installing a School Network 

• "peed0 Networks provide a ver$ rapid #ethod for sharing and transferring files0

Without a network/ files are shared $ cop$ing the# to flopp$ disks/ then carr$ing

or sending the disks fro# one co#puter to another0 !his #ethod of transferringfiles *referred to as sneaker.net+ is ver$ ti#e.consu#ing0

• Cost0 Networkale versions of #an$ popular software progra#s are availale at

considerale savings when co#pared to u$ing individuall$ licensed copies0

'esides #onetar$ savings/ sharing a progra# on a network allows for easier

upgrading of the progra#0 !he changes have to e done onl$ once/ on the fileserver/ instead of on all the individual workstations0

• "ec&rit0 Files and progra#s on a network can e designated as 3cop$ inhiit/3 so

that $ou do not have to worr$ aout illegal cop$ing of progra#s0 Also/ passwordscan e estalished for specific directories to restrict access to authori4ed users0

• Centrali'ed "o#tware (anage)ent0 -ne of the greatest enefits of installing anetwork at a school is the fact that all of the software can e loaded on one

co#puter *the file server+0 !his eli#inates that need to spend ti#e and energ$installing updates and tracking files on independent co#puters throughout the

 uilding0

• *eso&rce "haring0 Sharing resources is another area in which a network e,ceeds

stand.alone co#puters0 Most schools cannot afford enough laser printers/ fa,

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#achines/ #ode#s/ scanners/ and %D."-M pla$ers for each co#puter0 2owever/

if these or si#ilar peripherals are added to a network/ the$ can e shared $ #an$

users0

• +lectronic (ail0 !he presence of a network provides the hardware necessar$ to

install an e.#ail s$ste#0 E.#ail aids in personal and professional co##unication

for all school personnel/ and it facilitates the disse#ination of general infor#ationto the entire school staff0 Electronic #ail on a LAN can enale students to

co##unicate with teachers and peers at their own school0 If the LAN is

connected to the Internet/ students can co##unicate with others throughout theworld0

• ,le-ible %ccess0 School networks allow students to access their files fro#

co#puters throughout the school0 Students can egin an assign#ent in theirclassroo#/ save part of it on a pulic access area of the network/ then go to the

#edia center after school to finish their work0 Students can also work

cooperativel$ through the network0

• Workgro&p Co)p&ting0 Workgroup software *such as Microsoft 'ack-ffice+allows #an$ users to work on a docu#ent or pro5ect concurrentl$0 For e,a#ple/

educators located at various schools within a count$ could si#ultaneousl$

contriute their ideas aout new curriculu# standards to the sa#e docu#ent andspreadsheets0

Disadvantages of Installing a School Network 

• +-pensi.e to /nstall0 Although a network will generall$ save #one$ over ti#e/

the initial costs of installation can e prohiitive0 %ales/ network cards/ andsoftware are e,pensive/ and the installation #a$ re6uire the services of a

technician0• *e0&ires %d)inistrati.e Ti)e0 )roper #aintenance of a network re6uires

considerale ti#e and e,pertise0 Man$ schools have installed a network/ onl$ to

find that the$ did not udget for the necessar$ ad#inistrative support0

• ,ile "er.er (a ,ail0 Although a file server is no #ore susceptile to failure than

an$ other co#puter/ when the files server 3goes down/3 the entire network #a$co#e to a halt0 When this happens/ the entire school #a$ lose access to necessar$

 progra#s and files0

• Cables (a reak 0 !he !opolog$ chapter presents infor#ation aout the various

configurations of cales0 So#e of the configurations are designed to #ini#i4e the

inconvenience of a roken cale7 with other configurations/ one roken cale canstop the entire network0

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What is a Protocol? 

A protocol is a set of rules that governs the co##unications etween co#puters on a

network0 !hese rules include guidelines that regulate the following characteristics of a

network1 access #ethod/ allowed ph$sical topologies/ t$pes of caling/ and speed of datatransfer0

See the !opolog$ and %aling sections of this tutorial for #ore infor#ation0

!he #ost co##on protocols are1

• Ethernet 

• Local!alk  

• !oken "ing 

• FDDI 

• A!M 

Ethernet 

!he Ethernet protocol is $ far the #ost widel$ used0 Ethernet uses an access #ethod

called %SMA&%D *%arrier Sense Multiple Access&%ollision Detection+0 !his is a s$ste#where each co#puter listens to the cale efore sending an$thing through the network0 If

the network is clear/ the co#puter will trans#it0 If so#e other node is alread$

trans#itting on the cale/ the co#puter will wait and tr$ again when the line is clear0

So#eti#es/ two co#puters atte#pt to trans#it at the sa#e instant0 When this happens acollision occurs0 Each co#puter then acks off and waits a rando# a#ount of ti#e efore

atte#pting to retrans#it0 With this access #ethod/ it is nor#al to have collisions02owever/ the dela$ caused $ collisions and retrans#itting is ver$ s#all and does not

nor#all$ effect the speed of trans#ission on the network0

!he Ethernet protocol allows for linear us/ star/ or tree topologies0 Data can etrans#itted over wireless access points/ twisted pair/ coa,ial/ or fier optic cale at a

speed of 89 Mps up to 8999 Mps0

,ast +thernet

!o allow for an increased speed of trans#ission/ the Ethernet protocol has developed a

new standard that supports 899 Mps0 !his is co##onl$ called Fast Ethernet0 FastEthernet re6uires the use of different/ #ore e,pensive network concentrators&hus and

network interface cards0 In addition/ categor$ : twisted pair or fier optic cale isnecessar$0 Fast Ethernet is eco#ing co##on in schools that have een recentl$ wired0

$igabit +thernet

!he #ost recent develop#ent in the Ethernet standard is a protocol that has a

trans#ission speed of 8 Gps0 Gigait Ethernet is pri#aril$ used for ackones on a

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network at this ti#e0 In the future/ it will proal$ e used for workstation and server

connections also0 It can e used with oth fier optic caling and copper0 !he

8999'ase!;/ the copper cale used for Gigait Ethernet/ is e,pected to eco#e thefor#al standard in 8<<<0

LocalTalk Local!alk is a network protocol that was developed $ Apple %o#puter/ Inc0 for

Macintosh co#puters0 !he #ethod used $ Local!alk is called %SMA&%A *%arrier SenseMultiple Access with %ollision Avoidance+0 It is si#ilar to %SMA&%D e,cept that a

co#puter signals its intent to trans#it efore it actuall$ does so0 Local!alk adapters and

special twisted pair cale can e used to connect a series of co#puters through the serial port0 !he Macintosh operating s$ste# allows the estalish#ent of a peer.to.peer network

without the need for additional software0 With the addition of the server version of

AppleShare software/ a client&server network can e estalished0

!he Local!alk protocol allows for linear us/ star/ or tree topologies using twisted pair

cale0 A pri#ar$ disadvantage of Local!alk is speed0 Its speed of trans#ission is onl$

=>9 ?ps0

Token Ring 

!he !oken "ing protocol was developed $ I'M in the #id.8<@9s0 !he access #ethod

used involves token.passing0 In !oken "ing/ the co#puters are connected so that the

signal travels around the network fro# one co#puter to another in a logical ring0 A singleelectronic token #oves around the ring fro# one co#puter to the ne,t0 If a co#puter does

not have infor#ation to trans#it/ it si#pl$ passes the token on to the ne,t workstation0 If

a co#puter wishes to trans#it and receives an e#pt$ token/ it attaches data to the token0!he token then proceeds around the ring until it co#es to the co#puter for which the data

is #eant0 At this point/ the data is captured $ the receiving co#puter0 !he !oken "ing protocol re6uires a star.wired ring using twisted pair or fier optic cale0 It can operate at

trans#ission speeds of Mps or 8B Mps0 Due to the increasing popularit$ of Ethernet/the use of !oken "ing in school environ#ents has decreased0

FDDI 

Fier Distriuted Data Interface *FDDI+ is a network protocol that is used pri#aril$ to

interconnect two or #ore local area networks/ often over large distances0 !he access#ethod used $ FDDI involves token.passing0 FDDI uses a dual ring ph$sical topolog$0

!rans#ission nor#all$ occurs on one of the rings7 however/ if a reak occurs/ the s$ste#

keeps infor#ation #oving $ auto#aticall$ using portions of the second ring to create a

new co#plete ring0 A #a5or advantage of FDDI is speed0 It operates over fier opticcale at 899 Mps0

 AT 

As$nchronous !ransfer Mode *A!M+ is a network protocol that trans#its data at a speedof 8:: Mps and higher0 A!M works $ trans#itting all data in s#all packets of a fi,ed

si4e7 whereas/ other protocols transfer variale length packets0 A!M supports a variet$ of

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#edia such as video/ %D.6ualit$ audio/ and i#aging0 A!M e#plo$s a star topolog$/

which can work with fier optic as well as twisted pair cale0

A!M is #ost often used to interconnect two or #ore local area networks0 It is also

fre6uentl$ used $ Internet Service )roviders to utili4e high.speed access to the Internet

for their clients0 As A!M technolog$ eco#es #ore cost.effective/ it will provide another 

solution for constructing faster local area networks0

Protocol "&))ar

Protocol Cable "peed Topolog

+thernet !wisted )air/ %oa,ial/ Fier 89 Mps Linear 'us/ Star/ !ree

,ast +thernet !wisted )air/ Fier 899 Mps Star  

ocalTalk  !wisted )air 0=> Mps Linear 'us or Star  

Token *ing !wisted )air Mps . 8B Mps Star.Wired "ing

,/ Fier 899 Mps Dual ring

%T( !wisted )air/ Fier 8::.=@@ Mps Linear 'us/ Star/ !ree

What is Networking !ardware? 

 Networking hardware includes all co#puters/ peripherals/ interface cards and othere6uip#ent needed to perfor# data.processing and co##unications within the network0

%LI%? on the ter#s elow to learn #ore aout those pieces of networking hardware0

!his section provides infor#ation on the following co#ponents1

• File Servers 

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• Workstations 

•  Network Interface %ards 

• Switches 

• "epeaters 

• 'ridges 

• "outers 

File Servers

A file server stands at the heart of #ost networks0 It is a ver$ fast co#puter with a large

a#ount of "AM and storage space/ along with a fast network interface card0 !he network 

operating s$ste# software resides on this co#puter/ along with an$ software applicationsand data files that need to e shared0

!he file server controls the co##unication of infor#ation etween the nodes on a

network0 For e,a#ple/ it #a$ e asked to send a word processor progra# to oneworkstation/ receive a dataase file fro# another workstation/ and store an e.#ail

#essage during the sa#e ti#e period0 !his re6uires a co#puter that can store a lot of

infor#ation and share it ver$ 6uickl$0 File servers should have at least the followingcharacteristics1

• @99 #egahert4 or faster #icroprocessor *)entiu# > or / G or G:+

• A fast hard drive with at least 8=9 giga$tes of storage

• A "AID *"edundant Arra$ of Ine,pensive Disks+ to preserve data after a disk

casualt$

•A tape ack.up unit *i0e0 DA!/ CA/ ip/ or %D."W drive+

•  Nu#erous e,pansion slots

• Fast network interface card

• At least of :8= M' of "AM

Workstations

All of the user co#puters connected to a network are called workstations0 A t$pical

workstation is a co#puter that is configured with a network interface card/ networking

software/ and the appropriate cales0 Workstations do not necessaril$ need flopp$ disk

drives ecause files can e saved on the file server0 Al#ost an$ co#puter can serve as anetwork workstation0

Network Interface "ards

!he network interface card *NI%+ provides the ph$sical connection etween the networkand the co#puter workstation0 Most NI%s are internal/ with the card fitting into an

e,pansion slot inside the co#puter0 So#e co#puters/ such as Mac %lassics/ use e,ternal

 o,es which are attached to a serial port or a S%SI port0 Laptop co#puters can now e

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 purchased with a network interface card uilt.in or with network cards that slip into a

)%M%IA slot0

 Network interface cards are a #a5or factor in deter#ining the speed and perfor#ance of a

network0 It is a good idea to use the fastest network card availale for the t$pe of

workstation $ou are using0

!he three #ost co##on network interface connections are Ethernet cards/ Local!alk

connectors/ and !oken "ing cards0 According to a International Data %orporation stud$/

Ethernet is the #ost popular/ followed $ !oken "ing and Local!alk *SantAngelo/ "0*8<<:+0 NetWare Unleashed / Indianapolis/ IN1 Sa#s )ulishing+0

+thernet Cards

Ethernet cards are usuall$ purchased separatel$ fro# a co#puter/ although #an$

co#puters *such as the Macintosh+ now include an option for a pre.installed Ethernetcard0 Ethernet cards contain connections for either coa,ial or twisted pair cales *or oth+

*See fig0 8+0 If it is designed for coa,ial cale/ the connection will e 'N%0 If it is

designed for twisted pair/ it will have a "C.: connection0 So#e Ethernet cards also

contain an A(I connector0 !his can e used to attach coa,ial/ twisted pair/ or fier opticscale to an Ethernet card0 When this #ethod is used there is alwa$s an e,ternal

transceiver attached to the workstation0 *See the %aling section for #ore infor#ation on

connectors0+

Fig0 80 Ethernet card0

Fro# top to otto#1"C.:/ A(I/ and 'N% connectors

ocalTalk Connectors

Local!alk is Apples uilt.in solution for networking Macintosh co#puters0 It utili4es aspecial adapter o, and a cale that plugs into the printer port of a Macintosh *See fig0 =+0

A #a5or disadvantage of Local!alk is that it is slow in co#parison to Ethernet0 Most

Ethernet connections operate at 89 Mps *Megaits per second+0 In contrast/ Local!alkoperates at onl$ =>9 ?ps *or 0=> Mps+0

Fig0=0 Local!alk connectors

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+thernet Cards .s ocalTalk Connections

+thernet  ocalTalk  

Fast data transfer *89 to

899 Mps+

Slow data transfer *0=>

Mps+

E,pensive . purchasedseparatel$ 'uilt into Macintoshco#puters

"e6uires co#puter slot No co#puter slot

necessar$

Availale for #ost

co#puters

Works onl$ on Macintosh

co#puters

Token *ing Cards

!oken "ing network cards look si#ilar to Ethernet cards0 -ne visile difference is thet$pe of connector on the ack end of the card0 !oken "ing cards generall$ have a nine pin

DIN t$pe connector to attach the card to the network cale0

Switch

A concentrator is a device that provides a central connection point for cales fro#workstations/ servers/ and peripherals0 In a star topolog$/ twisted.pair wire is run fro#

each workstation to a central switch&hu0 Most switches are active/ that is the$

electricall$ a#plif$ the signal as it #oves fro# one device to another0 Switches no longer  roadcast network packets as hus did in the past/ the$ #e#ori4e addressing of

co#puters and send the infor#ation to the correct location directl$0 Switches are1

• (suall$ configured with @/ 8=/ or = "C.: ports

• -ften used in a star or star.wired ring topolog$

• Sold with speciali4ed software for port #anage#ent

• Also called hus

• (suall$ installed in a standardi4ed #etal rack that also #a$ store net#ode#s/ 

 ridges/ or routers 

Re#eaters

Since a signal loses strength as it passes along a cale/ it is often necessar$ to oost the

signal with a device called a repeater0 !he repeater electricall$ a#plifies the signal itreceives and reroadcasts it0 "epeaters can e separate devices or the$ can e

incorporated into a concentrator0 !he$ are used when the total length of $our networkcale e,ceeds the standards set for the t$pe of cale eing used0

A good e,a#ple of the use of repeaters would e in a local area network using a star

topolog$ with unshielded twisted.pair caling0 !he length li#it for unshielded twisted.

 pair cale is 899 #eters0 !he #ost co##on configuration is for each workstation to econnected $ twisted.pair cale to a #ulti.port active concentrator0 !he concentrator

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a#plifies all the signals that pass through it allowing for the total length of cale on the

network to e,ceed the 899 #eter li#it0

$ridges

A ridge is a device that allows $ou to seg#ent a large network into two s#aller/ #ore

efficient networks0 If $ou are adding to an older wiring sche#e and want the newnetwork to e up.to.date/ a ridge can connect the two0

A ridge #onitors the infor#ation traffic on oth sides of the network so that it can pass

 packets of infor#ation to the correct location0 Most ridges can 3listen3 to the network

and auto#aticall$ figure out the address of each co#puter on oth sides of the ridge0

!he ridge can inspect each #essage and/ if necessar$/ roadcast it on the other side ofthe network0

!he ridge #anages the traffic to #aintain opti#u# perfor#ance on oth sides of thenetwork0 ou #ight sa$ that the ridge is like a traffic cop at a us$ intersection during

rush hour0 It keeps infor#ation flowing on oth sides of the network/ ut it does not allow

unnecessar$ traffic through0 'ridges can e used to connect different t$pes of caling/ or ph$sical topologies0 !he$ #ust/ however/ e used etween networks with the sa#e protocol0

Ro%ters

A router translates infor#ation fro# one network to another7 it is si#ilar to a

superintelligent ridge0 "outers select the est path to route a #essage/ ased on the

destination address and origin0 !he router can direct traffic to prevent head.on collisions/and is s#art enough to know when to direct traffic along ack roads and shortcuts0

While ridges know the addresses of all co#puters on each side of the network/ routersknow the addresses of co#puters/ ridges/ and other routers on the network0 "outers caneven 3listen3 to the entire network to deter#ine which sections are usiest .. the$ can

then redirect data around those sections until the$ clear up0

If $ou have a school LAN that $ou want to connect to the Internet/ $ou will need to purchase a router0 In this case/ the router serves as the translator etween the infor#ation

on $our LAN and the Internet0 It also deter#ines the est route to send the data over the

Internet0 "outers can1

• Direct signal traffic efficientl$

• "oute #essages etween an$ two protocols

• "oute #essages etween linear us/ star / and star.wired ring topologies

• "oute #essages across fier optic/ coa,ial/ and twisted.pair  caling

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What is Network "a&ling? 

%ale is the #ediu# through which infor#ation usuall$ #oves fro# one network deviceto another0 !here are several t$pes of cale which are co##onl$ used with LANs0 In

so#e cases/ a network will utili4e onl$ one t$pe of cale/ other networks will use avariet$ of cale t$pes0 !he t$pe of cale chosen for a network is related to the networks

topolog$/ protocol/ and si4e0 (nderstanding the characteristics of different t$pes of caleand how the$ relate to other aspects of a network is necessar$ for the develop#ent of a

successful network0

!he following sections discuss the t$pes of cales used in networks and other relatedtopics0

• (nshielded !wisted )air *(!)+ %ale 

• Shielded !wisted )air *S!)+ %ale 

•%oa,ial %ale 

• Fier -ptic %ale 

• Wireless LANs 

• %ale Installation Guides 

'nshielded Twisted Pair ('TP) "a&le

!wisted pair caling co#es in two varieties1 shielded and unshielded0 (nshielded twisted

 pair *(!)+ is the #ost popular and is generall$ the est option for school networks *Seefig0 8+0

Fig080 (nshielded twisted pair

!he 6ualit$ of (!) #a$ var$ fro# telephone.grade wire to e,tre#el$ high.speed cale0

!he cale has four pairs of wires inside the 5acket0 Each pair is twisted with a different

nu#er of twists per inch to help eli#inate interference fro# ad5acent pairs and otherelectrical devices0 !he tighter the twisting/ the higher the supported trans#ission rate and

the greater the cost per foot0 !he EIA&!IA *Electronic Industr$

Association&!eleco##unication Industr$ Association+ has estalished standards of (!)and rated five categories of wire0

Categories o# nshielded Twisted Pair

Tpe se

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%ategor$ 8 oice -nl$ *!elephone Wire+

%ategor$ = Data to Mps *Local!alk+

%ategor$ > Data to 89 Mps *Ethernet+

%ategor$ Data to =9 Mps *8B Mps !oken "ing+

%ategor$ : Data to 899 Mps *Fast Ethernet+

'u$ the est cale $ou can afford7 #ost schools purchase %ategor$ > or %ategor$ :0 If$ou are designing a 89 Mps Ethernet network and are considering the cost savings of

 u$ing %ategor$ > wire instead of %ategor$ :/ re#e#er that the %ategor$ : cale will

 provide #ore 3roo# to grow3 as trans#ission technologies increase0 'oth %ategor$ > and%ategor$ : (!) have a #a,i#u# seg#ent length of 899 #eters0 In Florida/ %ategor$ :

cale is re6uired for retrofit grants0 89'ase! refers to the specifications for unshielded

twisted pair cale *%ategor$ >/ / or :+ carr$ing Ethernet signals0 %ategor$ B is relativel$new and is used for gigait connections0

nshielded Twisted Pair Connector!he standard connector for unshielded twisted pair caling is an "C.: connector0 !his is

a plastic connector that looks like a large telephone.st$le connector *See fig0 =+0 A slotallows the "C.: to e inserted onl$ one wa$0 "C stands for "egistered Cack/ i#pl$ing

that the connector follows a standard orrowed fro# the telephone industr$0 !his standard

designates which wire goes with each pin inside the connector0

Fig0 =0 "C.: connector

Shielded Twisted Pair (STP) "a&le

A disadvantage of (!) is that it #a$ e susceptile to radio and electrical fre6uenc$interference0 Shielded twisted pair *S!)+ is suitale for environ#ents with electrical

interference7 however/ the e,tra shielding can #ake the cales 6uite ulk$0 Shielded

twisted pair is often used on networks using !oken "ing topolog$0

"oa*ial "a&le

%oa,ial caling has a single copper conductor at its center0 A plastic la$er provides

insulation etween the center conductor and a raided #etal shield *See fig0 >+0 !he #etal

shield helps to lock an$ outside interference fro# fluorescent lights/ #otors/ and otherco#puters0

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Fig0 >0 %oa,ial cale

Although coa,ial caling is difficult to install/ it is highl$ resistant to signal interference0In addition/ it can support greater cale lengths etween network devices than twisted

 pair cale0 !he two t$pes of coa,ial caling are thick coa,ial and thin coa,ial0

!hin coa,ial cale is also referred to as thinnet0 89'ase= refers to the specifications forthin coa,ial cale carr$ing Ethernet signals0 !he = refers to the appro,i#ate #a,i#u#

seg#ent length eing =99 #eters0 In actual fact the #a,i#u# seg#ent length is 8@:

#eters0 !hin coa,ial cale is popular in school networks/ especiall$ linear us networks0

!hick coa,ial cale is also referred to as thicknet0 89'ase: refers to the specifications for

thick coa,ial cale carr$ing Ethernet signals0 !he : refers to the #a,i#u# seg#ent

length eing :99 #eters0 !hick coa,ial cale has an e,tra protective plastic cover thathelps keep #oisture awa$ fro# the center conductor0 !his #akes thick coa,ial a great

choice when running longer lengths in a linear us network0 -ne disadvantage of thickcoa,ial is that it does not end easil$ and is difficult to install0

Coa-ial Cable Connectors

!he #ost co##on t$pe of connector used with coa,ial cales is the 'a$one.Neill.

%oncel#an *'N%+ connector *See fig0 +0 Different t$pes of adapters are availale for

'N% connectors/ including a !.connector/ arrel connector/ and ter#inator0 %onnectorson the cale are the weakest points in an$ network0 !o help avoid prole#s with $our

network/ alwa$s use the 'N% connectors that cri#p/ rather than screw/ onto the cale0

Fig0 0 'N% connector

Fi&er +#tic "a&le

Fier optic caling consists of a center glass core surrounded $ several la$ers of

 protective #aterials *See fig0 :+0 It trans#its light rather than electronic signals

eli#inating the prole# of electrical interference0 !his #akes it ideal for certainenviron#ents that contain a large a#ount of electrical interference0 It has also #ade it the

standard for connecting networks etween uildings/ due to its i##unit$ to the effects of#oisture and lighting0

Fier optic cale has the ailit$ to trans#it signals over #uch longer distances than

coa,ial and twisted pair0 It also has the capailit$ to carr$ infor#ation at vastl$ greater

speeds0 !his capacit$ roadens co##unication possiilities to include services such asvideo conferencing and interactive services0 !he cost of fier optic caling is co#parale

to copper caling7 however/ it is #ore difficult to install and #odif$0 89'aseF refers to

the specifications for fier optic cale carr$ing Ethernet signals0

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Fig0:0 Fier optic cale

Facts aout fier optic cales1

• -uter insulating 5acket is #ade of !eflon or )%0

• ?evlar fier helps to strengthen the cale and prevent reakage0

• A plastic coating is used to cushion the fier center0

• %enter *core+ is #ade of glass or plastic fiers0

,iber 6ptic Connector

!he #ost co##on connector used with fier optic cale is an S! connector0 It is arrelshaped/ si#ilar to a 'N% connector0 A newer connector/ the S%/ is eco#ing #ore

 popular0 It has a s6uared face and is easier to connect in a confined space0

+thernet Cable "&))ar

"peci#ication Cable Tpe (a-i)&) length

17aseT (nshielded !wisted )air 899 #eters

17ase2 !hin %oa,ial 8@: #eters

17ase5 !hick %oa,ial :99 #eters

17ase, Fier -ptic =999 #eters

177aseT (nshielded !wisted )air 899 #eters

177aseT8 (nshielded !wisted )air ==9 #eters

Wireless LANs

 Not all networks are connected with caling7 so#e networks are wireless0 Wireless LANs

use high fre6uenc$ radio signals/ infrared light ea#s/ or lasers to co##unicate etweenthe workstations and the file server or hus0 Each workstation and file server on a

wireless network has so#e sort of transceiver&antenna to send and receive the data0Infor#ation is rela$ed etween transceivers as if the$ were ph$sicall$ connected0 For

longer distance/ wireless co##unications can also take place through cellular telephone

technolog$/ #icrowave trans#ission/ or $ satellite0

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Wireless networks are great for allowing laptop co#puters or re#ote co#puters to

connect to the LAN0 Wireless networks are also eneficial in older uildings where it

#a$ e difficult or i#possile to install cales0

!he two #ost co##on t$pes of infrared co##unications used in schools are line.of.sight

and scattered roadcast0 Line.of.sight co##unication #eans that there #ust e an

unlocked direct line etween the workstation and the transceiver0 If a person walkswithin the line.of.sight while there is a trans#ission/ the infor#ation would need to e

sent again0 !his kind of ostruction can slow down the wireless network0

Scattered infrared co##unication is a roadcast of infrared trans#issions sent out in

#ultiple directions that ounces off walls and ceilings until it eventuall$ hits the receiver0

 Networking co##unications with laser are virtuall$ the sa#e as line.of.sight infrared

networks0

Wireless LANs have several disadvantages0 !he$ provide poor securit$/ and are

susceptile to interference fro# lights and electronic devices0 !he$ are also slower thanLANs using caling0

Installing "a&le , So-e .%idelines

When running cale/ it is est to follow a few si#ple rules1

• Alwa$s use #ore cale than $ou need0 Leave plent$ of slack0

• !est ever$ part of a network as $ou install it0 Even if it is rand new/ it #a$ have

 prole#s that will e difficult to isolate later0

• Sta$ at least > feet awa$ fro# fluorescent light o,es and other sources of

electrical interference0

• If it is necessar$ to run cale across the floor/ cover the cale with cale

 protectors0

• Lael oth ends of each cale0

• (se cale ties *not tape+ to keep cales in the sa#e location together0

What is a To#olog/? 

!he ph$sical topolog$ of a network refers to the configuration of cales/ co#puters/ and

other peripherals0 )h$sical topolog$ should not e confused with logical topolog$ whichis the #ethod used to pass infor#ation etween workstations0 Logical topolog$ was

discussed in the )rotocol chapter 0

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ain T/#es of Ph/sical To#ologies

!he following sections discuss the ph$sical topologies used in networks and other relatedtopics0

• Linear 'us 

• Star  

• Star.Wired "ing 

• !ree 

• %onsiderations When %hoosing a !opolog$ 

• Su##ar$ %hart 

Linear $%s

A linear us topolog$ consists of a #ain run of cale with a ter#inator  at each end *See

fig0 8+0 All nodes *file server/ workstations/ and peripherals+ are connected to the linearcale0 Ethernet and Local!alk  networks use a linear us topolog$0

Fig0 80 Linear 'us topolog$

%d.antages o# a inear &s Topolog

• Eas$ to connect a co#puter or peripheral to a linear us0

• "e6uires less cale length than a star topolog$0

isad.antages o# a inear &s Topolog

• Entire network shuts down if there is a reak in the #ain cale0

• !er#inators are re6uired at oth ends of the ackone cale0

• Difficult to identif$ the prole# if the entire network shuts down0

•  Not #eant to e used as a stand.alone solution in a large uilding0

Star

A star topolog$ is designed with each node *file server/ workstations/ and peripherals+

connected directl$ to a central network hu or concentrator  *See fig0 =+0

Data on a star network passes through the hu or concentrator efore continuing to its

destination0 !he hu or concentrator #anages and controls all functions of the network0 It

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also acts as a repeater  for the data flow0 !his configuration is co##on with twisted pair

cale7 however/ it can also e used with coa,ial cale or fier optic cale0

Fig0 =0 Star topolog$

%d.antages o# a "tar Topolog

• Eas$ to install and wire0

•  No disruptions to the network then connecting or re#oving devices0

• Eas$ to detect faults and to re#ove parts0

isad.antages o# a "tar Topolog

• "e6uires #ore cale length than a linear topolog$0

• If the hu or concentrator fails/ nodes attached are disaled0

• More e,pensive than linear us topologies ecause of the cost of the

concentrators0

!he protocols used with star configurations are usuall$ Ethernet or Local!alk 0 !oken"ing uses a si#ilar topolog$/ called the star.wired ring0

Star,Wired Ring 

A star.wired ring topolog$ #a$ appear *e,ternall$+ to e the sa#e as a star topolog$0

Internall$/ the MA( *#ultistation access unit+ of a star.wired ring contains wiring that

allows infor#ation to pass fro# one device to another in a circle or ring *See fig0 >+0 !he!oken "ing protocol uses a star.wired ring topolog$0

Tree

A tree topolog$ co#ines characteristics of linear us and star topologies0 It consists ofgroups of star.configured workstations connected to a linear us ackone cale *See fig0

+0 !ree topologies allow for the e,pansion of an e,isting network/ and enale schools to

configure a network to #eet their needs0

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Fig0 0 !ree topolog$

%d.antages o# a Tree Topolog

• )oint.to.point wiring for individual seg#ents0

• Supported $ several hardware and software venders0

isad.antages o# a Tree Topolog

• -verall length of each seg#ent is li#ited $ the t$pe of caling used0

• If the ackone line reaks/ the entire seg#ent goes down0

• More difficult to configure and wire than other topologies0

59493 *&le

A consideration in setting up a tree topolog$ using Ethernet protocol is the :..> rule0-ne aspect of the Ethernet protocol re6uires that a signal sent out on the network cale

reach ever$ part of the network within a specified length of ti#e0 Each concentrator or

repeater that a signal goes through adds a s#all a#ount of ti#e0 !his leads to the rule that etween an$ two nodes on the network there can onl$ e a #a,i#u# of : seg#ents/

connected through repeaters&concentrators0 In addition/ onl$ > of the seg#ents #a$ e populated *trunk+ seg#ents if the$ are #ade of coa,ial cale0 A populated seg#ent is onewhich has one or #ore nodes attached to it 0 In Figure / the :..> rule is adhered to0 !he

furthest two nodes on the network have seg#ents and > repeaters&concentrators

 etween the#0

!his rule does not appl$ to other network protocols or Ethernet networks where all fier

optic caling or a co#ination of a fier ackone with (!) caling is used0 If there is a

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co#ination of fier optic ackone and (!) caling/ the rule is si#pl$ translated to H.

B.: rule0

"onsiderations When "hoosing a To#olog/0

• (one0 A linear us network #a$ e the least e,pensive wa$ to install a network7

$ou do not have to purchase concentrators0

• ength o# cable needed0 !he linear us network uses shorter lengths of cale0

• ,&t&re growth0 With a star topolog$/ e,panding a network is easil$ done $

adding another concentrator0

• Cable tpe0 !he #ost co##on cale in schools is unshielded twisted pair/ which

is #ost often used with star topologies0

S%--ar/ "hart0

Phsical Topolog Co))on Cable Co))on Protocol

inear &s

!wisted )air %oa,ial

Fier 

Ethernet

Local!alk 

"tar!wisted )air Fier 

EthernetLocal!alk 

"tar9Wired *ing !wisted )air !oken "ing

Tree

!wisted )air 

%oa,ialFier 

Ethernet

What is a Network +#erating S/ste-? 

(nlike operating s$ste#s/ such as D-S and Windows/ that are designed for single users

to control one co#puter/ network operating s$ste#s *N-S+ coordinate the activities of

#ultiple co#puters across a network0 !he network operating s$ste# acts as a director tokeep the network running s#oothl$0

!he two #a5or t$pes of network operating s$ste#s are1

• )eer.to.)eer  

• %lient&Server  

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Peer,to,Peer 

)eer.to.peer network operating s$ste#s allow users to share resources and files locatedon their co#puters and to access shared resources found on other co#puters0 2owever/

the$ do not have a file server or a centrali4ed #anage#ent source *See fig0 8+0 In a peer.

to.peer network/ all co#puters are considered e6ual7 the$ all have the sa#e ailities to

use the resources availale on the network0 )eer.to.peer networks are designed pri#aril$for s#all to #ediu# local area networks0 AppleShare and Windows for Workgroups are

e,a#ples of progra#s that can function as peer.to.peer network operating s$ste#s0

Fig0 80 )eer.to.peer network

%d.antages o# a peer9to9peer network:

• Less initial e,pense . No need for a dedicated server0

• Setup . An operating s$ste# *such as Windows ;)+ alread$ in place #a$ onl$

need to e reconfigured for peer.to.peer operations0

isad.antages o# a peer9to9peer network:

• Decentrali4ed . No central repositor$ for files and applications0

• Securit$ . Does not provide the securit$ availale on a client&server network0

"lient1Server 

%lient&server network operating s$ste#s allow the network to centrali4e functions and

applications in one or #ore dedicated file servers *See fig0 =+0 !he file servers eco#e the

heart of the s$ste#/ providing access to resources and providing securit$0 Individualworkstations *clients+ have access to the resources availale on the file servers0 !he

network operating s$ste# provides the #echanis# to integrate all the co#ponents of the

network and allow #ultiple users to si#ultaneousl$ share the sa#e resources irrespective

of ph$sical location0 Novell Netware and Windows =999 Server are e,a#ples ofclient&server network operating s$ste#s0

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Fig0 =0 %lient&server network

%d.antages o# a clientser.er network:

• %entrali4ed . "esources and data securit$ are controlled through the server0

• Scalailit$ . An$ or all ele#ents can e replaced individuall$ as needs increase0

• Fle,iilit$ . New technolog$ can e easil$ integrated into s$ste#0

• Interoperailit$ . All co#ponents *client&network&server+ work together0

• Accessiilit$ . Server can e accessed re#otel$ and across #ultiple platfor#s0

isad.antages o# a clientser.er network:

• E,pense . "e6uires initial invest#ent in dedicated server0

• Maintenance . Large networks will re6uire a staff to ensure efficient operation0

• Dependence . When server goes down/ operations will cease across the network0

E*a-#les of network o#erating s/ste-s

!he following list includes so#e of the #ore popular peer.to.peer and client&servernetwork operating s$ste#s0

• AppleShare 

• Microsoft Windows Server  

•  Novell Netware 

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17ase2 . Ethernet specification for thin coa,ial cale/ trans#its signals at 89 Mps

*#egaits per second+ with a distance li#it of 8@: #eters per seg#ent0

17ase5 . Ethernet specification for thick coa,ial cale/ trans#its signals at 89 Mps

*#egaits per second+ with a distance li#it of :99 #eters per seg#ent0

17ase, . Ethernet specification for fier optic cale/ trans#its signals at 89 Mps*#egaits per second+ with a distance li#it of =999 #eters per seg#ent0

17aseT . Ethernet specification for unshielded twisted pair cale *categor$ >/ / or :+/

trans#its signals at 89 Mps *#egaits per second+ with a distance li#it of 899 #eters per seg#ent0

177aseT . Ethernet specification for unshielded twisted pair caling that is used to

trans#it data at 899 Mps *#egaits per second+ with a distance li#it of 899 #eters perseg#ent0

1777aseT8 .Ethernet specification for unshielded twisted pair caling that is used totras#it data at 8 Gps *gigaits per second+ with a distance li#itation of ==9 #eters per

seg#ent0

%snchrono&s Trans#er (ode ;%T(< . A network protocol that trans#its data at aspeed of 8:: Mps and higher0 It is #ost often used to interconnect two or #ore local

area networks0

%ppleTalk  . Apple %o#puters network protocol originall$ designed to run overLocal!alk networks/ ut can also run on Ethernet and !oken "ing0

%/ Connector *Attach#ent (nit Interface+ . A 8: pin connector found on Ethernet

cards that can e used for attaching coa,ial/ fier optic/ or twisted pair cale0

ackbone . A cale to which #ultiple nodes or workstations are attached0

it . 'inar$ digit in the inar$ nu#ering s$ste#0 Its value can e 9 or 80 In an @.it

character sche#e/ it takes @ its to #ake a $te *character+ of data0

NC Connector *'a$one.Neill.%oncel#an+ . Standard connector used to connect

89'ase= coa,ial cale0

ridge . Devices that connect and pass packets etween two network seg#ents that use

the sa#e co##unications protocol0

Cable . !rans#ission #ediu# of copper wire or optical fier wrapped in a protective

cover0

Client"er.er . A networking s$ste# in which one or #ore file servers *Server+ provideservices7 such as network #anage#ent/ application and centrali4ed data storage for

workstations *%lients+0

C"(%C% . %arrier Sense Multiple Access %ollision Avoidance is a network access#ethod in which each device signals its intent to trans#it efore it actuall$ does so0 !his

 prevents other devices fro# sending infor#ation/ thus preventing collisions fro#

occurring etween signals fro# two or #ore devices0 !his is the access #ethod used $Local!alk0

C"(%C . %arrier Sense Multiple Access %ollision Detection is a network access

#ethod in which devices that are read$ to trans#it data first check the channel for a

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carrier0 If no carrier is sensed/ a device can trans#it0 If two devices trans#it at once/ a

collision occurs and each co#puter acks off and waits a rando# a#ount of ti#e efore

atte#pting to retrans#it0 !his is the access #ethod used $ Ethernet0

Coa-ial Cable . %ale consisting of a single copper conductor in the center surrounded

 $ a plastic la$er for insulation and a raided #etal outer shield0

Concentrator . A device that provides a central connection point for cales fro#

workstations/ servers/ and peripherals0 Most concentrators contain the ailit$ to a#plif$

the electrical signal the$ receive0

/N . A plug and socket connector consisting of a circular pattern of pins in a #etal

sleeve0 !his t$pe of connector is co##onl$ seen on ke$oards0

&)b Ter)inal . "efers to devices that are designed to co##unicate e,clusivel$ with ahost *#ain fra#e+ co#puter0 It receives all screen la$outs fro# the host co#puter and

sends all ke$oard entr$ to the host0 It cannot function without the host co#puter0

+9)ail . An electronic #ail #essage sent fro# a host co#puter to a re#ote co#puter0

+nd ser . "efers to the hu#an e,ecuting applications on the workstation0+thernet . A network protocol invented $ ;ero, %orporation and developed 5ointl$ $;ero,/ Intel and Digital E6uip#ent %orporation0 Ethernet networks use %SMA&%D and

run over a variet$ of cale t$pes at 89 Mps *#egaits per second+0

+-pansion "lot . Area in a co#puter that accepts additional input&output oards to

increase the capailit$ of the co#puter0

,ast +thernet . A new Ethernet standard that supports 899 Mps using categor$ :twisted pair or fier optic cale0

,iber istrib&ted ata /nter#ace ;,/< . A network protocol that is used pri#aril$ to

interconnect two or #ore local area networks/ often over large distances0

,iber 6ptic Cable . A cale/ consisting of a center glass core surrounded $ la$ers of

 plastic/ that trans#its data using light rather than electricit$0 It has the ailit$ to carr$

#ore infor#ation over #uch longer distances0

,ile "er.er . A co#puter connected to the network that contains pri#ar$

files&applications and shares the# as re6uested with the other co#puters on the network0

If the file server is dedicated for that purpose onl$/ it is connected to a client&servernetwork0 An e,a#ple of a client&server network is Novell Netware0 All the co#puters

connected to a peer.to.peer network are capale of eing the file server0 !wo e,a#ples of 

 peer.to.peer networks are LANtastic and Windows for Workgroups0

$igabit +thernet . An Ethernet protocol that raises the trans#ission rates to 8 Gps

*gigaits per second+0 It is pri#aril$ used for a high speed ackone of a network0

$igabte *G'+ . -ne illion $tes of infor#ation0 -ne thousand #ega$tes0

H&b . A hardware device that contains #ultiple independent ut connected #odules of

network and internetwork e6uip#ent0 2us can e active *where the$ repeat signals sentthrough the#+ or passive *where the$ do not repeat ut #erel$ split signals sent through

the#+0

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/n#rared . Electro#agnetic waves whose fre6uenc$ range is aove that of #icrowaves/

 ut elow that of the visile spectru#0

/ntranet . Network internal to an organi4ation that uses Internet protocols0

/nternet . A gloal network of networks used to e,change infor#ation using the !%)&I)

 protocol0 It allows for electronic #ail and the accessing ad retrieval of infor#ation fro#re#ote sources0

%N *Local Area Network+ . A network connecting co#puters in a relativel$ s#all area

such as a uilding0

inear &s . A network topolog$ in which each node attaches directl$ to a co##on

cale0

ocalTalk  . Apple %orporation proprietar$ protocol that uses %SMA&%A #edia access

sche#e and supports trans#issions at speeds of =>9 ?ps *?iloits per second+0

(%N *Metropolitan Area Network+ . A network connecting co#puters over a largegeographical area/ such as a cit$ or school district0

(% *Multistation Access (nit+ . A !oken "ing wiring hu0

(ode) *Modulator&De#odulator+ . Devices that convert digital and analog signals0

Mode#s allow co#puter data *digital+ to e trans#itted over voice.grade telephone lines

*analog+0

(&ltiple-er . A device that allows #ultiple logical signals to e trans#itted

si#ultaneousl$ across a single ph$sical channel0

Network (ode) . A #ode# connected to a Local Area Network *LAN+ that isaccessile fro# an$ workstation on the network0

Network /nter#ace Card *NI%+ . A oard that provides network co##unication

capailities to and fro# a co#puter0

Network 6perating "ste) *N-S+ . -perating s$ste# designed to pass infor#ation and

co##unicate etween #ore than one co#puter0 E,a#ples include AppleShare/ Novell NetWare/ and Windows N! Server0

Node . End point of a network connection0 Nodes include an$ device attached to a

network such as file servers/ printers/ or workstations0

Node e.ices . An$ co#puter or peripheral that is connected to the network0

PC(C/% . An e,pansion slot found in #an$ laptop co#puters0

Peer9to9Peer Network  . A network in which resources and files are shared without a

centrali4ed #anage#ent source0

Phsical Topolog . !he ph$sical la$out of the network7 how the cales are arranged7and how the co#puters are connected0

Point9to9Point . A direct link etween two o5ects in a network0

Ports . A connection point for a cale0

Protocol .A for#al description of a set of rules and conventions that govern how devices

on a network e,change infor#ation0

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*%/ *"edundant Arra$ of Ine,pensive Disks+ . A configuration of #ultiple disks

designed to preserve data after a disk casualt$0

*%( *"ando# Access Me#or$+ . !he working #e#or$ of a co#puter where data and

 progra#s are te#poraril$ stored0 "AM onl$ holds infor#ation when the co#puter is on0

*epeater . A device used in a network to strengthen a signal as it is passed along thenetwork cale0

*=945 . Standard connectors used for unshielded twisted.pair cale0

*o&ter .A device that routes infor#ation etween interconnected networks0 It can select

the est path to route a #essage/ as well as translate infor#ation fro# one network to

another0 It is si#ilar to a superintelligent ridge0

"C"/ ;")all Co)p&ter "erial /nter#ace< . An interface controller that allows several

 peripherals to e connected to the sa#e port on a co#puter0

"eg)ent . "efers to a section of cale on a network0 In Ethernet networks/ two t$pes ofseg#ents are defined0 A populated or trunk seg#ent is a network cale that has one or

#ore nodes attached to it0 A link seg#ent is a cale that connects a co#puter to aninterconnecting device/ such as a repeater or concentrator/ or connects a interconnectingdevice to another interconnecting device0

"neaker9Net . "efers to a #anual #ethod of sharing files in which a file is copied fro# a

co#puter to a flopp$ disk/ transported to a second co#puter $ a person ph$sicall$walking *apparentl$ wearing sneakers+ to the second co#puter/ and #anuall$ transferring

the file fro# flopp$ disk to the second co#puter0

"peed o# ata Trans#er . !he rate at which infor#ation travels through a network/usuall$ #easured in #egaits per second0

"tar Topolog . LAN topolog$ in which each node on a network is connected directl$ to

a central network hu or concentrator0"tar9Wired *ing . Network topolog$ that connects network devices *such as co#puters

and printers+ in a co#plete circle0

Tape ack9p . %op$ing all the data and progra#s of a co#puter s$ste# on #agnetic

tape0 -n tape/ data is stored se6uentiall$0 When retrieving data/ the tape is searched fro#

the eginning of tape until the data is found0

Ter)inator . A device that provides electrical resistance at the end of a trans#ission line0

Its function is to asor signals on the line/ there$ keeping the# fro# ouncing ack

and eing received again $ the network0

Thicknet . A thick coa,ial cale that is used with a 89'ase: Ethernet LAN0

Thinnet . A thin coa,ial cale that is used with a 89'ase= Ethernet LAN0

Token . A special packet that contains data and acts as a #essenger or carrier etween

each co#puter and device on a ring topolog$0 Each co#puter #ust wait for the

#essenger to stop at its node efore it can send data over the network0

Token *ing . A network protocol developed $ I'M in which co#puters access the

network through token.passing0 (suall$ uses a star.wired ring topolog$0

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Topolog . !here are two t$pes of topolog$1 ph$sical and logical0 !he ph$sical topolog$

of a network refers to the configuration of cales/ co#puters/ and other peripherals0

Logical topolog$ is the #ethod used to pass the infor#ation etween workstations0 Issuesinvolving logical topologies are discussed on the )rotocol chapter 

Transcei.er *!rans#itter&"eceiver+ . A Device that receives and sends signals over a

#ediu#0 In networks/ it is generall$ used to allow for the connection etween twodifferent t$pes of cale connectors/ such as A(I and "C.:0

Tree Topolog . LAN topolog$ si#ilar to linear us topolog$/ e,cept that tree networkscan contain ranches with #ultiple nodes0

Twisted Pair . Network caling that consists of four pairs of wires that are #anufactured

with the wires twisted to certain specifications0 Availale in shielded and unshieldedversions0

" ;ni.ersal "erial &s< Port . A hardware interface for low.speed peripherals such

as the ke$oard/ #ouse/ 5o$stick/ scanner/ printer/ and telephon$ devices0

W%N *Wide Area Network+ . A network connecting co#puters within ver$ large areas/

such as states/ countries/ and the world0

Workgro&p . A collection of workstations and servers on a LAN that are designated to

co##unicate and e,change data with one another0

Workstation . A co#puter connected to a network at which users interact with softwarestored on the network0

• Articles 

• 'ooks 

• World Wide We Sites 

 Articles

• Connecting the Networking ots

o

"o&rce: ED(%-M "eview7 v=@ n:/ p>B.8/ Sep.-ct 8<<>%&thor: "icart/ G0

o %bstract: )rovides technical reco##endations for wiring of college

ca#puses to provide for current and future co#puter network needs0

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• %N Ho> % $&ide to Networking Personal Co)p&ters

o "o&rce: School 'usiness Affairs7 v:< n89/ p>@.9 =.B/ -ct

8<<>%&thor: Dal$/ ?0 F0

o %bstract: )rovides e,a#ples of co##on ad#inistrative tasks in school

district offices that can e e,pedited using an ad#inistrative local areanetwork *LAN+0 E,plains how districts can develop a #aster plan for

installing a LAN0

• (&lti9Protocol %N esign and /)ple)entation: % Case "t&d

o "o&rce: !020E0 Cournal7 v== n</ p@9.@:/ Apr 8<<:%&thor: 2a4ari/ S0

o %bstract: "eports on the installation of a local area network *LAN+ at

East %arolina (niversit$0 !opics include designing the network7 co#puter

las and electronic #ail7 Internet connectivit$7 LAN e,penses7 and

reco##endations on planning/ e6uip#ent/ ad#inistration/ and training0

• The Pro)ised %N: Networking *eso&rces in the (edia Center

o "o&rce: School Lirar$ Cournal7 v8 n89/ p.B/ -ct 8<<:%&thor: 

Mather/ '0 "0

o %bstract: Discusses the planning and installation of a high school local

area network0

• "tandards #or "chool Networking

o "o&rce: !020E0 Cournal7 v== n</ pH8.H/ Apr 8<<:%&thors: %arlit4/ "0 D0/

et al

o %bstract: Discusses standards for the design and i#ple#entation of the

electronic data networks developed for/ and adopted $/ the )ittsurgh

)ulic Schools as district polic$0 Descries the la$ered approach whichincludes the ph$sical la$er/ the protocol la$er/ and the application la$er0

$ooks

• 'arron/ A0 E0/ and G0 W0 -rwig0 *8<<:+0 Multimedia Technologies for Training:

 An Introduction. Englewood/ %-1 Liraries (nli#ited0 'arron/ A0 E0/ and G0 W0

-rwig0 *8<<H+0 New Technologies for Education: A Beginner's Guide. Englewood/%-1 Liraries (nli#ited0?ee/ E0 *8<<+0 Networing Illustrated. Indianapolis/ IN1

ue %orporation0Lowe/ D0 *8<<+0 Networing for !ummies. San Mateo/ %A1IDG 'ooks Worlwide/ Inc0Mc%ain/ !0/ and M0 Ekelund0 *8<<B+0 "om#uter Networing for Educators. Eugene/ -"1 IS!E )ulications0Sasser/ S0/ and "0

McLaughlin0 *8<<+0 $i% &our wn (AN. New ork/ N1 MIS1)ress0Schnaidt/ )0

*8<<9+0 (AN Tutorial. SanFrancisco/ %A1 Miller Free#an )ulications0

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• Sheldon/ !0 *8<<+0 (AN TIME): Enc*clo#edia of Networing. 'erkele$/ %A1

-sorne McGraw.2ill0

World Wide We& Sites

•%n +d&cators $&ide to "chool Networks

o %&thor: 'radle$ 20 La#ont

o *: http1&&choices0cs0uiuc0edu&schools&l.thesis&inde,0ht#l

• +thernet Page 

o %&thor: %harles Spurgeon

o *:  http1&&www0ether#anage0co#&ethernet&ethernet0ht# 

• Technolog /n#or)ation

o %&thor: %IS%- S$ste#s

o *: http1&&www0cisco0co#&univercd&cc&td&doc&cisintwk&inde,0ht#

• lti)ate $&ide to Networking

o %&thor: 2ardware%entral

o *: http1&&www0hardwarecentral0co#&hardwarecentral&tutorials&8:@&8&

• % $&ide to Networking #or @ 9 12 "chools

o %&thor: Northwest Educational !echnolog$ %onsortiu#

o *: http1&&www0netc0org&networkJguide&