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Chapter4NetworkLayer1.PacketizingatthenetworklayerinvolvesA)EncapsulatingthepayloadatthesourceB)AddsaheaderthatcontainsthesourceanddestinationinformationC)DecapsulatingthepayloadatthedestinationD)Allofthechoicesarecorrect2.Routersinthepatharenotallowedto___________________________.A)fragmentthepackettheyreceiveB)decapsulatethepacketC)changesourceordestinationaddressD)Allofthechoicesarecorrect3.ThenetworklayerintheInternetprovides_________________.A)comprehensiveerrorandflowcontrol.B)limitederrorcontrol,butnoflowcontrol.C)comprehensiveerrorcontrolbutlimitedflowcontrol.D)Allofthechoicesarecorrect4.Inavirtual-circuitapproach,theforwardingdecisionisbasedonthevalueofthe_____________fieldinthepacketheader.A)sourceaddressB)destinationaddressC)labelD)Noneofthechoicesarecorrect5.Inadatagramapproach,theforwardingdecisionisbasedonthevalueofthe_____________fieldinthepacketheader.A)sourceaddressB)destinationaddressC)labelD)Noneofthechoicesarecorrect6.Theperformanceofanetworkcanbemeasuredintermsof________.A)delayB)throughputC)packetlossD)allofthechoicesarecorrect7.Transmissiondelay(time)istheratioof______________________.A)transmissionratetopacketlengthB)transmissionratetodistanceC)packetlengthtotransmissionrateD)processingtimetotransmissionrate8.Propagationdelay(time)istheratioof______________________.A)transmissionratetopropagationspeedB)propagationspeedtodistanceC)packetlengthtopropagationspeedD)distancetopropagationspeed9.Whentheloadinthenetworkreachesthenetworkcapacity,thepacketdelay___________andthenetworkthroughputreaches______________.A)increasessharply;itsminimumB)increasessharply;itsmaximumC)decreasessharply;itsminimumD)decreasessharply;itsmaximum10.Inopen-loopcongestioncontrol,policiesareapplied____________________.A)topreventcongestionbeforeithappensB)toalleviatecongestionafterithappensC)toeitherpreventcongestionbeforeithappensortoalleviatecongestionafterithappensD)Noneofthechoicesarecorrect11.The__________________techniqueisoneoftheopen-loopcongestionpolicyA)backpressureB)chokepacketC)implicitsignalingD)Noneofthechoicesarecorrect12.The__________________techniqueisoneoftheclose-loopcongestionpolicyA)acknowledgmentpolicyB)chokepacketC)discardingpolicyD)Noneofthechoicesarecorrect13.IPisa_________protocol.A)connection-orientedunreliableB)connection-orientedreliableC)connectionlessunreliableD)connectionlessreliable14.AnHLENvalueofdecimal10means_______.A)thereare10bytesofoptionsB)thereare10bytesintheheaderC)thereare40bytesofoptionsD)thereare40bytesintheheader15.Ifthefragmentoffsethasavalueof100,itmeansthat_______.A)thedatagramhasnotbeenfragmentedB)thedatagramis100bytesinsizeC)thefirstbyteofthedatagramisbyte800D)Noneofthechoicesarecorrect16.Whatisneededtodeterminethenumberofthelastbyteofafragment?A)offsetnumberB)totallengthC)bothoffsetnumberandthetotallengthD)Noneofthechoicesarecorrect17.TheIPheadersizeis_______byteslong.A)20to60B)20C)60D)Noneofthechoicesarecorrect18.PacketsintheIPlayerarecalled_________.A)segmentsB)datagramsC)framesD)Noneofthechoicesarecorrect19.Thetotallengthfielddefinesthetotallengthofthedatagram_________.A)includingtheheaderB)excludingtheheaderC)excludingtheoptionlengthD)Noneofthechoicesarecorrect20.Whenadatagramisencapsulatedinaframe,thetotalsizeofthedatagrammustbelessthanthe_______.A)MUTB)MATC)MTUD)Noneofthechoicesarecorrect21.AnIPv4addressisnormallyrepresentedinbase____indotted-decimalnotation.A)16B)256C)10D)Noneofthechoicesarecorrect22.Inclassfuladdressing,theIPv4addressspaceisdividedinto_______classes.A)3B)4C)5D)Noneofthechoicesarecorrect23.Thenumberofaddressesassignedtoanorganizationinclasslessaddressing_______.A)canbeanynumberB)mustbeamultipleof256C)mustbeapowerof2D)Noneofthechoicesarecorrect24.Thefirstaddressassignedtoanorganizationinclasslessaddressing_______.A)mustbeevenlydivisiblebythenumberofaddressesintheorganizationB)mustbedivisibleby128C)mustbelongtooneoftheA,B,orCclassesD)Noneofthechoicesarecorrect25.Insubnetting,thenumberofaddressesineachsubnetmust_______.A)beapowerof2B)beamultipleof128C)bedivisibleby128D)Noneofthechoicesarecorrect26.WhatisthedefaultprefixlengthforclassAinCIDRnotation?A)9B)8C)16D)Noneofthechoicesarecorrect27.WhatisthedefaultprefixlengthforclassBinCIDRnotation?A)9B)8C)16D)Noneofthechoicesarecorrect28.WhatisthedefaultprefixlengthforclassCinCIDRnotation?A)24B)8C)16D)Noneofthechoicesarecorrect29.DHCPisa(an)___________layerprotocol.A)applicationB)transportC)networkD)data-link30.InDHCP,theclientuses________portandtheserveruses_________port.A)anephemeral;awell-knownB)awell-known;awell-knownC)awell-known;anephemeralD)Noneofthechoicesarecorrect31.DHCPusestheservicesof_______.A)UDPB)TCPC)IPD)Noneofthechoicesarecorrect32._________allowsasitetouseasetofprivateaddressesforinternalcommunicationandasetofglobalInternetaddressesforcommunicationwiththerestoftheworld.A)DHCPB)NATC)IMCPD)Noneofthechoicesarecorrect33.Theideaofaddressaggregationwasdesignedtoalleviatetheincreaseinroutingtableentrieswhenusing________addressing.A)classfulB)classlessC)classfulorclasslessD)Noneofthechoice