计算机网络教程自顶向下方法选择题及答案-Chapt-4-Network-Layer-QUIZZ.docx

Chapter4NetworkLayer.PacketizingatthenetworklayerinvolvesA) EncapsulatingthepayloadatthesourceB) AddsaheaderthatcontainsthesourceanddestinationinformationC) DecapsulatingthepayloadatthedestinationD) Allofthechoicesarecorrect2.Routersinthepatharenotallowedto.A) fragmentthepackettheyreceiveB) decapsulatethepacketC) changesourceordestinationaddressD) Allofthechoicesarecorrectl l J VH/ ABCDThenetworklayerintheIprehensiveerrorandflowcontrol,limitederrorcontrol,butnoflowcontrol,comprehensiveerrorcontrolbutlimitedflowcontrol.Allofthechoicesarecorrect4.Inavirtual-circuitapproach,theforwardingdecisionisbasedonthevalueofthefieldinthepacketheader.a)b)qd)sourceaddressdestinationaddresslabelNoneofthechoicesarecorrect5.Inadatagramapproach,theforwardingdecisionisbasedonthevalueofthefieldinthepacketheader.A)B)QD)sourceaddressdestinationaddresslabelNoneofthechoicesarecorrect6.Theperformanceofanetworkcanbemeasuredintermsof.A)B)QD)delaythroughputpacketlossallofthechoicesarecorrect7.Transmissiondelay(time)istheratioof.A) transmissionratetopacketlengthB) transmissionratetodistanceC) packetlengthtotransmissionrateD) processingtimetotransmissionrate8.l ) ¼n< IHf ABCDPropagationdelay(time)istheratioof.transmissionratetopropagationspeedpropagationspeedtodistancepacketlengthtopropagationspeeddistancetopropagationspeed9.Whentheloadinthenetworkreachesthenetworkcapacity,thepacketdelayandtheA)B)QD)networkthroughputreaches.increasessharply;itsminimumincreasessharply;itsmaximumdecreasessharply;itsminimumdecreasessharply;itsmaximum10.Inopen-loopcongestioncontrol,policiesareapplied.A) topreventcongestionbeforeithappensB) toalleviatecongestionafterithappensC) toeitherpreventcongestionbeforeithappensortoalleviatecongestionafterithappensD) Noneofthechoicesarecorrect11.Thetechniqueisoneoftheopen-loopcongestionpolicyA) backpressureB) chokepacketC) implicitsignaling- a12.heA)B)QD)13.lplA)B)QD)D) Noneofthechoicesarecorrecttechniqueisoneoftheclose-loopcongestionpolicyacknowledgmentpolicychokepacketdiscardingpolicyNoneofthechoicesarecorrectprotocol.connection-orientedunreliableconnection-orientedreliableconnectionlessunreliableconnectionlessreliable14.AnHLENvalueofdecimal10means.A) thereare10bytesofoptionsB) thereare10bytesintheheaderC) thereare40bytesofoptionsD) thereare40bytesintheheader15.Ifthefragmentoffsethasavalueof100,itmeansthat.A) thedatagramhasnotbeenfragmentedB) thedatagramis100bytesinsizeC) thefirstbyteofthedatagramisbyte800D) Noneofthechoicesarecorrect16.Whatisneededtodeterminethenumberofthelastbyteofafragment?A) offsetnumberB) totallengthC) bothoffsetnumberandthetotallengthD) Noneofthechoicesarecorrect17.TheIPheadersizeisbyteslong.A) 20to60B) 20C) 60D) Noneofthechoicesarecorrect18.A)B)0D)PacketsintheIPlayerarecalled.segmentsdatagramsframesNoneofthechoicesarecorrect19.Thetotallengthfielddefinesthetotallengthofthedatagram.A) includingtheheaderB) excludingtheheaderC) excludingtheoptionlengthD) Noneofthechoicesarecorrect20.Whenadatagramisencapsulatedinaframe,thetotalsizeofthedatagrammustbelessthanthe¼l %)/ ¼1 H ABCDMUTMATMTUNoneofthechoicesarecorrect21.AnIPv4addressisnormallyrepresentedinbaseindotted-decimalnotation.A) 16B) 256C) 10D) Noneofthechoicesarecorrectintoclasses.5Noneofthechoicesarecorrect23.ThenumberofaddressesassignedtoanorganizationinclasslessaddressingA) canbeanynumberB) mustbeamultipleof256C) mustbeapowerof2D) Noneofthechoicesarecorrect24.Thefirstaddressassignedtoanorganizationinclasslessaddressing.A) mustbeevenlydivisiblebythenumberofaddressesintheorganizationB) mustbedivisibleby128C) mustbelongtooneoftheA,B,orCclassesD) Noneofthechoicesarecorrect25lnA)B)QD)subnetting,thenumberofaddressesineachsubnetmust.beapowerof2beamultipleof128bedivisibleby128Noneofthechoicesarecorrect26.WhatisthedefaultprefixlengthforclassAinCIDRnotation?9816NoneofthechoicesarecorrectA)B)Q627.WhatisthedefaultprefixlengthforclassBinCIDRnotation?9816Noneofthechoicesarecorrecta)b)qd)28.WhatA)B)QisthedefaultprefixlengthforclassCinCIDRnotation?24816D)Noneofthechoicesarecorrect29.DHCPisa(an)layerprotocol,applicationtransportnetworkdata-linkA)B)QD)30.InDHCBtheclientusesportandtheserverusesport,anephemeral;awell-knownawell-known;awell-knownawell-known;anephemeralNoneofthechoicesarecorrectA)B)QD)31.DHCPusestheservicesof.UDPTCPIPNoneofthechoicesarecorrecta)b)c)d32.allowsasitetouseasetofprivateaddressesforinternalcommunicationandasetofglobalInternetaddressesforcommunicationwiththerestoftheworld.A) DHCPB) NAC) IMCPD) Noneofthechoicesarecorrect33.Theideaofaddressaggregationwasdesignedtoalleviatetheincr