【MOOC】IntroductionofInformationCommunicationNetwork-東南大學中國大學慕課MOOC答案Test1、【單選題】Whichofthefollowingdescriptionsofnetworkclassificationiswrong本題答案：【Anetworkconnectingdigitalterminaldevicessuchascomputerswithin10moftheuser'scomputerisaWSN】2、【單選題】WhichofthefollowingdescriptionsofWANcharacteristicsiswrong本題答案：【ThecoretechnologyofWANislineswitchingtechnology】3、【判斷題】Thecomputernetworkiscomposedofnetworkhardwaresystemandnetworksoftwaresystem.本題答案：【正確】4、【判斷題】Ingeneral,networknodeshaveduality,whichcanbeusedasbothaccessnodesandtransfernodes.本題答案：【正確】Test1、【單選題】Amongfollowingdescriptionsofthedatagramtransmissionmode,whichiswrong?本題答案：【Datagrammodeissuitableforlongmessageandsessioncommunication】2、【判斷題】Messageexchangeadoptsstore-and-forwardmechanism.本題答案：【正確】3、【判斷題】Atpresent,packetswitchingisthemostcommonlyusedswitchingmodeincommunicationnetworks.本題答案：【正確】4、【判斷題】Thedelayofmessageexchangeisveryshort,soitisstillthemainexchangemode.本題答案：【錯誤】5、【判斷題】Circuitswitchingisdividedintothreestages:establishingconnection,communicatingandreleasingconnection.本題答案：【正確】Test1、【單選題】WhichiswrongamongthefollowingdescriptionsoftheOSIenvironment本題答案：【ThephysicaltransmissionmediumconnectingthehostisincludedintheOSIenvironment】2、【單選題】AmongthefollowingdescriptionsofthedatatransmissionprocessinOSIenvironment,thewrongdescriptionis本題答案：【Thepresentationlayeronlyexchangesdataformatswithoutaddingprotocolheaders】3、【單選題】IntheOSIreferencemodel,thefirstleveltoprovideend-to-endservicesfrombottomtotopis本題答案：【Transportlayer】4、【單選題】Amongthefollowingcomponents,whichdoesnotbelongtothenetworkarchitecture本題答案：【Protocoldetails】5、【單選題】ThenetworklayerprotocolinTCP/IPsystemprovides本題答案：【Connectionlessandunreliablepacketservice】HomeworkUnittest1、【單選題】Whichiswrongamongthefollowingdescriptionsofnetworkprotocolsandprotocolelements?本題答案：【Protocolpresentsnetworkfunctions】2、【單選題】Whichiswrongamongthefollowingdescriptionsoftheconceptofnetworkarchitecture本題答案：【AllcomputernetworksshouldfollowOSIarchitecture.】3、【單選題】Whichiswrongamongthefollowingadvantagesoftheresearchmethodofnetworkarchitecture本題答案：【AllowingforinterlayercommunicationisasignofflexibilityofOSIreferencemodel】4、【單選題】WhichiswrongamongthefollowingdescriptionofthebasicconceptsofOSIreferencemodel本題答案：【Term‘Open’inOSIReferenceModelreferstobeingabletobeusedforanykindofoperatingsystemforcomputer】5、【單選題】Whichiswrongamongthefollowingdescriptionsofthe7-leveldivisionprincipleofOSIreferencemodel本題答案：【Eachhostinthenetworkcanhavedifferentlevels】6、【單選題】Whichiswrongamongthefollowingdescriptionsofbasicfeaturesofthephysicallayer本題答案：【Datatransmissionunitisabyte】7、【單選題】Amongthefollowingbasicfeatures(orproperties)ofthedatalinklayer,whichisthewrongdescription本題答案：【Datalinkcanbeestablishedafterthephysicalconnectionisreleased】8、【單選題】Amongthefollowingbasicfeaturesofthenetworklayer,whichisthewrongdescription本題答案：【Realizingthefunctionsofflowcontrol,congestioncontrolandnetworksecurity】9、【單選題】Amongthefollowingbasicfeaturesofthetransportlayer,whichisthewrongdescription本題答案：【Adjacenthighlayeristhepresentationlayer】10、【單選題】WhichiswrongamongthefollowingdescriptionsofOSIenvironment本題答案：【ThephysicaltransmissionmediumconnectingthehostisincludedintheOSIenvironment】11、【單選題】AmongthefollowingdescriptionsofthedatatransmissionprocessinOSIenvironment,thewrongdescriptionis本題答案：【Thepresentationlayeronlyexchangesdataformatswithoutaddingprotocolheaders】12、【單選題】Amongthefollowingcharacteristicsofthetransportlayer,whichiswrong本題答案：【Dataunitofprotocolisapacket】13、【單選題】Whatiscorrectindescribingtherelationshipbetweenthenthlayerandthen+1layerinOSIreferencemodel本題答案：【Thenthlayerprovidesservicesforthen+1thlayer】14、【單選題】InOSIreferencemodel,thefirstleveltoprovideend-to-endservicesfrombottomtotopis本題答案：【Transportlayer】15、【單選題】Amongthefollowingcomponents,whichdoesnotbelongtonetworkarchitecture本題答案：【Agreementdetails】16、【單選題】ThenetworklayerprotocolinTCP/IPsystemprovides本題答案：【Connectionlessandunreliablepacketservice】17、【單選題】Theresourcessharedbythecomputernetworkare本題答案：【Computersoftware,hardwareanddata】18、【單選題】Whichofthefollowingdescriptionsofnetworkclassificationiswrong本題答案：【Anetworkconnectingdigitalterminaldevicessuchascomputerswithin10moftheuser'scomputerisaWSN】19、【單選題】WhichofthefollowingdescriptionsofWANcharacteristicsiswrong本題答案：【ThecoretechnologyofWANislineswitchingtechnology】20、【單選題】Amongthefollowingdescriptionsofbroadbandmetropolitanareanetwork,thewrongdescriptionis本題答案：【SwitchesinLayer2isthecoreequipmentofbroadbandmetropolitanareanetwork】21、【判斷題】Thecomputernetworkiscomposedofnetworkhardwaresystemandnetworksoftwaresystem.本題答案：【正確】22、【判斷題】Thehostcomputerbelongstotheswitchingnodeofthenetworknodeinthecomputernetwork.本題答案：【錯誤】23、【判斷題】Ingeneral,networknodeshaveduality,andcanbeusedasbothaccessnodesandtransfernodes.本題答案：【正確】24、【判斷題】Physicallinksdonothavethecapabilityofdatatransmissioncontrol.本題答案：【正確】25、【判斷題】Commontransmissionmediaincomputernetworksincludetwistedpair,coaxialcableandopticalfiber.本題答案：【正確】Test1、【單選題】Amongthefollowingfourtransmissionmedia，whichhasthewidestbandwidth,thesmallestsignaltransmissionattenuationandthestrongestanti-interferencecapability?本題答案：【Opticalfiber】2、【單選題】Whatarethebenefitsofshieldingincables?本題答案：【Reduceelectromagneticinterferenceradiation】3、【判斷題】Physicallayeristhespecificphysicaldeviceorspecifictransmissionmediumconnectingthecomputers.本題答案：【錯誤】4、【判斷題】Incomputernetworks,carriersusedtotransmitinformationsuchastwistedpair,coaxialcableandopticalfiberarecalledtransmissionmedia.本題答案：【正確】5、【判斷題】Adatatransmissionmodethatallowssignalstobetransmittedintwodirectionsbutcanonlybetransmittedinonedirectionateachmomentiscalledsimplexcommunication.本題答案：【錯誤】Test1、【單選題】Thebasisofanalogsignaltransmissioniscarrierwave.Whichisnotthe3elementsofcarrierwave?本題答案：【Period】2、【單選題】ThefollowingfigureshowsManchestercoding.Whatisthebinarydatashowninthisfigure?本題答案：【01011】3、【單選題】Inordertoincreasethetransmissiondistanceoftheanalogtransmissionsystem,whatequipmentshouldbeused?本題答案：【Amplifier】4、【判斷題】Analogcommunicationsystemusuallyconsistsofsource,modulator,channel,demodulatorandsink.Theelectricalsignalbeforemodulationiscalledanalogsignal,andthemodulatedsignaliscalleddigitalsignal.本題答案：【錯誤】5、【判斷題】Inanalogdatacommunicationsystem,digitaldatacanbemodulatedaccordingtodifferentelementsofcarrierwave.Therearethreemethodsofmodulatingsignals,namelyamplitudekeying,frequencyshiftkeyingandphaseshiftkeying.本題答案：【正確】Test1、【單選題】Whichiswrongamongthefollowingdescriptionsoftheconceptoftimedivisionmultiplexing?本題答案：【Statistictimedivisionmultiplexingassigntimeslicestoeachchannelinadvance】2、【單選題】Whichiswrongamongthefollowingdescriptionsofthetechnicalcharacteristicsofstatisticaltimedivisionmultiplexing?本題答案：【TheEnglishabbreviationofstatisticaltimedivisionmultiplexingisATDM】3、【判斷題】Multiplexingtechnologycanbedividedintothreebasicmodes:frequencydivisionmultiplexing,wavelengthdivisionmultiplexingandtimedivisionmultiplexing.本題答案：【正確】4、【判斷題】Theprocessofpulsecodingmodulationcanbesimplydividedintotwoprocesses:samplingandcoding.本題答案：【錯誤】5、【判斷題】Incellularmobilecommunicationsystems,therearethreecommonlyusedmultipleaccesstechnologies:frequencydivisionmultipleaccess,timedivisionmultipleaccessandcodedivisionmultipleaccess.本題答案：【正確】Test1、【單選題】InATMtechnology,cellsarethebasicunitofdatatransmission,andtheirlengthis:本題答案：【53B】2、【單選題】Whichisincorrectamongthefollowingdescriptionsofpacketswitching?本題答案：【Thepacketswitchingtechnologyhashigherrorrateofdatatransmissionandlowlineutilizationrate】3、【單選題】WhatisthemeaningofasynchronousinAsynchronousTransferMode(ATM)technology?本題答案：【InsertsintoATMcellsatanytime】4、【單選題】WhichiswrongamongthefollowingdescriptionsofT1carrier?本題答案：【ThedatatransmissionrateofT1carrieris2.048Mbps】5、【單選題】WhichiswrongamongthefollowingdescriptionsofthecomparisonbetweenADSLandHFC?本題答案：【ADSLbackboneusesopticalfiberandHFCbackboneusesbroadbandcoaxialcable】HomeworkUnittest1、【單選題】Amongthefollowingdescriptionsofthephysicallayer,whichiswrong?本題答案：【PhysicallayershieldsthedifferencebetweenEthernetandIP】2、【單選題】Amongthefollowingdescriptionsofdatatransmissionrate,whichiswrong?本題答案：【Commondatatransmissionrateunitsare:1Mbps=1.024×10^6bps】3、【單選題】WhichiswrongamongthefollowingdescriptionsofNyquist'scriteria?本題答案：【Usedtocalculatebandwidthandrateinthestateofrandomnoise】4、【單選題】IfthefollowingisaManchesterencodedwaveformof8-bitdata,whatisthisdata?本題答案：【01001011】5、【單選題】Whichiswrongamongthefollowingstatementsaboutsatellitecommunication?本題答案：【Theadvantagesofsatellitecommunicationarethatitisnotaffectedbyclimateanditsbiterrorrateisverylow.】6、【單選題】WhenFSKmodulationisperformedonasignal,andifthecarrierfrequencyisfcandtheoriginal/modulatedsignalfrequenciesaref1andf2respectively(f1f2),whatistherelationshipbetweenthethree?本題答案：【fc-f1=f2-fc】7、【單選題】Whichisthemodulationanddemodulationtechnologymainlyusedamongthefollowingcommunicationmodes?本題答案：【Analogchanneltransmitsdigitaldata】8、【單選題】Whatisthechannelcommunicationmodeinwhichbothcommunicationpartiescantransmitdatasimultaneouslyatthesametime?本題答案：【Fullduplexcommunication】9、【單選題】Generallyspeaking,forhigh-speedlocalareanetworkswithlargevolume,whichshouldbeselectedinordertoobtainhigherperformanceamongfollowingmedia?本題答案：【OpticalFiber】10、【單選題】Whatarethethreebasicformsofanalogdatacoding?本題答案：【ASK,FSK,PSK】11、【單選題】Whenadigitalsignalistransmittedinananalogtransmissionsystem,whatarerequiredatthetransmittingandthereceivingendsrespectively?本題答案：【ModulatorandDemodulator】12、【單選題】Dividingthefrequencybandwidthofthephysicalchannelintoseveralsubchannels,eachsubchanneltransmittingonesignal.Whatisthismultiplexingtechnologycalled?本題答案：【Frequencydivisionmultiplex】13、【單選題】Duringdatatransmission,localtelephonenetworkhasaphysicalconnectionlinebetweenthesourcenodeandthedestinationnode,whichconstituteintermediatenodes.Whatisthetechnologyadoptedbythislocaltelephonenetworkcalled?本題答案：【LineSwitching】14、【單選題】Whichoneamongthefollowingmultiplexingtechnologieshasthefunctionofdynamicallyallocatingtimeslots?本題答案：【Statisticaltimedivisionmultiplex】15、【單選題】Indigitalcommunication,whatisthetechnologytokeepthetimereferencebetweenthetransceiverandthetransceiverconsistent?本題答案：【SynchronizationTechnology】16、【單選題】Whatisthecodingmethodwhichrepresentsthedigitalsignal1,0bychangingthephasevalueofthecarriersignal?本題答案：【PSK】17、【單選題】Shannon'stheoremdescribestherelationshipbetweenbandwidthandratefromaquantitativepointofview.IntheformulaofShannon'stheorem,theparametersrelatedtothemaximumtransmissionrateofthechannelmainlyincludeschannelbandwidthand()?本題答案：【Signal-to-NoiseRatio】18、【單選題】Thepacketswitchingmodeistodividealongmessageintoseveralshorterpacketswithafixedmaximumlength.Differentfrompacketswitching,packetswitchinghas()?本題答案：【GroupNumber】19、【單選題】Generallyspeaking,digitaltransmissioncangethighersignalqualitythananalogtransmission,because?本題答案：【Therepeatercanregeneratedigitalpulsestoremovesignaldistortion,andtheamplifieramplifiestheanalogsignalaswellastheanalogsignaldistorted】20、【單選題】Amongthefollowingdataexchangemodes,thetransmissiondelayofdatathroughthenetworkislongandunstable.Whichcannotbeusedforvoicedatatransmission?本題答案：【Messageexchange】21、【判斷題】Datatransferrateisthenumberofbytestransferredpersecond.本題答案：【錯誤】22、【判斷題】Modemisonlyusedtoconvertdigitalsignalsintoanalogsignalsandtransmitthemontheline.本題答案：【錯誤】23、【判斷題】ManchestercodeanddifferentialManchestercodebelongtoself-containedclockcode.本題答案：【正確】24、【判斷題】Bitratedescribesthenumberofbinarybitsthatmakeupthecodetransmittedpersecondincomputercommunication.本題答案：【正確】25、【判斷題】Datasentbystatisticaltimedivisionmultiplexingneedtohaveaddressesofbothtransceiverandtransceiver.本題答案：【錯誤】Tests1、【單選題】Whatdoesnotbelongtothethreepossibleservicesthatareprovidedbydatalinklayer?本題答案：【Connection-orientedservicewithoutacknowledgement】2、【判斷題】Thedatalinklayerencapsulatesthepacketsobtainedfromthenetworklayerintoframesfortransmission,eachframecontainingaframeheaderandapayloaddomain.本題答案：【錯誤】3、【判斷題】Inbytefilling,iftheescapedbyteappearsinthemiddleofthedata,thereisnoneedtoinserttheescapedbyteinfront.本題答案：【錯誤】4、【判斷題】Inbitfilling,whenthesender'sdatalinklayerencountersfiveconsecutivebits1inthedata,itautomaticallyfillsonebit0intheoutputbitstream.Andthereisnoneedtofillwhen5consecutivebits0areencountered.本題答案：【正確】5、【判斷題】Sometimesduetohardwareproblems,someframesarecompletelylost.Atthistime,thereceiverwillnotrespond,whilethesenderhasbeenwaitingbecauseithasnotreceivedfeedbackinformation.Introducingtimersinthedatalinklayercansolvethisproblem.本題答案：【正確】Tests1、【判斷題】Inpolynomialcoding,arithmeticoperationsofpolynomialshavecarryinadditionandborrowinsubtraction.本題答案：【錯誤】2、【判斷題】Errorcontrolcodescanbedividedintoerrordetectioncodesanderrorcorrectioncodes.Amongthem,theerrordetectioncodeisthecodeofautomaticerrordetection;Anerrorcorrectingcodeisacodethatcannotonlydetecterrorsbutalsoautomaticallycorrectthem.本題答案：【正確】3、【判斷題】Theso-callederroristhatindatacommunication,thedatareceivedafterthedatathroughthecommunicationchannelisinconsistentwiththedatasent.本題答案：【正確】4、【判斷題】Generallyspeaking,mostoftheerrorsintransmissionarecausedbynoise.Errorscausedbythermalnoisearecalledbursterrors,whileerrorscausedbyimpactnoisearecalledrandomerrors.本題答案：【錯誤】5、【判斷題】Intheoddcheckscheme,thecheckbitofbinarysequence0101101is0.本題答案：【錯誤】Tests1、【單選題】Indatacommunication,whendatatransmissionerrorsoccur,theerrorcontrolmethodthatthesenderdoesnotneedtoretransmitthedatais?本題答案：【FEC】2、【單選題】TheerrordetectionandcorrectioncapabilityofacodedependonitsHammingdistance.Inordertodetectd-biterrors,whatisthecodewithHammingdistance?本題答案：【d+1】3、【單選題】WhatistheframesynchronizationmethodusedbyHDLCprotocol?本題答案：【Beginningandtailmarkmethodusingbitfilling】4、【判斷題】Inasimplexstop-waitprotocol,datatrafficissimplex,onlyfromthesendertothereceiver,sothecommunicationchannelbetweenthetwodatalinklayersonlyneedstohavethecapabilityofunidirectionaltransmissionofinformation.本題答案：【錯誤】5、【判斷題】Themostbasicfunctionofthedatalinklayeristoprovidereliableandtransparentservicestousersatthislayer.本題答案：【正確】Tests1、【單選題】Whatkindofcontrolisflowcontrolactually?本題答案：【Dataflowofthesender】2、【單選題】Theerrorcontrolmethodbywhichthereceivingendcannotonlydetecttheerror,butalsodeterminethelocationwheretheerroroccurred.Whatisthiscontrolmethod?本題答案：【ForwarderrorcorrectionFEC】3、【單選題】Fromthepointofviewofslidingwindow,whenthetransmissionwindow=1andthereceptionwindow=1,whatistheequivalentoffeedbackretransmission?本題答案：【Stopandwait】4、【判斷題】Intheslidingwindowprotocol,thesendingwindowofthesenderandthereceivingwindowofthereceivermusthavethesameupperandlowerbounds.本題答案：【錯誤】5、【判斷題】Intheactualmeasurementofadatatransmissionsystem,themorebinarybitsaremeasured,thecloseritwillbetothetruebiterrorrate.本題答案：【正確】Tests1、【單選題】WhichlayerdoesSLIPorPPPbelongto?本題答案：【Datalinklayer】2、【單選題】SupposeaWANhasfournetworksconnectedinparallelbydedicatedtelephonelinesandusingTCP/IP,NWLINK,andNETBEUIprotocols.Ifcommunicationbetweenthesenetworksrequiresdatacompression,whichshouldbeusedamongthefollowingdial-upcommunicationprotocols?本題答案：【PPP】3、【單選題】AmongthecommonoperationmodesinHDLC,whatisthetransmissionprocessthatcanonlybestartedbythemasterstation?本題答案：【A,B,Ccanall】4、【單選題】WhichdoesnotbelongtotheTCP/IPprotocolfamilyamongthefollowingprotocols?本題答案：【HDLC】5、【判斷題】InPPPprotocol,LinkControlProtocol/LCPisusedtoestablish,configure,manageandtestdatalinkconnections.AndtheNetworkControlProtocol/NCPisusedtoestablishandconfiguredifferentnetworklayerprotocols.本題答案：【正確】HomeworkUnitetest1、【單選題】Inordertocarryouterrorcontrol,thetransmitteddataframemustbechecked.WhichkindofverificationmethodiswidelyusedinLAN?本題答案：【CyclicRedundancy(CRC)】2、【單選題】WhichisthemostaccuratedescriptionofthecharacteristicsofCRCamongthefollowingoptions?本題答案：【Cancheckoutmorethan99%oferrors】3、【單選題】Thetypesoferrorsindatatransmissionmainlyincludebursterrorsand()?本題答案：【Randomerror】4、【單選題】Inanidealchannel,dataiserror-freefromthesendingendtothereceivingend,butinpracticalapplication,datatransmissionwillproduceerrors.Whichoneisnotafactoraffectingtheerrorduetophysicaltransmissionmedium?本題答案：【Thecompressionratioofdataistoohigh,resultinginerrorsintransmissionthatcannotbeovercome】5、【單選題】TheerrordetectionandcorrectioncapabilityofacodedependonHammingdistance.Inordertocorrectd-biterrors,whatisthecodewithHammingdistance?本題答案：【2d+1】6、【單選題】Whatisthecheckcodethatcandetectallodderrors,singlebiterrors,doublebiterrorsandallbursterrorswhicharelessthanorequaltothelengthofthecheckbit?本題答案：【CRC】7、【單選題】Flowcontrolisoneofthebasicfunctionsofthedatalinklayer.Regardingflowcontrol,whichoneiscorrectamongfollowingstatements?本題答案：【Notonlydoesthedatalinklayerhaveflowcontrol,buttheflowcontrolobjectsofeachlayeraredifferent】8、【單選題】Whichofthethreeservicesprovidedbythedatalinklayertothenetworklayerhasthelowestqualityofserviceandcanbeusedtotransmitinformationwithhighreal-timerequirementsinoccasionswithlowlinebiterrorrate?本題答案：【Connectivity-freeservicewithoutconfirmation】9、【單選題】Whichdoesnotbelongtothedatalinklayeramongfollowingfunctions?本題答案：【Circuitmanagementfunction】10、【單選題】Thezero-bitinsert/deletemethodstatesthatifthesenderisinasequenceofbitsbetweentwoFflags.Howmanysuccessiveonesaredetected,ifitincrementsthenumberbyone,regardlessofwhetherthebitafteritis0or1.本題答案：【5】11、【單選題】Assumethatthedatalinklayeradoptsgo-back-Nmodeforerrorcontrol,andthesenderhasalreadysenttheframesnumberedfrom0to7.Whenthetimertimesoutandtheconfirmationofframe1doesnotreturn,whatisthenumberofframesthatthesenderneedstoretransmit?本題答案：【7】12、【單選題】AmongthecommonoperationmodesinHDLC,whichonecanstartthetransmissionprocessbyboththemasterstationandtheslavestation?本題答案：【Asynchronousbalancedmode】13、【單選題】Inordertoavoidthedisappearanceofframesduringtransmission,whatmethoddoesthedatalinklayeradopt?本題答案：【Timer’stimeoutretransmission】14、【單選題】Whatistheprobabilitythatbinarybitsaretransmittedincorrectlyinthedatatransmissionsystemcalled?本題答案：【Errorrate】15、【單選題】Whichiswrongamongthefollowingdescriptionsofbiterrorrate?本題答案：【Biterrorrateoftheactualapplicationdatatransmissionsystemcanreachzero】16、【單選題】Whichwillonlyretransmitthewrongdataframeamongthefollowingerrorcontrolmethods?本題答案：【Selectandretransmit】17、【單選題】Whichcontrolmethodisprimarilyusedbytheslidingwindowprotocol?本題答案：【Flowcontrol】18、【單選題】InCRCcodecalculation,abinarybitstringcanbeassociatedwithaunarypolynomialcontainingonly0or1coefficients.Forexample,thepolynomialcorrespondingtobitstring101101is（）?本題答案：【x^5+x^3+x^2+1】19、【單選題】Iftheframesequencenumberofthedatalinkoccupies4bits,themaximumsenderwindowshouldbe?本題答案：【15】20、【單選題】InCRCcyclicredundancycalculation,abinarybitstringcanbecorrespondedtoaunarypolynomialwithonlytwocoefficientsof0or1.Forexample,thestringofbinarynumberscorrespondingtothepolynomialx^5+x^4+x+1shouldbe?本題答案：【110011】21、【判斷題】Connectionlessservicewithoutconfirmationisverysuitableforreal-timecommunication,suchasvoicetransmission.本題答案：【正確】22、【判斷題】Indataframes,whencontrolcharactersappearinthetransmitteddata,appropriatemeasuresmustbetakensothatthereceivingpartydoesnotmistakethedataforcontrolinformation.Thisensuresthatthedatalinklayerisconnection-oriented.本題答案：【錯誤】23、【判斷題】Thecommonlyusedmethodsofframesynchronizationarecharactercountingmethod,delimitermethodwithbytefilling,delimitermarkmethodwithbitfillingandphysicallayercodingviolationmethod.本題答案：【正確】24、【判斷題】CRCverificationcannotabsolutelyensurethecorrectverificationofdata.本題答案：【正確】25、【判斷題】Animportantparametertomeasurethecodingperformanceisthebiterrorrate.本題答案：【錯誤】Tests1、【判斷題】ThesequentialtransmissionofdatapacketsismainlycompletedbyMACsublayer.本題答案：【錯誤】2、【判斷題】TheexistenceofMACsublayershieldsthedifferencesofdifferentphysicallinks.本題答案：【正確】3、【判斷題】Conflictreferstothesignalconflictthatwilloccurwhentwoormoreusersapplyforcommunicationatthesametimeandinthesamelink.本題答案：【正確】4、【判斷題】Staticchannel-allocationschemeisnotsuitableforoccasionswithmanyusersandlargetrafficchanges.本題答案：【正確】Tests1、【判斷題】NoconflictwilloccurduringthecompetitioncycleintheCSMA/CDprotocol.本題答案：【錯誤】2、【判斷題】Inordertosolvetheproblemthatthebasicbitmapprotocolcannotbewellexpanded,thesolutionistousebinarystationaddresses.本題答案：【正確】3、【判斷題】Non-persistentCSMAprotocolwilllistentothechannelbeforeeachtransmission.Ifthechannelisbusy,itwillcontinuetolistenandsendassoonasthechannelisidle.本題答案：【錯誤】Tests1、【單選題】WhichiswrongthefollowingdescriptionofEthernetprotocol,theerroris本題答案：【Noconflictisfoundwhenthehostsendsthepreamblecodeofaframeandthepreambledelimiteroftheframe,thenthehostcancontinuetosend】2、【單選題】WhichiswrongamongthefollowingdescriptionsofEthernetframereceptionerror本題答案：【Frameaddresserrormeansthatthephysicaladdressofthereceivedframeisnottheaddressofthissite】3、【單選題】WhichiswrongamongthefollowingdescriptionsofthephysicaladdressofEthernet本題答案：【ThephysicaladdressofnetworkcardiswrittenintotheEPROMofhostcomputer】Tests1、【單選題】Whichiswrongamongthefollowingdescriptionsofthebasicfunctionsofswitch本題答案：【ExecutingRIProutingprotocol】2、【單選題】Aswitchhas24portswith10/100Mbpsandtwo1Gbpsports.Ifallportsareoperatinginfullduplex,thetotalbandwidthoftheswitchisthemaximum本題答案：【8.8Gbps】3、【判斷題】Oneofthemainfeaturesofswitchinglansistheirlowswitchingtransmissionlatency.ThedelaytimeofLANswitchishigherthanthatofbridge,butlowerthanthatofrouter本題答案：【錯誤】HomeworkUnittest1、【單選題】Whichiswrongamongthefollowingdescriptionsofthetermssharedmedia,multipleaccessandconflict.Statement()iswrong.本題答案：【Thecorrespondingphysicallayerprotocolis10Base-T】2、【單選題】WhichiswrongamongthefollowingdescriptionsofLAN’sapplicationenvironment本題答案：【Forindustrialenvironmentsandapplicationsthatrequirestrictreal-timedatatransmission,Ethernetprotocolisrecommended】3、【單選題】WhichiswrongamongthefollowingdescriptionsofEthernetprotocol本題答案：【Noconflictisfoundwhenthehostsendsthepreamblecodeofaframeandthepreambledelimiteroftheframe,thenthehostcancontinuetosend】4、【單選題】Whichiswrongamongthefollowingdescriptionsoftherandomdelayretransmissionmechanism本題答案：【Themaximumpossibledelaytimeis1024timeslices】5、【單選題】WhichiswrongamongthefollowingdescriptionsofEthernetframereceptionerror本題答案：【Frameaddresserrormeansthatthephysicaladdressofthereceivedframeisnottheaddressofthissite】6、【單選題】Whichiswrongamongthefollowingdescriptionsofnetworkcard本題答案：【Networkcardrealizesthebridgefunctionofconnectingwithotherlocal-areanetworks】7、【單選題】WhichiswrongamongthefollowingdescriptionsofthephysicaladdressofEthernet本題答案：【ThephysicaladdressofnetworkcardiswrittenintotheEPROMofhostcomputer】8、【單選題】WhichiswrongamongthefollowingdescriptionsofthestandardnamingmethodforEthernetphysicallayer本題答案：【Ydenotesthemaximumlengthofthenetworksegmentin1000m】9、【單選題】Whichiswrongamongthefollowingdescriptionsofthebasicfunctionsofswitch本題答案：【ExecutingRIProutingprotocol】10、【單選題】Aswitchhas24portswith10/100Mbpsandtwo1Gbpsports.Ifallportsareoperatinginfullduplex,thetotalbandwidthoftheswitchisthemaximum本題答案：【8.8Gbps】11、【單選題】WhichiswrongamongthefollowingdescriptionsofthesimilaritiesamongCSMA/CD,TokenBusandTokenRing本題答案：【ThearchitecturefollowstheTCP/IPhierarchymodel】12、【單選題】WhichiswrongamongthefollowingdescriptionsofTokenBus本題答案：【Tokenisadataframewithaspecialstructure】13、【單選題】WhichiswrongamongthefollowingdescriptionsofTokenRing本題答案：【Thedataintheringistransmittedaroundtheringstationalongonedirection】14、【單選題】Whichiswrongamongthefollowingdescriptionsofthefourmajorprotocolsofmediaaccessconnection本題答案：【IEEE802.15definesthestandardsofaccess-controlsublayerandthephysicallayerforWAN】15、【單選題】Whichiswrongamongthefollowingdescriptionsofconflictdetection本題答案：【ThevalueofconflictwindowisequaltoD/V】16、【單選題】Whichiswrongamongthefollowingdescriptionsoftheframest