计算机网络英文题库附答案chapter3解析.docx
- 文档编号:4145798
- 上传时间:2022-11-28
- 格式:DOCX
- 页数:21
- 大小:22.66KB
计算机网络英文题库附答案chapter3解析.docx
《计算机网络英文题库附答案chapter3解析.docx》由会员分享,可在线阅读,更多相关《计算机网络英文题库附答案chapter3解析.docx(21页珍藏版)》请在冰豆网上搜索。
计算机网络英文题库附答案chapter3解析
Chapter3TransportLayer
1.Atransport-layerprotocolprovidesforlogicalcommunicationbetween.
AApplicationprocesses
BHosts
CRouters
DEndsystems
2.Transport-layerprotocolsrunin.
AServers
BClients
CRouters
DEndsystems
3.Intransportlayer,thesendsidebreaksapplicationmessagesinto,passesto
networklayer.
AFrames
BSegments
CData-grams
Dbitstreams
4.Servicesprovidedbytransportlayerinclude.
AHTTPandFTP
BTCPandIP
CTCPandUDP
DSMTP
5.WhichofthefollowingservicesisnotprovidedbyTCP?
ADelayguaranteesandbandwidthguarantees
BReliabledatatransfersandflowcontrols
CCongestioncontrols
DIn-orderdatatransfers
6.Thesetwominimaltransport-layerservicesandaretheonlytwo
servicesthatUDPprovides!
Aprocess-to-processdatadelivery,errorchecking
Bcongestioncontrol,reliabledatatransfer
Cflowcontrol,congestioncontrol
DIn-orderdatatransfer,errorchecking
7.Portnumber'sscopeisto.
A0,1023
B0,65535
C0,127
D0,255
8.Theportnumbersrangingfromtoarecalledwe-lklnownportnumber
andarerestricted.
A0,1023
B0,65535
0,127
C
D0,255
9.UDPsocketidentifiedbytwocomponents,theyare.
AsourceIPaddressesandsourceportnumbers
BsourceIPaddressesanddestinationIPaddresses
CdestinationIPaddressanddestinationportnumbers
Ddestinationportnumbersandsourceportnumbers
10.TCPsocketidentifiedbya(an).
A1-tuple
B2-tuple
C3-tuple
D4-tuple
11.WhichofthefollowingapplicationsnormallyusesUDPservices?
ASMTP
BStreamingmultimedia
CFTP
DHTTP
12.Reliabledatatransferprotocoloveraperfectlyreliablechannelis.
Ardt1.0Brdt2.0Crdt3.0Drdt2.1
13.Reliabledatatransferprotocoloverachannelwithbiterrorsandpacketlossesis
Ardt1.0Brdt2.0Crdt3.0Drdt2.1
14.Whichofthefollowingaboutreliabledatatransferoverachannelwithbiterrorsisnotcorrect?
ARDT2.0:
assumingACKandNAKwillnotbecorrupted
BRDT2.1:
assumingACKandNAKcanbecorrupted
CRDT2.2:
onlyuseACK-s
DRDT2.2:
usebothACK-sandNAK-s
15.Whichofthefollowingprotocolsisnotpipeliningprotocols?
ATCPBrdt3.0
CGO-BACK-NDselectiverepeat
16.WhichofthefollowingisnotcorrectaboutGBNprotocol?
AOnlyusingACK-s
BUsingcumulativeACK-s
CReceiverdiscardsallou-tof-orderpackets
DItisnotpipelinedprotocol
17.WhichofthefollowingisnotcorrectaboutSRprotocol?
Areceiverindividuallyacknowledgesallcorrectlyreceivedpackets
BsenderonlyresendspacketsforwhichACKnotreceived
CItlimitssequencenumberofsentbutun-ACK-edpackets
DItisnotapipelinedprotocol
18.WhichofthefollowingaboutTCPconnectionisnotcorrect?
AItisabroadcastconnection
BItisapoint-to-pointconnection
Itisapipelinedconnection
C
DItisafullduplexconnection
19.TheSYNsegmentisusedfor.
ATCPconnectionsetup
BTCPflowcontrol
CTCPcongestioncontrol
DClosingaTCPconnection
20.TheFINsegmentisusedfor.
ATCPconnectionsetup
BTCPflowcontrol
CTCPcongestioncontrol
DClosingaTCPconnection
21.HowdoesTCPsenderperceivecongestion?
AThroughatimeoutevent
BThroughareceivingduplicateACK-seventCBothAandB
DEitherAorB
22.Extendinghost-to-hostdeliverytoprocessto-processdeliveryiscalled
transport-layerand
Amultiplexingandde-multiplexing
Bstoringandforwarding
Cforwardingandfiltering
Dswitchingandrouting
23.UDPisaservicewhileTCPisaconnectionorientedservice.
AConnectionless
BReliable
CConnection-oriented
Dln-order
24.TheUDPheaderhasonlyfourfields,theyare.
ASourceportnumber,destinationportnumber,lengthandchecksum
BSourceportnumber,destinationportnumber,sourceIPanddestinationIP
CsourceIP,destinationIP,sourceMACaddressanddestinationMACaddress
DsourceIP,destinationIP,sequeneenumberandACKsequeneenumber
25.Therearetwo16bitintegers:
1110011001100110,1101010101010101.Their
checksumis.
010*********
1011101110111100
111111*********1
1000000000000000
26.Themaximumamountofdatathatcanbegrabbedandplacedinasegmentislimitedbythe.
AMaximumsegmentsize(MSS)
BMTU
CChecksum
Sequeneenumber
D
27.TheMSSistypicallysetbyfirstdeterminingthelengthofthelargestlink-layer
framethatcanbesentbythelocalsendinghost-theso-called.
AMaximumtransmissionunit(MTU)
BMSS
CChecksum
DSequeneenumber
28.AFilesizeof500,000bytes,MSSequals1000bytes.Whenwewanttotransmit
thisfilewithTCP,thesequencenumberofthefirstsegmentis0,andthesequencenumberofthesecondsegmentis..
A1000
B999
C1001
D500000
29.BecauseTCPonlyacknowledgesbytesuptothefirstmissingbyteinthestream,
TCPissaidtoprovide.
ACumulativeacknowledgements
BSelectiveacknowledgements
C3duplicateACKs
DpositiveACKs
30.Provideda=0.125,currentvalueofEstimatedRTTis0.4s,SampleRTTis0.8s,
thenthenewvalueofEstimatedRTTiss.
A0.45
B0.6
C0.7
D0.8
31.ProvidedRcvBuffer=20丄astByteRcvd=20,LastByteRead=15,then
RcvWindow=.
A14
B15
C16
D10
32.TCPservicedoesnotprovide.
AReliabledatatransferBFlowcontrol
CDelayguaranteeDCongestioncontrol
33.TherearetwostatesinTCPcongestioncontrol,whichare.
Aslowstartandcongestionavoidance
Bsafestartandcongestionavoidance
Cslowstartandcongestionabandon
Dsafestartandcongestionabandon
34.Thetranspor-tlayerprotocolprovideslogicalcommunicationbetween,and
thenetwork-layerprotocolprovideslogicalcommunication.
Ahosts,processes
Bprocesses,hosts
threads,processesC
Dprocesses,threads
35.ToimplementthemulticastservicestheInternetemploystheprotocol.
AFTPBTCPCIGMPDUDP
36.Ifanapplicationdeveloperchoosesprotocol,thentheapplicationprocessis
almostdirectlytalkingwithIP.
AHTTP
BRIP
CCSMA/CD
DUDP
37.maintainsconnection-stateintheendsystems.Thisconnectionstate
includesreceiveandsendbuffers,congestio-ncontrolparameters,andsequenceandacknowledgmentnumberparameters.
AUDPBTCPCDNSDHTTP
38.ThehostthatinitiatesthesessionintheInternetislabeledas.
AserverBuseragentCclientDrouter
39.WithTCPthereisnobetweensendingandreceivingtranspo-lratyer
entities.
AflowcontrolBhandshaking
C.congestioncontrolDVCsetup
40.TheInternet'sservicehelpspreventtheInternetfromenteringastateof
gridlock.
AdatagramBcongestioncontrol
CslidingwindowDtimeoutevent
41.Connectionsetupatthetransportlayerinvolves.
AserverBonlythetwoendsystems
CclientDrouter
42.Alayerprotocolprovidesforlogicalcommunicationbetweenapplications.
Atransport
Bapplication
Cnetworking
DMAC
43.Instaticcongestionwindow,ifitsatisfiesW*S/R>RTT+S/R,theLatencyis
AW*S/R-(RTT+S/R)
B2RTT+O/R
C2RTT+O/R+(k-1)[W*S/R-(RTT+S/R)]
D2RTT+S/R
44.Thereceivesideoftransportlayerreassemblessegmentsintomessages,passestolayer.
AApplication
BNetworking
CPhysical
DMAC
45.Inthefollowingfouroptions,whichoneiscorrect?
AThevariationsintheSampleRTTaresmoothedoutinthecomputationoftheEstimatedRTT
BThetimeoutshouldbelessthantheconnection'sRTT
CSupposethatthelastSampleRTTinaTCPconnectionisequalto1sec.Thenthe
currentvalueofTimeoutlntervalwillnecessarilybe>1sec
DSupposethatthelastSampleRTTinaTCPconnectionisequalto1sec.ThenthecurrentvalueofTimeoutlntervalwillnecessarilybe<1sec
46.TheportnumberusedbyHTTPis.
A80
B25
C110
D53
47.TheportnumberusedbySMTPis.
A80
B25
C110
D53
48.Theportnumberusedbypop3is.
A80
B25
C110
D53
49.TheportnumberusedbyDNSis.
A80
B25
C110
D53
50.TheportnumberusedbyFTPis.
A20and21
B20
C21
D53
51.AUDPsocketidentifiedbyatuple(s).
A2
B4
C1
D3
52.ATCPsocketidentifiedbyatuple(s).
A2
B4
C1
D3
53.ATCPsocketdoesnotinclude.
SourceMACaddress
A
BSourceportnumber
CDestinationIPaddress
DDestinationportnumber
54.WhichoffollowingaboutUDPisnotcorrect.
AItisareliabledatatransferprotocol
BItisconnectionless
CnohandshakingbetweenUDPsender,receiver
Ditisabesteffortserviceprotocol
55.DNSusesservice.
ATCP
BUDP
CBothTCPandUDP
DNoneofabove
56.WhichoffollowingaboutUDPiscorrect?
AFinerapplication-levelcontroloverwhatdataissent,andwhen
BNoconnectionestablishment(whichcanadddelay),sonodelayforestablishaconnection
CNoconnectionstate(so,UDPcantypicallysupportmanyactiveclients)
DLargepacketheaderoverhead(1-6B)
57.Streamingmediausesaservicenormally.
ATCP
BUDP
CBothTCPandUDP
DNoneofabove
58.TheUDPheaderhasonlyfields.
A2
B4
C1
D3
59.WhichofthefollowingdoesnotincludedinUDPheader.
ASourceportnumber
BDestinationportnumber
CChecksum
DSequencenumber
60.Whichofthefollowingisnotapipeliningprotocol.
ARdt1.0
BGo-Back-N
CSelectiverepeat
DTCP
61.InthefollowingfourdescriptionsaboutMSSandMTU,whichoneisnotcorrect?
ATheMSSisthemaximumamountofapplication-layerdatainthesegmentBTheMSSisthemaximumsizeoftheTCPsegmentincludingheadersCTheMSSistypicallysetbyMTU
TheMTUmeansthelargestlink-layerframe
D
62.Thejobofgatheringdatachunks,encapsulatingeachdatachunkwithheaderinformationtocreatesegmentsandpassingthesegmentstothenetworkiscalled
Amultiplexing
Bde-multiplexi
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 计算机网络 英文 题库 答案 chapter3 解析
![提示](https://static.bdocx.com/images/bang_tan.gif)