計(jì)算機(jī)網(wǎng)絡(luò)與通信期末考試B答案

1、大學(xué)期考試試題（B）閉卷（200820W第2學(xué)期）課程號(hào)：課序號(hào)：07課程名稱：計(jì)算機(jī)網(wǎng)絡(luò)與通信任課教師:等成績：適用專業(yè)年級(jí)：06學(xué)生人數(shù)：印題份數(shù)：學(xué)號(hào)：姓名：考試須知四川大學(xué)學(xué)生參加由學(xué)校組織或由學(xué)校承辦的各級(jí)各類考試，必須嚴(yán)格執(zhí)行四川大學(xué)考試工作管理辦法和四川大學(xué)考場規(guī)則有考試違紀(jì)作弊行為的，一律按照四川大學(xué)學(xué)生考試違紀(jì)作弊處罰條例進(jìn)行處理。四川大學(xué)各級(jí)各類考試的監(jiān)考人員，必須嚴(yán)格執(zhí)行四川大學(xué)考試工作管理辦法、四川大學(xué)考場規(guī)則和四川大學(xué)監(jiān)考人員職責(zé)有違反學(xué)校有關(guān)規(guī)定的，嚴(yán)格按照四J11大學(xué)教學(xué)事故認(rèn)定及處理辦法進(jìn)行處理。第一題第二題第三題第四題第五題卜總分一、英譯漢（10分）ISPIN

2、TERT服務(wù)供應(yīng)商2.NIC網(wǎng)絡(luò)接口卡3.DNS域名服務(wù)系統(tǒng)4.MAC介質(zhì)接入控制5BGP邊界網(wǎng)關(guān)協(xié)議6.MSS最大數(shù)據(jù)段尺寸7.FTP文件傳輸協(xié)議8MPLS多協(xié)議標(biāo)簽交換9AS自治系統(tǒng)1O.packetswitching分組交換:、單項(xiàng)選擇題（每小題I.5分，共30分）Werefertothelink-layerpacketsasDC. datagrams D. framesA.messagesB.segmentsTheIPprotocolliesinCA.applicationlayerB.transportlayerC.networklayerD.linklayerAisaCircuit

3、-switchednetwork.A.TDMB.DatagramnetworkC.InternetD.virtualcircuitnetworkThepacketexperiencesaBdelayasitwaitstobetransmittedontothelink.A.processingdelayB.queuingdelayC.propagationdelayD.transmissiondelayDWhichthefollowingprotocolsdoesnotuseTCP/IPasitsunderlyingprotocols?A.SMTP;B.FTP;C.TELNET;D.TFTPW

4、hatisusedtospecifyplacementoftext,filesandobjectsthataretobetransferredfromthewebservertotheclient?BA.HTTPB.HTMLC.HDLCD.AlloftheabovebandwidthisdescribedinBA)BytespersecondB)BitspersecondC)megabitspermillisecondD)centimeters)_BIsaprotocolfortransferringafilefromonehosttoanotherhost.A. SMTP; B.FTP;C.

5、TCP;D. UDPInTCP/IPstack,thetransportlayers flow control mechanisBA)slowstartB)congestionavoidaneeC)threehand-shakingD)slidingwindowComparedwithrdt2.0,thenewserviceinrdt3.0istoimplementthereliabledatatransferoverthechannelwithBA)biterrorB)datalossC)datatransferdelayD)congestionICMPcontrolmessagesaret

6、ransferredinDdataunit.A)TCPB).UDPC).ARPD).IPThereliabledatadeliverybetweenendsystemsisprovidedintheClayerofTCP/IParchitecture.A)networklayerB)datalinklayerC)transportlayerD)sessionlayerWhatisthemainfunctionofthenetworklayer?AA.node-to-nodedelivery;B.process-to-processmessagedeliveryD.updati ng andsy

7、nchronization;maintenanceofroutingtablesB)B) D) 24 t perform functions.WhichIPaddressisineffectiveDA)1C)ifipaddressis6224,thensubnetprefixis_CA)0C).theoutputportofarouterdonA)thephysicallayerfunctionsB)thedatalinklayerfunctionsC)networkmanagementD)buffermanagement.therearetwobroadclassesofpacket-swi

8、tchednetworks:datagramnetworksandvirtual-circuitnetworks.datagramnetworksforwardpacketstheirswitchesuseBA)MACaddressesC)e-mailaddresses.asshowbelow,whichtechnologyisntechnongy.Cdigitalsubscriberlinefiber-coaxialcableIPaddressesD)virtual-circuitnumbersttypicalaccessnetworksB)hybridC)circuitswitchingD

9、)wirelessaccessWhichlayer-functionismostlyimplementedinanadapter(NICA_A)physicallayerandlinklayerB)networklayerandtransportlayerC)physicallayerandnetworklayerD)transportlayerandapplicationlayerAWhichdevicecantisolatethedepartmentalcollisiondomains.A)Hub;B)switch;C)router;D)AandB注：1試題字跡務(wù)必清晰，書寫工整。本題4頁

10、，本頁為第1頁2題間不留空，一般應(yīng)題卷分開教務(wù)處試題編號(hào)：3務(wù)必用A4紙打印三、填空題(每空1分，共20分?)_protocolsdefineformat,orderofmessagessentandreceivedamongnetworkentities,andactionstakenonmessagetransmission,receipt.Thetimerequiredtoexaminethepacketsheaderanddeterminewheretodirectthepacketispartoftheprocessingdelay.Anynetworkthatforwardspac

11、ketsaccordingtohostdestinationaddressesa_datagramnetwork.WithintheInternetthemostimportantdelaysthatpacketsufferedare_processingoutingdelay,queuingdelay,_propagation.delay,and_transmission,delay.5.Twoimportantnetwork-layerfunctioncanbeidentified:forwarding6.Aaddress,or.physiaddress,or_MACaddress.and

12、selectiverepeat8.10.AWebcachealsocalleda_proxyserver7.Twogenericformsofpipelinedreliabledatetransferprotocolsarego-Back-N11.SupposeausersittinginahomenetworkbehinchostrequestsaWebpageonsomeWebserverPleaseaccordingtheNATtranslationtableattheNATrouter.Fillindatagramthatinclude3345判斷題（每小題1分，t10分）DddrTh

13、etop-downorderoftheinternDestaddr=0.0.4addr=addr=TheinternetscohnectionlessservicemakesprovisionforflbwcontrolportnumbersaswellasIPaddresses(有IP缺端口號(hào)個(gè)扣0.5分)andcongestioncontrol(F)3.他ARPresponsesentwithinaframewithaspecificdestinationIPaddress(F)linklayeraddressislanaddress(t)heSocketistheprogrammingi

14、nterfacebetweentheapplicationlayerandtnetworklayer(F)Routinginvolvesallofanetwork(T)sroutersForwardingtableisconfiguredbybothIntraandInter-ASroutingalgorithm(N)esAnynetworkthatforwardspacketsaccordingtohostdestinationaddressisaVCnetwork(F)HTTPismainlyapushprotocolandSMTPismainlyapullprotocol(N)Theba

15、sicserviceoflinklayeristomoveanetwork-layerdatagramfromonenode(routerorhost)to本題4教務(wù)處anadjacentnode.(N)注：1試題字跡務(wù)必清晰，書寫工整。頁，本頁為第2頁2題間不留空，一般應(yīng)題卷分開試題編號(hào)：3務(wù)必用A4紙打印五、計(jì)算題(30points)considerthefollowingnetwork.Withtheindicatedlinkcosts,useDijkstrashortest-pathalgorithmtocomputetheshortestpathfromWtoallnetworkno

16、des.10分twStepND(x),p(x)D(V),p(v)D(U),p(u)D(y),p(y)D(t),p(t)D(s),p(s)1W3,w1,w4,woooooo2wv3,w2,v4,v8,voo3wvu3,w4,v5,u7,u4wvux4,v5,u7,u5wvuxy5,u7,u6wvuxyt6,t7wvuxyts最短路徑：WXWVWVYWVUWVUTWVUTSSuppose,theISPhavebeenallocatedtheaddressblock/24,nowiftheISPwantdivideitsaddressblockinto6equal-sizedsubnetaddres

17、sblocks,andeachsubnetcouldinclude28hosts.PleaseutilizeCIDRizedaddresses,determinethelengthofsubnetportionofaddress.(namely,howmanybitsshouldbeextend?(2points)Pleasewriteoutthesubnet1#snetworkprefix(2分)andsubnetmask.(2分)Pleasewriteoutthesubnet#sbroadcastaddress.(分)4) Please write out the sub net #s range of hostaddress. (2 分)注：1試題字跡務(wù)必清晰，