计算机网络英文题库附答案chapter1

1、Chapter 1 Computer Networks and the In ternetn etworks use VC. nu mbers to forward packets toward their1 . The ( ) is a worldwide computer network, that is, a network erconnectsmillions of computingdevices throughout the world.PPt3Apublic In ter netBIntranetCswitch netDtelevisi on

2、 net2 . Which kind of media is not a guided media?()Atwisted-pair copper wireBa coaxial cableCfiber opticsD digital satellite cha nnel3 . Which kind of media is a guided media?()Ageostatio narysatelliteBlow-altitude satelliteCfiber opticsDwireless LAND datagram n etworks use VC. nu mbers and virtual

3、-circuit n etworks use dest in ati on addresses to forward packets toward their dest in ati on.9 . In the following options, which one is not a guided media?()Atwisted-pair wireBfiber opticsCcoaxial cableDsatellite10 . Processing delay does not include the time to ().Aexamine the packet s headerBwai

4、t to tra nsmit the packet ontothelinkCdeterm ine where to direct the packetD check bit-error in the packet11 . In the followi ng four descripti ons, which one is correct?()AThe traffic in te nsity must be greater tha n 1.BThe fracti on of lost packets in creases as the traffic inten sitydecreases.).

5、C If the traffic in te nsity is close to zero, the average queu ing delay 4 will be close to zero. A FramesThe un its of data excha nged by a lin k-layer protocol are called (DIf the traffic inten sity is close to one, the average queu ing delay BSegme ntswill be close to one. C Datagrams12 . The In

6、ternet s network layer is responsible for moving network-layer D bit streamspackets known as () from one host to another. 5. Which of the following option belongs to the circuit-switched networks?Aframe ()Bdatagram AFDMCsegme nt BTDMDmessage CVC networks13 .The protocols of various layers are called

7、 ().Dboth A and BA the protocol stack 6 . ( )makes sure that neither side of a connection overwhelmsthe otherB TCP/IPside by sending too many packets too fast.AReliable datatran sferBFlow con trolCCon gestio n con trolDHan dshak ingprocedureCISPDn etwork protocol14 . There are two classes of packet-

8、switched networks:(virtual-circuit n etworks.)n etworks andAdatagramBcircuit-switched7 . ( ) means that the switchmust receive the entire packet before it canbeg in to tran smit the first bit of the packet onto the outbo und link.C televisi on AStore-a nd-forward tra nsmissi onB FDMCEn d-to-e nd con

9、n ecti onDTDM8 . Datagram networks and virtual-circuit networks differ in that ().Dteleph one15 . Access networks can be loosely classified into three categories:reside ntial access, compa ny access and () access.A cabledQuestion 16 17 CA datagram n etworks are circuit-switched n etworks, and virtua

10、l-circuit n etworks are packet-switched n etworks.B datagram n etworks are packet-switched n etworks, and virtual-circuit n etworks are circuit-switched n etworks.datagram n etworks use dest in atio n addresses and virtual-circuitLa / RRa / LSuppose, a is the average rate at which packets arrive at

11、the queue, R is the transmission rate, and all packets consist of L bits, then the traffic inten sity is ( 16 ), and it should no greater tha n ( 17 ).16 . A LR / aBCD17. ABD-1B protocol 18 . In the Intern et, the equivale nt con cept to end systems is ().CintranetAhostsDn etworkBserversCclie ntsAth

12、eformat of messages exchangedbetweentwoormore Dcom muni cati ng en tities 19. In the Intern et, end systems are conn ected together by (Btheorder of messages exchangedbetweentwoormore Acom muni cat ing en tities B coaxial cableD distributed applicati ons24 . The Internet provides two services to its

13、 distributed applications: aconn ecti onl ess un reliable service and () service.Aflow con trolBconn ecti on-orie nted reliableCcon gesti on con trolDTCP25 . It defines the format and the order of messages exchanged between twoor more com muni cat ing en tities, as well as the acti ons take n on the

14、 tra nsmissi on an d/or receipt of a message or other eve nt. The sentence describes ().AIn ternet26 . In the following options, which does not define in protocol?()routers).copper wireC the acti ons take n on the tran smissi on of a message or other eve ntCcom muni catio n linksfiber optics信号D the

15、transmission signals are digital signals or analog signals模拟 D20 . End systems access to the Internet through its ().27 . In the follow ing opti ons, which is defi ned in protocol? () A modemsA the acti ons take n on the tra nsmissi on an d/or receipt of a message orBprotocolsother eve ntCISPB the o

16、bjects excha nged betwee n com muni cati ng en tities DsocketsC the content in the excha nged messages21 . End systems, packet switches, and other pieces of the In ter net, run ()D the locati on of the hosts that con trol the sending and receiv ing of in formati on with in the28 . In the following o

17、ptions, which does not belong to the network edge?In ter net.()AprogramsAend systemsBprocessesBroutersCapplicati onsCclie ntsDprotocolsDservers22 . There are many private n etworks, such as many corporate and29 . In the following options, which belongs to the network core?()A end systemsgover nment

18、n etworks, whose hosts cannot excha nge messages with hosts outside of the private n etwork. These private n etworks are ofte n referred to as ().Ain ternets'Cin tra netsA reliable data tran sferBguara ntee of the tran smissi on timeBLAN30 . In the followi ng opti ons, which is not the bun dled

19、with the In ternet conn ecti on-orie nted service? () D WAN23 . The internet allows () running on its end systems to excha nge datawith each other.C flow controlAclients applications'k'k'kB server applicatio ns31 . An application can rely on the connection to deliver all of its data CP2P

20、 applicatio nswithout error and in the proper order. The sentence describes ().Dcon gesti on-con trolAflow con trolCdata switch ingBcon gesti on-con trolDmessage switch ingCreliable data tran sfer40 . In ()n etworks, the resources n eeded along a path to provide forDconn ecti on-orie nted servicecom

21、 muni cati on betwee n the end system are reserved for the durati on持续 of the com muni cati on sessi on. 32. It makes sure that n either side of a conn ecti on overwhelms 淹没 压倒A packet-switchedB data-switchedC circuit-switchedthe other side by sending too many packets too fast. The sentence describe

22、s ().A flow con trolBcon gesti on-con trolCconn ecti on-orie nted serviceD reliable data tran sferD message-switched33 . It helps preve nt the In ter net from en teri ng a state of gridlock. When apacket switch becomes con gested, its buffers can overflow and packet loss can occur. The sentence desc

23、ribes ().Aflow con trolBcon gesti on-con trolCconn ecti on-orie ntedserviceDreliable data tran sfer41 . In () n etworks, the resources are not reserved; a sessi on 'messagesuse the resources on dema nd, and as a con seque nee, may have to wait for access to com muni cati on link.A packet-switche

24、dB data-switchedC circuit-switchedD message-switched42 . In a circuit-switched network, if each link has n circuits, for each linkused by the en d-to-e nd conn ecti on, the conn ecti on gets () of thelink ' bandwidth for the duration of the connection.A a fracti on 1/n34 . The In ter net ' c

25、onn ecti on-orie nted service has a n ame, it is ().A TCPB UDPC TCP/IPD IP35. In the followingoptions, which service does not be provided to anapplication by TCP?( )Areliable tran sportBflow con trolC video con fere ncingDcon gesti on con trol36 . The In ter net ' conn ecti onl ess service is called ().A TCPB UDPC TCP/IPD IP37 . In the following options, which does not use TCP?()A SMTPB internet teleph oneC FTPD HTTP38 . In the followi ng optio ns, which does not use UDP?()A Internet phoneBvideo con fere ncingCstreami ng multimed