計算機網(wǎng)絡(luò)英文題庫

1、Chapter 5 The Link Layer and Local Area Network1A ( ) protocol is used to move a datagram over an individual link.Aapplication-layerBtransport-layerCnetwork-layerDlink-layer2The units of data exchanged by a link-layer protocol are called ( ).AdatagramsBframesCsegments Dmessages3Which of the followin

2、g protocols is not a link-layer protocol? ( )AEthernetBPPPCHDLCDIP4In the following four descriptions, which one is not correct? ( )Alink-layer protocol has the node-to-node job of moving network-layer datagrams over a single link in the path.BThe services provided by the link-layer protocols may be

3、 different.CA datagram must be handled by the same link-layer protocols on the different links in the path.DThe actions taken by a link-layer protocol when sending and receiving frames include error detection, flow control and random access.5Which of the following services can not offered by a link-

4、layer protocol? ( )Acongestion controlBLink AccessCError controlDFraming6( ) protocol serves to coordinate the frame transmissions of the many nodes when multiple nodes share a single broadcast link.AARPBMACCICMPDDNS7In the following four descriptions about the adapter, which one is not correct? ( )

5、AThe adapter is also called as NIC.BThe adapter is a semi-autonomous unit.半自動CThe main components of an adapter are bus interface and the link interface.DThe adapter can provide all the link-layer services.8Consider CRC error checking approach, the four bit generator G is 1011, and suppose that the

6、data D is , then the value of R is( ).A 010 9In the following four descriptions about random access protocol, which one is not correct? ( )A In slotted ALOHA, nodes can transmit at random time.B In pure ALOHA, if a frame experiences a collision, the node will immediately retransmit it with probabili

7、ty p.C The maximum efficiency of a slotted ALOHA is higher than a pure ALOHA.D In CSMA/CD, one node listens to the channel before transmitting.10In the following descriptions about MAC address, which one is not correct? ( )A The MAC address is the address of one nodes adapter.B No two adapters have

8、the same MAC address.C The MAC address doesnt change no matter where the adapter goes.D MAC address has a hierarchical structure.11The ARP protocol can translate ( ) into ( ). ( )A host name, IP address B host name, MAC addressC IP address, MAC address Dbroadcast address, IP address12The value of Pr

9、eamble field in Ethernet frame structure is ( )A B C D 13There are four steps in DHCP, the DHCP server can complete ( ).ADHCP server discovery BDHCP server offersCDHCP request DDHCP response14In CSMA/CD, the adapter waits some time and then returns to sensing the channel. In the following four times

10、, which one is impossible? ( )A0 bit times B512 bit times C1024 bit times D1028 bit times15The most common Ethernet technologies are 10BaseT and 100BaseT. “10” and “100” indicate( ).Athe maximum length between two adaptersBthe minimum length between two adaptersCthe transmission rate of the channelD

11、the transmission rate of the node16The principal components of PPP include but not( ).Aframing Bphysical-control protocol Clink-layer protocol Dnetwork-layer protocol17In the following four options, which service can not be provided by switch? ( )Afiltering Bself-learningCforwarding Doptimal routing

12、18In the following four services, which one was not be required in PPP? ( )Apacket framing Berror detectionCerror correction D multiple types of link19The ability to determine the interfaces to which a frame should be directed, and then directing the frame to those interfaces is( ).A filtering B for

13、wardingC self-learning D optimal routing20In ( ) transmission(s), the nodes at both ends of a link may transmit packets at the same time.Afull-duplex Bhalf-duplexCsingle-duplexDboth full-duplex and half-duplex21Consider the data D is , if use even parity checking approach, the parity bit is( ), if u

14、se odd parity checking approach, the parity bit is( ). ( ) A0 1B0 0C1 1D1 022In the following four descriptions about parity checks, which one is correct? ( )ASingle-bit parity can detect all errors.BSingle-bit parity can correct one errors.CTwo-dimensional parity not only can detect a single bit er

15、ror, but also can correct that error.DTwo-dimensional parity not only can detect any combination of two errors, but also can correct them.23MAC address is ( ) bits long.A32 B48 C128 D64/24Wireless LAN using protocol ( ).AIEEE 802.3BIEEE 802.4CIEEE 802.5DIEEE 802.1125The following protocols are belon

16、ging to multiple access protocols except for ( ).Achannel partitioning protocols信道劃分協(xié)議Brouting protocolsCrandom access protocolsDtaking-turns protocols26Which of the following is not belonging to channel partitioning protocols? ( )ACSMABFDMCCDMADTDM27In the following four descriptions about CSMA/CD,

17、 which one is not correct? ( )AA node listens to the channel before transmitting.BIf someone else begins talking at the same time, stop talking.CA transmitting node listens to the channel while it is transmitting.DWith CSMA/CD, the collisions can be avoided completely.28( ) provides a mechanism for

18、nodes to translate IP addresses to link-layer address.AIPBARPCRARPDDNS29A MAC address is a ( )address.Aphysical-layerBapplication-layerClink-layerDnetwork-layer30Which of the following is correct? ( )ANo two adapters have the same MAC address.BMAC broadcast address is FF-FF-FF-FF-FF-FF.CA portable可移

19、植的computer with an Ethernet card always has the same MAC address, no matter where the computer goes. DAll of the above31In the following four descriptions, which one is not correct? ( )AARP resolves an IP address to a MAC address.BDNS resolves hostnames to IP addresses.CDNS resolves hostnames for ho

20、sts anywhere in the Internet.DARP resolves IP addresses for nodes anywhere in the Internet./In the LAN, ( )protocol dynamically assign IP addresses to hosts.ADNSBARPCDHCPDIP/33DHCP protocol is a four-step process: DHCP request. DHCP ACK. DHCP server discovery. DHCP server offer(s). The correct seque

21、nce is ( )ABCD34In the Ethernet frame structure, the CRC field is ( )bytes.A2B4C8D3235In the Ethernet frame structure, the Data field carries the ( ).AIP datagramBsegmentCframeDmessage36In the following four descriptions, which one is not correct? ( )AEthernet uses baseband transmission基帶傳輸.BAll of

22、the Ethernet technologies provide connection-oriented reliable service to the network layer.CThe Ethernet 10Base2 technology uses a thin coaxial cable for the bus總線使用細同軸電纜.DThe Ethernet 10BaseT technology uses a star topology.37Ethernets multiple access protocol is ( ).ACDMABCSMA/CDCslotted ALOHADto

23、ken-passing protocol38In the following four descriptions about CSMA/CD, which one is not correct? ( )AAn adapter may begin to transmit at any time.BAn adapter never transmits a frame when it senses that some other adapter is transmitting.CA transmitting adapter aborts中止 its transmission as soon as i

24、t detects that another adapter is also transmitting.DAn adapter retransmits when it detects a collision. 39Which of the following descriptions about CSMA/CD is correct? ( )ANo slots are used.BIt uses carrier sensing.CIt uses collision detection.DAll of the above.40The Ethernet 10BaseT technology use

25、s( )as its physical media.Afiber opticsBtwisted-pair copper wireCcoaxial cableDsatellite radio channel41For 10BaseT, the maximum length of the connection between an adapter and the hub is ( )meters.A100B200C500D1042A ( )is a physical-layer device that acts on individual bits rather than on frames.As

26、witchBhubCrouterDgateway43A hub is a ( )device that acts on individual bits rather than on frames.Aphysical-layerBlink-layerCnetwork-layerDransport-layer44A switch is a( )device that acts on frame.Aphysical-layerBlink-layerCnetwork-layerDtransport-layer45In the following four descriptions, which one

27、 is not correct? ( )ASwitches can interconnect different LAN technologies.BHubs can interconnect different LAN technologies.CThere is no limit to how large a LAN can be when switches are used to interconnect LAN segments.DThere is restriction on the maximum allowable number of nodes in a collision d

28、omain when hubs are used to interconnect LAN segments.46The ability to determine whether a frame should be forwarded to some interface or should just be dropped is ( ).A filtering B forwardingC self-learning D optimal routing47Which of the following devices is not a plug and play device? ( )AhubBrou

29、terCswitchDrepeater48Which of the following devices is not cut-through device? ( )AhubBrouterCswitchDrepeater49In the following four descriptions, which one is not correct? ( )ASwitches do not offer any protection against broadcast storms.BRouters provide firewall protection against layer-2 broadcas

30、t storms.CBoth switches and routers are plug and play devices.DA router is a layer-3 packet switch, a switch is a layer-2 packet switch.50Which device has the same collision domain? ( )沖突域AHub BSwitchCRouter DBridge51IEEE802.2 protocol belong to ( )layerAnetwork BMACCLLC Dphysical52IEEE802.11 protoc

31、ol defines ( )rules.AEthernet Bus Bwireless WANCwireless LANDToken Bus53In data link-layer, which protocol is used to share bandwidth? ( )ASMTPBICMP CARPDCSMA/CD54When two or more nodes on the LAN segments transmit at the same time, there will be a collision and all of the transmitting nodes well en

32、ter exponential back-off, that is all of the LAN segments belong to the same( ).Acollision domainBswitchCbridgeDhub55( )allows different nodes to transmit simultaneously同時地 and yet have their respective receivers correctly receive a senders encoded data bits.ACDMA BCSMA CCSMA/CD DCSMA/CA56Because th

33、ere are both network-layer addresses (for example, Internet IP addresses) and link-layer addresses (that is, LAN addresses), there is a need to translate between them. For the Internet, this is the job of ( ).ARIP BOSPF CARP DIP57PPP defines a special control escape byte, ( ). If the flag sequence,

34、appears anywhere in the frame, except in the flag field, PPP precedes that instance of the flag pattern with the control escape byte.AB 0x7DC D58The device ( ) can isolate隔離 collision domains for each of the LAN segment.AmodemBswitchChub DNIC59In the following four descriptions about PPP, which one

35、is not correct? ( )APPP is required to detect and correct errors.BPPP is not required to deliver frames to the link receiver in the same order in which they were sent by the link sender.CPPP need only operate over links that have a single sender and a single receiver.DPPP is not required to provide

36、flow control.60In the PPP data frame, the( ) field tells the PPP receivers the upper-layer protocol to which the received encapsulated data belongs.AflagBcontrolCprotocolDchecksum61PPPs link-control protocols (LCP) accomplish ( ).Ainitializing the PPP linkBmaintaining the PPP linkCtaking down the PP

37、P linkDall of the above62The PPP link always begins in the ( ) state and ends in the ( ) state. ( )Aopen, terminatingBopen, deadCdead, deadDdead, terminating63For( ) links that have a single sender at one end of the link and a single receiver at the other end of the link.Apoint-to-pointBbroadcastCmu

38、lticastDall of the above64With ( )transmission, the nodes at both ends of a link may transmit packets at the same time.Ahalf-duplexBfull-duplexCsimplex(單工)Dsynchronous65With ( ) transmission, a node can not both transmit and receive at the same time.Ahalf-duplexBfull-duplexCsimplex(單工)Dsynchronous66

39、Which of the following functions cant be implemented in the NIC? ( )Aencapsulation and decapsulationBerror detectionCmultiple access protocolDrouting67Which of the following four descriptions is wrong? ( )AThe bus interface of an adapter is responsible for communication with the adapters parent node

40、.BThe link interface of an adapter is responsible for implementing the link-layer protocol.CThe bus interface may provide error detection, random access functions.DThe main components of an adapter are the bus interface and the link interface.68For odd parity schemes, which of the following is corre

41、ct? ( )ABCD69( )divides time into time frames and further divides each time frame into N time slots.AFDMBTMDCCDMADCSMA/70With CDMA, each node is assigned a different ( )AcodeBtime slotCfrequencyDlink71Which of the following four descriptions about random access protocol is not correct? ( )AA transmi

42、ssion node transmits at the full rate of the channelBWhen a collision happens, each node involved in the collision retransmits at once.CBoth slotted ALOHA and CSMA/CD are random access protocols.DWith random access protocol, there may be empty slots.72PPP defines a special control escape byte . If t

43、he data is b1bb3b4b5, the value is( )after byte stuffing.Ab1bb3b4b5Bb1bb3b4b5Cb5b4bb2b1Db5b4bb2b173MAC address is in ( ) of the computer.ARAMBNICChard diskDcache74Which of the following is wrong? ( )AARP table is configured by a system administrator系統(tǒng)管理員安裝的BARP table is built automaticallyCARP table

44、 is dynamicDARP table maps IP addresses to MAC addresses75NIC works in ( )layer.AphysicalBlinkCnetworkDtransport/76In LAN, if UTP is used, the common connector is( ).AAUIBBNCCRJ-45DNNI/77The modems function(s) is(are) ( ).Atranslates digital signal into analog signalBtranslates analog signal into di

45、gital signalCboth translates analog signal into digital signal and translates digital signal into analog signalDtranslates one kind of digital signal into another digital signal78( )defines Token-Ring protocol.AIEEE 802.3BIEEE 802.4CIEEE 802.5DIEEE 802.279( )defines Token-Bus protocol.AIEEE 802.3BIEEE 802.4CIEEE 802.5DIEEE 802.280( ) defines CSMA/CD protocol.AIEEE 802.3BIEEE 802.4CIEEE 802.5DIEEE 802.281The computer network that concentrated in a geograph