1、软件水平考试中级网络工程师上午基础知识（计算机专业英语）历年真题试卷精选 1 及答案解析(总分：60.00，做题时间：90 分钟)一、选择题(总题数：6，分数：60.00)1.选择题（）下列各题 A、B、C、D 四个选项中，只有一个选项是正确的，请将此选项涂写在答题卡相应位置上，答在试卷上不得分。（分数：10.00）_Although a given waveform may contain frequencies over a very broad rangeas a practical matter any transmission system will be able to accom
2、modate only a limited band of(71)This，in turn，limits the data rate that can be carried on the transmission (72)A square wave has an infinite number of frequency components and hence an infinite (73)However，the peak amplitude of the kth frequency component，kf，is only 1k，so most of the (74)in this wav
3、eform is in the first few frequency componentsIn general，any digital waveform will have(75)bandwidthIf we attempt to transmit this waveform as a signal over any medium，the transmission system will limit the bandwidth that can be transmitted.(2010 年上半年试题)（分数：10.00）(1).(71)（分数：2.00）A.frequenciesB.conn
4、ectionsC.diagramsD.resources(2).(72)（分数：2.00）A.proceduresB.functionC.routeD.medium(3).(73)（分数：2.00）A.sourceB.bandwidthC.energyD.cost(4).(74)（分数：2.00）A.frequencyB.energyC.amplitudeD.phase(5).(75)（分数：2.00）A.smallB.1imitedC.infiniteD.finiteRouting protocols use different techniques for assigning(1)to i
5、ndividual networkFurther，each routing protocol forms a metric aggregation in a different wayMost routing protocols can use multiple paths if the paths has an equal(2)Some routing protocols can even use multiple paths when paths have an unequal costIn either case，load(3)can improve overall allocation
6、 of network bandwidthWhen multiple paths are used，there are several ways to distribute the packetsThe two most common mechanisms are perpacket load balancing and perdestination load balancingPerpacket load balancing distributes the(4)across the possible routes in a manner proportional to the route m
7、etricsPer-destination load balancing distributes packets across the possible routes based on(5)(2009 年下半年试题)（分数：10.00）(1).(1)（分数：2.00）A.callsB.metricsC.1inksD.destinations(2).(2)（分数：2.00）A.userB.distanceC.entityD.cost(3).(3)（分数：2.00）A.bracketingB.balancingC.downloadingD.transmitting(4).(4)（分数：2.00）A
8、destinationsB.resourcesC.packetsD.sources(5).(5)（分数：2.00）A.destinationsB.resourcesC.packetsD.sourcesThe Border Gateway Protocol(BGP)is an interautonomous system (6)protocolThe primary function of a BGP speaking system is to exchange network(7)information with other BGP systemThis network reachabili
9、ty information includes information on the list of Autonomous System(Ass)that reachability information traversesBGP-4 provides a new set of mechanisms for supporting(8)interdomain routingThese mechanisms include support for advertising an IP (9)and eliminate the concept of network class within BGPBG
10、P 一 4 also introduces mechanisms that allow aggregation of routes，including (10)of AS pathsThese changes provide support for the proposed supemetting scheme(2009 年上半年试题)（分数：10.00）(1).(6)（分数：2.00）A.connectingB.resolvingC.routingD.supemettting(2).(7)（分数：2.00）A.secubilityB.reachabilityC.capabilityD.rel
11、iability(3).(8)（分数：2.00）A.answerlessB.connectionlessC.confirmlessD.classless(4).(9)（分数：2.00）A.prefixB.suffixC.infixD.reflex(5).(10)（分数：2.00）A.reservationB.relationC.aggregationD.connectionThe usual way to ensure reliable delivery is to provide the(11)with some feedback about what is happening at the
12、 other end of the lineTypically，the protocol calls for the receiver to send back special (12)flame bearing positive or negative (13)about the incoming flamesIf the sender receives a positiveAcknowledgement about a flame，it knows the flame has arrived safelyOn the other hand，a negative acknowledgemen
13、t means that something has gone wrong，and the frame must be transmitted againAn additional complication comes from the possibility that hardware troubles may cause a flame to(14)completelyIn this case，the receiver will not react at all，since it has no any reason to reactIt should be clear that a pro
14、tocol in which the sender transmits a frame and then waits for an acknowledgement，positive or negative，will hang forever if a flame is ever lost due to，for example，(15)handware(2008 年下半年试题)（分数：10.00）(1).(11)（分数：2.00）A.receiverB.controilerC.senderD.customer(2).(12)（分数：2.00）A.dateB.controlC.requestD.s
15、ession(3).(13)（分数：2.00）A.applicationB.connectionC.streamD.acknowledgement(4).(14)（分数：2.00）A.vanishB.varyC.appearD.incline(5).(15)（分数：2.00）A.actingB.workingC.malfunctioningD.functioningWLANs are increasingly popular because they enable costeffective connections among people and applications that were
16、 not possible in the pastFor example，WLANbased applications can enable finegrained management of supply(16)t0 improve their efficiency and reduce(17) WLANs can also enable entirely new business processesTo cite but one example，hospitals are using WLANenabled pointof-care(18)to reduce errors and impr
17、ove overall patient careWLAN management solutions provide a variety of other benefits that can be substantial but difficult to measureFor example，they can protect corporate date by preventing (19)throuth rogue access pointsThey can improve overall network management by integrating with customersexis
18、ting systemsFortunately，it isnt necessary to measure these benefits to j ustify investing in WLAN management solutions，which can quickly pay for themselves simply by minimizing time-(20)deployment and administrative chores(2008 年上半年试题)（分数：10.00）(1).(16)（分数：2.00）A.customB.serverC.chainsD.chances(2).(
19、17)（分数：2.00）A.overheadB.connectionC.supplyD.effect(3).(18)（分数：2.00）A.transportationsB.applicationsC.connectionsD.translations(4).(19)（分数：2.00）A.integrationB.interestC.instructionD.intrusion(5).(20)（分数：2.00）A.capableB.consumingC.effectiveD.connected软件水平考试中级网络工程师上午基础知识（计算机专业英语）历年真题试卷精选 1 答案解析(总分：60.00
20、做题时间：90 分钟)一、选择题(总题数：6，分数：60.00)1.选择题（）下列各题 A、B、C、D 四个选项中，只有一个选项是正确的，请将此选项涂写在答题卡相应位置上，答在试卷上不得分。（分数：10.00）_解析：Although a given waveform may contain frequencies over a very broad rangeas a practical matter any transmission system will be able to accommodate only a limited band of(71)This，in turn，limi
21、ts the data rate that can be carried on the transmission (72)A square wave has an infinite number of frequency components and hence an infinite (73)However，the peak amplitude of the kth frequency component，kf，is only 1k，so most of the (74)in this waveform is in the first few frequency componentsIn g
22、eneral，any digital waveform will have(75)bandwidthIf we attempt to transmit this waveform as a signal over any medium，the transmission system will limit the bandwidth that can be transmitted.(2010 年上半年试题)（分数：10.00）(1).(71)（分数：2.00）A.frequencies B.connectionsC.diagramsD.resources解析：(2).(72)（分数：2.00）A
23、proceduresB.functionC.routeD.medium 解析：(3).(73)（分数：2.00）A.sourceB.bandwidth C.energyD.cost解析：(4).(74)（分数：2.00）A.frequencyB.energy C.amplitudeD.phase解析：(5).(75)（分数：2.00）A.smallB.1imitedC.infinite D.finite解析：解析：译文：虽然一个给定的波形包含了很宽的频率范围，但任何实际的传输系统只能通过有限的频率。这样，就限制了传输介质可以承载的数据速率。一个方波包含了无限多的频率成分，因而也具有无限的带宽
24、然而，第 k 个频率成分的峰值幅度 k f 只是 1k，所以波形的大部分能量只是包含在前面的少数频率成分中。一般来说，任何数字波形都有无限带宽。如果我们试图在某种介质上传输这种波形信号，则传输系统实际上会限制可以发送的带宽。Routing protocols use different techniques for assigning(1)to individual networkFurther，each routing protocol forms a metric aggregation in a different wayMost routing protocols can use m
25、ultiple paths if the paths has an equal(2)Some routing protocols can even use multiple paths when paths have an unequal costIn either case，load(3)can improve overall allocation of network bandwidthWhen multiple paths are used，there are several ways to distribute the packetsThe two most common mechan
26、isms are perpacket load balancing and perdestination load balancingPerpacket load balancing distributes the(4)across the possible routes in a manner proportional to the route metricsPer-destination load balancing distributes packets across the possible routes based on(5)(2009 年下半年试题)（分数：10.00）(1).(1
27、)（分数：2.00）A.callsB.metrics C.1inksD.destinations解析：(2).(2)（分数：2.00）A.userB.distanceC.entityD.cost 解析：(3).(3)（分数：2.00）A.bracketingB.balancing C.downloadingD.transmitting解析：(4).(4)（分数：2.00）A.destinationsB.resourcesC.packets D.sources解析：(5).(5)（分数：2.00）A.destinations B.resourcesC.packetsD.sources解析：解析：
28、译文：路由协议使用不同的技术来给独立的网络标记度量值。此外，每种路由协议以不同的形式形成度量聚集。如果路径有一个平等的成本，大多数路由协议可以使用多条路径。即使路径有一个不平等的成本，一些路由协议也可以使用多条路径。在任何情况下，负载均衡可以提高整体的网络带宽分配。当使用多条路径时，有几种方法分发数据包。最常见的两种机制是每个包负载平衡和按目的地负载平衡。每包负载均衡的方式分发数据包的速率与路由度量值成比例；按目的地负载平衡分发数据包是以目的地为依据的。The Border Gateway Protocol(BGP)is an interautonomous system (6)protoco
29、lThe primary function of a BGP speaking system is to exchange network(7)information with other BGP systemThis network reachability information includes information on the list of Autonomous System(Ass)that reachability information traversesBGP-4 provides a new set of mechanisms for supporting(8)inte
30、rdomain routingThese mechanisms include support for advertising an IP (9)and eliminate the concept of network class within BGPBGP 一 4 also introduces mechanisms that allow aggregation of routes，including (10)of AS pathsThese changes provide support for the proposed supemetting scheme(2009 年上半年试题)（分数
31、10.00）(1).(6)（分数：2.00）A.connectingB.resolvingC.routing D.supemettting解析：(2).(7)（分数：2.00）A.secubilityB.reachability C.capabilityD.reliability解析：(3).(8)（分数：2.00）A.answerlessB.connectionlessC.confirmlessD.classless 解析：(4).(9)（分数：2.00）A.prefix B.suffixC.infixD.reflex解析：(5).(10)（分数：2.00）A.reservationB.r
32、elationC.aggregation D.connection解析：解析：译文：边界网关协议(BGP)是一种自治系统间的路由协议。BGP 发言系统的主要功能是与其他 BGP 系统交换可达性信息。网络的可达性信息就是要到达某个网络所经过的一系列的自治系统。BGP 一4 提供了一套全新的机制来支持无类域间路由。这些机制支持广播 IP 地址前缀，去除了网络分类的概念。BGP-4 还引入了允许路由聚合的机制，包括自知系统之间的路径聚合。这些变化都为提出的超网方案提供了支持。The usual way to ensure reliable delivery is to provide the(11)
33、with some feedback about what is happening at the other end of the lineTypically，the protocol calls for the receiver to send back special (12)flame bearing positive or negative (13)about the incoming flamesIf the sender receives a positiveAcknowledgement about a flame，it knows the flame has arrived
34、safelyOn the other hand，a negative acknowledgement means that something has gone wrong，and the frame must be transmitted againAn additional complication comes from the possibility that hardware troubles may cause a flame to(14)completelyIn this case，the receiver will not react at all，since it has no
35、 any reason to reactIt should be clear that a protocol in which the sender transmits a frame and then waits for an acknowledgement，positive or negative，will hang forever if a flame is ever lost due to，for example，(15)handware(2008 年下半年试题)（分数：10.00）(1).(11)（分数：2.00）A.receiverB.controilerC.sender D.cu
36、stomer解析：(2).(12)（分数：2.00）A.dateB.control C.requestD.session解析：(3).(13)（分数：2.00）A.applicationB.connectionC.streamD.acknowledgement 解析：(4).(14)（分数：2.00）A.vanish B.varyC.appearD.incline解析：(5).(15)（分数：2.00）A.actingB.workingC.malfunctioning D.functioning解析：解析：译文：保证可靠提交的常用方法是向发送端提供一些反馈信息，使它知道在线路的另一端发生了什么
37、情况。典型的情况是：协议要求接收端回送一个承载有关输入帧的肯定或否定应答的特殊控制帧。如果发送端收到了有关帧的肯定应答，它就知道发送的帧已经安全到达。另外，否定应答则意味着出现了某种错误，应该重新发送出错的帧。还有一些复杂的情况可能发生，硬件故障可能引起帧完全消失。在这种情况下，接收端完全没有反应，因为它根本无法反应。显然，如果一个帧由于硬件失效而丢失了，那么这样的协议发送端发出一个帧然后等待肯定或否定应答，就会被永远地挂起了。WLANs are increasingly popular because they enable costeffective connections among p
38、eople and applications that were not possible in the pastFor example，WLANbased applications can enable finegrained management of supply(16)t0 improve their efficiency and reduce(17) WLANs can also enable entirely new business processesTo cite but one example，hospitals are using WLANenabled pointof-c
39、are(18)to reduce errors and improve overall patient careWLAN management solutions provide a variety of other benefits that can be substantial but difficult to measureFor example，they can protect corporate date by preventing (19)throuth rogue access pointsThey can improve overall network management b
40、y integrating with customersexisting systemsFortunately，it isnt necessary to measure these benefits to j ustify investing in WLAN management solutions，which can quickly pay for themselves simply by minimizing time-(20)deployment and administrative chores(2008 年上半年试题)（分数：10.00）(1).(16)（分数：2.00）A.cust
41、omB.serverC.chains D.chances解析：(2).(17)（分数：2.00）A.overhead B.connectionC.supplyD.effect解析：(3).(18)（分数：2.00）A.transportationsB.applications C.connectionsD.translations解析：(4).(19)（分数：2.00）A.integrationB.interestC.instructionD.intrusion 解析：(5).(20)（分数：2.00）A.capableB.consuming C.effectiveD.connected解析：
42、解析：译文：无线局域网(WLAN)日益普及起来，这是因为它能够在用户和应用之间有效地建立连接，这在过去是很难做到的。例如，基于 WLAN 的应用可以对供应链进行细粒度的管理，从而改进效率，减少开销。WLAN 也可以创造全新的商业过程。仅举出其中的一个例子，医院使用基于 WLAN 的护理点应用来减少差错，全面改进病员护理。WLAN 管理解决方案提供的各种实质上的好处是很难度量的。例如，它可以保护公司的数据，防止恶意的访问。它可以全面地改进网络管理，并集成到用户现有的系统中。幸好，我们无须量化这些收益来证明 WLAN 管理解决方案的合理性，因为它能很快地补偿由于部署这些应用和管理事务而付出的时间开销。
