大连交通大学《计算机网络》期末考试复习习题(精简版)

2022年大连交通大学计算机网络技术专业《计算机网络》科目期末试卷A（有答案）一、选择题1、假设OS1参考模型的应用层欲发送400B的数据（无拆分），除物理层和应用层之外，其他各层在封装PDU时均引入20B的额外开销，则应用层数据传输率约为（）。

A.80%B.83%C.87%D.91%2、比特的传播时延与链路带宽的关系是（）。

A.没有关系B.反比关系C.正比关系D.无法确定3、UDP数据报比IP数据报多提供了（）服务。

A.流量控制B.拥塞控制C.端口功能D.路由转发4、在一个网络中，最大TPDU尺寸为256B，最大的TPDU存活时间为20s，使用8位序列号，则每条连接的最大数据传输速率是（）。

A.16112bit/sB.26112bitsC.36112bi/sD.461l2bit/s5、以太网帧的最小长度是（）。

A.32B.64C.128D.2566、下列关于交换机的叙述中，正确的是（）A.以太网交换机本质上是一种多端口网桥B.通过交换机互连的一组工作站构成一个冲突域C.交换机每个端口所连网络构成一个独立的广播域D.以太网交换机可实现采用不同网络层协议的网络互连7、为了使模拟信号传输得更远，可以采用的设备是（）。

A.中继器B.放大器C.交换机D.路由器8、因特网上的数据交换方式是（）。

A.电路交换B.报文交换C.分组交换D.光交换9、下列关于单模光纤的描述中，正确的是（）A.单模光纤的成本比多模光纤的成本低B.单模光纤传输距离比多模光纤短C.光在单模光纤中通过内部反射来传播D.单模光纤的直径一般比多模光纤小10、通过"Internet信息服务（IIS）管理器”管理单元可以配置FTP服务器，若将控制端口设置为2222，则数据端口自动设置为（）。

A.20B.21C.2223D.222111、在TCP/IP协议簇中，应用层的各种服务是建立在传输层提供服务的基础上的。

下列协议组中（）需要使用传输层的TCP建立连接。

2022年大连交通大学公共课《大学计算机基础》期末试卷A(有答案）一、单项选择题1、下列数据中，最小数是（）A.(10111100)2B. (162)sC. (264)10D. (CD)162、下面关于二进制的运算中，错误的是（）A．10+01=11 B.11+01=111 C.11-01=10 D.10-01=013、与二进制数0111对应的十进制数是（）A.5B.6C.7D.84、下面关于二进制的运算中，错误的是（）A．10+01=11 B.11+01=111 C.11-01=10 D.10-01=015、计算机病毒造成的危害是（）A.使磁盘发霉B.破坏计算机系统C.使计算机内存芯片损坏D.使计算机系统突然掉电6、目前，一张直径为12cm的单面单层DVD光盘存储容量一般可以达到（）A.650KBB.3.2GBC. 4.7GBD.6.5GB7、微型计算机硬件系统中最核心的部件是（）A. 显示器B. CPUD. I/O设备8、在Windows 7用户账户管理中，标准账户可以（）A.在本地计算机安装新软件和硬件B.使用本地计算机中的软件C.更改计算机安全设置D.创建高级用户9、在Windows 7中，显示3D桌面效果的快捷键是（）A.Windows+D 键B.Windows+P 键C.Windows+Tab 键D.Windows+Alt 键10、对于鼠标操作，下列叙述不正确的是（）A.双击速度可调B.可以双击C.可以三击D.左右键功能不可交换11、要移动Windows 7应用程序窗口，可用鼠标拖动窗口中的（）A.边框B.滚动条D.控制菜单12、在Windows 7资源管理器中，删除U盘中文件的操作是将文件（）A.放入回收站B.暂时保存到硬盘中C.从U盘中清除D.改名后保存在U盘中13、在Windows 7中，终止应用程序的正确方法是（）A.用鼠标双击该应用程序窗口左上角的控制菜单图标B.将应用程序窗口最小化成图标C.用鼠标双击应用程序窗口右上角的还原按钮D.用鼠标双击应用程序窗口中的标题栏14、在Word2010中，对已选中的浮于文字上方的图片位置向上微调应使用（）A "Alt+向上键"B"Ctrl+向上键"C"Esc+向上键"D"Shif+向上键"15、在Word 2010中，对同一个文档的两次不同的修订版本进行比较，应选择。

《计算机网络》期末考试试卷(A卷)试题答案一、填空题（每小题2分，共20分）DDCCD DBBBB二、填空题（每小题1分，共10分）1、拓扑结构；2、请求；3、网络接口层；4、分组交换；5、成帧与帧同步；6、广播；7、网络；8、路由选择；9、UDP、UDP；10、单向函数三、简答题（每小题4分，共20分）1、列出OSI参考模型和TCP/IP参考模型的主要相同点和不同点。

答：⑴相同点：①都基于分层协议，都有网络层、传输层和应用层；②传输服务都能提供可靠的端对端的字节流。

(2分)⑵不同点：①层的数目不同；②TCP/IP支持网络互连，OSI不支持网络互连；③TCP/IP网络层只提供无连接的服务，OSI中既有面向连接的服务，也有无连接的服务。

(2分)2、分析PPPoE协议过程。

答：PPPoE协议过程包括两个阶段，即：发现阶段和会话阶段。

(1分)发现阶段主要是选择访问集中器，确定所要建立的PPP会话标识符，同时获取对方点到点的连接信息。

典型的发现阶段分为4个步骤：⑴PPPoE活动发现启动PADI；⑵PPPoE活动发现响应PADO；⑶PPPoE活动发现请求PADR；⑷PPPoE活动发现确认PADS。

（2分）在完成了上述4个步骤之后，双方就可以进入会话阶段了。

PPPoE会话阶段执行标准的PPP过程。

（1分）3、说明CSMA/CD方法的基本工作原理。

答：CSMA/CD，即带碰撞检测的载波侦听多路访问协议，基本原理是：站点使用CSMA协议进行数据发送；（1分）在发送期间如果检测到碰撞，立即终止发送，并发出一个瞬间干扰信号，使所有的站点都知道发生了碰撞；（1分）在发出干扰信号后，等待一段随机时间，再重复上述过程。

（1分）因此，CSMA/CD的工作状态分为传输周期、竞争周期和空闲周期。

（1分）4、从多个角度比较虚电路和数据报这两种服务的优缺点。

答：数据报服务和虚电路服务是分组交换广域网向高层提供的两类服务，即无连接的网络服务和面向连接的网络服务的具体实现。

计算机网络期末复习资料（试题及答案）第一部分：选择题1. 在计算机网络中，ARQ是指（）。

A. 自动请求重传B. 自适应重传请求C. 自动重复请求D. 自适应重复请求答案：A2. 以下哪种协议属于面向连接的可靠传输协议？A. UDPB. TCPC. ICMPD. IP答案：B3. 数据链路层的主要功能是（）。

A. 封装和解封装B. 路由选择C. 差错控制D. 数据加密答案：A4. 网络拓扑结构中，所有节点通过一个公共的传输媒介连接在一起的是（）拓扑。

A. 总线型B. 星型C. 环型D. 网状型答案：A5. 在TCP/IP协议中，IP属于（）层。

A. 应用层B. 传输层C. 网络层D. 数据链路层答案：C第二部分：简答题1. 简述分组交换和电路交换的区别。

答：分组交换与电路交换是两种常见的数据交换技术。

电路交换是一种预先建立连接并一直保持连接状态的数据交换方式，占用资源较多，但传输稳定。

分组交换则将数据划分为较小的数据包进行传输，不需要预先建立连接，资源利用率较高，但传输过程中可能出现数据丢包或延迟等问题。

2. 简述TCP协议的传输过程。

答：TCP协议是一种面向连接的可靠传输协议。

在传输数据之前，发送方和接收方需要建立连接。

传输过程中，发送方将数据分割成较小的数据块，每个数据块被封装成TCP报文段。

发送方发送TCP报文段到接收方，接收方接收到报文段后进行确认，并按序组装数据。

如果发送方没有接收到确认信息，会进行重传。

传输完成后，发送方和接收方进行连接释放。

第三部分：应用题1. 假设一个局域网内有4台计算机，IP地址分别为192.168.1.1、192.168.1.2、192.168.1.3、192.168.1.4，子网掩码为255.255.255.0。

请问这4台计算机是否在同一个子网下？答：是的，因为这4台计算机的IP地址前三个字节相同，且子网掩码相同，所以它们在同一个子网下。

2. 自动重传请求（ARQ）是一种常用的差错控制技术，请简述ARQ的工作原理。

Chapter 4 The Network Layer1．What is the name of a network-layer packet?（）A.messageB.segmentC.datagramD.frame2．What are the two most important network-layer functions in a datagram network? （）A.forwarding & routingB.forwarding & filteringC.routing & detectingD.routing & checking3．When a packet arrives at a router’s input link, the router must move the packet to the appropriate output link, this action is called ____? （）A.ForwardingB.routingC.cut throughD.filtering4．The network layer must determine the path taken by packets as they flow from a sender to a receiver. This action is called____? （）A.ForwardingB.routingC.cut throughD.examine5．A router forwards a packet by examining the value of a field in the arriving packet’s header, and then using this value to index into the router’s forwarding table, this value is? （）A.destination IP addressB.source IP addressC.destination MAC addressD.source MAC address6．IP belongs to ____ layer? （）A.transportworkC.data linkD.physical7．Which layer provides host-to-host services? （）A.transportworkC.data linkD.physical8．Which layer provides a connection service called virtual-circuit networks and a connectionless service called datagram networks? （）A.transportworkC.data linkD.physical9．IPV4 has a ___ bit address? （）A.48B.16C.32D.6410．MAC address is ____ bits? （）A.48B.16C.32D.6411．The Internet’s network layer has three major component s, the first component is the IP protocol, the second component is the routing protocol, the final componentis____? （）A.forwardingB.address translationC.checkD.ICMP12．How many bits specify the IP protocol version in a datagram? （）A. 1 bitB. 2 bitsC. 4 bitsD.8 bits13．Most IPV4 datagram do not contain option field, how many bytes a header has in a typical IP datagram? （）A. 4 bytesB.8 bytesC.16 bytesD.20 bytes14．How many bits used in IP datagram express total length of the IP datagram? （）A. 4 bitsB.8 bitsC.16 bitsD.20 bits15．Data-grams are rarely larger than ____?（）A.1500 bytesB.65535 bytesC.500 bytesD.1024 bytes16．New version of IP----IPV6 does not allow fragment in ____?（）A.RouterB.HostC.Both of aboveD.None of above17．How does the TTL changed by one each time the datagram is processed by a router? （）A.decreaseB.increaseC.no changeD.always 018．Which layer protocol is indicated by the value of protocol field in IP datagram? （）A.applicationB.transportworkD.data link19．IP option is dropped in the ____ header. （）A.IPv6B.IPv4C.TCPD.UDP20．The data field in IP datagram can carry many types of data except ____. （）A.TCPB.UDPC.ICMPD.MAC21．ICMP is used for____?（）A.Reliable data transferB.Error reportingC.Flow controlD.Congestion control22．Suppose you receive an IP datagram from one link and check your forwarding table to determine the outgoing link, but this outgoing link has an MTU that is smaller than the length of IP datagram. Which technology will be used? （）A.resendB.discardC.fragmentD.none23．The designer of IPv4 decided to put the job of datagram reassembly in____.（）A.routerB.switchC.hubD.end system24．IP addressing assigns an address to 223.10.198.250/29, the network address for this network is____.（）A.223.10.198.248B.223.10.198.250C.223.10.198.0D.223.10.0.025．If all data-grams arriving at the router from WAN have the same destination IP address, then how does the router know the internal host to which it should forward a given datagram? The trick is to use ____ table at router, and include port numbers as well as IP address in the table entries. （）A.routingB.forwardingC.ARPD.NAT translation26．When running a Telnet, FTP, or HTTP session, you may have encountered an error message such as “Destination network un-reachable”, This message had its origin in ____. （）A.IGMPB.EGPC.ICMPD.BGP27．The well-known ping program sends an (a) ____ type 8 code 0 message to the specified host. The destination hosts seeing the echo request, send back a type 0 code0 ICMP echo reply. （）A.ICMPB.IGMPC.TCPD.UDP28．Tracer-out is implemented with ____ messages. （）A.IGMPB.TCPC.UDPD.ICMP29．The standard Tracer-out program actually sends sets of ____ packets with the same TTL. （）A.oneB.twoC.threeD.four30．IPv6 increases the size of the IP address from 32bit to ____ bit. （）A.64B.128C.256D.51231．How many bytes are there in header of IPv6? （）A.8B.20C.40D.3232．IPv6 does not allow for fragmentation and reassembly at inter-media ____. （）A.routersB.switchesC.end systemD.hubs33．From sender to receivers, all packets will take the same path, this is we use a ____ service. （）A.datagramB.VCC.circuitD.Ethernet34．____ means moving packets from router’s input port to appropriate router output port? （）A.forwardingB.filteringC.routingD.switching35．____ means determining route taken by packets from source to destination?（）A.forwardingB.filteringC.routingD.switching36．A router works in ____ layer? （）workingB.Data linkC.ApplicationD.Physical37．A switch works in ____ layer? （）workingB.Data linkC.ApplicationD.Physical38．Networking layer provides services between two ____.（）A.HostsB.ProcessesC.ApplicationsD.Machines39．Link layer provides services between two ____. （）A.HostsB.ProcessesC.ApplicationsD.Machines40．The internet’s network layer provides a single service----that is ____.（）A.Reliable data transferB.Flow controlC.Congestion controlD.Best-effort-service41．Datagram network provides network-layer____.（）A.connectionless serviceB.connection serviceC.both of aboveD.neither of A and B42．VC network provides network-layer ____. （）A.connectionless serviceB.connection serviceC.both of aboveD.neither of A and B43．In VC network, each packet carries ____. （）A.VC identifierB.destination host addressC.IP addressD.Mac address44．A VC consists of three part, this three parts do not include____. （）A.Path from source to destinationB.VC numbers, one number for each link along pathC.Entries in forwarding tables in routers along pathD.Destination address45.In ____ networking, a series of packet may follow different paths and may arrive out of order? （）A.DatagramB.VCC.TCPD.None of above46．The internet is a (an) ____ network? （）A.DatagramB.VCC.Both of aboveD.None of above47．The four components of a router do not include____? （）A.Input and output portsB.Switch fabricC.Routing processorD.Switching processor48．There are three kinds of switch fabric for a router normally, those three switchfabric do not includes____?（）A.Switching via memoryB.Switching via a busC.Switching via an Interconnection-NetworkD.Packet switching49．Which of the following protocol is used for error reporting? （）A.ICMPB.TCPC.IPD.UDP50．Which of the following is not a routing protocol? （）A.TCPB.RIPC.OSPFD.BGP51．IPV4 has a ___ bits address? （）A.32B.64C.16D.12852．IP address is identifier for ____. （）A.HostB.Router interfaceC.Both of aboveD.None of above53．“233.1.1.0/24”, where the /24 notation, sometimes known as a____. （）A.Subnet maskworking addressC.Host addressD.None of above54．Subnets with an 8-, ____-, and 24-bit subnet addresses were know as class A, B, and C networks respectively. （）A.9B.10C.12D.1655．IPV6 has a ___ bits address? （）A.32B.64C.16D.12856．____ means that IPv6 nodes also have a complete IPv4 implementation as well? （）A.Dual stackB.TunnelingC.Bridge connectionD.Forwarding57．____ means that IPv6 carried as payload in IPv4 data-gram among IPv4 routers? （）A.Dual stackB.TunnelingC.Bridge connectionD.Forwarding58．Typically a host is attached directly to one router, the ____ for the host. （）A.Default routerB.Source routerC.Destination routerD.Core router59．The default router of the source host is known as ____.（）A.Default routerB.Source routerC.Destination routerD.Core router60．The default router of the destination host is known as ____. （）A.Default routerB.Source routerC.Destination routerD.Core router61．A path between the source and destination that has beast cost is known as____. （）A.Least cost pathB.Shortest pathrgest cost pathD.None of above62．The path with the smallest number of links between the source and the destination is known as ____. （）A.Least cost pathB.Shortest pathrgest cost pathD.None of above63．Which of following about DV is not correct? （）A.IterativeB.SynchronousC.DistributedD.Self-terminating64．Which of the following is not intra-AS routing protocol? （）A.RIPB.OSPFC.IGRPD.BGP65．RIP is a kind of ____ algorithm. （）A.DVB.LSC.Both of aboveD.Neither of A and B66．OSPF is a kind of ____ algorithm. （）A.DVB.LSC.Both of aboveD.Neither of A and B67．The router in non-backbone areas and perform only intra-AS routing is known as ____. （）A.Internal routersB.Area border routersC.Backbone routersD.Boundary routers68．____“summarize” distances to nets in own area, advertise to other Area Border routers. （）A.Internal routersB.Area border routersC.Backbone routersD.Boundary routers69．____ runs OSPF routing limited to backbone. （）A.Internal routersB.Area border routersC.Backbone routersD.Boundary routers70．____ connect to other AS’s. （）A.Internal routersB.Area border routersC.Backbone routersD.Boundary routers71．Which of the following is an inter-autonomous system routing protocol? （）A.RIPB.OSPFC.IGRPD.BGP72．____means sending a packet to all other nodes in the network. （）A.BroadcastB.MulticastC.Any-castD.Uni-cast73．A ____ packet is delivered to only a subset of network nodes. （）A.BroadcastB.MulticastC.Any-castD.Uni-cast74．Means that the switch must receive the entire packet before it can begin to transmit the first bit of the packet onto the outbound link. （）A.store-and-forward transmissionB.FDMC.End-to-end connectionD.TDM75．Datagram networks and virtual-circuit networks differ in ____.（）A.Datagram networks are circuit-switched networks, and virtual-circuitnetworks are packet-switched networks.B.Datagram networks are packet-switched networks, and virtual-circuitnetworks are circuit-switched networks.C.Datagram networks use destination addresses and virtual-circuit networksuse VC. Numbers to forward packets toward their destination.D.Datagram networks use VC. Numbers and virtual-circuit networks usedestination addresses to forward packets toward their destination.76．The Internet’s network layer is responsible for moving network-layer packets known as ____ from one host to another. （）A.frameB.datagramC.segmentD.message77．The protocols of various layers are called ____. （）A.the protocol stackB.TCP/IPC.ISPwork protocol78．The two important network-layer functions are ____. （）A.multiplexing and de-multiplexingB.routing and forwardingC.lookup and forwardingD.routing and IP addressing79．The virtual circuit includes three identifiable phases but ____. （）A.setupB.data transferC.forwarding VC numbersD.teardown80．There are some ways to accomplish the switching in the router, which one is not included? （）A.switching via memoryB.switching via a busC.switching via hubD.switching via an interconnection81．In the router, the packet queues can form at ____.（）A.institutional cacheB.switch fabricC.input portD.routing processor82．In IPV4 datagram header, which field is to ensure that datagram do not circulate forever in the network? （）A.type of serviceB.time-to-liveC.header checksumD.version83．Suppose one IP datagram of 5,000 bytes (20 bytes of IP header) and it must be forwarded to a link with an MTU of 1,500 bytes, the offset and flag of the second fragment in header are ____. （）A.185, 0B.185, 1C.370, 1D.370,084．Given the IP address 202.96.104.8/20, its subnet address is ____. （）A.202.96.104.0B.202.96.96.0C.202.96.104.255D.202.96.111.25585．If the subnet mask is 255.255.240.0, then how many bits indicate the host address? （）A.20B.24C.12D.1686．In the following four fields, which is in IPV6 header but not in IPV4? （）A.source addressB.destination addressC.versionD.flow label87．One host is attached directly to one router, the router is ____.（）A.NAT routerB.gateway routerC.first-hop routerD.interval router88．The Internet’s network layer includes the following components but ____.（）A.IP protocolB.the Internet Message Control ProtocolC.Routing ProtocolD.Channel Partitioning Protocol89．In the following protocols, which one is inter-AS routing protocol? （）A.RIPB.OSPFC.BGPD.ICMP90．In the following four descriptions about autonomous system, which one is not correct? （）A.An autonomous system is a collection of routers under the sameadministrative and technical control.B.All routers in an autonomous system run the same routing protocol.C.The routing algorithm running within an autonomous system is called anintra-AS routing protocol.D.The routers that connect AS-s to each other are called default router.91．In the loop of the Dijkstra’s algorithm, for node x, add y to N’, and update the cost of y’s neighbor v, then D(v) is ____. （）A.c(x, v)B.min{D(v), D(x)+c(x, v)}C.min{D(v), D(y)+c(y, v)}D.c(y, v)92．Consider the data D is 01110010001, if use even parity checking approach, the parity bit is ( ), if use odd parity checking approach, the parity bit is ____. （）A.0, 0B.0, 1C.1, 0D.1, 193．The ability to determine the interfaces to which a frame should be directed, and then directing the frame to those interfaces is ____.（）A.filteringB.forwardingC.self-learningD.optimal routing94．Given that costs are assigned to various edge in the graph abstraction. In the following four descriptions, which one is not correct? （）A.The shortest path is the path with smallest number of links between thesource and destination.B.The least cost path is not always the shortest path.C.If all edges have same cost, the least cost path must be the shortest path.D.If all edges have various costs, the least cost path must not be the shortestpath.95．Given the IP address 202.96.104.8/20, its broadcast address is ____. （）A.202.96.104.0B.202.96.96.0C.202.96.104.255D.202.96.111.25596．If the subnet mask is 255.240.0.0, then how many bits indicate the host address? （）A.20B.12C.24D.1697．In IPV6 datagram header, the field Next-header is equivalent to the field ( ) in IPV4. （）A.upper-layer protocolB.time-to-liveC.header checksumD.version98．For one host, its source router is also called ____. （）A.NAT routerB.gateway routerC.first-hop routerD.interval router99．In the following four descriptions about link-state (LS) algorithm, which one is not correct? （）A.The LS algorithm must be aware of the cost of each link in the network.B.The LS algorithm is a decentralized algorithmC.The LS algorithm computes the least cost path between a source anddestination using complete global knowledge about the networkD.The calculation of LS algorithm can be run at one site or multiple sites 100．In the initialization of the Dijkstra’s algorithm, for node x, if y is not a neighbor of x, then D(y) is ____. （）A.0B. 1C.∞D.c(x, y)101．In DV algorithm, when one node updates its distance vector, it must ____.（）A.send the updated routing table to its neighborsB.send the updated routing table to all the nodes in the ASC.send the updated routing table at randomD.do nothing102．Now we had known IP address is 211.197.3.158/26, Please compute :(1). Network address?(2). Broadcast address?(3). How many hosts are there in the network?(4). Fist host IP address?(5). Last host IP address?103．For the given topology of the network, use Dijstra’s shortest path algorithm to compute the shortest path from A to all network nodes. Give a shortest path tree and node A’s routing table.104．The topology of a network shown as below. Using Link State routing algorithm to calculate the routing table in the node A. The vectors arrive to node C as bellow: B:( 4, 0, 8, 12, 6, 2 ); D:( 13, 10, 6, 0, 9, 10 ); E:( 7, 6, 3, 9, 0, 14 ). The delays measured from C to B, D, E are 4, 2, and 3 separately. Update router C ’s route table please.1 EABDCF12522153A B C DFE。

计算机网络期末试题及答案A卷填空题（每空 1 分.共 30 分）1、在计算机网络的定义中.一个计算机网络包含多台具有__自主____功能的计算机；把众多计算机有机连接起来要遵循规定的约定和规则.即__协议_____；计算机网络的最基本特征是__资源共享_______。

2、常见的计算机网络拓扑结构有：__星型________、__网状________、总线型、和___树型________。

3、常用的传输介质有两类：有线和无线。

有线介质有__双绞线______、____同轴电缆______、__光纤________。

4、网络按覆盖的范围可分为广域网、_局域网______、___城域网____。

5、TCP/IP协议参考模型共分了_4__层.其中3、4层是_应用层______、___传输层____。

6、电子邮件系统提供的是一种___存储转发_______服务.WWW服务模式为____B/S__________。

7、B类IP地址的范围是_______________________。

8、目前无线局域网采用的拓扑结构主要有________、________、___________。

9、计算机网络的基本分类方法主要有：根据网络所覆盖的范围、根据网络上主机的组网方式.另一种是根据____信息交换方式_____。

10、数据传输的同步技术有两种：_同步传输___________和异步传输。

11、用双绞线连接两台交换机.采用_交叉线______线。

586B的标准线序是_________________________________________。

12、多路复用技术是使多路信号共同使用一条线路进行传输.或者将多路信号组合在一条物理信道上传输.以充分利用信道的容量。

多路复用分为：_______频分_________、______波分__________、______时分__________和码分多路复用。

13、VLAN（虚拟局域网）是一种将局域网从_逻辑_____上划分网段.而不是从__物理____上划分网段.从而实现虚拟工作组的新兴数据交换技术。

⼤连交通⼤学《计算机⽹络》期末考试复习习题（精简版）计算机⽹络复习题⼀、单项选择1.Which of following is not an application-layer protocol? ( B)A. HTTPB. TCPC.SMTPD.FTP2.The PDU of network-layer is called ( C).A. messageB. segmentC. datagramD. frame3. An HTTP client often uses the (B ) method when the user fills out a form.A.GETB. POSTC. HEADD. PUT4.The default port number of DNS is(C )A.80B.21C.53D.255.Which of the following is not a mail access protocol? ( C)A.POP3B.IMAPC.HTTPD.SMTP6.Which protocol is not a network-layer protocol? (C )A.ICMP ProtocolB.routing protocolC.PPPD.IP Protocol7.The SYN segment is used for(B ).A. TCP flow controlB. TCP connection setupC. TCP congestion controlD. Closing a TCP connection8.Which field in a TCP segment is used for flow control? ( A)A. receive windowB. sequence numberC. acknowledgementD. Internet checksum9.A (A ) is the interface between the application layer and the transport layer within a host.A. socketB. bridgeC. EthernetD. hub10.In network-layer, which protocol is used for reporting errors? ( B)A.SMTPB.ICMPC.ARPD.CSMA11.Which protocol is an intra-autonomous system routing protocol? ( D)A. ARPB. ICMPC. BGPD. RIP12.MAC address is ( B) bits long.A.32B.48C.128D.6413. ( A ) means that the switch must receive the entire packet before it can begin to transmit the first bit of the packet onto the outbound link.A. store-and-forward transmissionB. FDMC. end-to-end connectionD. TDM14. In the following four descriptions, which one is correct? ( C )A In C/S architecture, clients communicate with each other directly.B In C/S architecture, client has a fixed well-known address.C In P2P architecture, peers communicate with each other directly.D In P2P architecture, peer has a fixed well-known address.15．Which of following is not an application-layer protocol? ( B )A. HTTPB. TCPC. DNSD. SMTP16. ( B ) header line indicates the time and date when the object was created or last modified.A. Date:B. Last-Modified:C. Connection:D.If-Modified-Since:17．A ( A ) provides logical communication between processes runningon different hosts. A ( ) provides logical communication between hosts.A. transport-layer protocol, network-layer protocolB. network-layer protocol, transport-layer protocolC. transport-layer protocol, application-layer protocolD. network-layer protocol, link-layer protocol18．Suppose TCP sender is in slow start state and the CongWin is8, then what’s the value of CongWin after one RTT? ( D )A. 9B. 10C. 4D. 1619．( B ) header allows the receiving user agent to take an appropriate action on the message.A. Content-Transfer-Encoding:B. Content-Type:C. From:D. To:20. The request message in the conditional GET must include the header line.C/doc/8fa2aaff48649b6648d7c1c708a1284ac8500507.html st-Modified/doc/8fa2aaff48649b6648d7c1c708a1284ac8500507.html st-ReferencedC.If-Modified-SinceD.If –Referenced-Since21. Which of the following services is not provided by TCP? （A）A.Delay guarantees and bandwidth guaranteesB.Reliable data transferC.Congestion controlD.Flow control22. In the LAN,（C ）protocol dynamically assign IP addresses to hosts.A.DNSB.ARPC.DHCPD.IP23. ___A_ is the ability to determine the interfaces to which a frame should be directed, and then directing the frame to those interfaces.A.ForwardingB.FilteringC.RoutingD.Switching24. Which of the following is not a routing protocol?（ A）A.TCPB.RIPC.OSPFD. BGP25. For 10BaseT, the maximum length of the connection between an adapterand the hub is A meters.A.100B.200C.500D.1026. In a TCP segment, ___A_ is the byte-stream number of the first bytein the segment.A.sequence numberB.aCK numberC.checksumD.port number27. A ( A ) provides logical communication between processes runningon different hosts. A ( ) provides logical communication between hosts.A. transport-layer protocol, network-layer protocolB. network-layer protocol, transport-layer protocolC. transport-layer protocol, application-layer protocolD. network-layer protocol, link-layer protocol⼆、填空1. A total nodal delay includes nodal processing delay, queuing delay,transmission delay , and propagation delay.2.In the context of a communication session between a pair of processes,the process that initiates the communication is labeled as the client . The process that waits to be contacted to begin the sessionis the server .3. A process sends messages into ,and receives messages from, thenetwork through its socket .4.FTP uses two parallel TCP connections to transfer a file, they aredata connection and control connection .5. DNS protocol translates hostname to IP address.6. A transport-layer protocol provides logical communication betweenprocesses running on different hosts. A network-layer protocolprovides logical communication between hosts .7.In IPv6 datagram format, IP address is 128 bits long.8.There are three 16-bit words: 0110011001100000, 0101010101010101,1000111100001100. Their checksum is 1011 0101 0011 1101 .9.RcvBuffer=100, LastByteRcvd=58, LastByteRead=23, then RcvWindow=6510. ARP protocol can convert the IP address to MAC address.11.R TT is the time it takes for a small packet to travel from clientto server and then back to the client.12.T he Internet mail system has three components which they are user。

计算机网络期末考试试卷及答案1、网络协议的三个要素为（语法）、（语义）和（同步）。

2、TCP/IP 体系的电子系统规定电子地址的格式为（收件人名所在主机的域名）。

3、数据链路层解决的三个基本问题是（封装成帧）、（透明传输）和（差错检测）。

4、用于在主机IP地址与MAC地址进行解析的协议称为（地址解析协议ARP ）协议。

5、自治系统部使用最多的路由协议是（ RIP）和（ OSPF 协议）。

BGP 协议外部6、已知IP地址是141.14.72.26，子网掩码是255.255.192.0，其网络地址为（ 141.14.64.0 ）。

7、传输层是为应用进程之间提供（端到端的逻辑通信），主要包括面向连接的（ TCP ）和无连接的（UDP ）两个协议。

8、负责将域名翻译成IP地址的系统叫做（）。

一、选择题（每题2分，共计30分）1、广域网覆盖的地理围从几十公里到几千公里。

它的通信子网主要使用（ B ）A、报文交换技术B、分组交换技术C、文件交换技术D、电路交换技术2、数据链路层中的数据块常被称为（ C ）A、信息B、分组C、帧D、比特流3、关于TCP/IP的IP层协议描述不正确的是（ D ）A、是点到点的协议B、不能保证IP报文的可靠传送C、是无连接的数据报传输机制D、每一个IP数据包都需要对方应答4、以下哪项不是IP路由器应具备的主要功能（C ）A、转发所收到的IP数据报B、为需要转发的IP数据报选择最佳路径C、分析IP数据报所携带的TCP容D、维护路由表信息5、用集线器连接的工作站集合（ A ）A、同属一个冲突域，也同属一个广播域B、不属一个冲突域，但同属一个广播域C、不属一个冲突域，也不属一个广播域D、同属一个冲突域，但不属一个广播域6、标准TCP不支持的功能是（ D ）。

A、可靠数据传输B、全双工通信C、流量控制和拥塞控制D、组播通信7、IP地址为224.0.0.11属于（ D）地址。

A、 A 类B、 B类C、C类D、D类8、高层互连是指传输层及其以上各层协议不同的网络之间的互连。

计算机网络期末考试题(含答案)第一题题目：请列举三种常见的网络拓扑结构，并简要说明每种拓扑结构的特点。

答案：1. 总线拓扑：该拓扑结构中，所有设备都连接到同一条总线上。

它的优点是简单、易于扩展，但是当总线发生故障时，整个网络将受到影响。

总线拓扑：该拓扑结构中，所有设备都连接到同一条总线上。

它的优点是简单、易于扩展，但是当总线发生故障时，整个网络将受到影响。

2. 星型拓扑：该拓扑结构中，所有设备都连接到一个中央设备（称为集线器或交换机）。

它的优点是易于安装和管理，但是如果中央设备发生故障，整个网络将无法正常工作。

星型拓扑：该拓扑结构中，所有设备都连接到一个中央设备（称为集线器或交换机）。

它的优点是易于安装和管理，但是如果中央设备发生故障，整个网络将无法正常工作。

3. 环型拓扑：该拓扑结构中，所有设备通过一个环形链路连接。

它的优点是每个设备都具有平等的通信权限，但是当环路中的一个设备发生故障，整个网络将被切断。

环型拓扑：该拓扑结构中，所有设备通过一个环形链路连接。

它的优点是每个设备都具有平等的通信权限，但是当环路中的一个设备发生故障，整个网络将被切断。

第二题题目：简要解释TCP/IP协议族中的三次握手过程。

答案：TCP/IP协议族中的三次握手过程用于建立可靠的数据传输连接。

1. 第一次握手：客户端向服务器发送一个SYN段（同步序列编号），用于请求建立连接。

客户端会将自己的初始序列号随机选择，并设置SYN标志位为1。

第一次握手：客户端向服务器发送一个SYN段（同步序列编号），用于请求建立连接。

客户端会将自己的初始序列号随机选择，并设置SYN标志位为1。

2. 第二次握手：服务器接收到客户端的SYN段后，确认请求建立连接，并发送一个带有SYN和ACK（确认）标志位的段作为响应。

服务器要在该段中将客户端的初始序列号+1，并设置自己的初始序列号。

第二次握手：服务器接收到客户端的SYN段后，确认请求建立连接，并发送一个带有SYN和ACK（确认）标志位的段作为响应。

Chapter 2 Application Layer1. In the following four descriptions, which one is correct?A In C/S architecture, clients communicate with each other directly.B In C/S architecture, client has a fixed well-known address.C In P2P architecture, peers communicate with each other directly.D In P2P architecture, peer has a fixed well-known address.2. In the context of a communication session between a pair of process, the process that initiates the communication is labeled as the , the process that waits to be contacted to begin the session is labeled as the .A client process, server processB sending process, receiving processC input process, output processD communicating process, connecting process3. A socket is the interface between within a host.A the network layer and the link layerB the link layer and the physical layerC the application layer and the transport layerD the transport layer and the network layer4. In the following applications, which one is a loss-tolerant application?A E-mailB file transferC instant messagingD real-time audio5. In the following applications, which one is a bandwidth-sensitive application?A E-mailB web applicationC real-time audioD file transfer6. The service of TCP can’t guarantee .A delivery of all data without errorB delivery of all data in the proper orderC the rate of deliveryD congestion control7. In the following applications, which one uses UDP?A E-mailB web applicationC file transferD DNS8. In the following descriptions about HTTP, which one is not correct?A HTTP uses non-persistent connections in its default mode.B HTTP uses TCP as its underlying transport protocol.C HTTP is a stateless protocol.D HTTP is client-server architecture.9. Suppose a web page consists of a base HTML file, 5 JEPG images and a java applet, and also suppose HTTP uses persistent connection without pipelining, the total response time is .A 2RTTB 8RTTC 12 RTTD 14RTT10. In HTTP response message, if the requested HTTP protocol version is not supported, the status code is .A 200B 301C 400D 50511. The port number of web application is .A 25B 20C 80D 5312. A network entity that satisfies HTTP requests on the behalf of an origin web server is .A server farmB server stackC proxy serverD edge server13. In the following descriptions about persistent connection, which one is not correct?A The server leaves the TCP connection open after sending a response.B Each TCP connection is closed after the server sending one object.C There are two versions of persistent connection: without pipelining and with pipelining.D The default mode of HTTP uses persistent connection with pipelining.14. FTP uses two parallel TCP connections to transfer a file, there are .A control connection and data connectionB receiving connection and sending connectionC client connection and sever connectionD program connection and process connection15. In the following descriptions about FTP, which one is correct?A FTP is p2p architecture.B FTP sends its control information out-of-band.C FTP uses persistent connection.D FTP is a stateless protocol.17. The Internet mail system has three components which they are .A user agent, SMTP, POP3B SMTP, POP3, IMAPC user agent, SMTP, IMAPD user agent, SMTP, mail server18. If the status code in HTTP response message is 404, it means .A Request succeeded.B The requested document doesn’t exit on this server.C This is a generic error code indicating that the request could not be understood by the server.D Requested object has been permanently mover.19. Comparison HTTP with SMTP, the correct is .A HTTP is a push protocol, and SMTP is a pull protocol.B In the default mode, both of them use persistent connection.C HTTP places all of the message’s objects into one message, and SMTP sends every object one by one.D HTTP requires each message to be in 7-bit ASCII format, and SMTP doesn’t impose this restriction.20. The headers in the MIME message must include except .A FromB Content-typeC Content-transfer-encodingD MIME version21. In the following protocol, which one is stateless?A POP3B SMTPC FTPD IMAP22. DNS means .A Data Name SystemB Data National SystemC Domain Name SystemD Domain National System23. There are three classes of DNS server except .A Root DNS serverB Local DNS serverC TLD server D Authoritative DNS server24. DNS provides some services except .A Host aliasingB Mail server aliasingC Load distributionD A single point of failure28. The time it takes for a small packet to travel from client to server and then back to the client is .A round-travel timeB next-hop timeC round-trip timeD prefix-matching time29. Suppose A ( with a Web-based e-mail account ) sends a message to B ( who accesses his mail server using POP3), which application-layer protocol is not used?A HTTPB SMTPC POP3D IMAP30. In the four following options, which protocol is included in Mail Access Protocol?A SMTPB DHCPC IMAPD FTP31. In FTP commands, is used to send user password to the server.A UserB PassC RetrD Stor32. The function of the additional header field in MIME Content-Type is .A to convert the message body to its origin non-ASCII formB to determine what actions it should take on message bodyC to send an E-mail to the receiving user agentD to indicate what type the message is33. In the four following options, which application is organized as hybrid of C/S and P2P architecture?A E-mailB OICQC File transferD Web application35.In the following options, from the application developer’s perspective, which is no t correct?A the network architecture is fixedB the network architecture provides a specific set of services to applicationsC the application architecture is designed by the physical devicesD the application architecture dictates how the application is organized over the various end systems36. There are three predominant architectures used in modern network applications, which one is not included?A the client-server architectureB the P2P architectureC a hybrid of the client-server and P2P architectureD a hybrid of the client-server and browser-server architecture37. In the following options about C/S architecture, which is not correct?A In C/S architecture, there is an always-on host, called the server.B In C/S architecture, there is an always-on host, called the client.C The server has a fixed, well-known address, called IP address.D Clients do not directly communicate with each other.39. A process sends messages into, and receives messages from, the network through its .A socketB programC clientD peer40. Which one is not defined by an application-layer protocol?A the types of messages exchangedB the syntax of various message typesC the semantics of the fieldsD rules for determining when and how to translate the socket41. HTTP can use two types of connections, which are .A persistent and non-persistent connectionB connection with pipelining and without pipeliningC TCP and UDPD parallel and serial connection42. takes for a small packet to travel from client to server and then back to the client.A RDTB thresholdC RTTD overhead43. The default mode of HTTP uses .A non-persistent connection with pipeliningB non-persistent connection without pipeliningC persistent connection with pipeliningD persistent connection without pipelining44. In HTTP request messages, the request line has three fields, there are .A the method field, the URL field and the HTTP version fieldB the method, the connection and URL fieldC the user-agent, the method and HTTP version fieldD the user-agent, the URL and the HTTP version field45. In the header lines of HTTP request message, if the field of Connection is close, it specifies .A the host on which object residesB what type of the user agentC that the browser wants the server to close the connection after sending the requested objectD which language can the browser receive46. In HTTP response message, if the status code is 404, it means .A request succeeded and the information is returned in the responseB requested object has been permanently movedC the requested HTTP protocol version is not supported by the serverD the requested document does not exist on this server47. is a network entity that satisfies HTTP requests on the behalf of an origin Web server.A proxy serverB local serverC DNS serverD Web server48. In the following four options about web cache, which one is not correct?A A web cache is both a server and a client at the same time.B A web cache is purchased and installed by an ISP.C A web cache can raise the response time for a client request.D A web cache can reduce traffic on an ins titution’s access link to the Internet.49. The request message in the conditional GET must include the header line.A Last-ModifiedB Last-ReferencedC If-Modified-SinceD If –Referenced-Since50. FTP uses two parallel connections to transfer a file, they are .A TCP and UDP connectionB connection with pipelining and without pipeliningC control an data connectionD client-server and browser-server connection51. In FTP commands, which one is used to ask the server to send back a list of all files in the current remote directory?A USERB PASSC LISTD RETR52. In the Internet mail system, allow users to read, reply to, forward, save and compose message.A User agentsB mail serversC SMTPD TCP53. The two key MIME headers for supporting multimedia are .A Content-Type and MIME-VersionB Content-Type and Content-Transfer-EncodingC Content-Transfer-Encoding and MIME-VersionD MIME-Version and MIME-Type54. For Internet mail, the mail access protocol is used to .A transfer mail from the recipient’s mail server to the recipient’s user agentB transfer mail from the sender’s mail server to the recipient’s mail serverC translate the mail from the sender’s mail serverD translate the mail into the recipient’s mail server55. POP3 progresses through three phases, which they are .A authorization, translation and transactionB authorization, translation and updateC authorization, transaction and updateD translation, transaction and update56. In the following four services, which one can not provide by DNS?A Host aliasingB Mail server aliasingC translate hostname to IP addressesD translate MAC addresses to IP addresses57. There are three classes of DNS servers, there are .A root DNS server, top-level domain DNS server and local DNS serverB root DNS server, top-level domain DNS server and authoritative DNS serverC root DNS server, local DNS server and authoritative DNS serverD root DNS server, local DNS server and top-level domain DNS server58. In the following four options about POP3, which one is not correct?A The user agent employed only three commands: List, Retr and QuitB The server does not carry state information across POP3 sessionsC The port number is 110D The POP3 protocol does not provide any means for a user to create remote folders and assign messages to folders.64. In the following four options about P2P file-sharing, which one is not correct?A P2P file-sharing is highly scalable.B P2P file-sharing relies on P2P architecture.C The means for locating content in different P2P file-sharing are different.D P2P file-sharing systems not only share MP3s,but also videos, software, documents and images.66. If the header line Connection is close, it means that the client wants .A persistent connection with pipeliningB persistent connection without pipeliningC nonpersistent connectionD not connection67. In HTTP request message, the entity body is empty with the method, but is used with the method.A GET, POSTB POST,GETC GET, HEAD D POST, HEAD68. In HTTP response message, if the Date: header ;one indicates the time Fri. 08 Aug. 2008 12:00:00 GMT, the Last-Modified: header line can not be .A Fri. 08 Aug. 2008 11:00:00 GMTB Fri. 08 Aug. 2008 11:30:00 GMTC Fri. 08 Aug. 2008 12:00:00 GMTD Fri. 08 Aug. 2008 12:30:00 GMT69. In the following four options, which one is not the part of cookie technology?A Cookie header lines in the HTTP response message and request message.B One cookie header file kept on the user’s end system and managed by the user’s browser.C A network entity that satisfies HTTP requests on the behalf of an origin Web server.D A back-end database at the Web site70. On-top of stateless HTTP, can be used to create a user session layer.A proxy serverB Web cacheC cookieD socket71. Processes communicate with each other by reading from and writing to .A programsB threadsC socketsD channels72. In the following four options about network architecture, which one is not correct?A The network architecture is fixed.B The network architecture provides a specific set of services to application.C The network architecture is designed by application developer.D The network architecture dictates how the application is organized over special server.73. In Client-Server architecture, the clients visit the server’s through .A client’s socketB client’s IP addressC server’s socketD server’s IP address74. can be thought of as a program that is running within end system.A processB threadC socketD context75. API means .A Application Program InterfaceB Application Process InterfaceC Appellation Program InterfaceD Appellation Process Interface76. One host can be running many network applications, so the system assigns them differentto distinguish each other.A IP addressB port numberC hostnameD section77. In the following four applications, which one is both bandwith-sensitive and require tight timing constraints?A real-time audioB file transferC E-mailD Web documents78. The port number of the Web server is .A 25B 20C 80D 808079. The port number of the mail server is .A 25B 20C 80D 808080. Look the URL /rjxy/index.html, the object’s path name is .A B /rjxyC /rjxy/index.htmlD index.html81. Each URL has components, they are .A transport protocol and object’s path nameB host name and object’s path nameC transport protocol and host nameD client name and server name1. Consider an HTTP client will request a WEB page from a WEB server. Suppose the URL of the page is /somedepartment /somedir/exp.html. The client does not want to use persistent connections and want to receive French version of the object. The user agent is Windows NT 5.1. Give the request message according to the given format.Request line:Header lines:2. Telnet into a Web server and send a multiline request message. Include in the request message the If-modified-since: header line to force a response message with the 304 Not Modified status code.Solution:Request line:Header lines:3. Suppose within you Web browser you click on a link to obtain a Web page. The IP address for the associated URL is not cached in your local host, so a DNS look-up is necessary to obtain the IP address. Suppose that n DNS servers are visited before your host receives the IP address from DNS; the successive visits incur an RTT of RTT1,…，RTT n. Further suppose that the Web page associated with the link contains exactly one object, consisting of a small HTML text. Let RTT0 denote the RTT between the local host and the server containing the object. Assuming zero transmission time of the object, how much time elapses from when the client clicks on the link until the client receives the object?5. Suppose that you send an e-mail message whose only data is a microsoft excell attachment. What might the header lines (including MIME lines) look like?。