深圳大学期末考试数据通信与计算机网(共4页).doc
精选优质文档-倾情为你奉上深圳大学期末考试数据通信与计算机网 Shenzhen University final exam data communication and computer networks 一、单项选择题(每小题 1 分,共 20 分) A multiple-choice (Paper 1 minute, 20 points) 1. 1. 故障出现的频率和网络故障恢复时间是网络 _ 的度量。 The frequency and network failure recovery time is a measure of network _. a. 性能 a. Performance b. 安全性 b. Security c. 可靠性 c. Reliability d. 可行性 d. feasibility 2. 2. 线缆断开会使 _ 拓扑结构的所有传输中断。 Disconnect all cables will interrupt transmission _ topology. a. 网状 a. net b. 星型 b. Star c. 总线 c. Bus d. 环状 d. ring 3. 3. 当分组从低层传到高层时,头部被 _ 。 When the packet is transmitted from the lower level, the head is _. a. a. 去除 Removed b. b. 添加 Add to c. c. 重排 Rearrange d. d. 修改 Modify 4. 4. 第二层位于物理层和 _ 层之间。 The second layer is located between the physical layer and _ layers. a. 网络 a. Network b. 数据链路 b. Data link c. 传输 c. Transmission d. 以上都不正确 d. None of the above 5. 5. _ 多路复用技术用于传输数字信号。 _ Multiplexing techniques for transmission of digital signals. a.FDM a.FDM b.TDM b.TDM c.WDM c.WDM d. 以上都不正确 d. None of the above 6. 6. TSI 中,由 _ 控制存储在 RAM 中的时隙值的传递顺序。 TSI, a delivery order from the _ slot value stored in the RAM of the control. a. 纵横制交换机 a. crossbar switches b. 收发器 b. Transceiver c. 控制单元 c. The control unit d. 交叉点 d. intersection 7. 7. _ 校检方法使用反码算法。 _ School inspection method using anti-code algorithms. a. a. 简单奇偶校检 Simple parity check b. b. 校检和 Checksum c. c. CRC CRC d. d. 两维奇偶校检 Popovich even two school inspection 8. 8. 对于停等 A RQ 来讲,要发送 n 个数据分组,需要 _ 个确认。 For stopping, etc. A RQ concerned, to send data packets n, need _ confirmation. a. a. n-1 n-1 b. b. n n c. c. n+1 n + 1 d. d. 2n 2n 9. 9. 当数据和确认在同一帧发送时,称作 _ 。 When data is transmitted in the same frame and confirmation, called _. a. a. 背负式 Backpack b. b. 捎带 Incidentally c. c. 捎带打包 Incidentally pack d. d. 好的主意 Good idea 10. 10. 在 _ 中,站点不检测介质。 In _, the site does not detect the media. a. a. ALOHA ALOHA b. b. CSMA/CD CSMA / CD c. c. CSMA/CA CSMA / CA d. d. 令牌传递 Token Passing 11. 11. _ 应用于无线局域网中。 _ Used in wireless LAN. a. a. CSMA CSMA b. b. CSMA/CD CSMA / CD c. c. CSMA/CD CSMA / CD d. d. 令牌传递 Token Passing 12. 12. _ 不是以太网的信源地址。 _ Source address is not Ethernet. a.3A-7B-6C-DE-10-00 a.3A-7B-6C-DE-10-00 b.EE-AA-C1-23-45-32 b.EE-AA-C1-23-45-32 c.46-14-32-25-FE-F4 c.46-14-32-25-FE-F4 d.3B-21-32-DC-34-56 d.3B-21-32-DC-34-56 13. 13. 一个 40 个站点的传统以太网被分割成四个冲突域,这就意味着在任何一个时间最多有 _ 个站点竞争访问介质。 Traditional Ethernet is divided into four collision domains a 40 site, which means that at any one time up to _ competition sites accessible medium. a.160 a.160 b.40 b.40 c.10 c.10 d.1 d.1 14. 14. 有冗余网桥的系统可能在系统中存在 _ 问题。 Redundant bridge system may exist _ problem in the system. a. a. 过滤 Filtration b. b. 循环 Cycle c. c. 生成树 Spanning Tree d. d. 以上所有项 All of the above items 15. Fifteen. _ 可以用来讲站点分组成 VLAN 。 _ Can use in terms of sites grouped VLAN. a. a. MAC 地址 MAC address b. b. IP 地址 IP addresses c. c. 端口号 The port number d. 以上所有项 d. All of the above items 16. 16. 假定 IP 地址为 18.250.31.14 ,且子网掩码是 255.240.0.0 ,则该子网的地址是 Whose IP address is 18.250.31.14, and subnet mask 255.240.0.0, the address is the subnet _ 。 _. a.18.31.0.14 a.18.31.0.14 b.18.0.0.14 b.18.0.0.14 c.18.250.0.0 c.18.250.0.0 d.18.240.0.0 d.18.240.0.0 17. 17. 226.1.2.3 这个 IP 地址所属的类别是 _ 。 Type 226.1.2.3 The IP address belongs is _. a. a. A 类 A Class b. b. B 类 Class B c. c. C 类 Class C d. d. D 类 Class D 18. 18. IP 头部的尺寸是 _ 长。 IP header size is _ long. a.20 字节 a.20 byte b.60 字节 b.60 byte c.2060 字节 c.20 60 bytes d. 依 MTU 而定 d. according to MTU may be 19. 19. _ _ 是一种内部路由协议。 It is an internal routing protocol. a. a. RIP RIP b. b. OSPF OSPF c. c. BGP BGP d. d. (a) 和 (b) (A) and (b) 20. 20. 在距离矢量路由选择中, _ 一台路由器就将信息发送出去。 In distance vector routing, a router will be _ message sent. a. a. 按固定的时间间隔 At regular intervals b. 仅当其表中发生了变化时 b. Only when it is time to change the table c. c. 仅当加入了一台新的主机时 Only when we are adding a new host d. d. 仅当加入一个新的网络时 Only when adding a new network 三、简答与计算题 ( Third, short-answer and Calculation ( 每小题 20 分,共 60 分 ) Mei Xiaoti 20 points, a total of 60 points) 1. 关于网络分层模型和物理层,试回答下列问题: 1. With regard to the hierarchical model and the network physical layer, try to answer the following questions: 1 )数据通信系统有哪几个组成部分? 1) data communication system has several components which? ( 5 分) (5 points) 2 )请描述因特网 5 层模型的分层结构以及简要描述每一层的功能。 2) Please describe the hierarchical structure of the Internet 5-layer model and a brief description of the function of each layer. ( 5 分) (5 points) 3 ) 20 个数字信号源使用同步 TDM 实现多路复用,每个信号源的速率是 100kbps ,每 3) 20 digital source to achieve synchronous TDM multiplexing, rate each source is 100kbps, every 个输出时隙携带来自每个数字信号源的两位,但帧需要增加一位用于同步,试回答 Output slot carries two from each of the digital signal source, but need to add a frame for synchronization, test answer 下列问题: The following issues: a. a. 以位为单位的输出帧的长度是多少? Length in bits of the output frame is the number? b. b. 输出帧速率是多少? Output frame rate? c. c. 输出帧持续时间多长? Output frame duration long? d. d. 输出数据的速率是多少? The output data rate is the number? e. e. 系统效率是多少? System efficiency is the number? ( 5 分) (5 points) 4 )电路交换中使用哪两种交换机? 4) What are the two switches in the circuit-switched to use? (2 分 ) (2 points) 5 )在一台三级纵横制交换机中,试确定交叉点数量 n ,已知输入 / 输出线路数为 20 ,第一级和第三级交换机的数量为 4 ,第二级交换机的数量为 2 。 5) In a three-tier crossbar switch, determine the number of intersection n, a known input / output line number is 20, the number of first and third stages of the switch to 4, the number of the second stage of the switch is 2 . ( 3 分) (3 points) 2. 关于数据链路层,试问: 2. With regard to the data link layer, ask: 1 )系统接收到下列块,假定使用两维的偶校验,请问哪些位为差错位? 1) The system receives the following block, assumed two-dimensional parity, may I ask what position is erroneous bits? ( 4 分) (4 points) 2 )试说出 IEEE 2) try to tell IEEE 802.3 传统以太网的四种物理层实现。 Four traditional Ethernet 802.3 physical layer implementation. ( 4 分) (4 points) 3 )在 CSMA/CD 协议中,站点什么时候访问介质? 3) In the CSMA / CD protocol, a site when accessing the media? 如果介质处于忙状态应该怎么办? If the media is busy, how should we do? 站点如何确定传输是成功还是失败? Site how to determine the success or failure of the transmission? 如果存在冲突,站点将如何处理? If a conflict exists, the site will be handled? ( 7 分) (7 points) 4 )对下列数据进行位填充: 4) the following data bit stuffing: ( 5 分) (5 points) 3. 关于网络层,试回答下列问题: 3. With regard to the network layer, try to answer the following questions: 1 )试列出网络层的 5 种协议的名称。 1) lists the name of the network layer test five kinds of agreements. ( 5 分) (5 points) 2 )试说出分类寻址中 IP 地址的分类以及各类地址的起始范围。 2) try to tell the starting area classification addressing classification and a variety of address IP address. ( 3 分) (3 points) 3 )下图是 IPv4 的数据包头部格式: 3) The following is an IPv4 packet header format: a. a. TTL 的用途是什么? What is the use of TTL? ( 2 分) (2 points) b. b. 解释该头部结构中的字段如何支持数据报分段。 Explain the header fields in a structure how to support packet fragmentation. 为什么需要分段? Why segments? ( 3 分) (3 points) 4 )利用距离向量路由,一个路由器有下面的路由表: 4) the use of distance-vector routing, a router's routing table below: 距离 Distance 线路 Line Net1 Net1 7 7 A A Net3 Net3 2 2 C C Net6 Net6 8 8 F F Net7 Net7 4 4 E E Net9 Net9 4 F 4 F 该路由器从路由器 F 接收到下面的 RIP 报文: The router receives from the router F to below RIP messages: Net1 Net1 4 4 Net3 Net3 6 6 Net4 Net4 5 5 Net6 Net6 4 4 Net9 Net9 7 7 请说明该路由器的更新路由表。 Please explain to update the routing table of the router. ( 7 分) (7 points) 专心-专注-专业