云南大学软件学院计算机网络原理期中试卷王世普.doc

云南大学2015至2016学年上学期软件学院2014级 《计算机网络原理》期中考试试卷（闭卷）答案 满分：100分 考试时间：100分钟 任课教师：王世普 第一题答题卡： 小题号 1 2 3 4 5 6 7 8 9 10 回 答 B D D B A B C A A C 第二题答题卡： 小题号 1 2 3 4 5 回 答 × √ √ × × 一、选择题（项1分，共0分请将选择结果填入第一题答题卡）1）. （1）2．A GIF image is sent as email ,What is the content-type （2） . （2）A．multipart/mixed B．multipart/image C．image/JPEG D．image/gif 3．A user want to send some forms（表单） Web server using HTTP protocol, the request line method is （3） . （3）A．GET B．PATCH C．MOVE D．POST 4．If a TCP segment carries data along with an acknowledgment, this technology is called （4）4）’s help 5．TCP is a （） ransport layer protocol that ensure data to be exchanged reliably by（） requires set up connection before data exchanged by ( 7 )-way handshaking. （）A．connectionB．connectionlessC．joinD．disconnection （）A．datagramsB．acknowledgementsC．dataD．segment （）A．one B．two C．three D．four 6A user requests a Web page that consists of a basic HTML file and 5 JPEG image files. dtrans denoting the time to transfer a file. The total time is (8) to request the Web page in Nonpersistent connections mode? （8）6(2RTT+ dtrans) B. 2RTT+6 dtrans C. RTT+6 dtrans D.6(RTT+ dtrans) 7． Host A sends a TCP segment (Seq = 1, ACK = 111) to host B and Host B replies with a TCP segment (Seq = 111, ACK = 81). The payload length of the TCP segment from host A to host B is ( 9 ) . （9）A80 bytes. B．81 bytes. C．82 bytes. D．unknown 8．As a data packet moves from the lower to the upper layers, header are （10）10）、（问题1分，共5分的打“√”错误的“×”，请判断填入二题答题卡）1. The DNS defines a distributed, hierarchical database that provides only hostname to IP address mappings. ( × ) 2. In SR protocol, sender only resends pkts for which ACK not received. ( √ ) 3．the send window maximum size of GBN protocol is equal to 2k-1. ( √ ) 4．The UDP header checksum is recomputed at every routers. ( × ) 5．Suppose that the last SampleRTT in a TCP connection is equal to 1 sec. Then Timeout for the conn