计算机网络实验3TCP实验.doc

计算机网络实验报告三 TCP实验 1. What is the IP address and TCP port number used by the client computer (source) that is transferring the file to ? To answer this question, it’s probably easiest to select an HTTP message and explore the details of the TCP packet used to carry this HTTP message, using the “details of the selected packet header window” (refer to Figure 2 in the “Getting Started with Wireshark” Lab if you’re uncertain about the Wireshark windows). 答：client computer (source)：IP address：02 TCP port number：1161 2. What is the IP address of ? On what port number is it sending and receiving TCP segments for this connection? 答：the IP address of ：IP address：2 port number：80 3. If you have been able to create your own trace, answer the following question:What is the IP address and TCP port number used by your client computer(source) to transfer the file to ? 答：My client computer: IP address:0 4. What is the sequence number of the TCP SYN segment that is used to initiate theTCP connection between the client computer and ? What is it in the segment that identifies the segment as a SYN segment? 答：sequence number:0 ；syn 被设置为1说明是syn段。 5. What is the sequence number of the SYNACK segment sent by to the client computer in reply to the SYN? What is the value of the ACKnowledgement field in the SYNACK segment? How did determine that value? What is it in the segment that identifies the segment as a SYNACK segment? 答：The sequence number of the SYNACK segment sent by is:0； SYNACK segment 中 ACKnowledgement 的值为1； ACKnowledgement number的值为SYN消息中sequence number加上1所得； SYN 和Acknowledgement f都置为1说明这是一个SYNACK segment. 6. What is the sequence number of the TCP segment containing the HTTP POST command? Note that in order to find the POST command, you’ll need to dig into the packet content field at the bottom of the Wireshark window, looking for a segment with a “POST” within its DATA field. 答：第四号报文段是包含 HTTP POST 命令的TCP segment.且报文段的序列号为1. 7. Consider the TCP segment containing the HTTP