计算机网络--ICMP

该文档是关于计算机网络中实验ICMP部分的答案。题目为英文，如下，答案为中文，部分有图文解释。 Ethereal Lab: ICMP Version: July 2005 © 2005 J.F. Kurose, K.W. Ross. All Rights Reserved Computer Networking: A Topdown Approach Featuring the Internet, 3rd edition. In this lab, we’ll explore several aspects of the ICMP protocol: • ICMP messages generating by the Ping program; • ICMP messages generated by the Traceroute program; • the format and contents of an ICMP message. Before attacking this lab, you’re encouraged to review the ICMP material in the textbook (Section 4.4.3 in the 3rd edition.) We present this lab in the context of the Microsoft Windows operating system. However, it is straightforward to translate the lab to a Unix or Linux environment. 1. ICMP and Ping Let’s begin our ICMP adventure by capturing the packets generated by the Ping program. You may recall that the Ping program is simple tool that allows anyone (for example, a network administrator) to verify if a host is live or not. The Ping program in the source host sends a packet to the target IP address; if the target is live, the Ping program in the target host responds by sending a packet back to the source host. As you might have guessed (given that this lab is about ICMP), both of these Ping packets are ICMP packets.