Ethereal offers more protocol decoding and reassembly than any free sniffer out there and ranks well among the commercial tools. You've all used tools like tcpdump or windump to examine individual packets, but Ethereal makes it easier to make sense of a stream of ongoing network communications. Ethereal not only makes network troubleshooting work far easier, but also aids greatly in network forensics, the art of finding and examining...
an attack, by giving a better "big picture" view. Ethereal Packet Sniffing will show you how to make the most out of your use of Ethereal.
In the first chapter of Ethereal packet sniffing, the authors discuss what network analysis is, who uses it and how it works. They explain how to detect and protect against sniffers, and provide information about network analysis and policy.
Excerpted from Ethereal Packet Sniffing by Angela Orebaugh and Gilbert Ramirez (ISBN: 1-932266-82-8). Copyright 2004, Syngress Publishing, Inc. All rights reserved.