Network Intrusion Detection Signatures, Part 1
This is the first in a series of articles on understanding and developing signatures for network intrusion detection systems. In this article we will discuss the basics of network IDS signatures and then take a closer look at signatures that focus on IP, TCP, UDP and ICMP header values. Such signatures ignore packet payloads and instead look for certain header field values or combinations of values. By learning about network IDS signatures, you’ll have more knowledge of how intrusion detection systems operate, and you’ll have a better foundation to write your own IDS signatures.
