Securing Your Business with Cisco ASA and PIX Firewalls

Network Intrusion Prevention

Network-based intrusion prevention is a key component of defense in depth and the ASA/PIX Security Appliance. The purpose of this technology is to recognize and stop attacks when they flow through the appliance. The ASA/PIX version 7 operating system implements two basic forms of network intrusion prevention; one is signature-based, and the other is behavior-based and is called application firewall features.

Signature-based intrusion prevention is similar to the way that antivirus software works on a host. The prevention device looks for a sequence of bytes on the network that matches an attack string; if the string matches, the device can either drop the traffic or report the attack to a logging server. Using the ...