Excerpts from the book description:

Few frontline system administrators can afford to spend all day worrying about security. But in this age of widespread virus infections, worms, and digital attacks, no one can afford to neglect network defenses.

Written with the harried IT manager in mind, Open Source Security Tools is a practical, hands-on introduction to open source security tools. Author Tony Howlett has reviewed assortment of these free and low-cost solutions to provide reader with the "best of breed" for all major areas of information security.

Inside, reader will find everything from how to harden Linux and Windows systems to how to investigate breaches with Sleuth Kit, Autopsy Forensic Browser, and Forensic Tool Kit. For each security task described, the author reviews the best open source tools and how to use them and also provides a case study and sample implementation. Covered tasks include:

* Installing an open source firewall using Ipchains, Iptables, Turtle firewall, or Smoothwall
* Scanning ports and testing for vulnerabilities using Nmap, Nlog, Nmap for Windows, Nessus,and NessusWX
* Using sniffers and network-intrusion systems, including Tcpdump, Ethereal, Windump, Snort™, and Snort™ for Windows
* Tracking and analyzing collected data with Swatch, ACID, and NCC
* Encrypting communications with PGP, GnuPG, SSH, and Free S/WAN

This reference also tackles wireless security and covers tools such as Kismet Wireless, Airsnort, and Netstumbler.