In Mastering Network Security, Chris Brenton presents a complete portrait of all the things that can go wrong with a computer network and provides a thorough discussion of the tools available to counteract them. This book proceeds to explain how malicious software, external attackers, angry insiders, software bugs, and other evil entities can bring down a system. Most of the focus here, however, is on system attacks from the outside. Brenton devotes much attention to the tools you can use to thwart attackers.
This book walks the reader through a security audit and the process of developing an effective security policy. While some of the author's advice in this area may seem like common sense, it's helpful to have the many related issues summarized. Then, on the theory that it's easier to secure territory you know well, Brenton provides an overview of internetworking technologies--notably, Virtual Private Networks (VPNs)--and their inherent security characteristics.
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