I wanted to like this book, seeing as how I've made intrusion detection an important part of my career (the book spends a few pages discussing a paper I wrote), and there are no good offline resources on the subject. Unfortunately, I found little to appreciate in this book, which could have benefited greatly from better technical editing, a sharper concept of what its audience is, and (unfortunately) a better grounding in the subject matter.
The most important problem with this book will be obvious to most readers. Escamilla doesn't address the subject of intrusion detection until midway through the book, opting instead to fill the first half of the book with background information about computer security. This information is presented poorly (and with glaring inaccuracies). Almost all of it is covered better in other books, which readers unfamiliar with network security will need to buy anyways to make the intrusion detection concepts discussed in the latter half of the book accessible.
Unfortunately, the relevant half of the book isn't much better. A confused mish-mash of technologies are presented under the banner of I-D (I know of very few people in the security industry who consider security scanners to be I-D systems), and the most widely used forms of I-D are given scant coverage.
Worse still, the author profiles real commercial I-D systems (towards the end of the book). Apart from the fact that this information was unsalvageably outdated before the book made it to the press, it's also biased. Descriptions of one system span 3 pages, while another merits a single paragraph. Many important systems (which were widely known at the time of this book's release) are not covered at all. And, predictably, most of the details about the commercial systems covered read like marketing material, with almost no comparisons to the other systems covered.
Although this book is a mess, it's not an unrecoverable one. The authors descriptions of Do-It-Yourself intrusion detection on Unix systems is competant, if not revolutionary, and is almost reminiscent of Cheswick and Bellovin's work in _Firewalls_and_Internet_Security_. A better informed, more coherent second revision of this book would be worth looking at.
Unfortunately, there's very little to recommend this book. A critical and informed reader might get some value out of it, but nothing that couldn't be obtained more easily from the Internet. At its worst, however, this book can be misleading, and is thus an inappropriate introduction to its subject. Overall, a deeply flawed book. Steer clear.
