Intrusion Detection by Rebecca Bace is an intriguing book that focuses on intrusion detection, yet covers a lot more than pure intrusion detection-related issues. In a nutshell, this book covers what intrusion detection is, its history, why it is important, types of intrusion detection systems (IDSs) that have been developed over the years, ways to do it, how to make it work in the real world, and legal issues associated with it.