I've actually had to read this book for module on my university course (had the exam last week, think it went pretty well), and it's a shame that many people will likely avoid it for fear of it requiring in-depth technial knowledge of the internet, other networks and computers in general. Whilst a little knowledge of such things is needed, is only along the lines of what they are and what they are used for.

The book has been written as a start-to-finish book, i.e. it's not meant for reading the different chapters at leisure - there is definite follow-on. It never reaches too steep a learning curve, but more impressive is the fact that it manages to cover as wide a range of sub-topics that "digital security" covers, as it does, whilst never feeling like it's skimped on any of those sub-topics. It helps that it's not meant to look at any particular sub-topic too closely - you find full details on how to build a firewall, for instance, or how to design a cryptographic algorithm. But it also provides a little background on topics of especial interest, such as the US and UK governments' usage of digital security (in particular cryptography and their citizens' right to privacy versus the need for evidence gathering).

Most interesting of all, are the main important points that network administrators and users should really take note of (this includes people who use the internet). Most of them, I must admit, I kind of knew already (however reading them from one of the foremost security experts around helps keep them in my mind), but I still don't follow all of them as I should. I do follow them better than the average internet user, though, otherwise e-mail worms and trojans and those stupid hoax e-mails would not continue being so successful.

In short, if you use the internet regularly, or some kind of computer network at work, this really is a must read.