I found Rolf Oppliger's INTERNET AND INTRANET SECURITY (SECOND EDITION) to be an invaluable tool for helping me get up to speed on some of the fundamental aspects involved in computer network security. This taught me a lot that I needed to know and it did so without being confusing. This book was an assigned text for an Enterprise Security class that I took, and it was an invaluable learning aid, as well as a great resource.

The text covers fundamentals (a TCP/IP networking overview, OSI Architecture, various cryptographic techniques and the attacks they are designed to thwart), access control (explaining packet-filters, application and circuit level gateways, and firewalls), and communications protocols/security (Network Access Layer, Internet Layer, Transport Layer, Application Layer, and message security protocols). Also included is a chapter on Public Key Infrastructures. The book is almost totally focused on teaching theory, with only scant attention paid to real-world implementations. This is not a drawback. If a student learns everything this book has to offer, then that will be a huge advantage when it comes time to turn one's attention towards actual applications.

Most topics that Oppliger discusses include a brief history of the subject. This allows the student to really get a handle on why a system evolved in the way that it did. Also helpful are the numerous pointers to web pages and other texts to supplement the information given here. This book is mostly text-based; pictures, figures and tables are present but used sparingly.

Overall, I would recommend this book to any student new to the field or any novice looking for insight into the topics of computer network security. It casts a very wide net, and while most specifics will be given more depth in other, more specialized books, the amount of information revealed here is more than adequate.