This is the first quick reference guide to the do's and don'ts of creating high quality security systems. Ross Anderson, widely recognized as one of the world's foremost authorities on security engineering, presents a comprehensive design tutorial that covers a wide range of applications. Designed for today's programmers who need to build systems that withstand malice as well as error (but have no time to go do a PhD in security), this book illustrates basic concepts through many real-world system design successes and failures. Topics range from firewalls, through phone phreaking and copyright protection, to frauds against e-businesses. Anderson's book shows how to use a wide range of tools, from cryptology through smartcards to applied psychology. As everything from burglar alarms through heart monitors to bus ticket dispensers starts talking IP, the techniques taught in this book will become vital to everyone who wants to build systems that are secure, dependable and manageable.