"This is a well-written textbook, one destined to become an undergraduate favorite in the fascinating and rewarding study of cryptology." — Atul Prakash, University of Michigan "Dr. Spillman's Cryptographic Analysis Program, (CAP), is not only a fantastic teaching tool, it's very useful to the cryptanalyst as well. I've used it in teaching a practical security course for the last four years." — Scott Orr, Indiana University-Purdue University, Indianapolis Some people work hard at encoding their secrets; other people work just as hard at deciphering them. Students of cryptology must learn to understand the thinking and techniques of both sides. As Dr. Spillman explores the world of cryptology, he spans introductory to advanced topics, presenting the history and methodology of spies, code breakers, code talkers, and present-day computer hackers and attackers. The cryptographic analysis software included with the book enables students to perform simple hands-on activities that teach them to think like a cryptographer as they learn to fend off attacks or secure software systems. Important features: Coverage of both classical and contemporary cryptology allows students to learn current methods by understanding their origins in early work. The included CAP software package allows students to test their skills while instructors can add interesting new challenges. Stream cipher coverage lets students see how an important cipher is implemented in practice. Use of block ciphers in a network introduces students to the actual use of a cipher system. Charts ending each chapter illustrate how newly covered ciphers fit in and the interrelationships that exist between ciphers. Optional chapter on quantum computing offers advanced study topics.