Cryptography Demystified is a great intro guide to cryptography, well worth its price.

The simplicity, yet thoroughness, which he uses to explain one of the more difficult topics in engineering and mathematics shows that Dr. Hershey is a true expert in the field. I highly recomend this book for both the novice and the advanced reader.

If you are looking to expand your mind, think about learning Cryptography. It is an excellent discipline to help you think in new ways. If you decide you want to learn Cryptography, this is the book for you. The book is written in modules, making it easy to digest. The book is equally suitable for a formal classroom or self-study environment. Using the book for self study is enhanced by the modular format, superb clarity of the teaching, the well-explained answers to the problems, and the appropriately injected humor. People that need to learn Cryptography will undoubtedly have this book on their shelf, whether they are an expert or beginner. I would like to speak to the people that don't need to learn Cryptography - this book is for you too, as you will enjoy learning the thought processes of Cryptography that will enhance your creativity in any field. This book is a gift.

A rewarding introduction to this unique and interesting discipline. Using working examples, related mathematics, and subject history, Dr. Hershey illustrates important aspects of effective crypto system design. Part of the how-to is to understand how-not-to and the text uncovers some subtle flaws in crypto design and associated consequences. Connections to other areas in communications engineering and applied number theory make the book valuable for a broad audience.

The presentation is insightful, mature, innovative, and enjoyable. Certainly recommended.

As an electrical engineer new to the subjects of cryptography and number theory, I found this book provided a solid introduction to the fundamentals of cryptography. John Hershey conveys the important subtleties and pitfalls essential to evaluating cryptographic systems. He lays out the basic paradigm and takes you step by step through the algorithms and mathematics in a straight forward easy to follow manner. By the end you will have acquired the tools necessary to understand more advanced cryptographic schemes. Overall, I would highly recommend this book to others interested in gaining knowledge about the inner workings behind today's cryptographic systems.