The Code Book

I have to say that I was somewhat disappointed with this book. Not with the prose, as I read it from cover to cover over a day or so, but with the content. I have a passing interest in cryptography and over the course of a few years became acquainted with of most of what is included in this book. As Simon Singh acknowledges, the definitive story of cryptography (up to 1955) is David Kahn's book The Code Breakers.

As the author says 'History is punctuated with codes. They have decided the outcomes of battles and led to the deaths of kings and queens. I have therefore been able to call upon stories of political intrigue and tales of life and death to illustrate the key turning points in the evolutionary development of codes.' Interesting as this approach is, he readily admits that this account is not definitive and refers the reader to the appended list of further reading for more detail.

This book charts the evolution of codes from Egyptian times to the known present day. I deliberately say the known present day as code making and code breaking is an on-going challenge where secrecy is all important. Who really knows today if the RSA (Rivest, Shamir, Adleman) public-key system is still secure. Apparently a similar public-key cryptography was independently invented at the British Government's Communication Headquarters (GCHQ), a fact only made public in 1997.

A good part of this book is about public-key cryptography and the why and how it is used. With the exploding use e-mail and the Internet and the ease with which messages can be intercepted and altered this is timely.

Those wanting a readable introduction to cryptography will find this book interesting. Those who are 'in the trade' will find that it contains no new material. Those wanting more detail on their favourite code or code breaker would best look for a specific book on that topic.

There is a sweetener though. Read the book, absorb the techniques and then try your hand at solving the 10 cryptographic challenges at the end. First to do so could win £10,000 (A$25,000). I've got through to number 3. But somehow I think Simon Singh's money is safe for the time being.