Sarah is the Irish schoolgirl who shot to fame in 1999 when she created a new crypto algorithm. The algorithm has since been attacked to the point where it is not considered useful.
The book is about her exploration of number theory, what happened when she worked with Baltimore, the crypto company, and where that took her. She is doubtless a bright star of mathematical talent, and, if this book is anything to go by, communicating that in a way that makes it easy to understand. It takes a tour through the mathematics, and suggests some good ways to go about teaching maths to keen but unknowlegable people, through the school competition circuit, and on, to the international competitions.
One disappointment, for me at least, is that she doesn’t describe the Cayley Purser algorithm itself, this might be modesty or because of its discredited status. She is very clear about her desire for the algorithm to be fully analysed before anyone got too excited, but the press got carried away with the potential.
But all in all, a very interesting book, written by an intelligent communicator. I have a lot of respect for Sarah now, Cayley Purser may have fallen, but she is worth keeping an eye on, there’ll be more good stuff from her in the future.
Who should read this book: anyone who is interested in cryptography, but doesn’t have a strong background in it, will appreciate the easy to understand mathematics, this isn’t to say the maths is easy, far from it, but the explanations are good. It will be a bit simplistic for the kinds of people who code crypto daily.