Exploring Mathematics 2007 at Royal Holloway, June 27th 2007
Professor Fred Piper
Title: "Codemakers versus Codebreakers: Who wins?"

If two people want to exchange confidential information then one option available to them is to use encryption which their 'enemies' then try to break.

Many commercial systems use encryption algorithms to protect valuable information. These algorithms are frequently international standards which are in the public domain but, so far as we know, have not been broken. In contrast to this, the successful activities of the codebreakers at Bletchley Park in World War 2 are well known.

In this short talk we will look at some of the problems facing the adversaries in this fascinating contest.