Nicolas Courtois

From Wikipedia, the free encyclopedia

Nicolas Courtois is a cryptographer, philosopher, film director, bird specialist, and amatuer magician. He is notable for creating (along with Josef Pieprzyk) the XSL attack. He works on cryptosystems and cryptographic attacks based on multivariate polynomial equations over finite fields. Courtois graduated from University of Paris VI: Pierre et Marie Curie, where he got his doctoral degree in cryptography.

The XSL attack is a method of cryptanalysis for block ciphers, which is claimed to have the potential for breaking the widely used Advanced Encryption Standard (AES) cipher — also known as Rijndael. If true, this would have serious and wide ranging implications. Meanwhile it has been widely shown that Courtois' method does not do any better than Faugere's F5 algorithm. The XSL was never taken too seriously by Algebrists.