CAES Cryptosystem: Advanced Security Tests and Results

A robust and secure cryptosystem is an encrypting system that resists against all practical cryptanalysis methods such as statistical attacks, differential cryptanalysis and linear cryptanalysis. To prove the resistance against these attacks, the cryptosystem designer must carry out a list of robustness tests. Considering these constraints, we present in the current paper results of robustness and security tests conducted on the CAES (Cellular automata Encryption System) cryptosystem published in a previous article. The presented tests focus on randomness tests and on differential cryptanalysis. As results of these tests, we concluded that the cryptosystem CAES gives a pseudo-random output regardless the input. Also the differential attack needs huge number of chosen plaintexts which make it impractical.