Cellular Programming and Symmetric Key Cryptography Systems

The problem of designing symmetric key cryptography algorithms based upon cellular automata (CAs) is considered. The reliability of the Vernam cipher used in the process of encryption highly depends on a quality of used random numbers. One dimensional, nonuniform CAs is considered as a generator of pseudorandom number sequences (PNSs). The quality of PNSs highly depends on a set of applied CA rules. To find such rules nonuniform CAs with two types of rules is considered. The search of rules is based on an evolutionary technique called cellular programming (CP). Resulting from the collective behavior of the discovered set of CA rules very high quality PNSs are generated. The quality of PNSs outperform the quality of known one dimensional CA-based PNS generators used in secret key cryptography. The extended set of CA rules which was found makes the cryptography system much more resistant on breaking a cryptography key.