Secret key cryptography with cellular automata

Summary form only given. The problem of designing symmetric key algorithms based upon cellular automata (CAs) is considered. As the basic cryptography scheme, the Vernam cipher is applied. The reliability of the Vernam cipher depends highly on the quality of random numbers used in the process of encryption. One dimensional, nonuniform CAs are considered as a generator of a high quality 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 are considered. The search of rules is performed using an evolutionary technique called cellular programming. As the result of collective behavior of a discovered set of CA rules, very high quality PNSs are generated. The quality of PNSs outperforms the quality of known one-dimensional CA-based PNS generators used for secret key cryptography. The extended set of CA rules, which was found makes the cryptography system much more resistant to breaking a cryptography key.