On some developments in cryptography and their applications to computer science

Abstract

This paper presents a discussion and summary of results obtained jointly with K.Culik [1] and M.Nivat [2].

The idea of public key systems as applicable to information systems is reviewed. The development of information systems based on the new concept of encryption triple is outlined. Although the construction of encryption triples using number-theoretic tools is possible, systems of encryption triples obtained that way do not possess all properties desirable for designing information systems. As first step towards an alternative approach, regular bijections i.e. bijections definable by a-transducers are investigated, and a complete characterization of such bijections is given.