Abstract
Today, the improvement of methods for protecting information is an urgent task, therefore, the authors of the article are interested in using alternative methods of developing more robust and efficient public-key cryptosystems. Finite automata are taken as such a model. To systematize knowledge in the field of finite-state cryptography, it was decided to use ontology. This paper discusses the construction of an ontological model of finite-automaton cryptography. The proposed ontological model will have four main levels: the ontology of knowledge representation, the ontology of the top level, the domain ontology and practical ontologies. The methodology of conceptual maps was taken as the ontology of knowledge representation. The ontology of the top level contains basic information about cryptography and automata theory, the domain ontology describes directly the finite automaton cryptography. As an example of practical ontology, a public-key cryptosystem based on finite automata was considered. The presented ontology is modeled for the first time and gives a clear understanding of the use of finite automata in cryptography, systematizes the information obtained in the course of the research on this subject area, is a prerequisite in the further development of cryptosystems based on the theory of automata.