Аннотация
The modified Dӧmӧsi's cryptosystem [1] is a stream cipher based on deterministic finite automata without outputs for encoding and decoding.This cryptosystem uses an additional control system to improve the performance to a better linear time without backtracking.This paper, we propose a nondeterministic variant of the cryptosystem, which allows to reduce the dependency of the key automata on a large size and on reversibility of automata.