An Information-Theoretic Treatment of Homophonic Substitution
نویسندگان
چکیده
The history of cryptology shows that most secret-key cipher systems that have been broken were broken by exploiting the departure of the plaintext statistics from those of a completely random sequence. The technique of "homophonic substitution" is an old technique for converting an actual plaintext sequence into a (more) random sequence. At EUROCRYPT '88, Günther [1] introduced an important generalization of homophonic substitution, which we will call "variable-length homophonic substitution". The purpose of this paper is to give an information-theoretic treatment of Günther's type of homophonic substitution.
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تاریخ انتشار 1989