DEVELOPMENT OF A MODEL FOR APPLYING CORRELATION CRYPTANALYSIS TO FILTERING GENERATORS

Abstract

This article is devoted to problems of cryptanalysis. Cryptographic analysis results, got from using of correlation cryptanalysis method to algorithm of the flow crypto operation, founded on register of the shift with feedback, were presented in work. For estimation of the flow crypto operation algorithm’s crypto stability by correlation cryptanalysis method, number of important tasks was defined, purposes and problems of the study were determined. As a result of defined tasks decision, mathematical model and software of correlation cryptanalysis method to flow crypto operation to filtering LILI-128 – were developed.  Results has shown, that characteristic of correlation immunity of filtering functions, used in filtering generator, provide stability to correlation cryptanalysis method. Execution with big probability of stat-analogical function, defined in process of cryptanalysis, raises the efficiency of cryptanalysis. Proposed mathematical model and software can be used for estimation of stability of the algorithm of the flow crypto operation to correlation cryptanalysis, as well as in scholastic purpose.