At present, there are several areas of joint application of a combinatorial analysis and a coding theory. On the one hand, the coding theory has a variety of applications for solving combinatorial problems of large dimension. On the other hand, combinatorial methods are actively being developed, used in various algorithms for encoding and decoding various types of information, which include text, graphics, sound, and a number of others. There are known encryption algorithms based on the Advanced Encryption Standard (AES). However, AES has limitations on certain specific multimedia requirements, which makes it necessary to develop other encryption algorithms. This article is devoted to the development of an algorithm for encrypting audio information using permutations. The proposed algorithm uses a permutation procedure to perform encryption of audio files using a stream encryption method. The algorithm uses a private key to perform encryption, depending on the key and data. Encryption of audio files was performed in five steps. In these steps, tables are replaced and various ways of rearranging audio data are used to perform lossless encryption. The algorithm developed by the authors was implemented and tested with different types of audio files of different sizes. Empirical analysis has shown that this algorithm is effective for encryption of medium or high quality audio files. Statistical analysis using histograms, peak signal-to-noise ratio, correlation and entropy showed that the algorithm is not vulnerable to statistical attacks if it is not used to encrypt low-quality audio files.
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