Entropy Method for Assessing the Strength of Encryption Algorithms

The development of cryptology is closely related to the improvement of the evaluation methodology of block ciphers, which have become widespread in the protocols for ensuring the security of banking information and other communication systems and networks due to their high productivity and low complexity of implementation. In addition to ensuring confidentiality (data protection during transmission from passive attacks), symmetric algorithms are used to ensure integrity based on message authentication codes (MAC codes) and hash functions, as components of an electronic digital signature, generation of pseudo-random post-sequences as part of authentication protocols etc. For the comparative evaluation of the efficiency (cryptoresistance) of symmetric crypto-algorithms, as a rule, methods of linear and differential cryptanalysis are used. Comparison of security mechanisms based on algorithms of traditional cryptography, public key cryptography, and hybrid cryptosystems is possible on the basis of a comprehensive indicator that takes into account the criteria of cryptoresistance, speed of cryptographic transformations, transparency of encryption procedures for the user, distribution of key sequences, investments in information security, which does not allow without significant time and economic costs to determine their effectiveness. That is why it is proposed to use express analysis based on the entropy method to assess the stability of crypto-algorithms of various models of crypto-systems. Most of the methods for assessing the quality of encryption mechanisms are based on a complex mathematical apparatus, and obtaining and interpreting the results requires special knowledge and additional funds. The proposed express analysis allows to intuitively compare not only the stability of various crypto-algorithms (crypto systems), but also their software implementation, without significant computing and energy costs.