摘要:This report is devoted to the comparative analysis of the lightweight NASH block encryption algorithm and the algorithm presented by USA National Security Agency in 2013 – SPECK. Their detailed description is given, the analysis is made. The task of the study is to investigate and analyze cryptographic encryption algorithms used in devices with limited capabilities such as microcontrollers. The study of lightweight encryption algorithms and their application for cybersecurity tasks is necessary to create the latest cryptographic systems aimed at preventing various types of attacks. The study revealed that the NASH block encryption algorithm showed more optimized performance, since the number of rounds of cipher execution is less than that Speck algorithm, which provides greater stability of algorithm with least number of executable rounds.