Journal of Digital Information Management Elena Pavlovna Stepanova, Igor Anatolyevich Kalmykov, Ekaterina Viktorovna Toporkova 14 2 2016 The aim of the work is to increase the reliability of the AES cipher by means of development and application of redundant codes of a polynomial residue number system (PRNS) that are able to correct the errors caused by failures.The known methods of counteracting failures do not take into account the specificities of the AES cipher, which leads to significant hardware costs. The problem can be solved through the use of error-correcting codes of a polynomial residue number system. However, it is impossible to use the known methods of search and correction of errors by the PRNS codes in the AES cipher. Therefore, the development of a method, the use of which will give the AES cipher the robustness property with respectto failures through the use of the PRNS codes, is a topical problem.