Key-dependent Advanced Encryption Standard

Abstract

Rijndael has been selected by the National Institute for Standards and Technology (NIST) as the Advanced Encryption Standard (AES). In compliance with Kerckhoffs's principle, and to preserve and promote interoperability, the design and internal operation of AES must remain open. However, we suggest that there is no need to retain the static nature of the design. Consequently, this research paper main objective is to introduce a dynamic algorithm, that determines the exact steps used for encrypting or decrypting payloads during execution time. This has been achieved by making AES parameters key dependent, rather than reuse fixed, pre-determined values.The result is an armored version of the AES that changes its internal design with almost every new encryption key. The proposed design is provided and analyzed in terms of security, implementation cost and possibility for further improvements.