Unraveling the MixColumns Operation of the AES Cipher Function

Resumo

The AES symmetric cryptographic algorithm is one of the most widely used nowadays. Its encryption process is quite complex and difficult to understand. Among encryption operations, one particularly is so much complicated to understand: the MixColumns. The goal of this work is to describe in detail, including an example, how AES MixColumns works. Thus, a bibliographical research was carried out to verify what the literature deals with regarding this subject in order to contribute positively to this work. As results and conclusion the objective of this article was reached out, by present all the steps involved in the operation of the AES algorithm MixColumn, explained each one of them in detail and even demonstrating a complete example of the state transformation process, which is the block of input bits of the process.