3.2 Module Overview

The Advanced Encryption Standard (AES) is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. It is compliant with the American FIPS (Federal Information Processing Standard) Publication 197 specification.

The AES supports all five confidentiality modes of operation for symmetrical key block cipher algorithms (as specified in the NIST Special Publication 800-38A Recommendation):

  • Electronic Code Book (ECB)

  • Cipher Block Chaining (CBC)

  • Output Feedback (OFB)

  • Cipher Feedback (CFB)

  • Counter (CTR)

Data transfers both to and from the AES module can occur using the peripheral DMA controller channels, thus minimizing processor intervention for large data buffer transfers.

As soon as the initialization vector, the input data and the key are configured, the encryption/decryption process may be started. Once the process has completed the encrypted/decrypted data can be read out via registers or through DMA channels.