Today, NIST has published an update of Federal Information Processing Standards Publication (FIPS) 197, Advanced Encryption Standard (AES). This update makes no technical changes to the algorithm specified in the standard, which was originally published in 2001.
However, this update includes extensive editorial improvements to the original version, including the following:
- The front matter is modernized (e.g., a foreword and abstract are added).
- Terms and symbols are defined more comprehensively and consistently.
- Formatting/typesetting is improved in a variety of ways.
- Unnecessary formalism is removed.
- Diagrams for the three key schedules are included.
- Some references were updated, and additional references are provided.
The changes are documented in greater detail in Appendix D of the updated FIPS. NIST originally proposed to update FIPS 197 in this manner on December 19, 2022. The proposal included the release of a draft of the FIPS update for public comment, as well as a summary of the determination that no technical revisions were necessary. No public comments were received on the proposal nor the draft.
Previously, NIST had posted an initial call for comments on FIPS 197 on May 10, 2021, and received three sets of public comments. More details about this review are available from NIST’s Crypto Publication Review Project site.
