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Projects Block Cipher Techniques

Block Cipher Techniques

News and Updates

Decision to Revise SP 800-38B and 38C
April 10, 2025
After two public comment periods, NIST has decided to revise CMAC and CCM block cipher modes of operation specified in NIST Special Publications 800-38B and 800-38C.
Comment on the 2nd Draft of SP 800-38G Rev. 1
February 3, 2025
NIST has released a second public draft (2PD) of Special Publication (SP) 800-38Gr1 (Revision 1), Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption, for public comment. The public...
Proposal to Revise SP 800-38B and SP 800-38C
January 29, 2025
NIST's Crypto Publication Review Board is proposing to update Special Publications 800-38B, "The CMAC Mode for Authentication," and 800-38C, "The CCM Mode for Authentication and Confidentiality." Submit public comments...
Pre-Draft Call for Comments on GCM and GMAC
January 6, 2025
NIST requests public comments on whether to pursue one or both approaches  (GCM and GMAC).The public comment period closes on March 14, 2025. 
NIST Proposes to Standardize a Wider Variant of AES
December 24, 2024
NIST indicated its interest in vetting another Rijndael variant for approval: Rijndael with 256-bit blocks (i.e., Rijndael-256) with a single key size of 256-bits. NIST plans to develop a draft standard for Rijndael-256 over...
Report on 2024 Accordion Cipher Mode Workshop
November 21, 2024
NIST releases NIST IR 8537, NIST Workshop on the Requirements for an Accordion Cipher Mode 2024: Workshop Report.
Public Comments Requested on SP 800-38B and 800-38C
June 14, 2024
NIST is reviewing Special Publications 800-38B and 800-38C (CMAC and CCM block cipher modes) and requests public comments by September 13, 2024.
NIST to Revise Special Publication 800-38E
February 10, 2024
After two public comment periods, NIST has decided to revise SP 800-38E, "Recommendation for Block Cipher Modes of Operation: the XTS-AES Mode for Confidentiality on Storage Devices." 
Proposal to Revise SP 800-38D: GCM and GMAC Block Cipher Modes
August 23, 2023
NIST is proposing to revise NIST Special Publication 800-38D. Please submit public comments by October 9, 2023.
Decision to Revise NIST SP 800-38A
April 28, 2023
NIST has decided to revise SP 800-38A, "Recommendation for Block Cipher Modes of Operation: Methods and Techniques." Read this announcement for more details.
Proposal to Update NIST SP 800-38E
February 8, 2023
NIST is proposing to update Special Publication (SP) 800-38E, "Recommendation for Block Cipher Modes of Operation: the XTS-AES Mode for Confidentiality on Storage Devices." Please submit public comments by March 10, 2023.
Proposal to Update FIPS 197, The Advanced Encryption Standard
December 19, 2022
NIST's Crypto Publication Review Board is proposing to update FIPS 197, and public comments are due on the draft by February 13, 2023. No technical changes are being made to the standard. This announcement summarizes the...
NIST Requests Comments on Draft SP 800-38G Rev 1
February 28, 2019
NIST requests public comments on Draft SP 800-38G Revision 1, Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption. Comments are due by April 15, 2019.
Recent Cryptanalysis of FF3
April 12, 2017
Recent Cryptanalysis of FF3 - Special Publication 800-38G
NIST Released Special Publication 800-38G
March 29, 2016
NIST is pleased to announce the release of Special Publication 800-38G, Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption. This publication specifies and approves the FF1 and FF3...
Explanation of Changes to Draft SP 800-38G
June 27, 2014
Draft Special Publication 800-38G, Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption, released for public comment in July 2013, included three methods for format-preserving...
Draft Publication 800-38G
July 8, 2013
NIST is pleased to announce that Draft NIST Special Publication 800-38G, Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption, is available for public comment. Format-preserving...
NIST Special Publication 800-38F
December 21, 2012
NIST announces the release of Special Publication 800-38F, Recommendation for Block Cipher Modes of Operation: Methods for Key Wrapping. This publication describes cryptographic methods for the protection of the...

Contacts

Cipher Modes Technical Inquiries
ciphermodes@nist.gov

Dr. Morris Dworkin - NIST

Dr. Meltem Sönmez Turan - NIST

Dr. Nicky Mouha - Fedwriters

Topics

Security and Privacy: encryption, message authentication

Created January 04, 2017, Updated April 17, 2025