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The Third NIST Workshop on Block Cipher Modes of Operation 2023


NIST will host the Third NIST Workshop on Block Cipher Modes of Operation on October 3-4, 2023, at the National Cybersecurity Center of Excellence in Rockville, Maryland. NIST hosted the two previous modes workshops in conjunction with the development of the Advanced Encryption Standard (AES) in the early 2000s. 

This workshop will discuss how NIST can best address the limitations of the block cipher modes of operation (“modes,” for short) that are approved in the NIST Special Publication 800-38 Series, which will be documented in an initial public draft of NIST Internal Report (NIST IR) 8459, Report on the Block Cipher Modes of Operation in the NIST SP 800-38 Series. NIST is particularly interested in discussing the possibility of standardizing a tweakable wide block encryption technique that could support a large range of input lengths.  

Topics for discussion include:

  • The security and efficiency of current NIST modes
  • Additional security features (e.g., misuse-resistance, key commitment, etc.) that would be desirable in a new encryption technique
  • Case studies of encryption techniques for specific uses, such as storage and key wrapping
  • The security and efficiency of tweakable wide encryption techniques

NIST is also soliciting research and discussion papers, surveys, presentations, case studies, panel proposals, and participation from all interested parties. Submissions must be provided electronically in PDF format and sent to ciphermodes [at] (ciphermodes[at]nist[dot]gov). NIST will post the accepted papers and presentations on the workshop website, though no formal proceedings will be published.

Created March 10, 2023, Updated August 3, 2023