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Transitions: Recommendation for Transitioning the Use of Cryptographic Algorithms and Key Lengths



Elaine B. Barker, Allen L. Roginsky


At the start of the 21st century, the National Institute of Standards and Technology (NIST) began the task of providing cryptographic key management guidance, which includes defining and implementing appropriate key management procedures, using algorithms that adequately protect sensitive information, and planning ahead for possible changes in the use of cryptography because of algorithm breaks or the availability of more powerful computing techniques. NIST Special Publication (SP) 800-57, Part 1 was the first document produced in this effort, and includes a general approach for transitioning from one algorithm or key length to another. This Recommendation (SP 800-131A) provides more specific guidance for transitions to the use of stronger cryptographic keys and more robust algorithms. [Supersedes SP 800-131A (January 2011):]
Special Publication (NIST SP) - 800-131A Rev 1
Report Number
800-131A Rev 1


cryptographic algorithm, digital signatures, encryption, hash function, key agreement, key derivation functions, key management, key transport, key wrapping, message authentication codes, random number generation, security strength, transition


Barker, E. and Roginsky, A. (2015), Transitions: Recommendation for Transitioning the Use of Cryptographic Algorithms and Key Lengths, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 20, 2024)


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Created November 6, 2015, Updated November 10, 2018