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Recommendation for Block Cipher Modes of Operation: The CMAC Mode for Authentication



Morris J. Dworkin


This Recommendation specifies a message authentication code (MAC) algorithm based on a symmetric key block cipher. This block cipher-based MAC algorithm, called CMAC, may be used to provide assurance of the authenticity and, hence, the integrity of binary data. [Supersedes SP 800-38B (May 2005):; See page ii for errata]
Special Publication (NIST SP) - 800-38B
Report Number


authentication, block cipher, cryptography, information security, integrity, message authentication code, mode of operation
Created October 6, 2016, Updated November 10, 2018