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Recommendation for Block Cipher Modes of Operation: Methods for Format-Preserving Encryption



Morris J. Dworkin


This Recommendation specifies two methods, called FF1 and FF3, for format-preserving encryption. Both of these methods are modes of operation for an underlying, approved symmetric-key block cipher algorithm.
Special Publication (NIST SP) - 800-38G
Report Number


Block cipher, confidentiality, encryption, FF1, FF3, format-preserving encryption, information security, mode of operation
Created March 29, 2016, Updated November 10, 2018