#nist ### Block Cipher Modes A block cipher mode, or mode, for short, is an algorithm that **features the use of a symmetric key block cipher algorithm** to provide an information service, such as confidentiality or authentication. Currently, NIST has approved 14 modes of the [approved block ciphers](https://csrc.nist.gov/projects/block-cipher-techniques) in a series of special publications. As summarized on the [Current Modes](https://csrc.nist.gov/projects/block-cipher-techniques/bcm/current-modes) page, there are: - 8 confidentiality modes (ECB, CBC, OFB, CFB, CTR, XTS-AES, FF1, and FF3), - 1 authentication mode (CMAC), - 5 combined modes for confidentiality and authentication (CCM, GCM, KW, KWP, and TKW). Several other modes have been submitted to NIST for consideration; the submission documents are available at the [Modes Development](https://csrc.nist.gov/projects/block-cipher-techniques/bcm/modes-develoment) page. NIST welcomes public input on whether to approve any of these modes. Comments may be submitted to [[email protected]](mailto:[email protected]). #quantumsecurity