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The Data Authentication Algorithm (DAA) is a former U.S. government standard for producing cryptographic message authentication codes. DAA is defined in FIPS PUB 113, which was withdrawn on September 1, 2008. The algorithm is not considered[by whom?] secure by today's standards. According to the standard, a code produced by the DAA is called a Data Authentication Code (DAC). The algorithm chain encrypts the data, with the last cipher block truncated and used as the DAC.