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Status Report on the First Round of the Development of the Advanced Encryption Standard



James R. Nechvatal, Elaine B. Barker, Donna F. Dodson, Morris J. Dworkin, James Foti, E Roback


In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal Information, in furtherance of NIST's statutory responsibilities. In 1998, NIST announced the acceptance of fifteen candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST has reviewed the results of this research and selected five algorithms (MARS, RC6, Rijndael, Serpent and Twofish) as finalists. The research results and rationale for the selection of the finalists are documented in this report. The five finalists will be the subject of further study before the selection of one or more of these algorithms for inclusion in the Advanced Encryption Standard.
Journal of Research (NIST JRES) -


Advanced Encryption Standard (AES), cryptanalysis, cryptographic algorithms, cryptography, encryption


Nechvatal, J. , Barker, E. , Dodson, D. , Dworkin, M. , Foti, J. and Roback, E. (1999), Status Report on the First Round of the Development of the Advanced Encryption Standard, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 26, 2024)


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Created November 17, 1999, Updated February 19, 2017