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Report on the Development of the Advanced Encryption Standard (AES)



James R. Nechvatal, Elaine B. Barker, Lawrence E. Bassham, William E. Burr, 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 reviewed the results of this preliminary research and selected MARS, RC6 , Rijndael, Serpent and Twofish as finalists. Having reviewed further public analysis of the finalists, NIST has made a selection, which will be proposed for inclusion in the Advanced Encryption Standard (AES). The research results and rationale for this selection are documented in this report.
Journal of Research (NIST JRES) -
106 No. 3


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


Nechvatal, J. , Barker, E. , Bassham, L. , Burr, W. , Dworkin, M. , Foti, J. and Roback, E. (2001), Report on the Development of the Advanced Encryption Standard (AES), Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 25, 2024)


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Created June 1, 2001, Updated February 17, 2017