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Randomness Testing of the Advanced Encryption Standard Candidate Algorithms



Juan Soto


One of the criteria used to evaluate the Advanced Encryption Standard candidate algorithms was their demonstrated suitability as random number generators. That is, the evaluation of their output utilizing statistical tests should not provide any means by which to computationally distinguish them from a truly random source. This internal report lists several characteristics which an encryption algorithm exhibiting random behavior should possess, describes how the output for each candidate algorithm was evaluated for randomness, discusses what has been learned utilizing the NIST statistical tests, and finally provides an interpretation of the results.
NIST Interagency/Internal Report (NISTIR) - 6390
Report Number


Advanced Encryption Standard (AES), random number generators, randomness, statistical tests


Soto, J. (1999), Randomness Testing of the Advanced Encryption Standard Candidate Algorithms, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 22, 2024)


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Created September 1, 1999, Updated November 10, 2018