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Validating the Correctness of Hardware Implementations of the NBS Data Encryption Standard



Jason Gait


This publication describes the design and operation of the NBS testbed that is used for the validation of hardware implementations of the Federal Information Processing Data Encryption Standard (DES). A particular implementation is verified if it correctly performs a set of 291 test cases that have been defined to exercise every basic element of the algorithm. As a further check on the correctness of the implementation, an extensive Monte-Carlo test is performed. This publication includes the full specification of the DES algorithm, a complete listing of the DES test set, and a detailed description of the interface to the testbed.
Special Publication (NIST SP) - 500-20
Report Number


communications security, computer security, cryptography, encryption standard, interface requirements, Monte-Carlo testing, testbed, test cases, validating correctness


Gait, J. (1980), Validating the Correctness of Hardware Implementations of the NBS Data Encryption Standard, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 24, 2024)


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Created September 1, 1980, Updated November 10, 2018