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Guideline for Implementing Cryptography in the Federal Government



Annabelle Lee


[Superseded by SP 800-21 Second edition (December 2005):] The purpose of this document is to provide guidance to Federal agencies on how to select cryptographic controls for protecting Sensitive Unclassified1 information. This document focuses on Federal standards documented in Federal Information Processing Standards Publications (FIPS PUBs) and the cryptographic modules and algorithms that are validated against these standards. However, to provide additional information, other standards organizations, (e.g., American National Standards Institute (ANSI) and International Organization for Standardization (ISO)) are briefly discussed.
Special Publication (NIST SP) - 800-21
Report Number


cryptographic algorithm, cryptographic hash function, cryptographic key, cryptographic module, digital signature, key establishment, key management, message authentication code


Lee, A. (1999), Guideline for Implementing Cryptography in the Federal Government, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 20, 2024)
Created November 1, 1999, Updated February 19, 2017