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SP 800-21 Second edition

Guideline for Implementing Cryptography in the Federal Government

Date Published: December 2005

Supersedes: SP 800-21 (11/01/1999)


Elaine Barker (NIST), William Barker (NIST), Annabelle Lee (NIST)



cryptographic algorithm; cryptographic hash function; cryptographic key; cryptographic module; digital signature; key establishment; key management; message authentication code
Control Families

Contingency Planning; Incident Response; Planning; System and Communications Protection; System and Services Acquisition


SP 800-21 Second edition (DOI)
Local Download

Supplemental Material:
None available

Document History:
12/01/05: SP 800-21 Second edition