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SP 800-90C (Draft)

Recommendation for Random Bit Generator (RBG) Constructions (2nd Draft)

Date Published: April 2016
Comments Due: June 13, 2016 (public comment period is CLOSED)
Email Questions to: rbg_comments@nist.gov


Elaine Barker (NIST), John Kelsey (NIST)


NIST invites comments on the second draft of Special Publication (SP) 800-90C, Recommendation for Random Bit Generator (RBG) Constructions. This Recommendation specifies constructions for the implementation of RBGs. An RBG may be a deterministic random bit generator (DRBG) or a non-deterministic random bit generator (NRBG). The constructed RBGs consist of DRBG mechanisms, as specified in SP 800-90A, and entropy sources, as specified in SP 800-90B.

On May 2-3, 2016, NIST hosted a workshop on Random Number Generation to discuss the SP 800-90 series of documents--specifically, SP 800-90B and SP 800-90C.



non-deterministic random bit generator (NRBG); random number generator; randomness source  ; ; deterministic random bit generator (DRBG); construction; entropy source; entropy
Control Families

System and Communications Protection


Second Draft SP 800-90C

Supplemental Material:
Comment Template (word)

Document History:
09/05/12: SP 800-90C (Draft)
04/13/16: SP 800-90C (Draft)
09/07/22: SP 800-90C (Draft)


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random number generation