Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

NIST SP 800-90B (Initial Public Draft)

Recommendation for the Entropy Sources Used for Random Bit Generation

Date Published: August 2012
Comments Due: December 5, 2012 (public comment period is CLOSED)
Email Questions to:


Elaine Barker (NIST), John Kelsey (NIST)


NIST requests comments on two Draft publications for random bit generation: Draft SP 800-90B, Recommendation for the Entropy Sources Used for Random Bit Generation and Draft SP 800-90C, Recommendation for Random Bit Generator (RBG) Constructions. SP 800-90B specifies the design principles and requirements for the entropy sources used by Random Bit Generators, and thetests for the validation of entropy sources. A list of questions relating to SP 800-90B is also provided for reviewers. 

SP 800-90C specifies constructions for the implementation of random bit generators (RBGs). An RBG may be a deterministic random bit generator (DRBG) or a non-deterministic random bitgenerator (NRBG). The constructed RBGs consist of DRBG mechanisms as specified SP 800-90A and entropy sources as specified in SP 800-90B. 



deterministic random bit generator (DRBG); entropy; hash function; random number generator; noise source; entropy source; conditioning component
Control Families

System and Communications Protection


No Download Available

Supplemental Material:
None available

Document History:
09/05/12: SP 800-90B (Draft)
01/27/16: SP 800-90B (Draft)


Security and Privacy

random number generation