NIST has released Special Publication 800-63-2, Electronic Authentication Guideline. This recommendation provides technical guidelines for Federal agencies implementing electronic authentication and is not intended to constrain the development or use of standards outside of this purpose. The recommendation covers remote authentication of users (such as employees, contractors, or private individuals) interacting with government IT systems over open networks. It defines technical requirements for each of four levels of assurance in the areas of identity proofing, registration, tokens, management processes, authentication protocols and related assertions. This publication supersedes NIST Special Publication 800-63-1. 
 
This revision is a limited update of Special Publication 800-63-1 and substantive changes are made only in section 5. Registration and Issuance Processes. The substantive changes made to section 5 are intended to facilitate the use of professional credentials in the identity proofing process, and to reduce the need to use postal mail to an address of record to issue credentials for level 3 remote registration.