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SP 800-177 Rev. 1 (Draft)

Trustworthy Email

Date Published: September 2017
Comments Due: October 13, 2017 (public comment period is CLOSED)
Email Questions to: sp800-177@nist.gov


Scott Rose (NIST), Stephen Nightingale (NIST), Simson Garfinkel (U.S. Census Bureau), Ramaswamy Chandramouli (NIST)


Trustworthy Email covers and gives recommendations for state of the art email security technologies to detect and prevent phishing and other malicious email messages. The guide was written for email administrators and for those developing security policies for an enterprise email infrastructure.

This revision was produced to include a new appendix with a FISMA overlay.  This overlay is for administrators of email systems that fall under FISMA and includes references to relevant guidance on specific FISMA controls and how they apply to various email system components.



Email; Simple Mail Transfer Protocol (SMTP); Transport Layer Security (TLS); Sender Policy Framework (SPF); Domain Keys Identified Mail (DKIM); Domain based Message Authentication, Reporting and Conformance (DMARC); Domain Name System (DNS) Authentication of Named Entities (DANE); S/MIME
Control Families

None selected


Draft SP 800-177 Rev. 1

Supplemental Material:
Comment template (xls)

Related NIST Publications:
SP 800-45 Version 2

Document History:
09/13/17: SP 800-177 Rev. 1 (Draft)
12/15/17: SP 800-177 Rev. 1 (Draft)
02/26/19: SP 800-177 Rev. 1 (Final)


Security and Privacy
general security & privacy

communications & wireless