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PUBLICATIONS

Trustworthy Email

Published

Author(s)

Ramaswamy Chandramouli, Simson L. Garfinkel, J. S. Nightingale, Scott W. Rose

Abstract

This document gives recommendations and guidelines for enhancing trust in email. The primary audience includes enterprise email administrators, information security specialists and network managers. This guideline applies to federal IT systems and will also be useful for any small or medium sized organizations. Technologies recommended in support of core Simple Mail Transfer Protocol (SMTP) and the Domain Name System (DNS) include mechanisms for authenticating a sending domain (Sender Policy Framework (SPF), Domain Keys Identified Mail (DKIM) and Domain based Message Authentication, Reporting and Conformance (DMARC). Recommendations for email transmission security include Transport Layer Security (TLS) and associated certificate authentication protocols. Recommendations for email content security include the encryption and authentication of message content using S/MIME (Secure/Multipurpose Internet Mail Extensions) and associated certificate and key distribution protocols.
Citation
Special Publication (NIST SP) - 800-177
Report Number
800-177
NIST Pub Series
Special Publication (NIST SP)
Pub Type
NIST Pubs
Superceded By Publication
Trustworthy Email

Download Paper

DOI Link

Keywords

Cybersecurity, email, encryption, DNS
Networking, Information technology and Cybersecurity and privacy

Citation

Chandramouli, R. , Garfinkel, S. , Nightingale, J. and Rose, S. (2016), Trustworthy Email, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.SP.800-177 (Accessed October 9, 2025)

Issues

If you have any questions about this publication or are having problems accessing it, please contact [email protected].

Created September 6, 2016, Updated March 23, 2021
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