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Search Search CSRC MENU Search Search Projects Publications Expand or Collapse Drafts for Public Comment All Public Drafts Final Pubs FIPS (standards) Special Publications (SP s ) IR (interagency/internal reports) CSWP (cybersecurity white papers) ITL Bulletins Project Descriptions Journal Articles Conference Papers Books Topics Expand or Collapse Security & Privacy Applications Technologies Sectors Laws & Regulations Activities & Products News & Updates Events Glossary About CSRC Expand or Collapse Computer Security Division Cryptographic Technology Software Security Group Hardware Security Group Security Engineering and Risk Management Applied Cybersecurity Division Cybersecurity and Privacy Applications National Cybersecurity Center of Excellence (NCCoE) National Initiative for Cybersecurity Education (NICE) Contact Us Information Technology Laboratory Computer Security Resource Center Publications NIST SP 800-177 Rev. 1 Trustworthy Email Share to Facebook Share to X Share to LinkedIn Share ia Email Documentation Topics Date Published: February 2019 Supersedes: SP 800-177 (09/07/2016) Author(s) Scott Rose (NIST) , Stephen Nightingale (NIST) , Simson Garfinkel (U.S. Census Bureau) , Ramaswamy Chandramouli (NIST) 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 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. 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 small or medium sized... See full 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 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. Hide full abstract Keywords 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) ; Email ; S/MIME Control Families None selected Documentation Publication: https://doi.org/10.6028/NIST.SP.800-177r1 Download URL Supplemental Material: High Assurance Domains project 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) Topics Security and Privacy general security & privacy , trustworthiness Technologies email Applications communications & wireless HEADQUARTERS 100 Bureau Drive Gaithersburg, MD 20899 X (link is external) facebook (link is external) linkedin (link is external) instagram (link is external) youtube (link is external) rss govdelivery (link is external) Want updates about CSRC and our publications? 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