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Guidelines on Electronic Mail Security



Miles C. Tracy, Wayne Jansen, Karen A. Scarfone, Jason Butterfield


This document was developed in furtherance of NIST's statutory responsibilities under the Federal Information Security Management Act (FISMA) of 2002, Public Law 107-347. The purpose of the publication is to recommend security practices for designing, implementing, and operating email systems on public and private networks. It contains information on popular email encryption standards and other standards relating to email. It presents general information on securing mail servers? operating systems and specific guidance on securing mail server applications, protecting messages traversing servers, and securing access to mailboxes. It also provides information regarding email client security and mail server administration. [Supersedes SP 800-45 (September 2002):]
Special Publication (NIST SP) - 800-45 Ver 2
Report Number
800-45 Ver 2


email, electronic mail, FISMA


Tracy, M. , Jansen, W. , Scarfone, K. and Butterfield, J. (2007), Guidelines on Electronic Mail Security, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 13, 2024)
Created February 19, 2007, Updated October 12, 2021