Mail submission agent

A mail submission agent or MSA is a computer program or software agent which receives electronic mail messages from a mail user agent (MUA) and contacts an mail transfer agent (MTA) for delivery of the mail.

Many MTAs act as an MSA as well, but there are also programs that are specially designed as MSAs without full MTA functionality.

References

"Selected MARID-Related Terms and Acronyms." Techmoids.org. Accessed on February 24, 2005. "SMTP is not secure." Kasoft Central. Accessed on February 24, 2005.

MSA as an abbreviation can have other meanings: see the MSA disambiguation page.