RFC 4409 · DRAFT STANDARD · 2006

Message Submission for Mail

Overview

RFC 4409, “Message Submission for Mail”, is a Draft Standard document published in April 2006 by R. Gellens, J. Klensin. It obsoletes RFC 2476. It has been obsoleted by RFC 6409 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

This memo splits message submission from message relay, allowing each service to operate according to its own rules (for security, policy, etc.), and specifies what actions are to be taken by a submission server.

Message relay and final delivery are unaffected, and continue to use SMTP over port 25.

When conforming to this document, message submission uses the protocol specified here, normally over port 587.

This separation of function offers a number of benefits, including the ability to apply specific security or policy requirements. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Draft Standard” means

A historical maturity level (retired in 2011) that sat between Proposed Standard and Internet Standard and required multiple interoperable implementations.

Read this RFC

The canonical text of RFC 4409 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 2476
Obsoleted by
RFC 6409
Other RFCs from 2006

Who Is Online

In total there are 65 users online: 0 registered, 57 guests and 8 bots.

Most users ever online was 5,555 on 17 Jul 2026, 3:23 am.

Bots: AhrefsBot Applebot Baiduspider Bingbot Majestic Other Bot PetalBot SemrushBot

Users active in the past 15 minutes. Total registered members: 372