Network Working Group Request for Comments: 4409 Obsoletes: 2476 Category: Standards Track

R. Gellens QUALCOMM J. Klensin April 2006

Message Submission for Mail Status of This Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2006). 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.

Gellens & Klensin

Standards Track

[Page 1]

RFC 4409

Message Submission for Mail

April 2006

Table of Contents 1. Introduction ....................................................3 2. Document Information ............................................4 2.1. Definitions of Terms Used in This Memo .....................4 2.2. Conventions Used in This Document ..........................5 3. Message Submission ..............................................5 3.1. Submission Identification ..................................5 3.2. Message Rejection and Bouncing .............................5 3.3. Authorized Submission ......................................6 4. Mandatory Actions ...............................................7 4.1. General Submission Rejection Code ..........................7 4.2. Ensure All Domains Are Fully-Qualified