RFC 1894 (rfc1894) - Page 2 of 39

An Extensible Message Format for Delivery Status Notifications

RFC 1894             Delivery Status Notifications          January 1996


   experience, and are thus subject to change.

1. Introduction

   This memo defines a MIME [1] content-type for delivery status
   notifications (DSNs).  A DSN can be used to notify the sender of a
   message of any of several conditions:  failed delivery, delayed
   delivery, successful delivery, or the gatewaying of a message into an
   environment that may not support DSNs.  The "message/delivery-status"
   content-type defined herein is intended for use within the framework
   of the "multipart/report" content type defined in [2].

   This memo defines only the format of the notifications.  An extension
   to the Simple Message Transfer Protocol (SMTP) [3] to fully support
   such notifications is the subject of a separate memo [4].

1.1 Purposes

   The DSNs defined in this memo are expected to serve several purposes:

(a) Inform human beings of the status of message delivery processing, as
    well as the reasons for any delivery problems or outright failures,
    in a manner which is largely independent of human language;

(b) Allow mail user agents to keep track of the delivery status of
    messages sent, by associating returned DSNs with earlier message
    transmissions;

(c) Allow mailing list exploders to automatically maintain their
    subscriber lists when delivery attempts repeatedly fail;

(d) Convey delivery and non-delivery notifications resulting from
    attempts to deliver messages to "foreign" mail systems via a
    gateway;

(e) Allow "foreign" notifications to be tunneled through a MIME-capable
    message system and back into the original messaging system that
    issued the original notification, or even to a third messaging
    system;

(f) Allow language-independent, yet reasonably precise, indications of
    the reason for the failure of a message to be delivered (once status
    codes of sufficient precision are defined); and

(g) Provide sufficient information to remote MTA maintainers (via
    "trouble tickets") so that they can understand the nature of
    reported errors.  This feature is used in the case that failure to
    deliver a message is due to the malfunction of a remote MTA and the



Moore & Vaudreuil           Standards Track