Acknowledgment using Message Disposition Notification

A Message Disposition Notification (MDN) is an acknowledgment file created by a receiver of a message.  The MDN  is sent to the message sender to notify of any success or failure of the received message.  The sender requests an MDN through the message itself or through other manual interaction.  When an MDN is requested via a message, the following conditions are required in the message:

• The message contains the following headers:
• “Disposition-Notification-To” header,
• “Return-Path” header, and
• “Message-ID” header.
• “Disposition-Notification-To” header contains only one distinct address.
• If more than one “Return-Path” header exists, only the first is selected.
• The address in the “Disposition-Notification-To” and the “Return-Path” header are equal (any phrase or routes are excluded from the comparison).

 Format of an MDN message

The MDN message is a content type “multipart/report” message and consists of 3 body parts in the following order.

1. A body part of human readable explanation of the MDN.
2. A body part of the reported errors.  This body part is a message of content type “message/disposition-notification”.
3. An optional body part containing the original message or some other text that helps in diagnosing the problem.