+++ /dev/null
-Notice-Requested-Upon-Delivery-To (NRUDT)
-D. J. Bernstein, djb@pobox.com
-19970201
-
-
-1. Introduction
-
- The UNIX sendmail program has for many years supported a
- Return-Receipt-To (RRT) header field that requests a notice of
- successful final delivery.
-
- Notice-Requested-Upon-Delivery-To (NRUDT) has the same basic
- function. The big difference is that RRT lists the sender's address,
- while NRUDT lists the recipient's address.
-
- This change is critical. RRT works poorly for messages to multiple
- recipients, because it requests a notice from every recipient. RRT in
- a message to a large mailing list produces a giant, usually
- unintentional, flood of mail. This problem is so severe that RRT has
- been disabled in recent versions of sendmail.
-
- NRUDT is designed to be adopted immediately, with minimal disruption,
- as a solution to the problems of RRT. Note that NRUDT is merely a
- request for notification; unlike the link-level Delivery Status
- Notification SMTP extension, NRUDT does not provide a guarantee of
- notification.
-
- NRUDT is supported by the qreceipt program in the qmail package.
-
-
-2. Syntax
-
- NRUDT is a field in the header of an RFC 822 mail message. It has the
- following syntax:
-
- "Notice-Requested-Upon-Delivery-To" ":" 1#address
-
- See RFC 822 for more information about header fields and addresses.
-
- NRUDT requests that, upon final delivery of the message to any of the
- specified addresses, the sender be notified. Note that more than one
- address can appear in a single NRUDT header field. Multiple NRUDT
- header fields should not appear in a single message.
-
-
-3. Response
-
- Upon successful final delivery of a message to any address listed in
- an NRUDT header field, the host performing delivery may, if desired,
- generate a success notice.
-
- The success notice is similar to a failure notice as described in RFC
- 1123. Its envelope sender is <>. Its envelope recipient is the
- envelope sender of the original message; however, if the envelope
- sender of the original message is <>, a success notice is not sent.
-
- The body of the success notice does not contain a copy of the
- original message, but it does indicate the Message-ID of the original
- message, as well as the relevant recipient address.
-
- A success notice may indicate delivery to several addresses. For
- example, given the following message:
-
- (envelope) from djb@silverton.berkeley.edu
- (envelope) to god@heaven.af.mil, angels@heaven.af.mil
- Date: 1 Jan 1996 21:43:34 GMT
- From: "D. J. Bernstein" <djb@silverton.berkeley.edu>
- Message-Id: <19960101214334.8529.qmail@silverton.berkeley.edu>
- Notice-Requested-Upon-Delivery-To: God <god@heaven.af.mil>,
- angels@heaven.af.mil (You Know Who You Are)
- ...
-
- a host may respond as follows:
-
- (envelope) from <> to djb@silverton.berkeley.edu
- Date: 1 Jan 1996 21:43:37 GMT
- From: DELIVERY NOTICE SYSTEM <MAILER-DAEMON@heaven.af.mil>
- To: djb@silverton.berkeley.edu
- Subject: success notice
-
- I delivered <19960101214334.8529.qmail@silverton.berkeley.edu>
- to the following local mailboxes:
-
- god@heaven.af.mil
- angels@heaven.af.mil
-
- Thanks for asking.
-
- However, a success notice is never merged with a failure notice.
~mdw / qmail / blobdiff