Internationalized Delivery Status and Disposition Notifications
RFC 6533

Internet Engineering Task Force (IETF)                    T. Hansen, Ed.
Request for Comments: 6533                             AT&T Laboratories
Obsoletes: 5337                                                C. Newman
Updates: 3461, 3464, 3798, 6522                                   Oracle
Category: Standards Track                                    A. Melnikov
ISSN: 2070-1721                                                Isode Ltd
                                                           February 2012

    Internationalized Delivery Status and Disposition Notifications

Abstract

   Delivery status notifications (DSNs) are critical to the correct
   operation of an email system.  However, the existing Draft Standards
   (RFC 3461, RFC 3464, RFC 6522) are presently limited to ASCII text in
   the machine-readable portions of the protocol.  This specification
   adds a new address type for international email addresses so an
   original recipient address with non-ASCII characters can be correctly
   preserved even after downgrading.  This also provides updated content
   return media types for delivery status notifications and message
   disposition notifications to support use of the new address type.

   This document extends RFC 3461, RFC 3464, RFC 3798, and RFC 6522.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6533.

Hansen, et al.               Standards Track                    [Page 1]
RFC 6533             Internationalized DSN and MDNs        February 2012

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Conventions Used in This Document  . . . . . . . . . . . . . .  3
   3.  UTF-8 Address Type . . . . . . . . . . . . . . . . . . . . . .  3
   4.  UTF-8 Delivery Status Notifications  . . . . . . . . . . . . .  6
     4.1.  The message/global-delivery-status Media Type  . . . . . .  6
     4.2.  The message/global Media Type  . . . . . . . . . . . . . .  8
     4.3.  The message/global-headers Media Type  . . . . . . . . . .  8
     4.4.  Using These Media Types with multipart/report  . . . . . .  8
     4.5.  Additional Requirements on SMTP Servers  . . . . . . . . .  9
   5.  UTF-8 Message Disposition Notifications  . . . . . . . . . . .  9
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 10
     6.1.  UTF-8 Mail Address Type Registration . . . . . . . . . . . 10
     6.2.  Update to 'smtp' Diagnostic Type Registration  . . . . . . 11
     6.3.  message/global-headers . . . . . . . . . . . . . . . . . . 11
     6.4.  message/global-delivery-status . . . . . . . . . . . . . . 12
     6.5.  message/global-disposition-notification  . . . . . . . . . 14
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 15
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 16
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 17
   Appendix A.  Changes since RFC 5337  . . . . . . . . . . . . . . . 18
   Appendix B.  Acknowledgements  . . . . . . . . . . . . . . . . . . 18

Hansen, et al.               Standards Track                    [Page 2]
RFC 6533             Internationalized DSN and MDNs        February 2012

1.  Introduction

   When an email message is transmitted using the SMTPUTF8 [RFC6531]
   extension and Internationalized Email Headers [RFC6532], it is
   sometimes necessary to return that message or generate a Message
   Disposition Notification (MDN) [RFC3798].  As a message sent to