Extensible Messaging and Presence Protocol (XMPP): Address Format
RFC 6122

Internet Engineering Task Force (IETF)                    P. Saint-Andre
Request for Comments: 6122                                         Cisco
Updates: 3920                                                 March 2011
Category: Standards Track
ISSN: 2070-1721

   Extensible Messaging and Presence Protocol (XMPP): Address Format

Abstract

   This document defines the format for addresses used in the Extensible
   Messaging and Presence Protocol (XMPP), including support for
   non-ASCII characters.  This document updates RFC 3920.

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/rfc6122.

Copyright Notice

   Copyright (c) 2011 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
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   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.

Saint-Andre                  Standards Track                    [Page 1]
RFC 6122                   XMPP Address Format                March 2011

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Addresses  . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     2.1.  Fundamentals . . . . . . . . . . . . . . . . . . . . . . .  4
     2.2.  Domainpart . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.3.  Localpart  . . . . . . . . . . . . . . . . . . . . . . . .  7
     2.4.  Resourcepart . . . . . . . . . . . . . . . . . . . . . . .  8
   3.  Internationalization Considerations  . . . . . . . . . . . . .  9
   4.  Security Considerations  . . . . . . . . . . . . . . . . . . .  9
     4.1.  Reuse of Stringprep  . . . . . . . . . . . . . . . . . . .  9
     4.2.  Reuse of Unicode . . . . . . . . . . . . . . . . . . . . .  9
     4.3.  Address Spoofing . . . . . . . . . . . . . . . . . . . . .  9
       4.3.1.  Address Forging  . . . . . . . . . . . . . . . . . . . 10
       4.3.2.  Address Mimicking  . . . . . . . . . . . . . . . . . . 10
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
     5.1.  Nodeprep Profile of Stringprep . . . . . . . . . . . . . . 13
     5.2.  Resourceprep Profile of Stringprep . . . . . . . . . . . . 14
   6.  Conformance Requirements . . . . . . . . . . . . . . . . . . . 14
   7.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
     7.1.  Normative References . . . . . . . . . . . . . . . . . . . 16
     7.2.  Informative References . . . . . . . . . . . . . . . . . . 17
   Appendix A.  Nodeprep  . . . . . . . . . . . . . . . . . . . . . . 19
     A.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . 19
     A.2.  Character Repertoire . . . . . . . . . . . . . . . . . . . 19
     A.3.  Mapping  . . . . . . . . . . . . . . . . . . . . . . . . . 19
     A.4.  Normalization  . . . . . . . . . . . . . . . . . . . . . . 19
     A.5.  Prohibited Output  . . . . . . . . . . . . . . . . . . . . 20
     A.6.  Bidirectional Characters . . . . . . . . . . . . . . . . . 20
     A.7.  Notes  . . . . . . . . . . . . . . . . . . . . . . . . . . 20
   Appendix B.  Resourceprep  . . . . . . . . . . . . . . . . . . . . 21
     B.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . 21
     B.2.  Character Repertoire . . . . . . . . . . . . . . . . . . . 22
     B.3.  Mapping  . . . . . . . . . . . . . . . . . . . . . . . . . 22
     B.4.  Normalization  . . . . . . . . . . . . . . . . . . . . . . 22
     B.5.  Prohibited Output  . . . . . . . . . . . . . . . . . . . . 22
     B.6.  Bidirectional Characters . . . . . . . . . . . . . . . . . 22
   Appendix C.  Differences from RFC 3920 . . . . . . . . . . . . . . 22
   Appendix D.  Acknowledgements  . . . . . . . . . . . . . . . . . . 23

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