Network Working Group                                        C. Jennings
Request for Comments: 4770                                 Cisco Systems
Category: Standards Track                                J. Reschke, Ed.
                                                              greenbytes
                                                            January 2007


              vCard Extensions for Instant Messaging (IM)

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The IETF Trust (2007).

Abstract

   This document describes an extension to vCard to support Instant
   Messaging (IM) and Presence Protocol (PP) applications.  IM and PP
   are becoming increasingly common ways of communicating, and users
   want to save this contact information in their address books.  It
   allows a URI that is associated with IM or PP to be specified inside
   a vCard.

Table of Contents

   1. Overview ........................................................2
   2. IANA Considerations .............................................3
   3. Formal Grammar ..................................................4
   4. Example .........................................................4
   5. Security Considerations .........................................4
   6. Acknowledgments .................................................4
   7. References ......................................................5
      7.1. Normative References .......................................5
      7.2. Informational References ...................................5










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RFC 4770                       IMPP vCard                   January 2007


1.  Overview

   As more and more people use various instant messaging (IM) and
   presence protocol (PP) applications, it becomes important for them to
   be able to share this contact address information, along with the
   rest of their contact information.  RFC 2425 [1] and RFC 2426 [2]
   define a standard format for this information, which is referred to
   as vCard.  This document defines a new type in a vCard for
   representing instant IM and PP URIs.  It is very similar to existing
   types for representing email address and telephone contact
   information.

   The type entry to hold this new contact information is an IMPP type.
   The IMPP entry has a single URI (see RFC 3986 [3]) that indicates the
   address of a service that provides IM, PP, or both.  Also defined are
   some parameters that give hints as to when certain URIs would be
   appropriate.  A given vCard can have multiple IMPP entries, but each
   entry can contain only one URI.  Each IMPP entry can contain multiple
   parameters.  Any combination of parameters is valid, although a
   parameter should occur, at most, once in a given IMPP entry.

   The type of URI indicates what protocols might be usable for
   accessing it, but this document does not define any of the types.
   For example, a URI type of

   o  "sip" [5] indicates to use SIP/SIMPLE,
   o  "xmpp" [6] indicates to use XMPP,
   o  "irc" indicates to use IRC,
   o  "ymsgr" indicates to use yahoo,
   o  "msn" might indicate to use Microsoft messenger,
   o  "aim" indicates to use AOL, and
   o  "im" [7] or "pres" [8] indicates that a CPIM or CPP gateway should
      be used.

   The normative definition of this new vCard type is given in Section
   2, and an informational ABNF is provided in Section 3.















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RFC 4770                       IMPP vCard                   January 2007


2.  IANA Considerations

   The required email to define this extension (as defined in RFC 2425
   [1]) was sent on October 29, 2004, to the ietf-mime-direct@imc.org
   mailing list with the subject "Registration of text/directory MIME
   type IMPP" (see <http://www.imc.org/ietf-mime-direct/mail-
   archive/msg00068.html>).

   This specification updates the "text/directory MIME Types"
   subregistry in the "text/directory MIME Registrations" registry at
   http://www.iana.org/assignments/text-directory-registrations with the
   following information:

   Type name: IMPP

   Type purpose: To specify the URI for instant messaging and presence
   protocol communications with the object the vCard represents.

   Type encoding: 8bit

   Type value: A single URI.  The type of the URI indicates the protocol
   that can be used for this contact.

   Type special notes: The type may include the type parameter "TYPE" to
   specify an intended use for the URI.  The TYPE parameter values
   include one or more of the following:

   o  An indication of the type of communication for which this URI is
      appropriate.  This can be a value of PERSONAL or BUSINESS.

   o  An indication of the location of a device associated with this
      URI.  Values can be HOME, WORK, or MOBILE.

   o  The value PREF indicates this is a preferred address and has the
      same semantics as the PREF value in a TEL type.

   Additional information can be found in RFC 4770.

   Intended usage: COMMON












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3.  Formal Grammar

   The following ABNF grammar [4] extends the grammar found in RFC 2425
   [1] (Section 5.8.2) and RFC 2426 [2] (Section 4).

   ;For name="IMPP"
    param      = impp-param ; Only impp parameters are allowed

    value      = URI
                 ; URI defined in Section 3 of [3]

    impp-param = "TYPE" "=" impp-type *("," impp-type)

    impp-type  = "PERSONAL" / "BUSINESS" / ; purpose of communications
                 "HOME" / "WORK" / "MOBILE" /
                 "PREF" /
                 iana-token / x-name;
                 ; Values are case insensitive

4.  Example

   BEGIN:vCard
   VERSION:3.0
   FN:Alice Doe
   IMPP;TYPE=personal,pref:im:alice@example.com
   END:vCard

5.  Security Considerations

   This does not introduce additional security issues beyond the current
   vCard specification.  It is worth noting that many people consider
   their presence information more sensitive than other address
   information.  Any system that stores or transfers vCards needs to
   carefully consider the privacy issues around this information.

6.  Acknowledgments

   Thanks to Brian Carpenter, Lars Eggert, Ted Hardie, Paul Hoffman, Sam
   Roberts, and Pekka Pessi for their comments.












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7.  References

7.1.  Normative References


   [1]  Howes, T., Smith, M., and F. Dawson, "A MIME Content-Type for
        Directory Information", RFC 2425, September 1998.

   [2]  Dawson, F. and T. Howes, "vCard MIME Directory Profile", RFC
        2426, September 1998.

   [3]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
        Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986,
        January 2005.

   [4]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
        Specifications: ABNF", RFC 4234, October 2005.

7.2.  Informational References

   [5]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
        Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP:
        Session Initiation Protocol", RFC 3261, June 2002.

   [6]  Saint-Andre, P., "Internationalized Resource Identifiers (IRIs)
        and Uniform Resource Identifiers (URIs) for the Extensible
        Messaging and Presence Protocol (XMPP)", RFC 4622, July 2006.

   [7]  Peterson, J., "Common Profile for Instant Messaging (CPIM)", RFC
        3860, August 2004.

   [8]  Peterson, J., "Common Profile for Presence (CPP)", RFC 3859,
        August 2004.


















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Authors' Addresses

   Cullen Jennings
   Cisco Systems
   170 West Tasman Drive
   MS: SJC-21/2
   San Jose, CA  95134
   USA

   Phone: +1 408 902-3341
   EMail: fluffy@cisco.com


   Julian F. Reschke (editor)
   greenbytes GmbH
   Hafenweg 16
   Muenster, NW  48155
   Germany

   Phone: +49 251 2807760
   EMail: julian.reschke@greenbytes.de






























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RFC 4770                       IMPP vCard                   January 2007


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   Copyright (C) The IETF Trust (2007).

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Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.






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