HomeDocsIETF standardsRFCRFC 6400 — 6499
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Internet Engineering Task Force (IETF)
Request for Comments: 6473
Category: Standards Track
ISSN: 2070-1721
P. Saint-Andre
Cisco
December 2011

vCard KIND:application

Abstract

This document defines a value of "application" for the vCard KIND property so that vCards can be used to represent software applications.

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/rfc6473.

Copyright Notice

Copyright © 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 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 ....................................................2
   2. Meaning .........................................................2
   3. Example .........................................................4
   4. IANA Considerations .............................................4
   5. Security Considerations .........................................4
   6. Acknowledgements ................................................5
   7. References ......................................................5
      7.1. Normative References .......................................5
      7.2. Informative References .....................................5

1. Introduction

Version 4 of the vCard specification [RFC6350] defines a new KIND property to specify the type of entity that a vCard represents. During its work on the base vCard4 specification, the VCARDDAV Working Group defined values of "individual", "organization", "group", and "location" for the KIND property. The working group considered but then removed a value of "thing" to represent any type of physical entity, machine, software application, etc., with the expectation that such a value might be defined in a vCard extension. This document does not define a generic "thing" value but instead defines a more narrow "application" value so that vCards can be used to represent software applications.

2. Meaning

When the KIND property has a value of "application", the vCard represents a software application such as a server, an online service (e.g., a chat room), or an automated software bot. More formally, an "application" is functionally equivalent to the 'applicationProcess' object class used in the Lightweight Directory Access Protocol [RFC4519] as derived from the Open Systems Interconnection model [X.521] [X.200]. As one example of the "application" KIND, vCards are currently used in the Extensible Messaging and Presence Protocol [RFC6120] to represent instant messaging servers that are deployed on the network.

The properties included in an application's vCard apply to one of the following:

  • The application itself (e.g., the FN property might represent the friendly name of an application service, the URL property might represent a website that contains further information about the service, and the ADR, GEO, and TZ properties might represent the physical address, geographical location, and time zone of the machine where the service is hosted).
  • An organization or person that makes the application available on the network (e.g., the LOGO property might represent the corporate logo of a service provider).
  • A person or role that maintains the application (e.g., the TEL, EMAIL, and IMPP properties might represent ways to contact a server administrator).

When a property represents some aspect of the application itself, it makes no sense to include the "work" and "home" values of the TYPE parameter since software applications do not have work places and personal lives (see the definition of the TYPE parameter in Section 5.6 of [RFC6350]). When a property represents information about an individual associated with the application (e.g., an individual service administrator as opposed to a generic service administrator role or an associated organization), inclusion of the "work" and "home" values can be appropriate.

The following base properties make sense for vCards that represent software applications (this list is not exhaustive, and other properties might be applicable as well): 

   o  ADR
   o  EMAIL
   o  FN
   o  GEO
   o  IMPP
   o  KEY
   o  KIND
   o  LANG
   o  LOGO
   o  NOTE
   o  ORG
   o  PHOTO
   o  REV
   o  SOURCE
   o  TEL
   o  TZ
   o  URL

Although it might be desirable to define a more fine-grained taxonomy of applications (e.g., a KIND of "application" with a subtype of "server" or "IM server"), such a taxonomy is out of the scope of this document.

3. Example

The following example of an Extensible Messaging and Presence Protocol (XMPP) server is borrowed from [XEP-0292]. The XML representation of the vCard is described in [RFC6351], which allows for the use of the new "application" value using the "iana-token" production defined in [RFC6350]. 

   <vcard xmlns="urn:ietf:params:xml:ns:vcard-4.0">
     <fn><text>jabber.org IM service</text></fn>
     <url><uri>http://www.jabber.org/</uri></url>
     <lang>
       <parameters><pref><integer>1</integer></pref></parameters>
       <language-tag>en</language-tag>
     </lang>
     <email><text>xmpp@jabber.org</text></email>
     <impp><uri>xmpp:jabber.org</uri></impp>
     <logo><uri>http://www.jabber.org/images/logo.png</uri></logo>
     <geo><uri>geo:42.25,-91.05</uri></geo>
     <tz><text>America/Chicago</text></tz>
     <source><uri>xmpp:jabber.org?vcard</uri></source>
     <rev><timestamp>19990104T122100Z</timestamp></rev>
     <kind><text>application</text></kind>
   </vcard>

4. IANA Considerations

IANA has added "application" to the registry of property values for vCard4. In conformance with Section 10.2.6 of [RFC6350], the registration is as follows, where the reference is to RFC 6473. 

   Value:  application
   
   Purpose:  The entity represented by the vCard is a software
      application (e.g., a server, an online service such as a chat
      room, or an automated software bot).
   
   Conformance:  This value can be used with the KIND property.
   
   Example:  See Section 3 of RFC 6473.

5. Security Considerations

Use of vCards to represent software applications is not envisioned to introduce security considerations beyond those specified for vCards in general as described in [RFC6350].

6. Acknowledgements

Thanks to Cyrus Daboo, Barry Leiba, Kepeng Li, and Simon Perreault for their feedback.

7. References

7.1. Normative References

   [RFC6350]   Perreault, S., "vCard Format Specification", RFC 6350,
               August 2011.

7.2. Informative References

   [RFC4519]   Sciberras, A., "Lightweight Directory Access Protocol
               (LDAP): Schema for User Applications", RFC 4519,
               June 2006.
   
   [RFC6120]   Saint-Andre, P., "Extensible Messaging and Presence
               Protocol (XMPP): Core", RFC 6120, March 2011.
   
   [RFC6351]   Perreault, S., "xCard: vCard XML Representation",
               RFC 6351, August 2011.
   
   [X.200]     International Telecommunications Union, "Information
               Technology - Open Systems Interconnection - Basic
               Reference Model: The Basic Model", ITU-T Recommendation
               X.200, ISO Standard 7498-1, July 1994.
   
   [X.521]     International Telecommunications Union, "Information
               Technology - Open Systems Interconnection - The
               Directory: Selected Object Classes", ITU-T Recommendation
               X.521, ISO Standard 9594-7, November 2008.
   
   [XEP-0292]  Saint-Andre, P. and S. Mizzi, "vCard4 over XMPP", XSF
               XEP 0292, October 2011.

Author's Address

   Peter Saint-Andre
   Cisco
   1899 Wynkoop Street, Suite 600
   Denver, CO  80202
   USA
   
   Phone: +1-303-308-3282
   EMail: psaintan@cisco.com