Abstract

This draft describes an extension to vCard to support Instant Messaging (IM) and Presence Protocol (PP) applications. It allows a URL that is associated with IM or PP to be specified inside of a vCard.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [3].

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 IMPP URLs. 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 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 URLs would be appropriate. A given vCard can have multiple IMPP entries but each entry can contain only one URL. Each IMPP entry can contain multiple parameters. Any combination of parameters is valid, though a parameter should occur at most once in a given IMPP entry.

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

2  IMPP Type Definition

To: ietf-mime-directory@imc.org

Subject: Registration of text/directory MIME type IMPP

Type name: IMPP

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

Type encoding: 8bit

Type value: A single URL.

Type special notes: The type can include the type parameter "TYPE" to specify an intended use for the URL. The TYPE parameter values can include:

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

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

An indication of some of the core capabilities of this instant messaging system. Values can be PRES, VIDEO, VOICE, TEXT, SMS, NUMERIC, and BEEP. PRES indicates the system supports some presence protocol. VIDEO, VOICE, and TEXT indicate the system supports voice, video, and text messaging respectively. SMS indicates short text messages. Short is not defined here but something like 160 octets may be a reasonable assumption. NUMERIC indicates that only numeric text messages are allowed. BEEP indicates that the only information the system can deliver is that a message was sent to the target user.

The value STORE indicates that the system can store messages for future delivery to intended the intended user.

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

3  Formal Grammar

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

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

 value      = uri

 impp-param = "TYPE" "=" impp-type *("," impp-type)
 
 impp-type  = "PERSONAL" / "BUSINESS" / ; purpose of communications 
              "HOME" / "WORK" / "MOBILE" / ; useful? 
              "VIDEO" / "VOICE" / "TEXT" /  ; core capabilities 
              "SMS" / "NUMERIC"  /  "BEEP"  / "PRES" ;  needed???
              "STORE" / ;  like MSG
              "PREF" / 
              iana-token / x-name; 
              ; Values are case insensitive 
 

4  Example

BEGIN:vCard
VERSION:3.0
FN:John Doe
IMPP;TYPE=personal,text,store,pref:im:john@example.com
END:vCard

5  IANA Considerations

section 2 forms the IANA registration.

6  Security Considerations

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

Normative References

Informational References