rfc-4770

vCard Extensions for Instant Messaging (IM)

C. Jennings, J. Reschke (Editor)

date2007-01 streamIETF wgnon working group statusPROPOSED STANDARD pages7 canonicalhttps://www.rfc-editor.org/rfc/rfc4770 doi10.17487/RFC4770 errataview

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. [STANDARDS-TRACK]

obsoleted by

rfc-6350 — vCard Format Specification

Extracted elements (9)

design-rationale §1

The URI type of an IMPP entry indicates which protocol may be used (e.g., 'sip' for SIP/SIMPLE, 'xmpp' for XMPP, 'im' or 'pres' for CPIM/CPP gateway), but this document intentionally does not define the URI types themselves, leaving that to the respective protocol specifications.

interoperability-note §3

The IMPP ABNF grammar extends the grammar found in RFC 2425 (Section 5.8.2) and RFC 2426 (Section 4), meaning conformant implementations must support the base vCard grammar in addition to the IMPP-specific extensions.

normative-requirement §1 SHOULD

A parameter should occur at most once in a given IMPP entry, though any combination of parameters is valid.

privacy-consideration §5

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.

privacy

protocol-element §2

The IMPP type supports a TYPE parameter that can specify intended use via values: PERSONAL or BUSINESS (purpose), HOME, WORK, or MOBILE (location), and PREF (preferred address, same semantics as TEL's PREF). Multiple TYPE values may be combined in a single IMPP entry.

protocol-element §1

The IMPP vCard type holds a single URI indicating the address of a service that provides instant messaging (IM), presence protocol (PP), or both. A given vCard may contain multiple IMPP entries, but each entry contains only one URI.

registry

registry §2

This document registers the IMPP type in the 'text/directory MIME Types' subregistry of the 'text/directory MIME Registrations' registry at IANA. Type encoding is 8bit; type value is a single URI.

registry

security-consideration §5

The IMPP extension does not introduce additional security issues beyond the existing vCard specification. However, presence information is often considered more sensitive than other address information, and systems storing or transferring vCards should carefully consider the privacy implications.

security, privacy

wire-format §3

The IMPP entry value is a single URI as defined by RFC 3986. The optional parameter is 'TYPE' followed by one or more comma-separated impp-type values. Values are case insensitive.