CIPID: Contact Information for the Presence Information Data Format
Extracted elements (25)
CIPID delivers only URIs (except for <display-name>) so that language and character set negotiation can occur within the URL-designated protocol rather than within the PIDF document itself.
CIPID elements describe the more static aspects of a presentity's presence information (e.g., homepage, icon, card), while RPID focuses on elements that change throughout the day; this separation allows CIPID information to be statically configured through a GUI.
CIPID can be used together with RPID (RFC 4480), future-status (RFC 4481), and other PIDF extensions in the same PIDF document, all extending the <person> or <tuple> elements in the presence data model (RFC 4479).
The XML 'xml:lang' attribute identifies language and script for <display-name>; if omitted, the default value is 'i-default' per BCP 18 (RFC 2277).
Each CIPID element may only appear at most once, unless otherwise noted (display-name allows multiple occurrences for different xml:lang values).
If identity verification of a referenced server's certificate fails (e.g., for https URIs per RFC 2818 section 3.1), the referenced content SHOULD NOT be retrieved and MUST NOT be used.
Presentities SHOULD provide icon images of sizes and aspect ratios that are appropriate for rendering as an icon.
Support for JPEG, PNG, and GIF formats for the <icon> element is REQUIRED of implementations.
Support for PNG and GIF image formats for the <map> element is REQUIRED.
Support for sounds coded as MPEG-2 Layer 3 (MP3) for the <sound> element is RECOMMENDED.
The <tuple> element is only extended with CIPID elements if the information describes a service referring to another person that is marked by an RPID <relationship> element with a value other than 'self'.
Use of UTF-8 is RECOMMENDED in environments where parser encoding support incompatibility exists.
The <card> element contains a URI pointing to a business card, such as in LDAP Data Interchange Format (LDIF) or vCard format, extending the <person> or <tuple> element in PIDF.
The <display-name> element contains the name that the presentity suggests should be shown by the watcher user interface. Multiple occurrences are allowed only if they carry different 'xml:lang' attributes to support multiple languages.
The <homepage> element provides a URI pointing to general information about the tuple or person, typically a web home page.
The <icon> element provides a URI pointing to an image representing the tuple or person for use in graphical user interfaces. Support for JPEG, PNG, and GIF formats is REQUIRED.
The <map> element provides a URI pointing to a map related to the tuple or person, which may be an image, an HTML client-side image map, or a GIS document (e.g., GML). Support for PNG and GIF image formats is REQUIRED.
The <sound> element provides a URI pointing to a sound object (e.g., MIDI or MP3) related to the tuple or person. Support for MPEG-2 Layer 3 (MP3) is RECOMMENDED; it may also be used to indicate name pronunciation.
This document registers the URN sub-namespace 'urn:ietf:params:xml:ns:pidf:cipid' for XML elements defining CIPID contact information presence extensions for PIDF.
This document registers the XML schema for 'urn:ietf:params:xml:ns:pidf:cipid' per the IETF XML Registry (BCP 81, RFC 3688).
Icons and other URIs in CIPID could function as a covert channel to convey messages to the watcher outside normal content monitoring; entities concerned about this may wish to prohibit URLs pointing to resources outside their domain.
Implementors must verify the identity in the referenced server's certificate against the URI (e.g., for https URIs, the domain must match the subjectAltName per RFC 2818 section 3.1); failure to verify MUST prevent use of the referenced content.
Watchers need to restrict which content types they render when pointed to by <icon>, <homepage>, <map>, <sound>, and <card> elements, to prevent rendering malicious content.
When a watcher accesses CIPID URIs, the presentity can deduce the watcher is currently active; a presence application may cache these objects to mitigate this privacy exposure, at the cost of potentially stale data.
All CIPID elements except <display-name> have type xs:anyURI; <display-name> has type xs:string. The schema namespace is 'urn:ietf:params:xml:ns:pidf:cipid' with elementFormDefault='qualified'.