Conference Event Package Data Format Extension for Centralized Conferencing (XCON)

Abstract

This document specifies the notification mechanism for XCON (centralized conferencing). This mechanism reuses the SIP (Session Initiation Protocol) event package for conference state. Additionally, the notification mechanism includes support for the XCON data model and for partial notifications.

Multi-party Chat Using the Message Session Relay Protocol (MSRP)

“…This would typically be the mechanisms defined in "A Session Initiation Protocol (SIP) Event Package for Conference State" [RFC4575] or "Conference Event Package Data Format Extension for Centralized Conferencing (XCON)" [RFC6502].…”

“…It is RECOMMENDED that conference foci and endpoints support RFC 6502 [RFC6502] for providing information regarding the conference and, in particular, supplying information of the roster of the conference. It is also RECOMMENDED that conference foci and endpoints support RFC 6501 [RFC6501], which extends the <user> element originally specified in RFC 4575 [RFC4575] with a new 'nickname' attribute.…”

Interworking between the Session Initiation Protocol (SIP) and the Extensible Messaging and Presence Protocol (XMPP): Groupchat

“…As mentioned in [RFC7701], the joining user will typically also subscribe to a conference event package (see [RFC4575] and [RFC6502]) at the focus. Although such a subscription is not required by [RFC7701] in practice the temporary and context-dependent presence subscriptions and room rosters involved in joining an XMPP MUC room are best mapped to the conference event package.…”

Indication of Conference Focus Support for the Centralized Conferencing Manipulation Protocol (CCMP)

“…This approach would be suitable for a UA, e.g., an application server that acts as a Back-to-Back User Agent (B2BUA), that is interested in discovering that a conference focus supports CCMP but does not use the XCON conference event package [RFC6502]. In this case, the application could use the OPTIONS request and discover CCMP support from the response.…”

“…The advantage of this approach is the ability to discover that a conference focus supports CCMP, without subscribing to the XCON event package [RFC6502]. The disadvantage is the need, in some cases, for an extra request, i.e., an additional OPTIONS request, to discover that a conference focus supports CCMP.…”