* WGs marked with an * asterisk has had at least one new draft made available during the last 5 days

Xcon Status Pages

Centralized Conferencing (Concluded WG)
Rai Area: Alissa Cooper, Ben Campbell | 2003-Oct-07 — 2011-Sep-26 

2010-03-26 charter

Centralized Conferencing (xcon)


 Current Status: Active

     Alan Johnston <alan.b.johnston@gmail.com>
     Richard Barnes <rbarnes@bbn.com>

 Real-time Applications and Infrastructure Area Directors:
     Gonzalo Camarillo <gonzalo.camarillo@ericsson.com>
     Robert Sparks <rjsparks@nostrum.com>

 Real-time Applications and Infrastructure Area Advisor:
     Robert Sparks <rjsparks@nostrum.com>

 Mailing Lists:
     General Discussion: xcon@ietf.org
     To Subscribe:       https://www.ietf.org/mailman/listinfo/xcon
     Archive:            http://www.ietf.org/mail-archive/web/xcon/index.html

Description of Working Group:

  The focus of this working group is to develop a standardized suite of
  protocols for tightly-coupled multimedia conferences, where strong
  security and authorization requirements are integral to the solution.
  Tightly-coupled conferences have a central point of control and
  authorization (known as a focus) so they can enforce specific media and
  membership relationships, and provide an accurate roster of
  participants. The media mixing or combining function of a tightly-
  coupled conference need not be performed centrally, however.

  The scope of this effort is intentionally more narrow than previous
  attempts to standardize conferencing (e.g. centralized control), and is
  intended to enable interoperability in a commercial environment which
  already has a number of non-standard implementations using some of the

  Privacy, security, and authorization mechanisms are integral to the
  solution generated by the working group. This includes allowing
  participants to be invisible to all but the conference owner, or to be
  visible but participate anonymously with respect to some or all of
  the other participants.

  Authorization rules allow for participants and non-participants
  to have roles (ex: speaker, moderator, owner), and to be otherwise
  authorized to perform membership and media manipulation for or on
  behalf of other participants. In order to preserve these properties,
  the protocols used will require implementation of channel security
  and authentication services.

  Due to the centralized architecture of the WG, XCON's mechanisms will
  place requirements on the signaling protocol used between the focus
  and the participants. At a high level, the signaling protocol must be
  able to establish, tear down, modify, and perform call control
  operations on multimedia streams, including voice, video, and instant
  messaging, in both a centralized and distributed mixing architecture.
  SIP will be the reference session signaling protocol used for examples;
  however, none of the XCON solutions themselves will be signaling
  protocols, nor will XCON extend existing signaling protocols. Other
  signaling protocols than SIP may be used between the focus and
  participants, including non-IETF protocols, but the requirements and
  possible extensions needed for other signaling protocols to utilize the
  full functionality of the XCON architecture is outside the scope of

  The deliverables for the group will be:
  - A mechanism for membership and authorization control
  - A mechanism to manipulate and describe media "mixing" or "topology"
    for multiple media types (audio, video, text)
  - A mechanism for notification of conference related events/changes
    (for example a floor change)
  - A basic floor control protocol

  The initial set of protocols will be developed for use in unicast media
  conferences. The working group will perform a second round of work to
  enhance the set of protocols as necessary for use with multicast media
  after their initial publication.

  The following items are specifically out-of-scope:
  - Voting
  - Fully distributed conferences
  - Loosely-coupled conferences (no central point of control)
  - Far-end device control
  - Protocol used between the conference controller and the mixer(s)
  - Capabilities negotiation of the mixer(s)
  - Master-slave cascaded conferences

  The working group will coordinate closely with the SIPPING and
  MMUSIC working groups. In addition the working group will cooperate
  with other groups as needed, including SIP, MSEC, AVT, and the W3C
  SMIL working groups. In addition, the working group will consider
  a number of existing drafts as input to the working group.

Goals and Milestones:
  Done     - Submit Requirements for Basic Floor Control for publication as Informational
  Done     - Submit Conferencing Scenarios document for publication as Informational
  Done     - Submit Basic Floor Control Protocol for publication as PS
  Done     - Submit Framework for publication as PS
  Done     - Submit Event Notification Package for publication as PS
  Aug 2009 - Submit Conference Data Model for publication as PS
  Aug 2009 - Submit Conference Control Protocol for publication as PS
  Apr 2010 - Submit Conferencing Call Flows Document for publication as Informational

All charter page changes, including changes to draft-list, rfc-list and milestones:

Generated from PyHt script /wg/xcon/charters.pyht Latest update: 24 Oct 2012 16:51 GMT -