XCON                                                             O. Novo
Internet-Draft                                              G. Camarillo
Intended status: Standards Track                                Ericsson
Expires: April 18, 2011                                        D. Morgan
                                                    Fidelity Investments
                                                           J. Urpalainen
                                                                   Nokia
                                                            Oct 15, 2010


 Conference Information Data Model for Centralized Conferencing (XCON)
                draft-ietf-xcon-common-data-model-20.txt

Abstract

   This document defines an Extensible Markup Language (XML)-based
   conference information data model for centralized conferencing
   (XCON).  A conference information data model is designed to convey
   information about the conference and about participation in the
   conference.  The conference information data model defined in this
   document constitutes an extension of the data format specified in the
   Session Initiation Protocol (SIP) Event Package for Conference State.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 18, 2011.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of



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   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

































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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  7
   3.  Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .  7
     3.1.  Data Model Format  . . . . . . . . . . . . . . . . . . . .  7
     3.2.  Data Model Namespace . . . . . . . . . . . . . . . . . . .  7
     3.3.  The Conference Object Identifier . . . . . . . . . . . . .  8
       3.3.1.  Conference Object URI Definition . . . . . . . . . . . 10
       3.3.2.  Normalization and Conference Object URI Comparison . . 10
     3.4.  Data Model Structure . . . . . . . . . . . . . . . . . . . 10
   4.  Data Model Definition  . . . . . . . . . . . . . . . . . . . . 11
     4.1.  <conference-info>  . . . . . . . . . . . . . . . . . . . . 15
     4.2.  <conference-description> . . . . . . . . . . . . . . . . . 15
       4.2.1.  <language> . . . . . . . . . . . . . . . . . . . . . . 15
       4.2.2.  <display-text> . . . . . . . . . . . . . . . . . . . . 15
       4.2.3.  <subject>  . . . . . . . . . . . . . . . . . . . . . . 16
       4.2.4.  <free-text>  . . . . . . . . . . . . . . . . . . . . . 16
       4.2.5.  <keywords> . . . . . . . . . . . . . . . . . . . . . . 16
       4.2.6.  <allow-sidebars> . . . . . . . . . . . . . . . . . . . 16
       4.2.7.  <cloning-parent> . . . . . . . . . . . . . . . . . . . 16
       4.2.8.  <sidebar-parent> . . . . . . . . . . . . . . . . . . . 16
       4.2.9.  <conference-time>  . . . . . . . . . . . . . . . . . . 16
       4.2.10. <conf-uris>  . . . . . . . . . . . . . . . . . . . . . 18
       4.2.11. <service-uris> . . . . . . . . . . . . . . . . . . . . 18
       4.2.12. <maximum-user-count> . . . . . . . . . . . . . . . . . 18
       4.2.13. <available-media>  . . . . . . . . . . . . . . . . . . 18
     4.3.  <host-info>  . . . . . . . . . . . . . . . . . . . . . . . 20
     4.4.  <conference-state> . . . . . . . . . . . . . . . . . . . . 21
       4.4.1.  <allow-conference-event-subscription>  . . . . . . . . 21
       4.4.2.  <user-count> . . . . . . . . . . . . . . . . . . . . . 21
       4.4.3.  <active> . . . . . . . . . . . . . . . . . . . . . . . 21
       4.4.4.  <locked> . . . . . . . . . . . . . . . . . . . . . . . 21
     4.5.  <floor-information>  . . . . . . . . . . . . . . . . . . . 21
       4.5.1.  <conference-ID>  . . . . . . . . . . . . . . . . . . . 21
       4.5.2.  <allow-floor-events> . . . . . . . . . . . . . . . . . 22
       4.5.3.  <floor-request-handling> . . . . . . . . . . . . . . . 22
       4.5.4.  <conference-floor-policy>  . . . . . . . . . . . . . . 22
     4.6.  <users>  . . . . . . . . . . . . . . . . . . . . . . . . . 23
       4.6.1.  <join-handling>  . . . . . . . . . . . . . . . . . . . 23
       4.6.2.  <user-admission-policy>  . . . . . . . . . . . . . . . 24
       4.6.3.  <allowed-users-list> . . . . . . . . . . . . . . . . . 24
       4.6.4.  <deny-users-list>  . . . . . . . . . . . . . . . . . . 25
       4.6.5.  <user> and Its <user> Sub-elements . . . . . . . . . . 26
         4.6.5.1.  <display-text> . . . . . . . . . . . . . . . . . . 27
         4.6.5.2.  <associated-aors>  . . . . . . . . . . . . . . . . 27
         4.6.5.3.  <provide-anonymity>  . . . . . . . . . . . . . . . 27
         4.6.5.4.  <roles>  . . . . . . . . . . . . . . . . . . . . . 28



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         4.6.5.5.  <languages>  . . . . . . . . . . . . . . . . . . . 28
         4.6.5.6.  <cascaded-focus> . . . . . . . . . . . . . . . . . 28
         4.6.5.7.  <allow-refer-users-dynamically>  . . . . . . . . . 28
         4.6.5.8.  <allow-invite-users-dynamically> . . . . . . . . . 28
         4.6.5.9.  <allow-remove-users-dynamically> . . . . . . . . . 29
         4.6.5.10. <endpoint> . . . . . . . . . . . . . . . . . . . . 29
     4.7.  <sidebars-by-ref>  . . . . . . . . . . . . . . . . . . . . 30
     4.8.  <sidebars-by-val>  . . . . . . . . . . . . . . . . . . . . 30
   5.  RELAX NG Schema  . . . . . . . . . . . . . . . . . . . . . . . 30
   6.  XML Schema Extensibility . . . . . . . . . . . . . . . . . . . 41
   7.  XML Example  . . . . . . . . . . . . . . . . . . . . . . . . . 41
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 51
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 52
     9.1.  Relax NG Schema Registration . . . . . . . . . . . . . . . 52
     9.2.  XML Namespace Registration . . . . . . . . . . . . . . . . 53
     9.3.  Conference Object Identifier Registration  . . . . . . . . 53
     9.4.  Conference User Identifier Registration  . . . . . . . . . 54
   10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 54
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 55
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 55
     11.2. Informative References . . . . . . . . . . . . . . . . . . 55
   Appendix A.  Non-Normative RELAX NG Schema in XML Syntax . . . . . 56
   Appendix B.  Non-Normative W3C XML Schema  . . . . . . . . . . . . 84
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 93



























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1.  Introduction

   There is a core data set of conference information that is utilized
   in any conference, independent of the specific conference media.
   This core data set called the 'conference information data model' is
   defined in this document using an Extensible Markup Language (XML)-
   based.  The conference information data model defined in this
   document is logically represented by the conference object.

   Conference objects are a fundamental concept in Centralized
   Conferencing, as described in the Centralized Conferencing Framework
   [RFC5239].  A conference object contains data that represents a
   conference during each of its various stages (e.g., created/creation,
   reserved/reservation, active/activation, completed/completion).  A
   conference object can be manipulated using a conference control
   protocol at a conference server.  The conference object represents a
   particular instantiation of a conference information data model.
   Consequently, conference objects follow the XML format defined in
   this document.

   A conference object contains the core information of a conference
   (i.e., capabilities, membership, call control signaling, media, etc.)
   and specifies by whom, and in which way that information can be
   manipulated.

   Figure 1 shows the logical functional elements of a conference server
   as defined by the Centralized Conferencing Framework [RFC5239].  They
   are a Conference Control Server, a Floor Control Server, a number of
   Foci, and a Notification Service.  A conference control protocol
   provides the interface between a conference control client and the
   conference control server.  A floor control protocol (e.g., BFCP
   [RFC4582]) provides the interface between a floor control client and
   the floor control server.  A call signaling protocol (e.g., SIP,
   H.323, Q.931, ISUP, etc.) provides the interface between a call
   signaling client and a Focus.  A notification protocol (e.g., SIP-
   based event notifications [RFC3265]) provides the interface between
   the conferencing client and the Notification Service.  Within a
   conference, the conference control server, floor control server, and
   focus can modify the information in the conference object.












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      ...............................................................
      . Conferencing Server                                         .
      .       +---------------------------------------------------+ .
      .       |       C o n f e r e n c e   o b j e c t           | .
      .     +-+--------------------------------------------------+| .
      .     |       C o n f e r e n c e   o b j e c t            || .
      .   +-+---------------------------------------------------+|| .
      .   |       C o n f e r e n c e   o b j e c t             ||| .
      .   | +--------------------------------------------------+||| .
      .   | | Conference Information Data Model                |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Conference description  (times, duration)    | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Host information                             | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Conference state                             | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Floor information                            | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Membership (users, capacity)                 | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Sidebars, Etc.                               | |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | +----------------------------------------------+ |||| .
      .   | | | Etc.                                         | |||| .
      .   | | +----------------------------------------------+ |||+ .
      .   | +--------------------------------------------------+|+  .
      .   +----^------------------^-------------^--------|------+   .
      .        |                  |             |        |          .
      . +------v-------+ +--------v-----+ +-----v-+ +----v-------+  .
      . | Conference   | | Floor        | |       | |            |  .
      . | Control      | | Control      | |Foci   | |Notification|  .
      . | Server       | | Server       | |       | |Service     |  .
      . +-----^--------+ +---^----------+ +-^-----+ +------------+  .
      ........|..............|..............|..........|.............
              |Conference    |Floor         |Call      |Notification
              |Control       |Control       |Signaling |Protocol
              |Protocol      |Protocol      |Protocol  |
      ........v..............v..............v..........v.............
      .     C  o  n  f  e  r  e  n  c  i  n  g     C  l i  e  n  t  .
      ...............................................................

                 Figure 1: Conference Server Architecture



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   The Session Initiation Protocol (SIP) Event Package for Conference
   State, specified in [RFC4575], already defines a data format for
   conferences.  However, that model is SIP specific and lacks elements
   related to some of the functionality defined by the Centralized
   Conferencing Framework [RFC5239] (e.g., floor control).  The data
   model defined in this document constitutes a superset of the data
   format defined in [RFC4575].  The result is a data format that
   supports more call signaling protocols besides SIP and that covers
   all the functionality defined in the Centralized Conferencing
   Framework [RFC5239].


2.  Terminology

   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 [RFC2119].

   This document uses the terminology defined in the Centralized
   Conferencing Framework [RFC5239], the SIPPING conferencing framework
   [RFC4353] and the BFCP (Binary Floor Control Protocol) specification
   [RFC4582].  Readers of this document should be familiar with the
   terminology used in those documents.


3.  Overview

   The data model specified in this document is the result of extending
   the data format defined in [RFC4575] with new elements.  Examples of
   such extensions include scheduling elements, media control elements,
   floor control elements, non-SIP URIs, and addition of localization
   extensions to text elements.  This data model can be used by
   conference servers providing different types of basic conferences.
   It is expected that this data model can be further extended with new
   elements in the future in order to implement additional advanced
   features.

3.1.  Data Model Format

   A conference object document is an XML [W3C.REC-xml-20001006]
   document that MUST be well formed and SHOULD be valid.  Conference
   object documents MUST be based on XML 1.0 and SHOULD be encoded using
   UTF-8.

3.2.  Data Model Namespace

   This specification defines a new namespace specification for
   identifying the elements defined in the data model.  This namespace



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   is as follows:

   urn:ietf:params:xml:ns:xcon-conference-info

3.3.  The Conference Object Identifier

   The conference object identifier (XCON-URI) can be viewed as a key to
   accessing a specific conference object.  It can be used, for
   instance, by the conference control protocol to access, manipulate
   and delete a conference object.  A conference object identifier is
   provided to the conferencing client by the conference notification
   service or through out-of-band mechanisms (e.g.  E-Mail).

   A conferencing system may maintain a relationship between the
   conference object identifiers and the identifiers associated with
   each of the complementary centralized conferencing protocols (e.g.,
   call signaling protocols, BFCP, etc.).  To facilitate the maintenance
   of these relationships, the conference object identifier acts as a
   top level identifier within the conferencing system for the purpose
   of identifying the interfaces for these other protocols.  This
   implicit binding provides a structured mapping of the various
   protocols with the associated conference object Identifier.  Figure 2
   illustrates the relationship between the identifiers used for the
   protocols and the general conference object identifier (XCON-URI).



























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                            +--------------------------+
                            |       Conference         |
                            |         Object           |
                            |       Identifier         |
                            +--------------------------+
                            |  xcon:Ji092i@example.com |
                            +------+-------------------+
                                        |
                                        |
                                        |
                      +-----------------+---------------+
                      |                                 |
          +-----------+-----------+          +----------+---------+
          |   CSP Conference IDs  |          |BFCP 'Conference ID'|
          +-----------------------+          +--------------------+
          | h323:i092@example.com |          |        i092        |
          | tel:+44(0)2920930033  |          +----------+---------+
          | sip:i092@example.com  |                     |
          +-----------------------+             +-------+--------+
                                                | BFCP 'Floor ID'|
                                                +----------------+
                                                |      543       |
                                                |      236       |
                                                +----------------+

                    Figure 2: Conference Object Mapping

   In Figure 2, the conference object identifier acts as the top level
   key in the identification process.  The call signaling protocols have
   an associated conference user identifier, often represented in the
   form of URIs.  The binary floor control protocol, as defined in
   [RFC4582], defines the 'conference ID' identifier which represents a
   conference instance within floor control.  When created within the
   conferencing system, the 'conference ID' has a 1:1 mapping to the
   unique conference object Identifier(XCON-URI).  Operations associated
   with the conference control protocols are directly associated with
   the conference object, thus the primary identifier associated with
   these protocols is the conference object identifier(XCON-URI).  The
   mappings between additional protocols/interface is not strictly 1:1
   and does allow for multiple occurrences.  For example, multiple call
   signaling protocols will each have a representation that is
   implicitly linked to the top level conference object identifier e.g.
   H323 and SIP URIs that represent a conference instance.  It should be
   noted that a conferencing system is free to structure such
   relationships as required and this information is just included as a
   guideline that can be used.

   Further elements can be added to the tree representation in Figure 2



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   to enable a complete representation of a conference instance within a
   conferencing system.

3.3.1.  Conference Object URI Definition


   XCON-URI = "xcon" ":" [conf-object-id "@"] host [ ":" port ]

    conf-object-id = 1*( unreserved / "+" / "=" / "/" )


   host, port, and unreserved are defined in RFC3986[RFC3986]

3.3.2.  Normalization and Conference Object URI Comparison

   In order to facilitate the comparison of the XCON-URI identifiers,
   all the components of the identifiers MUST be converted to lowercase.
   After normalizing the URI strings, the URIs comparison MUST applied a
   character-by-character basis as prescribed by RFC3986, Section 6.2.1.

3.4.  Data Model Structure

   The information in this data model is structured in the following
   manner.  All the information related to a conference is contained in
   a <conference-info> element.  The <conference-info> element contains
   the following child elements:

   o  The <conference-description> element describes the conference as a
      whole.  It has, for instance, information about the URI of the
      conference, maximum users allowed in the conference, media
      available in the conference, or the time the conference will
      start.
   o  The <host-info> element contains information about the entity
      hosting the conference (e.g., its URI).
   o  The <conference-state> element informs the subscribers about the
      changes in the overall conference information.
   o  The <floor-information> element contains information about the
      status of the different floors in the conference.
   o  The <users> element describes the membership information as a
      whole.  The <users> element contains a set of <user> child
      elements, each describing a single participant in the conference.
   o  If a participant in the main conference joins a sidebar, a new
      element is created in the conference referenced from the
      <sidebars-by-ref> element or under one of the <sidebars-by-val>
      elements.

   Note that some of the elements described above such <conference-
   info>, <conference-description>, <sidebars-by-ref>, or <sidebars-by-



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   val> are not defined in the data model but are defined in the data
   format of [RFC4575].  We describe them here because they are part of
   the basic structure of the data model.


4.  Data Model Definition

   The following non-normative diagram shows the structure of conference
   object documents.  The operator "!" preceding an element indicates
   that the element is mandatory in the data model.  The operator "*"
   following an element indicates that the element is introduced and
   defined in this document.  That is, elements without a "*" have
   already been defined in [RFC4575].

   !<conference-info>
        |
        |--!<conference-description>
        |     |--<language>*
        |     |--<display-text>
        |     |--<subject>
        |     |--<free-text>
        |     |--<keywords>
        |     |--<allow-sidebars>*
        |     |--<cloning-parent>*
        |     |--<sidebar-parent>*
        |     |--<conference-time>*
        |     |      |--<entry>*
        |     |      |    |--<base>*
        |     |      |    |--<mixing-start-offset>*
        |     |      |    |--<mixing-end-offset>*
        |     |      |    |--<can-join-after-offset>*
        |     |      |    |--<must-join-before-offset>*
        |     |      |    |--<request-user>*
        |     |      |    |--<notify-end-of-conference>*
        |     |      |    |--<allowed-extend-mixing-end-offset>*
        |     |           ...
        |     |--<conf-uris>
        |     |      |--<entry>
        |     |      |    |--<uri>
        |     |      |    |--<display-text>
        |     |      |    |--<purpose>
        |     |      |    |--<conference-password>*
        |     |      ...
        |     |--<service-uris>
        |     |      |--<entry>
        |     |      |    |--<uri>
        |     |      |    |--<display-text>
        |     |      |    |--<purpose>



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        |     |      ...
        |     |--<maximum-user-count>
        |     |      ...
        |     |--<available-media>
        |     |      |--!<entry>
        |     |      |     |--<display-text>
        |     |      |     |--<type>
        |     |      |     |--<status>
        |     |      |     |--<mixing-mode>*
        |     |      |     |--<codecs>*
        |     |      |     |    |--<codec>*
        |     |      |     |    |    |--<subtype>*
        |     |      |     |    |--<codec>*
        |     |      |     |    |    |--<subtype>*
        |     |      |     |    ...
        |     |      |     |--<controls>*
        |     |      |     |    |--<mute>*
        |     |      |     |    |--<gain>*
        |     |      |     |   ...
        |     |      |--<entry>
        |     |      |     |--<display-text>
        |     |      |     |--<type>
        |     |      |     |--<status>
        |     |      |     |--<mixing-mode>*
        |     |      |     |--<codecs>*
        |     |      |     |    |--<codec>*
        |     |      |     |    |    |--<subtype>*
        |     |      |     |    |--<codec>*
        |     |      |     |    |    |--<subtype>*
        |     |      |     |    ...
        |     |      |     |--<controls>*
        |     |      |     |    |--<pause-video>*
        |     |      |     |    |--<video-layout>*
        |     |      |     |   ...
        |     |      ...
        |
        |--<host-info>
        |     |--<display-text>
        |     |--<web-page>
        |     |--<uris>
        |     |     |--<entry>
        |     |     |    |--<uri>
        |     |     |    |--<display-text>
        |           ...
        |--<conference-state>
        |     |--<allow-conference-event-subscription>*
        |     |--<user-count>
        |     |--<active>



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        |     |--<locked>
        |
        |--<floor-information>*
        |     |--<conference-ID>*
        |     |--<allow-floor-events>*
        |     |--<floor-request-handling>*
        |     |--<conference-floor-policy>*
        |     |     |--<floor>*
        |     |     |    |--!<media-label>*
        |     |     |    |--!<algorithm>*
        |     |     |    |--<max-floor-users>*
        |     |     |    |--<moderator-id>*
        |     |     |   ...
        |     |     ...
        |
        |--!<users>
        |     |--<join-handling>*
        |     |--<user-admission-policy>*
        |     |--<allowed-users-list>*
        |     |     |--<target>*
        |     |     |
        |     |     |--<persistent-list>*
        |     |     |     |--<user>*
        |     |     |     |     |-- <email>*
        |     |
        |     |--<deny-users-list>*
        |     |
        |     |--<user>
        |     |    |--<display-text>
        |     |    |--<associated-aors>
        |     |    |--<provide-anonymity>*
        |     |    |--<roles>
        |     |    |    |
        |     |    |   ...
        |     |    |--<languages>
        |     |    |--<cascaded-focus>
        |     |    |--<allow-refer-users-dynamically>*
        |     |    |--<allow-invite-users-dynamically>*
        |     |    |--<allow-remove-users-dynamically>*
        |     |    |--!<endpoint>
        |     |    |      |--<display-text>
        |     |    |      |--<referred>
        |     |    |      |--<status>
        |     |    |      |--<joining-method>
        |     |    |      |--<joining-info>
        |     |    |      |--<disconnection-method>
        |     |    |      |--<disconnection-info>
        |     |    |      |--<media>



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        |     |    |      |    |--<type>
        |     |    |      |    |--<display-text>
        |     |    |      |    |--<label>
        |     |    |      |    |--<src-id>
        |     |    |      |    |--<status>
        |     |    |      |    |--<to-mixer>*
        |     |    |      |    |      |--<floor>*
        |     |    |      |    |      |--<controls>*
        |     |    |      |    |      |      |--<mute>*
        |     |    |      |    |      |      |--<gain>*
        |     |    |      |    |      |     ...
        |     |    |      |    |--<from-mixer>*
        |     |    |      |    |      |--<floor>*
        |     |    |      |    |      |--<controls>*
        |     |    |      |    |      |      |--<pause-video>*
        |     |    |      |    |      |     ...
        |     |    |      |   ...
        |     |    |      |--<call-info>
        |     |    |      |    |--<sip>
        |     |    |      |    |   |--<display-text>
        |     |    |      |    |   |--<call-id>
        |     |    |      |    |   |--<from-tag>
        |     |    |      |    |   |--<to-tag>
        |          ...    ...
        |--<sidebars-by-ref>
        |     |--<entry>
        |     |     |-- <user>
        |     |     |-- <display-text>
        |     |--<entry>
        |     |     |-- <user>
        |     |     |-- <display-text>
        |     ...
        |--<sidebars-by-val>
        |     |--<entry>
        |     |     |
        |     |    ...
        |     |--<entry>
        |     |     |
        |     ...   ...


                      Figure 3: Non-normative diagram

   The following sections describe these elements in detail.  The full
   Relax NG schema is provided Section 5.






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4.1.  <conference-info>

   A conference object document begins with the root element tag
   <conference-info>, which is defined in [RFC4575].  The <conference-
   info> attributes are described in [RFC4575].  Note that the
   <conference-info> element does not have the attributes 'state' and
   'version' defined in [RFC4575] for this element because these
   attributes only apply to notification mechanisms.

   In addition, [RFC4575] defines an 'entity' attribute that contains
   the conference object identifier (XCON-URI) that identifies the
   conference being described in the document.

   The <conference-info> element contains the <conference-description>,
   <host-info>, <conference-state>, <floor-information>, <users>,
   <sidebars-by-ref>, and <sidebars-by-val> child elements.  All these
   elements, except <floor-information>, are defined in [RFC4575].  A
   conference document MUST at least include the <conference-
   description> and <users> child elements.

4.2.  <conference-description>

   The <conference-description> element, which is defined in [RFC4575],
   describes the conference as a whole.  It SHOULD have an extra
   attribute 'lang' to specify the language used in the contents of this
   element.  It is comprised of <language>, <display-text>, <subject>,
   <free-text>, <keywords>, <allow-sidebars>, <cloning-parent>,
   <sidebar-parent>, <conference-time>, <conf-uris>, <service-uris>,
   <maximum-user-count>, and <available-media>.

   The following sections describe these elements in more detail.  Other
   child elements MAY be defined in the future to extend the
   <conference-description> element.

4.2.1.  <language>

   The <language> element indicates the predominant language that is
   expected to be employed within a conference.  The possible values of
   this element are the values of the 'Subtag' column of the [RFC5646]
   defined in IANA [IANA-Lan].  This element is not enforcing the
   language of the conference, but only informs the participants about
   the desirable language that they should use in the conference.
   Participants are free to switch to other languages if they like.

4.2.2.  <display-text>

   The <display-text> element is described in section 5.3 of [RFC4575].




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4.2.3.  <subject>

   The <subject> element is described in section 5.3 of [RFC4575].

4.2.4.  <free-text>

   The <free-text> element is described in section 5.3 of [RFC4575].

4.2.5.  <keywords>

   The <keywords> element is described in section 5.3 of [RFC4575].

4.2.6.  <allow-sidebars>

   The <allow-sidebars> element represents a boolean value.  If set to
   TRUE, the conference is allowed to create sidebar conferences.  If
   absent, or set to FALSE, the conference can not create sidebar
   conferences.

4.2.7.  <cloning-parent>

   When the <cloning-parent> is present, it indicates that the
   conference object is a child of a parent conference.  The <cloning-
   parent> element contains the conference object Identifier (XCON-URI)
   (different from the main XCON-URI) of the parent.

4.2.8.  <sidebar-parent>

   When the <sidebar-parent> is present, it indicates that the
   conference object represents a sidebar of another conference.  The
   <sidebar-parent> element contains the conference object Identifier
   (XCON-URI) (different from the main XCON-URI) of the parent.

4.2.9.  <conference-time>

   The <conference-time> element contains the information related to
   conference time, policy, and duration of a conference.  The
   <conference-time> element contains one or more <entry> elements each
   defining the time and policy information specifying a single
   conference occurrence.  The <conference-time> element differs from
   the iCalendar objects [RFC5545] in the possibility to define
   different policies (<can-join-after-offset>, <must-join-before-
   offset>) for the same conference at different times.

   Every <entry> element contains the following child elements:






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   o  <base>: The <base> child element specifies the iCalendar object of
      the conference.  The iCalendar object components are defined in
      [RFC5545].
   o  <mixing-start-offset>: The <mixing-start-offset> child element
      specifies when the conference media mixing starts before the
      conference starts.  If the <mixing-start-offset> element is not
      present, it indicates that the conference media mixing starts
      immediately.  The <mixing-start-offset> has the mandatory
      'required-participant' attribute.  This attribute contains one of
      the following values: "none", "administrator", "moderator",
      "user", "observer", and "participant".  The roles semantic
      definition is out of the scope of this document and is subject to
      future policy documents.  More values can be specified in the
      future.  The 'required-participant' attribute allows a privileged
      user to define when media mixing starts based on the latter of the
      mixing start time, and the time the first participant arrives.  If
      the value is set to "none'", mixing starts according to the mixing
      start time.
   o  <mixing-end-offset>: The <mixing-end-offset> child element
      specifies the time a conference media mixing stops after the
      conference stops.  If the <mixing-end-offset> element is not
      present, it indicates that the conference occurrence is not
      bounded.  The <mixing-end-offset> element has the mandatory
      'required-participant' attribute.  This attribute contains one of
      the following values: "none", "administrator", "moderator",
      "observer", "user", and "participant".  More values can be
      specified in the future.  The 'required-participant' attribute
      allows a privileged user to define when media mixing ends based on
      the earlier of the <mixing-end-offset>, and the time the last
      participant leaves.  If the value is set to "none", mixing stops
      according to the <mixing-end-offset>.  If the conference policy
      was modified so that last privileged user is now a normal
      conference participant, and the conference requires a privileged
      user to continue; that conference MUST terminate.
   o  <can-join-after-offset>: An administrator can indicate the time
      when users can join a conference by populating the <can-join-
      after-offset> element.
   o  <must-join-before-offset>: An administrator can define the time
      after which new users are not allowed to join the conference
      anymore.
   o  <request-user>: It defines the time when users or resources on the
      <allowed-users-list> are requested to join the conference by using
      the <request-users> element.
   o  <notify-end-of-conference>: The <notify-end-of-conference> element
      defines in seconds when the system MUST send a notification when
      the end of the conference is approaching.  If the <notify-end-of-
      conference> element is not present, it indicates that the system
      does not notify the users when the end of the conference is



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      approaching.
   o  <allowed-extend-mixing-end-offset>: The <allowed-extend-mixing-
      end-offset> refers to the possibility to extend the conference.
      It has a boolean value.

4.2.10.  <conf-uris>

   The <conf-uris> element contains the identifiers to be used in order
   to access the conference by different signaling means.  This document
   describes a new element, <conference-password>.  This element
   contains the password(s) of the conference, for instance, PSTN
   conference will store the 'PIN code' in this element.  All the other
   <conf-uris> child element are described in section 5.3.1 of
   [RFC4575].

4.2.11.  <service-uris>

   The <service-uris> describes auxiliary services available for the
   conference.  The <service-uris> element is described in section 5.3.2
   of [RFC4575].

4.2.12.  <maximum-user-count>

   The <maximum-user-count> contains the overall number of users allowed
   to join the conference.  Note that this value is set by an
   administrator and can reflect any local policies such as network
   consumption, CPU processing power, and licensing rules.

4.2.13.  <available-media>

   The <available-media> element consists of a sequence of <entry> child
   elements.  Each <entry> element contain the 'label' attribute that is
   the media stream identifier assigned by the conferencing server.  The
   attribute 'label' is described in [RFC4575], section 5.3.4.  Each
   <entry> element contains the following child elements:

   o  The <type> element is described in section 5.3.4 of [RFC4575].
   o  The <display-text> element is described in section 5.3.4 of
      [RFC4575].
   o  The <status> element is described in section 5.3.4 of [RFC4575].
   o  The child element <mixing-mode> describes a default scheduling
      policy by which the mixer will build the outgoing stream from the
      incoming streams.  Note that this policy is different than the
      policy describing the floors for each media.  The <mixing-mode>
      child element MUST contain one and only one of the "Moderator-
      controlled", "FCFS", and "Automatic" values indicating the default
      algorithm to use with every media stream.  The "Moderator-
      controlled" value indicates that the moderator of the conference,



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      controls the media stream policy.  The "FCFS" value indicates a
      'first-come-first-served' policy.  The "Automatic" value means the
      mixer choose the best scheduling policy for the conference.
   o  The <codecs> element specifies the allowed codecs in the
      conference.  It has an attribute 'decision' that specifies if the
      focus decides the common codec automatically or needs the approval
      of the moderator of the conference ("automatic", "moderator-
      controlled").  The <codecs> element contains <codec> elements.  A
      <codec> element can have the attribute 'name' and 'policy'.  The
      'name' attribute is a codec identifier assigned by the
      conferencing server.  The 'policy' attribute contains the policy
      for that codec (allowed, or disallowed).  The <codec> element has
      the child element <subtype> which stores the codec's name.  The
      possible values of this element are the values of the 'subtype'
      column of the RTP Payload Format media types per [RFC4855] defined
      in IANA [IANA].  It is expected that future conferencing
      specifications will define corresponding schema extensions, as
      appropriate.
   o  The <controls> element contains the basic audio and video global
      control elements for a conference.  It is expected that for the
      majority of the basic conferences, these controls are sufficient.
      If the conference server wants to support more advanced controls,
      then it is recommended that an extension to the data model be
      used.  In the <controls> element the schema is extensible, hence
      new control types can be added in the future.  So moderator
      controls that affect all media output would go under the
      <available-media> element.  The following controls elements are
      defined for <controls>:
      *  The <mute> element is used in conjunction with an audio stream
         to cease transmission of any audio from the associated stream.
         That means that for the entire duration where mute is
         applicable, all current and future participants of the
         conference are muted and will not receive any audio.  It has a
         "boolean" value.  If this control is not specified, access to
         the control is not available to the client.
      *  The <pause-video> element is used in conjunction with a video
         stream to cease transmission of associated media.  It has a
         "boolean" value.  If this control is not specified, the access
         to the control is not available to the client.
      *  The <gain> element is used in conjunction with a media output
         stream to indicate the amount of amplification of an audio
         stream.  The value is an integer number that ranges from -127
         to 127.  If this control is not specified, access to the
         control is not available to the client.
      *  The <video-layout> element is used in conjunction with a video
         stream to specify how the video streams (of participants) are
         viewed by each participant.  Only one layout type can be
         specified for each output stream.  If there are fewer



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         participants than panels in the specified layout, then blanking
         (black screen) MAY be mixed into the stream on the behalf of
         the missing input streams.  If unspecified, the <video-layout>
         default type SHOULD be "single-view".  The <video-layout> types
         are as follows, although any number of custom layouts may be
         specified in future extensions:
         +  single-view: Only one stream is presented by the focus to
            all participants in one panel.
         +  dual-view: This dual view option will present the video
            side-by-side in 2 panels and not alter the aspect ratio of
            the streams.  This will require the focus to introduce
            blanking on parts of the overall image as viewed by the
            participants.
         +  dual-view-crop: This side-by-side layout option instructs
            the focus to alter the aspect ratio of the streams (alter-
            aspect-ratio=TRUE) so that blanking is not necessary.  The
            focus handles the cropping of the streams.
         +  dual-view-2x1: This layout option instructs the focus to
            place one stream above the other, in essence with two rows
            and one column.  In this option the aspect ratio is not
            altered and blanking is introduced.
         +  dual-view-2x1-crop: This layout option also instructs the
            focus to place one stream above the other, in essence with
            two rows and one column.  In this option the aspect ratio is
            altered and the video streams are cropped.
         +  quad-view: Four equal-sized panels in a 2x2 layout is
            presented by the focus to all participants.  Typically the
            aspect ratio of the streams are maintained (alter-aspect-
            ratio= FALSE).
         +  multiple-3x3: Nine equal-sized panels in a 3x3 layout is
            presented by the focus to all participants.  Typically the
            aspect ratio of the streams are preserved.
         +  multiple-4x4: Sixteen equal-sized panels in a 4x4 layout is
            presented by the focus to all participants.  Typically the
            aspect ratio of the streams are preserved.
         +  multiple-5x1: This option refers to a 5x1 layout where one
            panel will occupy 4/9 of the mixed video stream while the
            others will each occupy 1/9 of the stream.  Typically the
            aspect ratio of the streams is preserved.
         +  automatic: This option allows the focus to add panels as
            streams are added.

4.3.  <host-info>

   The <host-info> element contains information about the entity hosting
   the conference.  This information is usually set before conference
   activation, and is rarely changed during the conference lifetime.
   The <host-info> element and its child elements are described in



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   [RFC4575], section 5.4.  Future extensions to the <host-info> element
   may define new values.

4.4.  <conference-state>

   The <conference-state> is introduced in [RFC4575].  The <conference-
   state> element contains the <allow-conference-event-subscription>,
   <user-count>, <active>, and <locked> child elements.

4.4.1.  <allow-conference-event-subscription>

   The <allow-conference-event-subscription> element represents a
   boolean action.  If set to TRUE, the focus is instructed to allow the
   subscription to conference state events, such as 'SIP Event Package
   for Conference State' [RFC4575].  If set to FALSE, the subscription
   to conference state events MUST be rejected.  If this element is
   undefined it has a default value of TRUE, causing the subscription to
   conference state events to be accepted.

4.4.2.  <user-count>

   The <user-count> child element is explained in [RFC4575], section
   5.5.1.

4.4.3.  <active>

   The <active> child element is explained in [RFC4575], section 5.5.2.

4.4.4.  <locked>

   The <locked> child element is explained in [RFC4575], section 5.5.3.

4.5.  <floor-information>

   The <floor-information> element contains the <conference-ID>, <allow-
   floor-events>, <floor-request-handling>, and <conference-floor-
   policy> child elements.  Other elements from different namespaces MAY
   be present for the purposes of extensibility.  The absence of this
   element from an XML document indicates that the conference does not
   have a floor.

4.5.1.  <conference-ID>

   The <conference-ID> represents a conference instance within floor
   control.  When created within the conferencing system, the
   'conference-ID' can be represented by the unique conference object
   Identifier (XCON-URI).  When BFCP serves as the floor control
   protocol, the <conference-ID> is a 32-bit BFCP conference identifier



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   defined in [RFC4582] section 5.1 and there is a 1:1 mapping to the
   XCON-URI.

4.5.2.  <allow-floor-events>

   The <allow-floor-events> element represents a boolean action.  If set
   to TRUE, the focus is instructed to accept the subscription to floor
   control events.  If set to FALSE, the focus is instructed to reject
   the subscription.  If this element is undefined, it has a default
   value of FALSE, causing the subscription to floor control events to
   be rejected.

   A conference participant can subscribe himself to a floor control
   event in two different ways: one method is using an offer/answer
   exchange mechanism ([RFC3264]) using SIP INVITE and BFCP parameters
   in the SDP ([RFC4583]), the other method is a general authorization
   mechanism described in section 9 of [RFC4582] and in [RFC5018].
   Future documentation may define additional connection mechanisms.

4.5.3.  <floor-request-handling>

   The <floor-request-handling> element defines the actions used by the
   conference focus to control floor requests.  This element defines the
   action that the focus is to take when processing a particular request
   to a floor within a conference.  This element defines values of:

   o  "block": This action instructs the focus to deny the floor
      request.  This action is the default action taken in the absence
      of any other actions.
   o  "confirm": This action instructs the focus to allow the request.
      The focus then uses the defined floor algorithm to further allow
      or deny the floor.  The algorithms used are outside the scope of
      this document.

   Note that this section discusses floor control information,
   therefore, the value "block" in a <floor-request-handling> element is
   not related with the "block" value in the <join-handling> element
   (see Section 4.6).

4.5.4.  <conference-floor-policy>

   The <conference-floor-policy> element has one or more <floor> child
   elements.  Every <floor> child elements has an attribute 'id' which
   uniquely identifies a floor within a conference.  In the case of BFCP
   [RFC4582], the 'id' attribute corresponds to the floor-id identifier
   defined in [RFC4582] section 5.2.2.





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   o  <media-label>: Every floor is identified for one or more mandatory
      <media-label> element.  If the <available-media> information is
      included in the conference document, the value of this element
      MUST be equal to the 'label' value of the corresponding media
      stream <entry> in the <available-media> container.  The number of
      those elements indicates how many floors the conference can have.
      A floor can be used for one or more media types;
   o  <algorithm>: A floor can be controlled using many algorithms; the
      mandatory <algorithm> element MUST be set to any of the
      "moderator-controlled", "FCFS" or "random" values indicating the
      algorithm.  The "Moderator-controlled" value indicates that the
      moderator of the conference controls the floor.  The "FCFS" value
      states for 'first-come-first-served' floor control.
   o  <max-floor-users>: The <max-floor-users> child element in the
      <floor> element is optional and, if present, dictates the maximum
      number of users who can have the floor at one time.
   o  <moderator-id>: The optional <moderator-id> indicates the 'User
      ID' of the moderator(s).  It MUST be set if the element
      <algorithm> is set to "Moderator-controlled" value.  When the
      floor is created within the conferencing system, the XCON-User
      identifier MAY be used as the moderator-id.  In the case of BFCP
      as the floor control protocol, the <moderator-id> is defined in
      [RFC4582] section 3.  Note that [RFC4582] refers to the moderator
      role as a 'floor chair'.

4.6.  <users>

   The <users> element is described in [RFC4575] and contains the <join-
   handling>, <user-admission-policy>, <allowed-users-list> and <deny-
   users-list> defined in this document and <user> child elements
   defined in [RFC4575].  Note that the <users> element does not have
   the attribute 'state' defined in [RFC4575] for this element because
   this attribute only applies to notifications mechanism.  The
   following sections describe these elements in more detail.  Other
   child elements and attributes can be used to extend <users> in the
   future.

4.6.1.  <join-handling>

   The <join-handling> element defines the actions used by the
   conference focus to control conference participation.  This element
   defines the action that the focus is to take when processing a
   particular request to join a conference.  This element defines values
   of:
   o  "block": This action instructs the focus to deny access to the
      conference.  This action is the default action taken in the
      absence of any other actions.




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   o  "confirm": This action instructs the focus to place the
      participant on a pending list (e.g., by parking the call on a
      music-on-hold server), awaiting moderator input for further
      actions.
   o  "allow": This action instructs the focus to accept the conference
      join request and grant access to the conference within the
      instructions specified in the transformations of this rule.
   o  "authenticate": This action instructs the focus that the user has
      to provide a combination of username/password.
   o  "directed-operator": This action instructs the focus to direct the
      user to an operator.

4.6.2.  <user-admission-policy>

   The <user-admission-policy> is an element that lets an organizer (or
   a participant with appropriate rights) choose a policy for the
   conference that controls how users are authenticated into the
   conference, using a mechanism of the conference's choosing.  Since a
   variety of signaling protocols are possible, a variety of
   authentication mechanism - determined by every individual conference
   servers - may need to be mapped from the different protocols.  The
   specific types of authentication mechanism are beyond the scope of
   this document.  The list of possible values are:

   o  "closedAuthenticated": A 'closedAuthenticated' policy requires
      each conference participant to be in the allowed users list
      (listed under the <allowed-users-list> XML element) with each
      participant being sufficiently (up to local policy) authenticated.
      Conference join requests for users not in the allowed users list
      or participants not authenticated should be rejected unless a
      <join-handling> action of 'confirm' is selected in which case the
      user is placed on a pending list as indicated earlier.
   o  "openAuthenticated": An 'openAuthenticated' policy requires each
      conferencing participant to be sufficiently authenticated (as
      before) but does not restrict which participants can join the
      conference.  Typically this implies that anyone capable of
      authenticating with the conferencing system may join the
      conference.
   o  "anonymous": An 'anonymous' policy allows any join requests in and
      is the least restrictive policy.

4.6.3.  <allowed-users-list>

   The <allowed-users-list> child element contains a list of user URIs
   (e.g.  SIP URI, xcon-userid defined in Section 4.6.5), roles (defined
   in Section 4.6.5.4), or domains (e.g.: *@example.com) that the focus
   uses to determine who can join the conference, who can be invited to
   join a conference, or who the focus needs to "refer to" the



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   conference.  The <allowed-users-list> element includes zero or more
   <target> child elements.  This child element includes the mandatory
   'uri' attribute and the mandatory 'method' attribute.  The same 'uri'
   attribute with different method values can appear in the list more
   than once.

   The 'method' attribute is a list with the following values:

   o  "dial-in": The value "dial-in" is used by the focus to determine
      who can join the conference.
   o  "dial-out": The value "dial-out" contains a list of resources that
      the focus will initiate a session with.
   o  "refer": The value "refer" is used by the focus to determine the
      resources that the focus needs to "refer to" the conference.  In
      SIP, this is achieved by the focus sending a REFER request to
      those potential participants.  In a different paradigm, this could
      also mean that the focus sends an SMS or an email to the referred
      user.  This list can be updated during the conference lifetime so
      it can be used for mid-conference refers as well.

   The "refer" value differs from the "dial-out" in that the resources
   on the "refer" value are expected to initiate the session
   establishment toward the focus themselves.  It is also envisioned
   that different users will have different access rights to those lists
   and therefore a separation between the two is needed.

   The <allowed-users-list> element has a <persistent-list> child
   element as well.  Some chatroom systems allow -- and some require --
   registration of detailed information about a user before they are
   allowed to join a chatroom.  The <persistent-list> child element
   stores persistent information about users who are not actively part
   of an ongoing chatroom session.  The <persistent-list> element stores
   the following information:

   o  user: The <user> element stores the name, nickname, the conference
      user identifier (XCON-USERID) and email address of a user.  It has
      three attributes: 'name', 'nickname' and 'id' and an <email>
      element.  Future extensions to this schema may define new elements
      for the <user> element.

   Future extensions to this schema may define new elements for the
   <target> element.

4.6.4.  <deny-users-list>

   The <deny-users-list> child element contains a list of user URIs
   (e.g.  SIP URI, xcon-userid defined in Section 4.6.5), roles (defined
   in Section 4.6.5.4), or domains (e.g.: *@example.com) that the focus



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   uses to determine who has been 'banned' from the conference.  Such
   banned users are prevented from re-joining the chatroom until they
   have been un-banned.

4.6.5.  <user> and Its <user> Sub-elements

   The element <user> is described in [RFC4575] and describes a single
   participant in the conference.  The <user> element has an attribute
   'entity'.  Note that the <user> element does not have the attribute
   'state' defined in [RFC4575] for this element because this attribute
   only applies to notifications mechanism.

   The attribute 'entity' contains a unique conference user identifier
   (XCON-USERID) within the scope of the conference.  The URI format of
   this identifier is as follow:


    XCON-USERID = "xcon-userid" ":" conf-user-id

    conf-user-id = 1*(unreserved)

   [unreserved is defined in RFC3986]

   In order to facilitate the comparison of the XCON-USERID identifiers,
   all the components of the identifiers MUST be converted to lowercase.
   After normalizing the URI strings, the URIs comparison MUST applied a
   character-by-character basis as prescribed by RFC3986, Section 6.2.1.

   Other user identifiers can be associated with this conference user
   identifier and enable the conferencing system to correlate and map
   these multiple authenticated user identities to a single global user
   identifier.  Figure 4 illustrates an example using the conference
   user identifier in association with the user identity defined for
   BFCP, SIP, and H323 user identity.  It should be noted that a
   conferencing system is free to structure such relationships as
   required and this information is just included as a guideline.















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                         +----------------+
                         |   Conference   |
                         |      User      |
                         |   Identifier   |
                         +----------------+
                         |xcon-userid:John|
                         +-------+--------+
                                 |
                                 |
                                 |
          +----------------------+-------------------------+
          |                      |                         |
  +-------+--------+ +-----------+-----------+ +-----------+-----------+
  |  BFCP User ID  | |      SIP User URI     | |     H323 User URI     |
  +----------------+ +-----------------------+ +-----------------------+
  |      543       | |sip:851221@example.com | |h323:taeduk@example.com|
  +----------------+ +-----------------------+ +-----------------------+


                     Figure 4: Conference User Mapping

   The element <user> element contains the <display-text>, <associated-
   aors>, <provide-anonymity>, <roles>, <languages>, <cascaded-focus>,
   <allow-refer-users-dynamically>, <allow-invite-users-dynamically>,
   <allow-remove-users-dynamically>, and <endpoint>.  The following
   sections describe these elements in more detail.

4.6.5.1.  <display-text>

   The <display-text> child element is explained in [RFC4575], section
   5.6.1.

4.6.5.2.  <associated-aors>

   The <associated-aors> child element is explained in [RFC4575],
   section 5.6.2.

4.6.5.3.  <provide-anonymity>

   The <provide-anonymity> element specifies what level of anonymity the
   server should provide to the user.  In this case, the focus provides
   to the rest of the participants an anonymous identity for that user,
   for example anonymousX, or it does not provide any information for
   that user such that other users can not see he is a participant in
   the conference.  This element only affects the way the user
   information is provided to the other participants.  The real
   information about the user is still stored in the data model.  This
   can be achieved by using the <provide-anonymity> element.  This



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   element has three values: 'private', 'semi-private' and 'hidden'.
   The 'private' value specifies that this user is completely anonymous
   in the conference. 'semi-private' value specifies that this user is
   anonymous to all users with equal or lesser permissions in the
   conference. 'hidden' value specifies that other users can not see
   this participant in the conference.

4.6.5.4.  <roles>

   A role provides the context for the set of conference operations that
   a participant can perform.  This element can contain one or more of
   the following values: "administrator", "moderator", "user",
   "participant", "observer", and "none".  The roles semantic definition
   is out of the scope of this document and is subject to future policy
   documents.  This element can be extended with new roles in future
   documents.

4.6.5.5.  <languages>

   The <languages> child element is explained in [RFC4575], section
   5.6.4.

4.6.5.6.  <cascaded-focus>

   The <cascaded-focus> child element is explained in [RFC4575], section
   5.6.5.

4.6.5.7.  <allow-refer-users-dynamically>

   The <allow-refer-users-dynamically> element represents a boolean
   value.  If set to TRUE, a participant is allowed to instruct the
   focus to refer a user to the conference without modifying the
   <allowed-users-list> (in SIP terms, a participant is allowed to send
   a REFER request [RFC3515] to the focus which results in the focus
   sending a REFER request to the user the referrer wishes to join the
   conference).  If set to FALSE, the refer request is rejected.  If
   this element is undefined it has a value of FALSE, causing the refer
   to be rejected.

4.6.5.8.  <allow-invite-users-dynamically>

   The <allow-invite-users-dynamically> element represents a boolean
   action.  If set to TRUE, a participant is allowed to instruct the
   focus to invite a user to the conference without modifying the
   <allowed-users-list> list (in SIP terms, a participant is allowed to
   send a REFER request [RFC3515] to the focus which results in the
   focus sending an INVITE request to the user the referrer wishes to
   join the conference).  If set to FALSE, the refer request is



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   rejected.  If this element is undefined it has a value of FALSE,
   causing the refer to be rejected.

4.6.5.9.  <allow-remove-users-dynamically>

   The <allow-remove-users-dynamically> element represents a boolean
   action.  If set to TRUE, a participant is allowed to instruct the
   focus to remove a user from the conference without modifying the
   ruleset (in SIP terms, a participant is allowed to send a REFER
   request [RFC3515] to the focus which results in the focus sending an
   BYE request to the user the referrer wishes to leave the conference).
   If set to FALSE, the refer request is rejected.  If this element is
   undefined it has a value of FALSE, causing the refer to be rejected.

4.6.5.10.  <endpoint>

   The <endpoint> child element is identical to the element with the
   same name in [RFC4575] except that the 'state' attribute is not
   included.  The 'state' attribute only applies to notification
   mechanisms.  The <endpoint> element can provide the desired level of
   detail about the user's devices and their signaling sessions taking
   part in the conference.

   The <endpoint> element has the following child elements: <display-
   text>, <referred>, <status>, <joining-method>, <joining-info>,
   <disconnection-method>, <disconnection-info>, <media>, <floor>,and
   <call-info>.  All the <endpoint> child elements are defined in
   [RFC4575] with the exception of the <floor> element, <to-mixer>, and
   the <from-mixer> element.

   The <floor> element refers to the floor assigned to a certain
   participant in the conference.  If a participant, for instance, needs
   to talk in the conference, it first needs to get the floor from the
   chair of the conference.  The <floor> element has an attribute 'id'
   which uniquely identifies a floor within a conference.  The 'id'
   attribute corresponds to the floor-id identifier defined in [RFC4582]
   section 5.2.2.  The <floor> element has a "Boolean" value.  A value
   of FALSE indicates that this user does not hold the floor in this
   moment.  If this control is not specified, this user SHOULD NOT
   specify the floor option.

   Besides the <floor> element, the <endpoint>/<media> element has two
   other child elements defined in this document, the <to-mixer>, and
   the <from-mixer>:

   o  <from-mixer>, <to-mixer>: These are controls that apply to a
      user's media stream being sent from the mixer to the participants
      endpoint or to the mixer from the participants endpoint.  The <to-



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      mixer> element details properties associated with the incoming
      streams to the mixer (streams sent to the mixer from the
      participant).  The <from-mixer> element details properties
      associated with the outgoing streams from the mixer (sent from the
      mixer to the participant).  Both of these elements have the
      attribute 'name'.  The 'name' attribute has the values "VideoIn",
      "VideoOut", "AudioOut", and "AudioIn".  The "VideoOut" and
      "AudioOut" media streams detail properties associated with the
      outgoing video and audio from the mixer.  The "VideoIn" and
      "AudioIn" media stream details properties associated with the
      incoming video and audio to the mixer.  More values can be defined
      in the future.  The <to-mixer> and <from-mixer> elements have the
      <controls> child element:
      *  Controls that apply to a specific user would appear under the
         <controls> element.

4.7.  <sidebars-by-ref>

   The <sidebars-by-ref> element contains a set of <entry> child
   elements.  This element is described in [RFC4575], 5.9.1.  Note that
   the <sidebars-by-ref> element does not have the attribute 'state'
   defined in [RFC4575] for this element because this attribute only
   applies to notifications mechanism.

4.8.  <sidebars-by-val>

   The <sidebars-by-val> element contains a set of <entry> child
   elements each containing information about a single sidebar.  This
   element is described in [RFC4575], 5.9.2.  Note that the <sidebars-
   by-val> element does not have the attribute 'state' defined in
   [RFC4575] for this element because this attribute only applies to
   notifications mechanism.


5.  RELAX NG Schema

   In accordance with the Centralized Conferencing Framework document
   [RFC5239], the Conference Object is a logical representation of a
   conference instance.  The conference information schema contains core
   information that is utilized in any conference.  It also contains the
   variable information part of the Conference Object.

   The normative schema is backwards compatible with the [RFC5239], in
   other words, valid [RFC5239] instance documents are also valid
   according to this RELAX NG schema [RELAX].  In addition to
   approximately similar RELAX NG [RELAX] definitions of the [RFC5239],
   this schema contains extension elements in the
   "urn:ietf:params:xml:ns:xcon-conference-info" namespace.



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 default namespace = "urn:ietf:params:xml:ns:conference-info"
 namespace xcon = "urn:ietf:params:xml:ns:xcon-conference-info"

 start = element conference-info { conference-type }
 # CONFERENCE TYPE
 conference-type =
   attribute entity { text }
   & anyAttribute
   & conference-description-type?
   & element host-info { host-type }?
   & element conference-state { conference-state-type }?
   & element users { users-type }?
   & element sidebars-by-ref { uris-type }?
   & element sidebars-by-val { sidebars-by-val-type }?
   & element xcon:floor-information { floor-information-type }?
   & anyElement*
 # CONFERENCE DESCRIPTION TYPE
 conference-description-type =
   element conference-description {
     attribute xml:lang { xsd:language }?
     & anyAttribute
     & element display-text { text }?
     & element subject { text }?
     & element free-text { text }?
     & element keywords {
         list { xsd:string* }
       }?
     & element conf-uris { uris-type }?
     & element service-uris { uris-type }?
     & element maximum-user-count { xsd:int }?
     & element available-media { conference-media-type }?
     & element xcon:language { xsd:language }?
     & element xcon:allow-sidebars { xsd:boolean }?
     & element xcon:cloning-parent { xsd:anyURI }?
     & element xcon:sidebar-parent { xsd:anyURI }?
     & element xcon:conference-time { conferencetime-type }?
     & anyElement*
   }
 # HOST TYPE
 host-type =
   element display-text { text }?
   & element web-page { xsd:anyURI }?
   & element uris { uris-type }?
   & anyElement*
   & anyAttribute
 # CONFERENCE STATE TYPE
 conference-state-type =
   anyAttribute



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   & element user-count { xsd:unsignedInt }?
   & element active { xsd:boolean }?
   & element locked { xsd:boolean }?
   & element xcon:allow-conference-event-subscription { xsd:boolean }?
   & anyElement*
 # CONFERENCE MEDIA TYPE
 conference-media-type =
   anyAttribute
   & element entry { conference-medium-type }*
   & anyElement*
 # CONFERENCE MEDIUM TYPE
 conference-medium-type =
   attribute label { text }
   & anyAttribute
   & element display-text { text }?
   & element type { text }?
   & element status { media-status-type }?
   & element xcon:mixing-mode { mixing-mode-type }?
   & element xcon:codecs { codecs-type }?
   & element xcon:controls { control-type }?
   & anyElement*
 # URIs TYPE
 uris-type =
   anyAttribute
   & element entry { uri-type }*
   & anyElement*
 # URI TYPE
 uri-type =
   element uri { xsd:anyURI }
   & element display-text { text }?
   & element purpose { text }?
   & element modified { execution-type }?
   & element xcon:conference-password { text }*
   & anyElement*
   & anyAttribute
 # USERS TYPE
 users-type =
   anyAttribute
   & element user { user-type }*
   & element xcon:join-handling { join-handling-type }?
   & element xcon:user-admission-policy { user-admission-policy-type }?
   & element xcon:allowed-users-list { allowed-users-list-type }?
   & element xcon:deny-users-list { deny-user-list-type }?
   & anyElement*
 # USER TYPE
 user-type =
   attribute entity { xsd:anyURI }
   & anyAttribute



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   & element display-text { text }?
   & element associated-aors { uris-type }?
   & element roles {
       element entry { single-role-type }+
     }?
   & element languages {
       list { xsd:language }
     }?
   & element cascaded-focus { xsd:anyURI }?
   & element endpoint { endpoint-type }*
   & element xcon:provide-anonymity { provide-anonymity-type }?
   & element xcon:allow-refer-users-dynamically { xsd:boolean }?
   & element xcon:allow-invite-users-dynamically { xsd:boolean }?
   & element xcon:allow-remove-users-dynamically { xsd:boolean }?
   & anyElement*
 # ENDPOINT TYPE
 endpoint-type =
   attribute entity { text }
   & anyAttribute
   & element display-text { text }?
   & element referred { execution-type }?
   & element status { endpoint-status-type }?
   & element joining-method { joining-type }?
   & element joining-info { execution-type }?
   & element disconnection-method { disconnection-type }?
   & element disconnection-info { execution-type }?
   & element media { media-type }*
   & element call-info { call-type }?
   & element xcon:floor {
       attribute id { text },
       anyAttribute,
       xsd:boolean
     }*
   & anyElement*
 # ENDPOINT STATUS TYPE
 endpoint-status-type =
   "pending"
   | "dialing-out"
   | "dialing-in"
   | "alerting"
   | "on-hold"
   | "connected"
   | "muted-via-focus"
   | "disconnecting"
   | "disconnected"
   | free-text-extension
 # JOINING TYPE
 joining-type =



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   "dialed-in" | "dialed-out" | "focus-owner" | free-text-extension
 # DISCONNECTION TYPE
 disconnection-type =
   "departed" | "booted" | "failed" | "busy" | free-text-extension
 # EXECUTION TYPE
 execution-type =
   element when { xsd:dateTime }?
   & element reason { text }?
   & element by { xsd:anyURI }?
   & anyAttribute
 # CALL TYPE
 call-type =
   element sip { sip-dialog-id-type }
   & anyElement*
   & anyAttribute
 # SIP DIALOG ID TYPE
 sip-dialog-id-type =
   element display-text { text }?
   & element call-id { text }
   & element from-tag { text }
   & element to-tag { text }
   & anyElement*
   & anyAttribute
 # MEDIA TYPE
 media-type =
   attribute id { xsd:int }
   & anyAttribute
   & element display-text { text }?
   & element type { text }?
   & element label { text }?
   & element src-id { text }?
   & element status { media-status-type }?
   & element xcon:to-mixer { mixer-type }?
   & element xcon:from-mixer { mixer-type }?
   & anyElement*
 # MEDIA STATUS TYPE
 media-status-type =
   "recvonly"
   | "sendonly"
   | "sendrecv"
   | "inactive"
   | free-text-extension
 # SIDEBARS-BY-VAL TYPE
 sidebars-by-val-type =
   anyAttribute
   & element entry { conference-type }*
   & anyElement*
 # CONFERENCE TIME



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 conferencetime-type =
   anyAttribute
   & element xcon:entry {
       element xcon:base { text },
       element xcon:mixing-start-offset {
         time-type,
         attribute required-participant { single-role-type },
         anyAttribute
       }?,
       element xcon:mixing-end-offset {
         time-type,
         attribute required-participant { single-role-type },
         anyAttribute
       }?,
       element xcon:can-join-after-offset { time-type }?,
       element xcon:must-join-before-offset { time-type }?,
       element xcon:request-user { time-type }?,
       element xcon:notify-end-of-conference { xsd:int }?,
       element xcon:allowed-extend-mixing-end-offset { xsd:boolean }?,
       anyElement*
     }*
 # TIME TYPE
 time-type = xsd:dateTime { pattern = ".+T.+Z.*" }
 # SINGLE ROLE TYPE
 single-role-type =
   xsd:string "none"
   | xsd:string "administrator"
   | xsd:string "moderator"
   | xsd:string "user"
   | xsd:string "observer"
   | xsd:string "participant"
   | free-text-extension
 # MIXING MODE TYPE
 mixing-mode-type =
   xsd:string "moderator-controlled"
   | xsd:string "FCFS"
   | xsd:string "automatic"
   | free-text-extension
 # CODECS TYPE
 codecs-type =
   attribute decision { decision-type }
   & anyAttribute
   & element xcon:codec { codec-type }*
   & anyElement*
 # CODEC TYPE
 codec-type =
   attribute name { text }
   & attribute policy { policy-type }



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   & anyAttribute
   & element xcon:subtype { text }?
   & anyElement*
 # DECISION TYPE
 decision-type =
   xsd:string "automatic"
   | xsd:string "moderator-controlled"
   | free-text-extension
 # POLICY TYPE
 policy-type =
   xsd:string "allowed" | xsd:string "disallowed" | free-text-extension
 # CONTROL TYPE
 control-type =
   anyAttribute
   & element xcon:mute { xsd:boolean }?
   & element xcon:pause-video { xsd:boolean }?
   & element xcon:gain { gain-type }?
   & element xcon:video-layout { video-layout-type }?
   & anyElement*
 # GAIN TYPE
 gain-type = xsd:int { minInclusive = "-127" maxInclusive = "127" }
 # VIDEO LAYOUT TYPE
 video-layout-type =
   xsd:string "single-view"
   | xsd:string "dual-view"
   | xsd:string "dual-view-crop"
   | xsd:string "dual-view-2x1"
   | xsd:string "dual-view-2x1-crop"
   | xsd:string "quad-view"
   | xsd:string "multiple-3x3"
   | xsd:string "multiple-4x4"
   | xsd:string "multiple-5x1"
   | xsd:string "automatic"
   | free-text-extension
 # FLOOR INFORMATION TYPE
 floor-information-type =
   anyAttribute
   & element xcon:conference-ID { xsd:unsignedLong }?
   & element xcon:allow-floor-events { xsd:boolean }?
   & element xcon:floor-request-handling { floor-request-type }?
   & element xcon:conference-floor-policy { conference-floor-policy }?
   & anyElement*
 # FLOOR REQUEST TYPE
 floor-request-type =
   xsd:string "block" | xsd:string "confirm" | free-text-extension
 # CONFERENCE FLOOR POLICY
 conference-floor-policy =
   anyAttribute



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   & element xcon:floor {
       attribute id { text }
       & anyAttribute
       & element xcon:media-label { xsd:nonNegativeInteger }+
       & element xcon:algorithm { algorithm-type }?
       & element xcon:max-floor-users { xsd:nonNegativeInteger }?
       & element xcon:moderator-id { xsd:nonNegativeInteger }?
       & anyElement*
     }+
 # ALGORITHM POLICY
 algorithm-type =
   xsd:string "moderator-controlled"
   | xsd:string "FCFS"
   | xsd:string "random"
   | free-text-extension
 # USERS ADMISSION POLICY
 user-admission-policy-type =
   xsd:string "closedAuthenticated"
   | xsd:string "openAuthenticated"
   | xsd:string "anonymous"
   | free-text-extension
 # JOIN HANDLING TYPE
 join-handling-type =
   xsd:string "block"
   | xsd:string "confirm"
   | xsd:string "allow"
   | xsd:string "authenticate"
   | xsd:string "directed-operator"
   | free-text-extension
 # DENY USERLIST
 deny-user-list-type =
   anyAttribute
   & element xcon:target {
       attribute uri { xsd:anyURI },
       anyAttribute
     }*
   & anyElement*
 # ALLOWED USERS LIST TYPE
 allowed-users-list-type =
   anyAttribute
   & element xcon:target { target-type }*
   & element xcon:persistent-list { persistent-list-type }?
   & anyElement*
 # PERSISTENT LIST TYPE
 persistent-list-type =
   element xcon:user {
     attribute name { text }
     & attribute nickname { text }



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     & attribute id { text }
     & anyAttribute
     & element xcon:e-mail { text }*
     & anyElement*
   }*
   & anyElement*
 # TARGET TYPE
 target-type =
   attribute uri { xsd:anyURI },
   attribute method { method-type },
   anyAttribute
 # METHOD TYPE
 method-type =
   xsd:string "dial-in"
   | xsd:string "dial-out"
   | xsd:string "refer"
   | free-text-extension
 # ANONYMITY TYPE
 provide-anonymity-type =
   "private" | "semi-private" | "hidden" | free-text-extension
 # MIXER TYPE
 mixer-type =
   attribute name { mixer-name-type }
   & anyAttribute
   & element xcon:controls { control-type }*
   & anyElement*
 # MIXER NAME TYPE
 mixer-name-type =
   "VideoIn" | "VideoOut" | "AudioOut" | "AudioIn" | free-text-extension

 # FREE TEXT EXTENSION
 # (re-define this as <notAllowed/>,
 #  if extensions beyond this spec are not used)

 free-text-extension = text

 # *********************************
 # EXTENSIBILITY OF THE SCHEMA
 # *********************************

 # EXTENSIBILITY ELEMENTS
 # (re-define this as <empty/>,
 #  if extensions beyond this spec are not used)

 anyElement =
   element * - (conference-description
                | host-info
                | conference-state



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                | users
                | sidebars-by-ref
                | sidebars-by-val
                | display-text
                | subject
                | free-text
                | keywords
                | conf-uris
                | service-uris
                | maximum-user-count
                | available-media
                | web-page
                | uris
                | uri
                | user-count
                | active
                | locked
                | entry
                | type
                | status
                | purpose
                | modified
                | user
                | associated-aors
                | roles
                | languages
                | cascaded-focus
                | endpoint
                | referred
                | joining-method
                | joining-info
                | disconnection-method
                | disconnection-info
                | media
                | call-info
                | when
                | reason
                | by
                | sip
                | call-id
                | from-tag
                | to-tag
                | label
                | src-id
                | xcon:conference-password
                | xcon:mixing-mode
                | xcon:codecs
                | xcon:controls



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                | xcon:language
                | xcon:allow-sidebars
                | xcon:cloning-parent
                | xcon:sidebar-parent
                | xcon:allow-conference-event-subscription
                | xcon:to-mixer
                | xcon:provide-anonymity
                | xcon:allow-refer-users-dynamically
                | xcon:allow-invite-users-dynamically
                | xcon:allow-remove-users-dynamically
                | xcon:from-mixer
                | xcon:join-handling
                | xcon:user-admission-policy
                | xcon:allowed-users-list
                | xcon:deny-users-list
                | xcon:floor-information
                | xcon:conference-time
                | xcon:provide-anonymity
                | xcon:floor
                | xcon:entry
                | xcon:mixing-start-offset
                | xcon:mixing-end-offset
                | xcon:can-join-after-offset
                | xcon:must-join-before-offset
                | xcon:request-user
                | xcon:notify-end-of-conference
                | xcon:allowed-extend-mixing-end-offset
                | xcon:codec
                | xcon:subtype
                | xcon:mute
                | xcon:pause-video
                | xcon:gain
                | xcon:video-layout
                | xcon:conference-ID
                | xcon:allow-floor-events
                | xcon:floor-request-handling
                | xcon:conference-floor-policy
                | xcon:media-label
                | xcon:algorithm
                | xcon:max-floor-users
                | xcon:moderator-id
                | xcon:target
                | xcon:persistent-list
                | xcon:e-mail
                | xcon:user) { anyExtension }
 anyExtension =
   (attribute * { text }
    | any)*



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 any =
   element * {
     (attribute * { text }
      | text
      | any)*
   }

 # EXTENSIBILITY ATTRIBUTES
 # (re-define this as <empty/>,
 #  if extensions beyond this spec are not used)

 anyAttribute =
   attribute * - (xml:lang
                  | entity
                  | required-participant
                  | label
                  | decision
                  | name
                  | policy
                  | uri
                  | method
                  | id
                  | nickname) { text }*


6.  XML Schema Extensibility

   The Conference Information Data Model defined in this document is
   meant to be extensible toward specific application domains.  Such
   extensions are accomplished by defining elements, child elements and
   attributes that are specific to the desired application domain.  The
   IETF MAY extend the data model schema with unqualified attributes or
   extension elements from the "urn:ietf:params:xml:ns:" "sub-namespace"
   in the future.  Other instances are free to define extension elements
   or attributes under other namespaces.

   Elements or attributes from unknown namespaces MUST be ignored.


7.  XML Example

   The following is an example of a conference information document.
   The conference starts on October 17, 2007, at 10:30 AM in New York
   City and finishes the same day at 12:30 PM every week.  In this
   example, there are currently 3 participants in a conference, one
   administrator, one moderator, and one participant.  Sidebars are
   allowed in this conference and ,consequently, there is one sidebar in
   the conference.  In addition, Alice and Carol are using a floor in



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   the main conference to manage the audio and video resources.  At the
   moment, Alice is assigned to use the floor.

<?xml version="1.0" encoding="UTF-8"?>
<conference-info
        xmlns="urn:ietf:params:xml:ns:conference-info"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
        entity="conference123@example.com">
        <!--
            CONFERENCE DESCRIPTION
        -->
        <conference-description xml:lang="en-us">
            <display-text>Discussion of Formula-1 racing</display-text>
            <subject>Sports:Formula-1</subject>
            <free-text>This is a conference example</free-text>
            <keywords>Formula-1 cars</keywords>
            <!--
                CONFERENCE UNIQUE IDENTIFIERS
            -->
            <conf-uris>
                <entry>
                    <uri>tel:+3585671234</uri>
                    <display-text>Conference Bridge</display-text>
                    <purpose>participation</purpose>
                    <xcon:conference-password
                     >5678</xcon:conference-password>
                </entry>
                <entry>
                    <uri>http://www.example.com/live.ram</uri>
                    <purpose>streaming</purpose>
                </entry>
            </conf-uris>
            <!--
                SERVICE URIS
            -->
            <service-uris>
                <entry>
                    <uri>mailto:bob@example.com</uri>
                    <display-text>email</display-text>
                </entry>
            </service-uris>
            <!--
                MAXIMUM USER COUNT
            -->
            <maximum-user-count>50</maximum-user-count>
            <!--
                AVAILABLE MEDIA
            -->



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            <available-media>
                <entry label="10234">
                    <display-text>main audio</display-text>
                    <type>audio</type>
                    <status>sendrecv</status>
                    <xcon:mixing-mode>automatic</xcon:mixing-mode>
                    <xcon:codecs decision="automatic">
                        <xcon:codec name="122" policy="allowed">
                           <xcon:subtype>PCMU</xcon:subtype>
                        </xcon:codec>
                    </xcon:codecs>
                    <xcon:controls>
                        <xcon:mute>true</xcon:mute>
                        <xcon:gain>50</xcon:gain>
                    </xcon:controls>
                </entry>
                <entry label="10235">
                    <display-text>main video</display-text>
                    <type>video</type>
                    <status>sendrecv</status>
                    <xcon:mixing-mode>automatic</xcon:mixing-mode>
                    <xcon:codecs decision="automatic">
                        <xcon:codec name="123" policy="allowed">
                           <xcon:subtype>H.263</xcon:subtype>
                        </xcon:codec>
                    </xcon:codecs>
                    <xcon:controls>
                        <xcon:video-layout
                          >single-view</xcon:video-layout>
                    </xcon:controls>
                </entry>
            </available-media>

            <xcon:language>En-us</xcon:language>

            <xcon:allow-sidebars>true</xcon:allow-sidebars>
            <!--
                CONFERENCE TIME
            -->

            <xcon:conference-time>
                <xcon:entry>
                    <xcon:base>BEGIN:VCALENDAR
  PRODID:-//LlamaSpinner Inc.//NONSGML CamelCall//EN
  VERSION:2.0
  BEGIN:VEVENT
  DTSTAMP:20071003T140728Z
  UID:20071003T140728Z-345FDA-carol@example.com



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  ORGANIZER:MAILTO:carol@example.com
  DTSTART:20071017T143000Z
  RRULE:FREQ=WEEKLY
  DTEND:20071217T163000Z
  END:VEVENT
  END:VCALENDAR</xcon:base>
                    <xcon:mixing-start-offset
                        required-participant="moderator"
                       >2007-10-17T14:29:00Z</xcon:mixing-start-offset>
                    <xcon:mixing-end-offset
                        required-participant="participant"
                       >2007-10-17T16:31:00Z</xcon:mixing-end-offset>
                    <xcon:must-join-before-offset
                       >2007-10-17T15:30:00Z
                       </xcon:must-join-before-offset>
                </xcon:entry>
            </xcon:conference-time>

        </conference-description>
        <!--
            HOST INFO
        -->
        <host-info>
            <display-text>Formula1</display-text>
            <web-page>http://www.example.com/formula1/</web-page>
            <uris>
                <entry>
                    <uri>sip:alice@example.com</uri>
                </entry>
                <entry>
                    <uri>sip:carol@example.com</uri>
                </entry>
            </uris>
        </host-info>
        <!--
            CONFERENCE STATE
        -->
        <conference-state>
            <user-count>3</user-count>
            <active>true</active>
            <locked>false</locked>
            <xcon:allow-conference-event-subscription
              >true</xcon:allow-conference-event-subscription>

       </conference-state>
        <!--
            USERS
        -->



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        <users>
            <!--
                USER BOB
            -->
            <user entity="xcon-userid:bob534">
                <display-text>Bob Hoskins</display-text>
                <associated-aors>
                    <entry>
                        <uri>mailto:bob@example.com</uri>
                        <display-text>email</display-text>
                    </entry>
                </associated-aors>
                <roles>
                    <entry>participant</entry>
                </roles>
                <languages>en-us</languages>

                <!--
                    ENDPOINTS
                -->
                <endpoint entity="sip:bob@example.com">
                    <display-text>Bob's Laptop</display-text>
                    <referred>
                        <when>2007-10-17T14:00:00Z</when>
                        <reason>expert required</reason>
                        <by>sip:alice@example.com</by>
                    </referred>
                    <status>connected</status>
                    <joining-method>dialed-out</joining-method>
                    <joining-info>
                        <when>2007-10-17T14:00:00Z</when>
                        <reason>invitation</reason>
                        <by>sip:alice@example.com</by>
                    </joining-info>
                    <!--
                        MEDIA
                    -->
                    <media id="1">
                        <type>video</type>
                        <label>10235</label>
                        <src-id>432424</src-id>
                        <status>sendrecv</status>
                        <xcon:to-mixer name="VideoIn">
                            <xcon:controls>
                                <xcon:video-layout
                                   >single-view</xcon:video-layout>
                            </xcon:controls>
                        </xcon:to-mixer>



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                    </media>
                    <!--
                        CALL INFO
                    -->
                    <call-info>
                        <sip>
                            <display-text>full info</display-text>
                            <call-id>hsjh8980vhsb78</call-id>
                            <from-tag>vav738dvbs</from-tag>
                            <to-tag>8954jgjg8432</to-tag>
                        </sip>
                    </call-info>
                </endpoint>
                <xcon:provide-anonymity
                 >semi-private</xcon:provide-anonymity>
                 <xcon:allow-refer-users-dynamically
                    >false</xcon:allow-refer-users-dynamically>
                <xcon:allow-invite-users-dynamically
                    >false</xcon:allow-invite-users-dynamically>
                <xcon:allow-remove-users-dynamically
                    >false</xcon:allow-remove-users-dynamically>
            </user>

            <!--
                USER ALICE
            -->
            <user entity="xcon-userid:alice334">
                <display-text>Alice Kay</display-text>
                <associated-aors>
                    <entry>
                        <uri>mailto:alice@example.com</uri>
                        <display-text>email</display-text>
                    </entry>
                </associated-aors>
                <roles>
                    <entry>moderator</entry>
                </roles>
                <languages>en-us</languages>
                <!--
                    ENDPOINTS
                -->
                <endpoint entity="sip:alice@example.com">
                    <display-text>Alice's Desktop</display-text>
                    <status>connected</status>
                    <joining-method>dialed-in</joining-method>
                    <joining-info>
                        <when>2007-10-17T13:35:08Z</when>
                        <reason>invitation</reason>



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                        <by>sip:conference@example.com</by>
                    </joining-info>
                    <!--
                        MEDIA
                    -->
                    <media id="1">
                        <type>video</type>
                        <label>10235</label>
                        <src-id>432424</src-id>
                        <status>sendrecv</status>
                        <xcon:to-mixer name="VideoIn">
                         <xcon:controls>
                            <xcon:video-layout
                              >single-view</xcon:video-layout>
                         </xcon:controls>
                        </xcon:to-mixer>
                    </media>
                    <media id="2">
                        <type>audio</type>
                        <label>10234</label>
                        <src-id>532535</src-id>
                        <status>sendrecv</status>
                        <xcon:to-mixer name="AudioIn">
                          <xcon:controls>
                            <xcon:gain>50</xcon:gain>
                          </xcon:controls>
                        </xcon:to-mixer>
                        <xcon:from-mixer name="AudioOut">
                          <xcon:controls>
                              <xcon:gain>50</xcon:gain>
                          </xcon:controls>
                        </xcon:from-mixer>
                    </media>
                    <!--
                        CALL INFO
                    -->
                    <call-info>
                        <sip>
                            <display-text>full info</display-text>
                            <call-id>truy45469123478</call-id>
                            <from-tag>asd456cbgt</from-tag>
                            <to-tag>3456jgjg1234</to-tag>
                        </sip>
                    </call-info>
                    <xcon:floor id="345">true</xcon:floor>
                </endpoint>
                <xcon:provide-anonymity>private</xcon:provide-anonymity>
                <xcon:allow-refer-users-dynamically



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                    >true</xcon:allow-refer-users-dynamically>
                <xcon:allow-invite-users-dynamically
                    >true</xcon:allow-invite-users-dynamically>
                <xcon:allow-remove-users-dynamically
                    >true</xcon:allow-remove-users-dynamically>
            </user>

            <!--
                USER CAROL
            -->
            <user entity="xcon-userid:carol233">
                <display-text>Carol More</display-text>
                <associated-aors>
                    <entry>
                        <uri>mailto:carol@example.com</uri>
                        <display-text>email</display-text>
                    </entry>
                </associated-aors>
                <roles>
                    <entry>administrator</entry>
                </roles>
                <languages>en-us</languages>
                <!--
                    ENDPOINTS
                -->
                <endpoint entity="sip:carol@example.com">
                    <display-text>Carol's Computer</display-text>
                    <status>connected</status>
                    <joining-method>dialed-in</joining-method>
                    <joining-info>
                        <when>2007-10-17T13:30:05Z</when>
                        <reason>invitation</reason>
                        <by>sip:conference@example.com</by>
                    </joining-info>
                    <!--
                        MEDIA
                    -->
                    <media id="1">
                        <type>video</type>
                        <label>10235</label>
                        <src-id>432424</src-id>
                        <status>sendrecv</status>
                        <xcon:to-mixer name="VideoIn">
                            <xcon:controls>
                                <xcon:video-layout
                              >single-view</xcon:video-layout>
                         </xcon:controls>
                        </xcon:to-mixer>



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                    </media>
                    <media id="2">
                        <type>audio</type>
                        <label>10234</label>
                        <src-id>532535</src-id>
                        <status>sendrecv</status>
                        <xcon:to-mixer name="AudioIn">
                            <xcon:controls>
                                <xcon:gain>50</xcon:gain>
                            </xcon:controls>
                        </xcon:to-mixer>
                        <xcon:from-mixer name="AudioOut">
                            <xcon:controls>
                                <xcon:gain>50</xcon:gain>
                          </xcon:controls>
                        </xcon:from-mixer>
                    </media>
                    <!--
                        CALL INFO
                    -->
                    <call-info>
                        <sip>
                            <display-text>full info</display-text>
                            <call-id>wevb12562321894</call-id>
                            <from-tag>asw456wedf</from-tag>
                            <to-tag>2365dfrt3497</to-tag>
                        </sip>
                    </call-info>

                    <xcon:floor id="345">false</xcon:floor>
                </endpoint>

                <xcon:provide-anonymity>private</xcon:provide-anonymity>
                <xcon:allow-refer-users-dynamically
                    >true</xcon:allow-refer-users-dynamically>
                <xcon:allow-invite-users-dynamically
                    >true</xcon:allow-invite-users-dynamically>
                <xcon:allow-remove-users-dynamically
                    >true</xcon:allow-remove-users-dynamically>

            </user>

            <xcon:join-handling>allow</xcon:join-handling>
            <xcon:user-admission-policy
               >openAuthenticated</xcon:user-admission-policy>
            <!--
                ALLOWED USERS LIST
            -->



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            <xcon:allowed-users-list>
                <xcon:target uri="sip:bob@example.com"
                    method="dial-out"/>
                <xcon:target uri="sip:alice@example.com"
                    method="dial-out"/>
                <xcon:target uri="sip:carol@example.com"
                    method="dial-out"/>
                <xcon:target uri="sip:john@example.com"
                    method="refer"/>
            </xcon:allowed-users-list>
            <!--
                DENY USERS LIST
            -->
            <xcon:deny-users-list>
                <xcon:target uri="sip:charlie@example.com"/>
            </xcon:deny-users-list>
        </users>
        <!--
            SIDEBARS BY REFERENCE
        -->
        <sidebars-by-ref>
            <entry>
                <uri>xcon:conf223</uri>
                <display-text>private with Bob</display-text>
            </entry>
        </sidebars-by-ref>
        <!--
            SIDEBARS BY VALUE
        -->
        <sidebars-by-val>
            <entry entity="conf223">
                <users>
                    <user entity="xcon-userid:bob534"/>
                    <user entity="xcon-userid:carol233"/>
                </users>
            </entry>
        </sidebars-by-val>
        <!--
            FLOOR INFORMATION
        -->
        <xcon:floor-information>
            <xcon:conference-ID>567</xcon:conference-ID>
            <xcon:allow-floor-events>true</xcon:allow-floor-events>
            <xcon:floor-request-handling
             >confirm</xcon:floor-request-handling>

            <xcon:conference-floor-policy>
                <xcon:floor id="345">



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                    <xcon:media-label>10234</xcon:media-label>
                    <xcon:media-label>10235</xcon:media-label>
                    <xcon:algorithm
                     >moderator-controlled</xcon:algorithm>
                    <xcon:max-floor-users>1</xcon:max-floor-users>
                    <xcon:moderator-id>234</xcon:moderator-id>
                </xcon:floor>
            </xcon:conference-floor-policy>
        </xcon:floor-information>

    </conference-info>

   Note that due to RFC formatting conventions, this documents splits
   lines whose content would exceed 72 characters.


8.  Security Considerations

   There are numerous security considerations for this document.  This
   section discusses them.

   This specification defines a data model for conference objects.
   Different conferencing systems may use different protocols to provide
   access to these conference objects.  This section contains general
   security considerations for the conference objects and for the
   protocols.  The specification of each particular protocol needs to
   discuss how the specific protocol meets the security requirements
   provided in this section.

   A given conferencing system usually supports different protocols in
   order to implement different functions (e.g., SIP for session control
   and BFCP for floor control).  Each of these protocols may use their
   own authentication mechanism.  In cases where a user is authenticated
   using multiple authentication mechanisms, it is up to the
   conferencing system to map all the different authentications to the
   same user.  Discussing the specifics of different authentication
   mechanism is beyond the scope of this document.

   Futhermore, users may use different namespaces to access to a
   conference as explained in Section 4.6.5.  These different namespaces
   can be associated with a unique conference user identifier (XCON-
   USERID).  A mapping database is used to map all these authenticated
   user namespaces to the XCON-USERID.  There are several threats
   against this database.  In order to minimize these threats, the
   administrator of the conferencing system MUST ensure that only
   authorized users can connect to this database (e.g., by using access
   control rules).  In particular, the integrity of the database MUST be
   protected against unauthorized modifications.



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   The confidentiality of the database SHOULD be protected from
   unauthorized users, given that the data model contains a set of
   sensitive elements (e.g., passwords).  Therefore, in addition to
   implementing access control, as discussed above, it is RECOMMENDED
   that administrators of conferencing systems only provide access to
   the database over encrypted channels (e.g., using TLS encryption) in
   order to avoid eavesdroppers.  Administrators of conferencing systems
   SHOULD also avoid disclosing information to unauthorized parties when
   a conference is being cloned or when a sidebar is being created.

   The security considerations for authentication (Section 11.1)
   described in the centralized conferencing framework [RFC5239] also
   apply to this document.  Similarly, the security considerations for
   authorization (Section 5.2) described in the Session Initiation
   Protocol (SIP) REFER Method [RFC3515] apply to this document as well.


9.  IANA Considerations

9.1.  Relax NG Schema Registration


  This specification registers a schema. The schema can be found
  as the sole content of Section 5.

     URI:  urn:ietf:params:xml:ns:xcon-conference-info

     Registrant Contact: IETF XCON working group,
        <xcon@ietf.org>, Oscar Novo
        <Oscar.Novo@ericsson.com>

     Relax NG Schema:  The Relax NG schema to be registered is contained
        in Section 5.  Its first line is

     default namespace = "urn:ietf:params:xml:ns:conference-info"

        and its last line is

     anyAttribute = attribute * - (xml:lang | entity
                    | required-participant | label | decision | name
                    | policy | uri | method | id | nickname) { text }*










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9.2.  XML Namespace Registration



   This section registers a new XML namespace.

      URI:  urn:ietf:params:xml:ns:xcon-conference-info

      Registrant Contact: IETF XCON working group,
         <xcon@ietf.org>, Oscar Novo
         <Oscar.Novo@ericsson.com>

       XML:

         BEGIN
         <?xml version="1.0"?>
         <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
           "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
         <html xmlns="http://www.w3.org/1999/xhtml">
         <head>
           <meta http-equiv="content-type"
                 content="text/html;charset=iso-8859-1"/>
           <title> Centralized Conferencing Namespace</title>
         </head>
         <body>
           <h1>Namespace for Centralized Conferencing</h1>
           <h2>urn:ietf:params:xml:ns:xcon-conference-info</h2>
         <p>See <a href="[URL of published RFC]">RFCXXXX
             [NOTE TO IANA/RFC-EDITOR:
              Please replace XXXX with the RFC number of this
             specification.]</a>.</p>
         </body>
         </html>
         END

9.3.  Conference Object Identifier Registration



 The IANA is requested to register the following URI scheme
 under the Permanent URI Schemes registry.

 XCON-URI = "xcon" ":" [conf-object-id "@"] host [ ":" port ] [RFC xxxx]

  conf-object-id = 1*( unreserved / "+" / "=" / "/" )


   host, port, and unreserved are defined in RFC3986[RFC3986]



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   [Note to the RFC Editor: replace xxxx with the number this RFC gets
   assigned.]



    Subject: Request for XCON-URI Registration
    Person & email address to contact for further information:
         Oscar Novo <oscar novo_at_ericsson.com>
    Specification: RFC XXXX
    Author/Change Controller: IESG
    Comments:
        Identifies the Conference

9.4.  Conference User Identifier Registration



   The IANA is requested to register the following URI scheme
    under the Permanent URI Schemes registry.

    XCON-USERID = "xcon-userid" ":" conf-user-id  [ RFC xxxx ]

    conf-user-id = 1*(unreserved)


   unreserved is defined in RFC3986[RFC3986]

   [Note to the RFC Editor: replace xxxx with the number this RFC gets
   assigned.]



    Subject: Request for XCON-USERID Registration
    Person & email address to contact for further information:
         Oscar Novo <oscar novo_at_ericsson.com>
    Specification: RFC XXXX
    Author/Change Controller: IESG
    Comments:
        Identifies the User in the conference


10.  Acknowledgements

   This document is really a distillation of many ideas discussed over a
   long period of time.  These ideas were contributed by many different
   drafts in the XCON working group and the SIPPING working group.  We
   would like to thank Orit Levin, Roni Even, Adam Roach, Mary Barnes,
   Chris Boulton, Umesh Chandra, Hisham Khartabil, Petri Koskelainen,



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   Aki Niemi, Rohan Mahy, Jonathan Lennox, Sean Duddy, Richard Barnes,
   and Henning Schulzrinne for their comments.  Also, we would like to
   thank Mary Barnes, and Chris Boulton for letting us use the
   conference and user identifier information of their xcon drafts.
   Last but not least, we would like to express our gratitude to all
   those reviewers for their invaluable contribution: Simon Pietro
   Romano, Lorenzo Miniero, Tobia Castaldi, Miguel Garcia, Mary Barnes,
   Srivatsa Srinivasan, Avshalom Houri, Pierre Tane, and Ben Campbell.


11.  References

11.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4575]  Rosenberg, J., Schulzrinne, H., and O. Levin, "A Session
              Initiation Protocol (SIP) Event Package for Conference
              State", RFC 4575, August 2006.

   [RFC4582]  Camarillo, G., Ott, J., and K. Drage, "The Binary Floor
              Control Protocol (BFCP)", RFC 4582, November 2006.

   [RFC4583]  Camarillo, G., "Session Description Protocol (SDP) Format
              for Binary Floor Control Protocol (BFCP) Streams",
              RFC 4583, November 2006.

   [RFC5239]  Barnes, M., Boulton, C., and O. Levin, "A Framework for
              Centralized Conferencing", RFC 5239, June 2008.

   [RFC5545]  Desruisseaux, B., "Internet Calendaring and Scheduling
              Core Object Specification (iCalendar)", RFC 5545,
              September 2009.

11.2.  Informative References

   [IANA]     "IANA registry for RTP Payload Types"
              "http://www.iana.org/assignments/rtp-parameters".

   [IANA-Lan]
              "IANA Language Subtag Registry"
              "http://www.iana.org/assignments/
              language-subtag-registry".

   [RELAX]    "RELAX NG Home Page" "http://relaxng.org/".

   [RFC3264]  Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model



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              with Session Description Protocol (SDP)", RFC 3264,
              June 2002.

   [RFC3265]  Roach, A., "Session Initiation Protocol (SIP)-Specific
              Event Notification", RFC 3265, June 2002.

   [RFC3515]  Sparks, R., "The Session Initiation Protocol (SIP) Refer
              Method", RFC 3515, April 2003.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, January 2005.

   [RFC4353]  Rosenberg, J., "A Framework for Conferencing with the
              Session Initiation Protocol (SIP)", RFC 4353,
              February 2006.

   [RFC4855]  Casner, S., "Media Type Registration of RTP Payload
              Formats", RFC 4855, February 2007.

   [RFC5018]  Camarillo, G., "Connection Establishment in the Binary
              Floor Control Protocol (BFCP)", RFC 5018, September 2007.

   [RFC5646]  Phillips, A. and M. Davis, "Tags for Identifying
              Languages", BCP 47, RFC 5646, September 2009.

   [W3C.REC-xml-20001006]
              Sperberg-McQueen, C., Bray, T., Paoli, J., and E. Maler,
              "Extensible Markup Language (XML) 1.0 (Second Edition)",
              World Wide Web Consortium FirstEdition REC-xml-20001006,
              October 2000,
              <http://www.w3.org/TR/2000/REC-xml-20001006>.


Appendix A.  Non-Normative RELAX NG Schema in XML Syntax

 <?xml version="1.0" encoding="UTF-8" ?>
    <grammar
           ns="urn:ietf:params:xml:ns:conference-info"
           xmlns="http://relaxng.org/ns/structure/1.0"
           xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
           datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
           <start>
            <element name="conference-info">
             <ref name="conference-type"/>
            </element>
           </start>
           <!--



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               CONFERENCE TYPE
           -->
           <define name="conference-type">
            <interleave>
            <attribute name="entity">
             <text/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <ref name="conference-description-type"/>
            </optional>
            <optional>
             <element name="host-info">
              <ref name="host-type"/>
             </element>
            </optional>
            <optional>
             <element name="conference-state">
              <ref name="conference-state-type"/>
             </element>
            </optional>
            <optional>
             <element name="users">
              <ref name="users-type"/>
             </element>
            </optional>
            <optional>
             <element name="sidebars-by-ref">
              <ref name="uris-type"/>
             </element>
            </optional>
            <optional>
             <element name="sidebars-by-val">
              <ref name="sidebars-by-val-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:floor-information">
              <ref name="floor-information-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               CONFERENCE DESCRIPTION TYPE



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           -->
           <define name="conference-description-type">
            <element name="conference-description">
             <interleave>
             <optional>
              <attribute name="xml:lang">
               <data type="language"/>
              </attribute>
             </optional>
             <ref name="anyAttribute"/>
             <optional>
              <element name="display-text">
               <text/>
              </element>
             </optional>
             <optional>
              <element name="subject">
               <text/>
              </element>
             </optional>
             <optional>
              <element name="free-text">
               <text/>
              </element>
             </optional>
             <optional>
              <element name="keywords">
               <list>
                <zeroOrMore>
                 <data type="string"/>
                </zeroOrMore>
               </list>
              </element>
             </optional>
             <optional>
              <element name="conf-uris">
               <ref name="uris-type"/>
              </element>
             </optional>
             <optional>
              <element name="service-uris">
                 <ref name="uris-type"/>
              </element>
             </optional>
             <optional>
              <element name="maximum-user-count">
               <data type="int"/>
              </element>



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             </optional>
             <optional>
              <element name="available-media">
               <ref name="conference-media-type"/>
              </element>
             </optional>
             <optional>
              <element name="xcon:language">
               <data type="language"/>
              </element>
             </optional>
             <optional>
              <element name="xcon:allow-sidebars">
               <data type="boolean"/>
              </element>
             </optional>
             <optional>
             <element name="xcon:cloning-parent">
              <data type="anyURI"/>
             </element>
             </optional>
             <optional>
             <element name="xcon:sidebar-parent">
              <data type="anyURI"/>
             </element>
             </optional>
             <optional>
              <element name="xcon:conference-time">
               <ref name="conferencetime-type"/>
              </element>
             </optional>
             <zeroOrMore>
              <ref name="anyElement"/>
             </zeroOrMore>
             </interleave>
            </element>
           </define>
           <!--
               HOST TYPE
           -->
           <define name="host-type">
            <interleave>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>



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             <element name="web-page">
              <data type="anyURI"/>
             </element>
            </optional>
            <optional>
             <element name="uris">
              <ref name="uris-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            <ref name="anyAttribute"/>
            </interleave>
           </define>
           <!--
               CONFERENCE STATE TYPE
           -->
           <define name="conference-state-type">
            <interleave>
            <ref name="anyAttribute"/>
            <optional>
             <element name="user-count">
              <data type="unsignedInt"/>
             </element>
            </optional>
            <optional>
             <element name="active">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="locked">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:allow-conference-event-subscription">
              <data type="boolean"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               CONFERENCE MEDIA TYPE



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           -->
           <define name="conference-media-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="entry">
              <ref name="conference-medium-type"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               CONFERENCE MEDIUM TYPE
           -->
           <define name="conference-medium-type">
            <interleave>
            <attribute name="label">
             <text/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="type">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="status">
              <ref name="media-status-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:mixing-mode">
              <ref name="mixing-mode-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:codecs">
              <ref name="codecs-type"/>
             </element>
            </optional>



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            <optional>
             <element name="xcon:controls">
              <ref name="control-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               URIs TYPE
           -->
           <define name="uris-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="entry">
              <ref name="uri-type"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               URI TYPE
           -->
           <define name="uri-type">
            <interleave>
            <element name="uri">
             <data type="anyURI"/>
            </element>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="purpose">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="modified">
              <ref name="execution-type"/>
             </element>



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            </optional>
            <zeroOrMore>
             <element name="xcon:conference-password">
              <text/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            <ref name="anyAttribute"/>
           </interleave>

           </define>
           <!--
               USERS TYPE
           -->
           <define name="users-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="user">
              <ref name="user-type"/>
             </element>
            </zeroOrMore>
            <optional>
             <element name="xcon:join-handling">
              <ref name="join-handling-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:user-admission-policy">
              <ref name="user-admission-policy-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:allowed-users-list">
              <ref name="allowed-users-list-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:deny-users-list">
              <ref name="deny-user-list-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>



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           </define>
           <!--
               USER TYPE
           -->
           <define name="user-type">
            <interleave>
            <attribute name="entity">
             <data type="anyURI"/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="associated-aors">
               <ref name="uris-type"/>
             </element>
            </optional>
            <optional>
             <element name="roles">
              <oneOrMore>
               <element name="entry">
                <ref name="single-role-type"/>
               </element>
              </oneOrMore>
             </element>
            </optional>
            <optional>
             <element name="languages">
              <list>
               <data type="language"/>
              </list>
             </element>
            </optional>
            <optional>
             <element name="cascaded-focus">
              <data type="anyURI"/>
             </element>
            </optional>
            <zeroOrMore>
             <element name="endpoint">
              <ref name="endpoint-type"/>
             </element>
            </zeroOrMore>
            <optional>
             <element name="xcon:provide-anonymity">



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              <ref name="provide-anonymity-type"/>
             </element>
            </optional>
           <optional>
             <element name="xcon:allow-refer-users-dynamically">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:allow-invite-users-dynamically">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:allow-remove-users-dynamically">
              <data type="boolean"/>
             </element>
            </optional>
             <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               ENDPOINT TYPE
           -->
           <define name="endpoint-type">
            <interleave>
            <attribute name="entity">
             <text/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="referred">
               <ref name="execution-type"/>
             </element>
            </optional>
            <optional>
             <element name="status">
              <ref name="endpoint-status-type"/>
             </element>
            </optional>
            <optional>



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             <element name="joining-method">
              <ref name="joining-type"/>
             </element>
            </optional>
            <optional>
             <element name="joining-info">
               <ref name="execution-type"/>
             </element>
            </optional>
            <optional>
             <element name="disconnection-method">
              <ref name="disconnection-type"/>
             </element>
            </optional>
            <optional>
             <element name="disconnection-info">
              <ref name="execution-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <element name="media">
              <ref name="media-type"/>
             </element>
            </zeroOrMore>
            <optional>
             <element name="call-info">
              <ref name="call-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <element name="xcon:floor">
              <attribute name="id">
               <text/>
              </attribute>
              <ref name="anyAttribute"/>
              <data type="boolean"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               ENDPOINT STATUS TYPE
           -->
           <define name="endpoint-status-type">
            <choice>



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             <value>pending</value>
             <value>dialing-out</value>
             <value>dialing-in</value>
             <value>alerting</value>
             <value>on-hold</value>
             <value>connected</value>
             <value>muted-via-focus</value>
             <value>disconnecting</value>
             <value>disconnected</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               JOINING TYPE
           -->
           <define name="joining-type">
            <choice>
             <value>dialed-in</value>
             <value>dialed-out</value>
             <value>focus-owner</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               DISCONNECTION TYPE
           -->
           <define name="disconnection-type">
            <choice>
             <value>departed</value>
             <value>booted</value>
             <value>failed</value>
             <value>busy</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               EXECUTION TYPE
           -->
           <define name="execution-type">
            <interleave>
            <optional>
             <element name="when">
              <data type="dateTime"/>
             </element>
            </optional>
            <optional>
             <element name="reason">
              <text/>



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             </element>
            </optional>
            <optional>
             <element name="by">
              <data type="anyURI"/>
             </element>
            </optional>
            <ref name="anyAttribute"/>
            </interleave>
           </define>
           <!--
               CALL TYPE
           -->
           <define name="call-type">
            <interleave>
             <element name="sip">
              <ref name="sip-dialog-id-type"/>
             </element>
             <zeroOrMore>
              <ref name="anyElement"/>
             </zeroOrMore>
             <ref name="anyAttribute"/>
            </interleave>
           </define>
           <!--
               SIP DIALOG ID TYPE
           -->
           <define name="sip-dialog-id-type">
            <interleave>
            <optional>
            <element name="display-text">
             <text/>
            </element>
            </optional>
            <element name="call-id">
             <text/>
            </element>
            <element name="from-tag">
             <text/>
            </element>
            <element name="to-tag">
             <text/>
            </element>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            <ref name="anyAttribute"/>
            </interleave>



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           </define>
           <!--
               MEDIA TYPE
           -->
           <define name="media-type">
            <interleave>
            <attribute name="id">
             <data type="int"/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <element name="display-text">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="type">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="label">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="src-id">
              <text/>
             </element>
            </optional>
            <optional>
             <element name="status">
              <ref name="media-status-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:to-mixer">
              <ref name="mixer-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:from-mixer">
              <ref name="mixer-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>



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            </interleave>
           </define>
           <!--
               MEDIA STATUS TYPE
           -->
           <define name="media-status-type">
            <choice>
             <value>recvonly</value>
             <value>sendonly</value>
             <value>sendrecv</value>
             <value>inactive</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               SIDEBARS-BY-VAL TYPE
           -->
           <define name="sidebars-by-val-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="entry">
              <ref name="conference-type"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               CONFERENCE TIME
           -->
           <define name="conferencetime-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="xcon:entry">
              <element name="xcon:base">
               <text/>
              </element>
              <optional>
               <element name="xcon:mixing-start-offset">
                 <ref name="time-type"/>
                 <attribute name="required-participant">
                  <ref name="single-role-type"/>
                 </attribute>
                <ref name="anyAttribute"/>



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               </element>
              </optional>
              <optional>
               <element name="xcon:mixing-end-offset">
                <ref name="time-type"/>
                <attribute name="required-participant">
                 <ref name="single-role-type"/>
                </attribute>
                <ref name="anyAttribute"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:can-join-after-offset">
                <ref name="time-type"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:must-join-before-offset">
                <ref name="time-type"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:request-user">
                <ref name="time-type"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:notify-end-of-conference">
                <data type="int"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:allowed-extend-mixing-end-offset">
                <data type="boolean"/>
               </element>
              </optional>
              <zeroOrMore>
               <ref name="anyElement"/>
              </zeroOrMore>
             </element>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               TIME TYPE
           -->
           <define name="time-type">
             <data type="dateTime">



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               <param name="pattern">.+T.+Z.*</param>
             </data>
           </define>
           <!--
               SINGLE ROLE TYPE
           -->
           <define name="single-role-type">
            <choice>
             <value type="string">none</value>
             <value type="string">administrator</value>
             <value type="string">moderator</value>
             <value type="string">user</value>
             <value type="string">observer</value>
             <value type="string">participant</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               MIXING MODE TYPE
           -->
           <define name="mixing-mode-type">
            <choice>
             <value type="string">moderator-controlled</value>
             <value type="string">FCFS</value>
             <value type="string">automatic</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               CODECS TYPE
           -->
           <define name="codecs-type">
            <interleave>
            <attribute name="decision">
             <ref name="decision-type"/>
            </attribute>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="xcon:codec">
              <ref name="codec-type"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--



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               CODEC TYPE
           -->
           <define name="codec-type">
            <interleave>
            <attribute name="name">
             <text/>
            </attribute>
            <attribute name="policy">
             <ref name="policy-type"/>
            </attribute>
            <ref name="anyAttribute"/>
            <optional>
             <element name="xcon:subtype">
              <text/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               DECISION TYPE
           -->
           <define name="decision-type">
            <choice>
             <value type="string">automatic</value>
             <value type="string">moderator-controlled</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               POLICY TYPE
           -->
           <define name="policy-type">
            <choice>
             <value type="string">allowed</value>
             <value type="string">disallowed</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               CONTROL TYPE
           -->
           <define name="control-type">
            <interleave>
            <ref name="anyAttribute"/>
            <optional>



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             <element name="xcon:mute">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:pause-video">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:gain">
              <ref name="gain-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:video-layout">
              <ref name="video-layout-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               GAIN TYPE
           -->
           <define name="gain-type">
             <data type="int">
               <param name="minInclusive">-127</param>
               <param name="maxInclusive">127</param>
             </data>
           </define>
           <!--
               VIDEO LAYOUT TYPE
           -->
           <define name="video-layout-type">
              <choice>
               <value type="string">single-view</value>
               <value type="string">dual-view</value>
               <value type="string">dual-view-crop</value>
               <value type="string">dual-view-2x1</value>
               <value type="string">dual-view-2x1-crop</value>
               <value type="string">quad-view</value>
               <value type="string">multiple-3x3</value>
               <value type="string">multiple-4x4</value>
               <value type="string">multiple-5x1</value>
               <value type="string">automatic</value>



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               <ref name="free-text-extension"/>
              </choice>
           </define>
           <!--
               FLOOR INFORMATION TYPE
           -->
           <define name="floor-information-type">
            <interleave>
            <ref name="anyAttribute"/>
            <optional>
             <element name="xcon:conference-ID">
              <data type="unsignedLong"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:allow-floor-events">
              <data type="boolean"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:floor-request-handling">
              <ref name="floor-request-type"/>
             </element>
            </optional>
            <optional>
             <element name="xcon:conference-floor-policy">
              <ref name="conference-floor-policy"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               FLOOR REQUEST TYPE
           -->
           <define name="floor-request-type">
            <choice>
             <value type="string">block</value>
             <value type="string">confirm</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               CONFERENCE FLOOR POLICY
           -->
           <define name="conference-floor-policy">



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            <interleave>
            <ref name="anyAttribute"/>
            <oneOrMore>
             <element name="xcon:floor">
              <interleave>
              <attribute name="id">
               <text/>
              </attribute>
              <ref name="anyAttribute"/>
              <oneOrMore>
               <element name="xcon:media-label">
                <data type="nonNegativeInteger"/>
               </element>
              </oneOrMore>
              <optional>
               <element name="xcon:algorithm">
                <ref name="algorithm-type"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:max-floor-users">
                <data type="nonNegativeInteger"/>
               </element>
              </optional>
              <optional>
               <element name="xcon:moderator-id">
                <data type="nonNegativeInteger"/>
               </element>
              </optional>
              <zeroOrMore>
               <ref name="anyElement"/>
              </zeroOrMore>
              </interleave>
             </element>
            </oneOrMore>
            </interleave>
           </define>
           <!--
               ALGORITHM POLICY
           -->
           <define name="algorithm-type">
            <choice>
             <value type="string">moderator-controlled</value>
             <value type="string">FCFS</value>
             <value type="string">random</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>



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           <!--
               USERS ADMISSION POLICY
           -->
           <define name="user-admission-policy-type">
            <choice>
             <value type="string">closedAuthenticated</value>
             <value type="string">openAuthenticated</value>
             <value type="string">anonymous</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               JOIN HANDLING TYPE
           -->
           <define name="join-handling-type">
            <choice>
             <value type="string">block</value>
             <value type="string">confirm</value>
             <value type="string">allow</value>
             <value type="string">authenticate</value>
             <value type="string">directed-operator</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               DENY USERLIST
           -->
           <define name="deny-user-list-type">
            <interleave>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="xcon:target">
              <attribute name="uri">
               <data type="anyURI"/>
              </attribute>
              <ref name="anyAttribute"/>
             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               ALLOWED USERS LIST TYPE
           -->
           <define name="allowed-users-list-type">
            <interleave>



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            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="xcon:target">
              <ref name="target-type"/>
             </element>
            </zeroOrMore>
            <optional>
             <element name="xcon:persistent-list">
              <ref name="persistent-list-type"/>
             </element>
            </optional>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               PERSISTENT LIST TYPE
           -->
           <define name="persistent-list-type">
            <interleave>
              <zeroOrMore>
               <element name="xcon:user">
                <interleave>
                <attribute name="name">
                 <text/>
                </attribute>
                <attribute name="nickname">
                 <text/>
                </attribute>
                <attribute name="id">
                 <text/>
                </attribute>
                <ref name="anyAttribute"/>
                <zeroOrMore>
                 <element name="xcon:e-mail">
                  <text/>
                 </element>
                </zeroOrMore>
                <zeroOrMore>
                 <ref name="anyElement"/>
                </zeroOrMore>
                </interleave>
               </element>
             </zeroOrMore>
             <zeroOrMore>
              <ref name="anyElement"/>
             </zeroOrMore>



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            </interleave>
           </define>
           <!--
               TARGET TYPE
           -->
           <define name="target-type">
            <attribute name="uri">
             <data type="anyURI"/>
            </attribute>
            <attribute name="method">
             <ref name="method-type"/>
            </attribute>
            <ref name="anyAttribute"/>
           </define>
           <!--
               METHOD TYPE
           -->
           <define name="method-type">
            <choice>
             <value type="string">dial-in</value>
             <value type="string">dial-out</value>
             <value type="string">refer</value>
             <ref name="free-text-extension"/>
            </choice>
           </define>
           <!--
               ANONYMITY TYPE
           -->
           <define name="provide-anonymity-type">
              <choice>
               <value>private</value>
               <value>semi-private</value>
               <value>hidden</value>
               <ref name="free-text-extension"/>
              </choice>
           </define>
           <!--
               MIXER TYPE
           -->
           <define name="mixer-type">
            <interleave>
            <attribute name="name">
             <ref name="mixer-name-type"/>
            </attribute>
            <ref name="anyAttribute"/>
            <zeroOrMore>
             <element name="xcon:controls">
              <ref name="control-type"/>



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             </element>
            </zeroOrMore>
            <zeroOrMore>
             <ref name="anyElement"/>
            </zeroOrMore>
            </interleave>
           </define>
           <!--
               MIXER NAME TYPE
           -->
           <define name="mixer-name-type">
             <choice>
              <value>VideoIn</value>
              <value>VideoOut</value>
              <value>AudioOut</value>
              <value>AudioIn</value>
              <ref name="free-text-extension"/>
             </choice>
           </define>
           <!--
               FREE TEXT EXTENSION
               (re-define this as <notAllowed/>,
                if extensions beyond this spec are not used)
           -->
           <define name="free-text-extension">
            <text/>
           </define>

           <!--
            *********************************
            EXTENSIBILITY OF THE SCHEMA
            *********************************
           -->
           <!--
               EXTENSIBILITY ELEMENTS
               (re-define this as <empty/>,
                if extensions beyond this spec are not used)
           -->
           <define name="anyElement">
            <element>
             <anyName>
              <except>
               <name>conference-description</name>
               <name>host-info</name>
               <name>conference-state</name>
               <name>users</name>
               <name>sidebars-by-ref</name>
               <name>sidebars-by-val</name>



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               <name>display-text</name>
               <name>subject</name>
               <name>free-text</name>
               <name>keywords</name>
               <name>conf-uris</name>
               <name>service-uris</name>
               <name>maximum-user-count</name>
               <name>available-media</name>
               <name>web-page</name>
               <name>uris</name>
               <name>uri</name>
               <name>user-count</name>
               <name>active</name>
               <name>locked</name>
               <name>entry</name>
               <name>type</name>
               <name>status</name>
               <name>purpose</name>
               <name>modified</name>
               <name>user</name>
               <name>associated-aors</name>
               <name>roles</name>
               <name>languages</name>
               <name>cascaded-focus</name>
               <name>endpoint</name>
               <name>referred</name>
               <name>joining-method</name>
               <name>joining-info</name>
               <name>disconnection-method</name>
               <name>disconnection-info</name>
               <name>media</name>
               <name>call-info</name>
               <name>when</name>
               <name>reason</name>
               <name>by</name>
               <name>sip</name>
               <name>call-id</name>
               <name>from-tag</name>
               <name>to-tag</name>
               <name>label</name>
               <name>src-id</name>
               <name>xcon:conference-password</name>
               <name>xcon:mixing-mode</name>
               <name>xcon:codecs</name>
               <name>xcon:controls</name>
               <name>xcon:language</name>
               <name>xcon:allow-sidebars</name>
               <name>xcon:cloning-parent</name>



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               <name>xcon:sidebar-parent</name>
               <name>xcon:allow-conference-event-subscription</name>
               <name>xcon:to-mixer</name>
               <name>xcon:provide-anonymity</name>
               <name>xcon:allow-refer-users-dynamically</name>
               <name>xcon:allow-invite-users-dynamically</name>
               <name>xcon:allow-remove-users-dynamically</name>
               <name>xcon:from-mixer</name>
               <name>xcon:join-handling</name>
               <name>xcon:user-admission-policy</name>
               <name>xcon:allowed-users-list</name>
               <name>xcon:deny-users-list</name>
               <name>xcon:floor-information</name>
               <name>xcon:conference-time</name>
               <name>xcon:provide-anonymity</name>
               <name>xcon:floor</name>
               <name>xcon:entry</name>
               <name>xcon:mixing-start-offset</name>
               <name>xcon:mixing-end-offset</name>
               <name>xcon:can-join-after-offset</name>
               <name>xcon:must-join-before-offset</name>
               <name>xcon:request-user</name>
               <name>xcon:notify-end-of-conference</name>
               <name>xcon:allowed-extend-mixing-end-offset</name>
               <name>xcon:codec</name>
               <name>xcon:subtype</name>
               <name>xcon:mute</name>
               <name>xcon:pause-video</name>
               <name>xcon:gain</name>
               <name>xcon:video-layout</name>
               <name>xcon:conference-ID</name>
               <name>xcon:allow-floor-events</name>
               <name>xcon:floor-request-handling</name>
               <name>xcon:conference-floor-policy</name>
               <name>xcon:media-label</name>
               <name>xcon:algorithm</name>
               <name>xcon:max-floor-users</name>
               <name>xcon:moderator-id</name>
               <name>xcon:target</name>
               <name>xcon:persistent-list</name>
               <name>xcon:e-mail</name>
               <name>xcon:user</name>
              </except>
             </anyName>
             <ref name="anyExtension"/>
            </element>
           </define>




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           <define name="anyExtension">
            <zeroOrMore>
             <choice>
              <attribute>
               <anyName/>
              </attribute>
              <ref name="any"/>
             </choice>
            </zeroOrMore>
           </define>

           <define name="any">
            <element>
             <anyName/>
             <zeroOrMore>
              <choice>
               <attribute>
                <anyName/>
               </attribute>
               <text/>
               <ref name="any"/>
              </choice>
             </zeroOrMore>
           </element>
           </define>

           <!--
               EXTENSIBILITY ATTRIBUTES
               (re-define this as <empty/>,
                if extensions beyond this spec are not used)
           -->

           <define name="anyAttribute">
            <zeroOrMore>
             <attribute>
              <anyName>
               <except>
                <name ns="http://www.w3.org/XML/1998/namespace">lang
                </name>
                <name ns="">entity</name>
                <name ns="">required-participant</name>
                <name ns="">label</name>
                <name ns="">decision</name>
                <name ns="">name</name>
                <name ns="">policy</name>
                <name ns="">uri</name>
                <name ns="">method</name>
                <name ns="">id</name>



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                <name ns="">nickname</name>
               </except>
              </anyName>
             </attribute>
            </zeroOrMore>
           </define>
          </grammar>


Appendix B.  Non-Normative W3C XML Schema

   The non-normative W3C XML schema defines extension elements in the
   "urn:ietf:params:xml:ns:xcon-conference-info" namespace.  Note that
   <xs:any> extensions in this schema are stricter than in the normative
   RELAX NG schema [RELAX], and the normative RELAX NG schema [RELAX]
   allows unordered child elements unlike this schema (and the [RFC4575]
   schema).  Also note that this schema allows also otherwise valid
   extension elements to appear in the non-allowed positions.  Likewise
   the cardinalities of these extension elements can not be constrained
   with this schema.

<?xml version="1.0" encoding="UTF-8"?>
  <xs:schema
     xmlns="urn:ietf:params:xml:ns:xcon-conference-info"
     xmlns:info="urn:ietf:params:xml:ns:conference-info"
     xmlns:xs="http://www.w3.org/2001/XMLSchema"
     attributeFormDefault="unqualified" elementFormDefault="qualified"
     targetNamespace="urn:ietf:params:xml:ns:xcon-conference-info">

    <xs:import namespace="urn:ietf:params:xml:ns:conference-info"
      schemaLocation="rfc4575.xsd"/>

    <xs:import namespace="http://www.w3.org/XML/1998/namespace"
      schemaLocation="http://www.w3.org/2001/03/xml.xsd"/>

    <xs:element name="mixing-mode" type="mixing-mode-type"/>
    <xs:element name="codecs" type="codecs-type"/>
    <xs:element name="conference-password" type="xs:string"/>
    <xs:element name="controls" type="controls-type"/>
    <xs:element name="language" type="xs:language"/>
    <xs:element name="allow-sidebars" type="xs:boolean"/>
    <xs:element name="cloning-parent" type="xs:anyURI"/>
    <xs:element name="sidebar-parent" type="xs:anyURI"/>
    <xs:element name="conference-time" type="conference-time-type"/>
    <xs:element name="allow-conference-event-subscription"
      type="xs:boolean"/>
    <xs:element name="to-mixer" type="mixer-type"/>
    <xs:element name="provide-anonymity"



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      type="provide-anonymity-type"/>
    <xs:element name="allow-refer-users-dynamically"
      type="xs:boolean"/>
    <xs:element name="allow-invite-users-dynamically"
      type="xs:boolean"/>
    <xs:element name="allow-remove-users-dynamically"
      type="xs:boolean"/>
    <xs:element name="from-mixer" type="mixer-type"/>
    <xs:element name="join-handling" type="join-handling-type"/>
    <xs:element name="user-admission-policy"
      type="user-admission-policy-type"/>
    <xs:element name="allowed-users-list"
      type="allowed-users-list-type"/>
    <xs:element name="deny-users-list" type="deny-users-list-type"/>
    <xs:element name="floor-information" type="floor-information-type"/>

    <!-- CONFERENCE TIME -->

    <xs:complexType name="conference-time-type">
      <xs:sequence>
        <xs:element name="entry"
          minOccurs="0" maxOccurs="unbounded">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="base"
                type="xs:string" minOccurs="1"/>
              <xs:element name="mixing-start-offset" minOccurs="0">
                <xs:complexType>
                  <xs:simpleContent>
                    <xs:extension base="time-type">
                     <xs:attribute name="required-participant"
                       type="role-type" use="required"/>
                      <xs:anyAttribute namespace="##any"
                        processContents="lax"/>
                    </xs:extension>
                  </xs:simpleContent>
                </xs:complexType>
              </xs:element>
              <xs:element name="mixing-end-offset" minOccurs="0">
                <xs:complexType>
                  <xs:simpleContent>
                    <xs:extension base="time-type">
                      <xs:attribute name="required-participant"
                        type="role-type" use="required"/>
                      <xs:anyAttribute namespace="##any"
                        processContents="lax"/>
                    </xs:extension>
                  </xs:simpleContent>



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                </xs:complexType>
              </xs:element>
              <xs:element name="can-join-after-offset" type="time-type"
                minOccurs="0"/>
              <xs:element name="must-join-before-offset"
                type="time-type" minOccurs="0"/>
              <xs:element name="request-user" type="time-type"
                minOccurs="0"/>
              <xs:element name="notify-end-of-conference"
                type="xs:integer" minOccurs="0"/>
              <xs:element name="allowed-extend-mixing-end-offset"
                type="xs:boolean" minOccurs="0"/>
              <xs:any namespace="##other" processContents="lax"
                minOccurs="0" maxOccurs="unbounded"/>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- TIME TYPE -->

     <xs:simpleType name="time-type">
      <xs:restriction base="xs:dateTime">
        <xs:pattern value=".+T.+Z.*"/>
       </xs:restriction>
     </xs:simpleType>

    <!-- ROLE-TYPE -->

    <xs:simpleType name="role-type">
     <xs:restriction base="xs:string">
      <xs:pattern value="none"/>
      <xs:pattern value="administrator"/>
      <xs:pattern value="moderator"/>
      <xs:pattern value="user"/>
      <xs:pattern value="observer"/>
      <xs:pattern value="participant"/>
      <xs:pattern value=".+"/>
     </xs:restriction>
    </xs:simpleType>

    <!-- MIXING MODE TYPE -->

    <xs:simpleType name="mixing-mode-type">



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      <xs:restriction base="xs:string">
        <xs:pattern value="moderator-controlled"/>
        <xs:pattern value="FCFS"/>
        <xs:pattern value="automatic"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- CODECS TYPE -->

    <xs:complexType name="codecs-type">
      <xs:sequence>
        <xs:element name="codec" type="codec-type"/>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:attribute name="decision"
        type="decision-type" use="required"/>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- CODEC TYPE -->

    <xs:complexType name="codec-type">
      <xs:sequence>
        <xs:element name="subtype" type="xs:string" minOccurs="0"/>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:attribute name="name"
        type="xs:string" use="required"/>
      <xs:attribute name="policy"
        type="policy-type" use="required"/>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- DECISION TYPE -->

    <xs:simpleType name="decision-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="automatic"/>
        <xs:pattern value="moderator-controlled"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- POLICY TYPE -->




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     <xs:simpleType name="policy-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="allowed"/>
        <xs:pattern value="disallowed"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
     </xs:simpleType>

    <!-- CONTROL TYPE -->

    <xs:complexType name="controls-type">
      <xs:sequence>
        <xs:element name="mute"
          type="xs:boolean" minOccurs="0"/>
        <xs:element name="pause-video"
          type="xs:boolean" minOccurs="0"/>
        <xs:element name="gain"
          type="gain-type" minOccurs="0"/>
        <xs:element name="video-layout"
          type="video-layout-type" default="single-view" minOccurs="0"/>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- GAIN TYPE -->

    <xs:simpleType name="gain-type">
      <xs:restriction base="xs:integer">
        <xs:minInclusive value="-127"/>
        <xs:maxInclusive value="127"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- VIDEO LAYOUT TYPE -->

    <xs:simpleType name="video-layout-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="single-view"/>
        <xs:pattern value="dual-view"/>
        <xs:pattern value="dual-view-crop"/>
        <xs:pattern value="dual-view-2x1"/>
        <xs:pattern value="dual-view-2x1-crop"/>
        <xs:pattern value="quad-view"/>
        <xs:pattern value="multiple-3x3"/>
        <xs:pattern value="multiple-4x4"/>
        <xs:pattern value="multiple-5x1"/>



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        <xs:pattern value="automatic"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- FLOOR INFORMATION TYPE -->

    <xs:complexType name="floor-information-type">
      <xs:sequence>
        <xs:element name="conference-ID"
          type="xs:unsignedLong" minOccurs="0"/>
        <xs:element name="allow-floor-events"
          type="xs:boolean" default="false" minOccurs="0"/>
        <xs:element name="floor-request-handling"
          type="floor-request-handling-type" minOccurs="0"/>
        <xs:element name="conference-floor-policy"
          type="conference-floor-policy" minOccurs="0"/>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- FLOOR REQUEST TYPE -->

    <xs:simpleType name="floor-request-handling-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="block"/>
        <xs:pattern value="confirm"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- CONFERENCE FLOOR POLICY -->

    <xs:complexType name="conference-floor-policy">
      <xs:sequence>
        <xs:element name="floor" maxOccurs="unbounded">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="media-label"
                type="xs:string" minOccurs="1" maxOccurs="unbounded"/>
              <xs:element name="algorithm"
                type="algorithm-type" minOccurs="0"/>
              <xs:element name="max-floor-users"
                type="xs:nonNegativeInteger" minOccurs="0"/>
              <xs:element name="moderator-id"
                type="xs:nonNegativeInteger" minOccurs="0"/>



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                <xs:any namespace="##other" processContents="lax"
                  minOccurs="0" maxOccurs="unbounded"/>
            </xs:sequence>
            <xs:attribute name="id" type="xs:string" use="required"/>
            <xs:anyAttribute namespace="##any" processContents="lax"/>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- ALGORITHM TYPE -->

    <xs:simpleType name="algorithm-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="moderator-controlled"/>
        <xs:pattern value="FCFS"/>
        <xs:pattern value="random"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- USER ADMISSION POLICY TYPE -->

    <xs:simpleType name="user-admission-policy-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="closedAuthenticated"/>
        <xs:pattern value="openAuthenticated"/>
        <xs:pattern value="anonymous"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- JOIN HANDLING TYPE -->

    <xs:simpleType name="join-handling-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="block"/>
        <xs:pattern value="confirm"/>
        <xs:pattern value="allow"/>
        <xs:pattern value="authenticate"/>
        <xs:pattern value="directed-operator"/>
        <xs:pattern value=".+"/>
       </xs:restriction>
    </xs:simpleType>

   <!-- DENY USER LIST TYPE -->




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    <xs:complexType name="deny-users-list-type">
      <xs:sequence>
        <xs:element name="target" minOccurs="0" maxOccurs="unbounded">
          <xs:complexType>
            <xs:attribute name="uri" use="required" type="xs:anyURI"/>
            <xs:anyAttribute namespace="##any" processContents="lax"/>
          </xs:complexType>
        </xs:element>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

     <!-- ALLOWED USERS LIST TYPE -->

    <xs:complexType name="allowed-users-list-type">
      <xs:sequence>
        <xs:element name="target" type="target-type"
          minOccurs="0" maxOccurs="unbounded">
        </xs:element>
        <xs:element name="persistent-list"
          type="persistent-list-type"
          minOccurs="0"/>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- PERSISTENT LIST TYPE -->

    <xs:complexType name="persistent-list-type">
      <xs:sequence>
        <xs:element name="user" minOccurs="0" maxOccurs="unbounded">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="email" type="xs:string"
                minOccurs="0" maxOccurs="unbounded"/>
              <xs:any namespace="##other" processContents="lax"
                minOccurs="0" maxOccurs="unbounded"/>
            </xs:sequence>
            <xs:attribute name="name"
              use="required" type="xs:anyURI"/>
            <xs:attribute name="nickname"
              use="required" type="xs:string"/>
            <xs:attribute name="id"
              use="required" type="xs:string"/>



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            <xs:anyAttribute namespace="##any" processContents="lax"/>
          </xs:complexType>
        </xs:element>
        <xs:any namespace="##other" processContents="lax"
          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- TARGET TYPE -->

    <xs:complexType name="target-type">
      <xs:attribute name="uri" use="required"
        type="xs:anyURI"/>
      <xs:attribute name="method" use="required"
        type="method-type"/>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- METHOD TYPE -->

    <xs:simpleType name="method-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="dial-in"/>
        <xs:pattern value="dial-out"/>
        <xs:pattern value="refer"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- ANONYMITY TYPE -->

    <xs:simpleType name="provide-anonymity-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="private"/>
        <xs:pattern value="semi-private"/>
        <xs:pattern value="hidden"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

    <!-- MIXER TYPE -->

    <xs:complexType name="mixer-type">
      <xs:sequence>
        <xs:element name="controls" type="controls-type"
          minOccurs="0" maxOccurs="unbounded"/>
        <xs:any namespace="##other" processContents="lax"



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          minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:attribute name="name" type="mixer-name-type"
        use="required"/>
      <xs:anyAttribute namespace="##any" processContents="lax"/>
    </xs:complexType>

    <!-- MIXER NAME TYPE -->

    <xs:simpleType name="mixer-name-type">
      <xs:restriction base="xs:string">
        <xs:pattern value="VideoIn"/>
        <xs:pattern value="VideoOut"/>
        <xs:pattern value="AudioOut"/>
        <xs:pattern value="AudioIn"/>
        <xs:pattern value=".+"/>
      </xs:restriction>
    </xs:simpleType>

  </xs:schema>



Authors' Addresses

   Oscar Novo
   Ericsson
   Hirsalantie 11
   Jorvas  02420
   Finland

   Email: Oscar.Novo@ericsson.com


   Gonzalo Camarillo
   Ericsson
   Hirsalantie 11
   Jorvas  02420
   Finland

   Email: Gonzalo.Camarillo@ericsson.com










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   David P. Morgan
   Fidelity Investments
   82 Devonshire St, MZ V3C
   Boston, MA  02109-3614
   USA

   Email: Dave.Morgan@fmr.com


   Jari Urpalainen
   Nokia
   Itamerenkatu 11-13
   Helsinki  00180
   Finland

   Phone: +358 7180 37686
   Email: jari.urpalainen@nokia.com


































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