





Internet Engineering Task Force (IETF)                         M. Barnes
Request for Comments: 6504                                       Polycom
Category: Informational                                       L. Miniero
ISSN: 2070-1721                                                 Meetecho
                                                               R. Presta
                                                             S P. Romano
                                                    University of Napoli
                                                              March 2012


         Centralized Conferencing Manipulation Protocol (CCMP)
                           Call Flow Examples

Abstract

   This document provides detailed call flows for the scenarios
   documented in the Framework for Centralized Conferencing (XCON) (RFC
   5239) and in the XCON scenarios (RFC 4597).  The call flows document
   the use of the interface between a conference control client and a
   conference control server using the Centralized Conferencing
   Manipulation Protocol (CCMP) (RFC 6503).  The objective is to provide
   detailed examples for reference by both protocol researchers and
   developers.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Not all documents
   approved by the IESG are a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6504.

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.







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   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
   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.

Table of Contents

   1. Introduction ....................................................3
   2. Terminology .....................................................3
   3. Overview ........................................................4
   4. Working with CCMP ...............................................4
      4.1. CCMP and the Data Model ....................................5
      4.2. Using HTTP/TLS as a Transport ..............................6
      4.3. Conference Notifications ..................................10
   5. Conference Creation ............................................11
      5.1. Basic Conference Creation .................................12
      5.2. Conference Creation Using Blueprints ......................16
      5.3. Conference Creation Using User-Provided Conference
           Information ...............................................23
      5.4. Cloning an Existing Conference ............................28
   6. Conference Users Scenarios and Examples ........................31
      6.1. Adding a Party ............................................32
      6.2. Muting a Party ............................................35
      6.3. Conference Announcements and Recordings ...................38
      6.4. Monitoring for DTMF .......................................41
      6.5. Entering a Password-Protected Conference ..................42
   7. Sidebars Scenarios and Examples ................................44
      7.1. Internal Sidebar ..........................................45
      7.2. External Sidebar ..........................................54
      7.3. Private Messages ..........................................60
      7.4. Observing and Coaching ....................................64
   8. Removing Participants and Deleting Conferences .................71
      8.1. Removing a Party ..........................................71
      8.2. Deleting a Conference .....................................74
   9. Security Considerations ........................................75
   10. Acknowledgements ..............................................76
   11. References ....................................................76
      11.1. Normative References .....................................76
      11.2. Informative References ...................................76







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1.  Introduction

   This document provides detailed call flows for the scenarios
   documented in the Framework for Centralized Conferencing (XCON)
   [RFC5239] and in the XCON scenarios [RFC4597].  The XCON scenarios
   describe a broad range of use cases taking advantage of the advanced
   conferencing capabilities provided by a system realization of the
   XCON framework.  The call flows document the use of the interface
   between a conference control client and a conference control server
   using the Centralized Conferencing Manipulation Protocol (CCMP)
   [RFC6503].

   Due to the broad range of functionality provided by the XCON
   framework and the flexibility of the CCMP messaging, these call flows
   should not be considered inclusive of all the functionality that can
   provided by the XCON framework and protocol implementations.  These
   flows represent a sample to provide an overview of the feature-rich
   capabilities of the XCON framework and CCMP messaging for protocol
   developers, software developers, and researchers.

2.  Terminology

   This document uses the same terminology as found in the Architectural
   Framework for Media Server Control [RFC5567] and in the Media Control
   Channel Framework Call Flow Examples [CALL-FLOWS], with the following
   terms and abbreviations used in the call flows.  Also, note that the
   term "call flows" is used in a very generic sense in this document
   since the media is not limited to voice.  The calls supported by the
   XCON framework and CCMP can consist of media such as text, voice, and
   video, including multiple media types in a single active conference.

   Conference and Media Control Client (CMCC):  as defined in the XCON
      framework.  In the flows in this document, the CMCC is logically
      equivalent to the use of a User Agent Client (UAC) as the client
      notation in the media control call flows [CALL-FLOWS].  A CMCC
      differs from a generic media client in being an XCON-aware entity,
      thus, also being able to issue CCMP requests.

   Conference Server (ConfS):  In this document, the term "conference
      server" is used interchangeably with the term "Application Server
      (AS)" as used in the media control architectural framework
      [RFC5567].  A conference server is intended to be able to act as a
      conference control server, as defined in the XCON framework, i.e.,
      it is able to handle CCMP requests and issue CCMP responses.







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   Media Server (MS):  as defined in the media control architectural
      framework [RFC5567].

3.  Overview

   This document provides a sampling of detailed call flows that can be
   implemented based on a system realization of the XCON framework
   [RFC5239] and implementation of CCMP [RFC6503].  This is intended to
   be a simple guide for the use of the conference control protocol
   between the conference server and the conference control client.  The
   objective is to provide an informational base reference for protocol
   developers, software developers, and researchers.

   This document focuses on the interaction between the conference and
   media control client and the conferencing system, specifically the
   conference server.  The scenarios are based on those described in the
   XCON framework, many of which are based on the advanced conferencing
   capabilities described in the XCON scenarios.  Additional scenarios
   have been added to provide examples of other real-life scenarios that
   are anticipated to be supported by the framework.  With the exception
   of an initial example with media control messaging, the examples do
   not include the details for the media control [RFC6505], call
   signaling, or Binary Floor Control Protocols (BFCPs) [RFC4582].  This
   document references the scenarios in the media control call flows
   [CALL-FLOWS], SIP call control conferencing, [RFC4579], and BFCP
   documents.

   The rest of this document is organized as follows.  Section 4
   presents an overview on CCMP, together with some implementation-
   related details and related matters like HTTPS transport and
   notifications.  Section 5 presents the reader with examples showing
   the different approaches CCMP provides to create a new conference.
   Section 6 more generally addresses the different user-related
   manipulations that can be achieved by means of CCMP, by presenting a
   number of interesting scenarios.  Section 7 addresses several
   scenarios that may involve the use of sidebars.  Section 8 shows how
   CCMP can be used to remove conferences and users from the system.
   Finally, Section 9 provides a few details on the security
   considerations when it comes to implementing CCMP.

4.  Working with CCMP

   This section provides a brief introduction as to how the Centralized
   Conferencing Manipulation Protocol (CCMP) [RFC6503] works and how it
   can be transported across a network.  A typical CCMP interaction
   focusing on relevant aspects of the client-server communication is





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   described.  Please note that this section assumes the reader has read
   and understood the CCMP document.  This section is intended to help
   the reader understand the actual protocol interactions.

   First, a description of the protocol itself is provided Section 4.1,
   including some implementation considerations.  In Section 4.2, an
   effective CCMP interaction is presented by exploiting HTTPS as a
   transport.  Finally, notifications are described in Section 4.3.

   The document then presents and describes some actual flows in detail
   in the sections to follow.

4.1.  CCMP and the Data Model

   CCMP is an protocol based on XML [W3C.REC-xml-20081126].  It has been
   designed as a request/response protocol.  It is completely stateless,
   which means implementations can safely handle transactions
   independently from each other.

   The protocol allows for the manipulation of conference objects and
   related users.  This manipulation allows a conference and media
   control client (briefly CMCC in all the following sections) to
   create, update, and remove basically everything that is related to
   the objects handled by a conferencing system.  This is reflected in
   the allowed operations (retrieve, create, update, delete) and the
   specified request types (ranging from the manipulation of blueprints
   and conferences to users and sidebars).  For instance, CCMP provides
   ways to:

   o  retrieve the list of registered and/or active conferences in the
      system;

   o  create new conferences by exploiting several different approaches;

   o  add/remove users to/from a conference;

   o  update a conference with respect to all of its aspects;

   and so on.

   While CCMP acts as the means to manipulate conference objects, CCMP
   does not define these conference objects.  A separate document
   specifies how a conference object and all its components have to be
   constructed (Conference Information Data Model for Centralized
   Conferencing (XCON) [RFC6501]).  CCMP, depending upon the request
   type and the related operation, carries pieces of conference objects
   (or any object as a whole) according to the aforementioned




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   specification.  This means that any implementation aiming at being
   compliant with CCMP has to make sure that the transported objects are
   completely compliant with the data model specification and coherent
   with the constraints defined therein.  To make this clearer, there
   are elements that are mandatory in a conference object: issuing a
   syntactically correct CCMP request that carries a wrong conference
   object is doomed to result in a failure.  For this reason, it is
   suggested that the interested implementers take special care in
   carefully checking the data model handlers as well in order to avoid
   potential mistakes.

   However, there are cases when a mandatory element in the data model
   cannot be assigned in a conference object by a CCMP user.  For
   example, a CMCC may be requesting the direct creation of a new
   conference; in this case, a conference object assumes an 'entity'
   attribute uniquely identifying the conference to be in place.  Thus,
   the CMCC has no way to know a priori what the entity will be, since
   it is generated by the ConfS after the request.  For scenarios like
   this one, the CCMP specification describes the use of a dedicated
   placeholder wildcard (i.e., "AUTO_GENERATE_X", where X is an integer)
   to make the conference object compliant with the data model: the
   wildcard would then be replaced by the ConfS with the right value.

4.2.  Using HTTP/TLS as a Transport

   CCMP requires that implementations support HTTP/TLS as the transport
   mechanism.  Per CCMP, a CMCC sends a request as part of an HTTPS POST
   message, and the ConfS would reply with a 200 OK HTTPS response.  In
   both cases, the HTTPS messages carry the CCMP messages as payload,
   which is reflected in the Content-Type header
   ("application/ccmp+xml").  Figure 1 presents a ladder diagram of such
   an interaction, which is followed by a dump of the exchanged HTTPS
   messages for further analysis.  The examples in the remainder of this
   document show only the CCMP interactions.

















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    CMCC                                           ConfS
      |                                              |
      | 1. HTTPS POST (CCMP request)                 |
      |--------------------------------------------->|
      |                                              |
      |                                              |--+ Parse request,
      |                                              |  | update object
      |                                              |<-+ and reply
      |                                              |
      |                    2. 200 OK (CCMP response) |
      |<---------------------------------------------|
      |                                              |
      |--+ Parse response and                        |
      |  | update local copy                         |
      |<-+ of conference object                      |
      |                                              |
      '                                              '
      '                                              '

                          Figure 1: CCMP on HTTPS

   Per the protocol dump in the following lines, the CMCC has issued a
   CCMP request (a blueprintRequest message asking for a blueprint
   retrieval, i.e., with the <operation> element set to "retrieve" )
   towards the ConfS.  The request has been carried as payload of an
   HTTPS POST (message 1.) towards a previously known location.  The
   mandatory Host header has been specified, and the Content-Type header
   has been correctly set as well ("application/ccmp+xml").

   The ConfS, in turn, has handled the request and replied accordingly.
   The response (a blueprintResponse message with a <response-code> set
   to a successful value, "200") has been carried as payload of a 200 OK
   HTTPS response (message 2.).  As before, the Content-Type header has
   been correctly set ("application/ccmp+xml").

1. CMCC -> ConfS (HTTPS POST, CCMP request)
------------------------------------------
   POST /Xcon/Ccmp HTTP/1.1
   Content-Length: 657
   Content-Type: application/ccmp+xml
   Host: example.com:443
   Connection: Keep-Alive
   User-Agent: Apache-HttpClient/4.0.1 (java 1.5)








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   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpRequest
         xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                    xsi:type="ccmp:ccmp-blueprint-request-message-type">
           <confUserID>xcon-userid:Alice@example.com</confUserID>
           <confObjID>xcon:AudioRoom@example.com</confObjID>
           <operation>retrieve</operation>
           <ccmp:blueprintRequest/>
     </ccmpRequest>
   </ccmp:ccmpRequest>

2. CMCC <- ConfS (200 to POST, CCMP response)
---------------------------------------------
   HTTP/1.1 200 OK
   X-Powered-By: Servlet/2.5
   Server: Sun GlassFish Communications Server 1.5
   Content-Type: application/ccmp+xml;charset=ISO-8859-1
   Content-Length: 1652
   Date: Thu, 04 Feb 2010 14:47:56 GMT

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpResponse
         xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
         xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
     <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-blueprint-response-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <confObjID>xcon:AudioRoom@example.com</confObjID>
       <operation>retrieve</operation>
       <response-code>200</response-code>
       <response-string>success</response-string>
       <ccmp:blueprintResponse>
         <blueprintInfo entity="xcon:AudioRoom@example.com">
           <info:conference-description>
              <info:display-text>AudioRoom</info:display-text>
              <info:maximum-user-count>2</info:maximum-user-count>
              <info:available-media>
                <info:entry label="audioLabel">
                    <info:type>audio</info:type>
                </info:entry>
                </info:available-media>
           </info:conference-description>
           <info:users>
              <xcon:join-handling>allow</xcon:join-handling>



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           </info:users>
           <xcon:floor-information>
             <xcon:floor-request-handling>confirm
             </xcon:floor-request-handling>
             <xcon:conference-floor-policy>
                   <xcon:floor id="audioLabel"></xcon:floor>
             </xcon:conference-floor-policy>
           </xcon:floor-information>
         </blueprintInfo>
       </ccmp:blueprintResponse>
     </ccmpResponse>
   </ccmp:ccmpResponse>


   For completeness, the following provides some details of the CCMP
   interaction.  Despite the simplicity of the request, this flow
   provides some relevant information on how CCMP messages are built.
   Specifically, both the CCMP request and the CCMP response share a
   subset of the message:

   o  <confUserID>: this element, provided by the CMCC, refers to the
      requester by means of his XCON-USERID; except in a few scenarios
      (presented in the following sections), this element must always
      contain a valid value;

   o  <confObjID>: this element refers to the target conference object,
      according to the request in place;

   o  <operation>: this element specifies the operation the CMCC wants
      to perform, according to the specific request type.

   Besides those elements, the CMCC (let's say Alice, whose XCON-USERID
   is "xcon-userid:Alice@example.com") has also provided an additional
   element, <blueprintRequest>.  The name of that element varies
   according to the request type in which the CMCC is interested.  In
   this specific scenario, the CMCC was interested in acquiring details
   concerning a specific blueprint (identified by its XCON-URI
   "xcon:AudioRoom@example.com", as reflected in the provided
   <confObjID> target element), and so the request consisted in an empty
   <blueprintRequest> element.  It will be clearer in the following
   sections that different request types may require different elements
   and, as a consequence, different content.

   Considering the request was a blueprintRequest message, the ConfS has
   replied with a blueprintResponse message containing a
   <blueprintResponse> element.  This element includes a complete dump
   of the conference object (compliant with the data model) describing
   the requested blueprint.



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   Without providing additional details of this interaction, it is worth
   noting that this was the example of the simplest CCMP communication
   that could take place between a CMCC and a ConfS, a blueprint
   request: this scenario will be described in more detail in
   Section 5.2.

4.3.  Conference Notifications

   The XCON framework [RFC5239] identifies several different possible
   protocol interactions between a conference server and a conferencing
   client.  One of those interactions is generically called
   "notification protocol" providing a mechanism for all clients
   interested in being informed by the server whenever something
   relevant happens in a conference.  When SIP is used as the call
   signaling protocol in a CCMP implementation, the XCON event package
   [RFC6502], which extends the SIP event package for conference state
   [RFC4575] must be supported.  A SIP client uses the SIP SUBSCRIBE
   message for the XCON event package to subscribe to notifications
   related to a specific conference.  A SIP client would receive
   notifications describing all the changes to the document via a SIP
   NOTIFY message.  An example ladder diagram is presented in Figure 2;
   in this figure, we assume a CMCC has updated a conference object, and
   a previously subscribed SIP client is notified of the update.




























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       CMCC                   ConfS                        UAC
        |                       |                           |
        |                       |          1. SIP SUBSCRIBE |
        |                       |<--------------------------|
        |             Handle +--|                           |
        |                new |  |                           |
        |       subscription +->| 2. SIP 200 OK             |
        |                       |-------------------------->|
        |                       |                           |
        '                       '                           '
        '                       '                           '
        |                       |                           |
        | 3. CCMP (add user)    |                           |
        |---------------------->|                           |
        |                       |--+ Add user               |
        |                       |  | to conf.               |
        |                       |<-+ object                 |
        |     4. CCMP (success) |                           |
        |<----------------------|                           |
        |                       | 5. SIP NOTIFY (changes)   |
        |                       |-------------------------->|
        |                       |             6. SIP 200 OK |
        |                       |<--------------------------|
        |                       |                           |
        '                       '                           '
        '                       '                           '

              Figure 2: XCON Event Package: SIP Notifications

   The detailed flows in this document generically present a
   notification, when appropriate, but do not include the SIP messaging
   details.

5.  Conference Creation

   This section provides details associated with the various ways in
   which a conference can be created using CCMP and the XCON framework
   constructs.  As previously mentioned, the details of the media
   control, call signaling, and floor control protocols, where
   applicable, are annotated in the flows without showing all the
   details.  This also applies to CCMP, whose flows are related to the
   protocol alone, hiding any detail concerning the transport that may
   have been used (e.g., HTTPS).  However, for clarification purposes,
   the first example in Section 5.1 provides the details of the media
   control messaging with the standard annotation used throughout the
   remainder of this document.  In subsequent flows, only this





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   annotation (identified by lowercase letters) is included, and the
   reader is encouraged to refer to the call flows in the relevant
   documents for details about the other protocols.  The annotations for
   the call signaling are on the left side of the conference server
   vertical bar, and those for the media control messaging are on the
   right side.

5.1.  Basic Conference Creation

   The simplest manner in which a conference can be created is
   accomplished by the client sending a confRequest message with the
   <operation> element set to "create" as the only parameter to the
   conference server, together with the <confUserID> associated with the
   requesting client itself.  This results in the creation of a default
   conference, with an XCON-URI in the form of the <confObjID> element,
   the XCON-USERID in the form of the <confUserID> element (the same one
   already present in the request), and the data for the conference
   object in the <confInfo> parameter all returned in the confResponse
   message.  This example also adds the issuing user to the conference
   upon creation with the 'method' attribute in the <target> child
   element of <allowed-users-list> set to "dial-out".

   The specific data for the conference object is returned in the
   confResponse message in the <confInfo> parameter.  This allows the
   client (with the appropriate authorization) to manipulate these data
   and add additional participants to the conference, as well as change
   the data during the conference.  In addition, the client may
   distribute the conferencing information to other participants
   allowing them to join, the details of which are provided in
   additional flows.  Please notice that, according to the CCMP
   specification, the return of the new conference data in the
   <confInfo> element is not mandatory: if the <confInfo> parameter of
   is not included in the successful confResponse/create message, a
   subsequent confRequest/retrieve message of the returned <confObjID>
   can be triggered to provide the requesting client with the detailed
   conference description.

   Clients that are not XCON-aware can join the conference using a
   specific signaling interface such as SIP [RFC3261] (using the
   signaling interface to the conference focus as described in
   [RFC4579]), or other supported signaling protocols, being XCON-
   agnostic with respect to them.  However, these details are not shown
   in the message flows.  The message flows in this document identify
   the point in the message flows at which this signaling occurs via the
   lowercase letter items (i.e., (a)...(x)) along with the appropriate
   text for the processing done by the conference server.





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   As previously described, this example also shows how the conferencing
   system may make use of other standard protocol components for
   complete functionality.  An example of that is the media control
   framework [RFC5567], which allows the conferencing system to
   configure conference mixes, Interactive Voice Response (IVR) dialogs,
   and all sorts of media-related interactions an application like this
   may need.  In order to provide the reader with some insight on these
   interactions, the conference server in this example also configures
   and starts a mixer via a media control channel as soon as the
   conference is created (transactions A1 and A2), and attaches clients
   to it when necessary (e.g., when CMCC1 joins the conference by means
   of SIP signaling, its media channels are attached to the media server
   (MS) in B1/B2).  Note, that the media control interfaces are NOT
   shown in the remaining call flows in this document but rather follow
   the same annotation as with the SIP signaling such that (b)
   correlates with the A1 and A2 transactions and (d) correlates with
   the B1 and B2 transactions.


































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   CMCC1          CMCC2        CMCCx       ConfS          MS
     |               |           |           |             |
     |(1)confRequest(confUserID, create)     |             |
     |-------------------------------------->|             |
     |               |         (a)Create +---|             |
     |               |           |Conf   |   |             |
     |               |           |Object |   |             |
     |               |           |& IDs  +-->|             |
     |               |           |           | A1. CONTROL |
     |               |           |           |+++++++++++>>|
     |               |           |           |(create conf)|--+ (b)
     |               |           |           |             |  | create
     |               |           |           |             |  | conf and
     |               |           |           | A2. 200 OK  |<-+ its ID
     |               |           |           |<<+++++++++++|
     |               |           |           |(confid=Y)   |
     |(2)confResponse(confUserID,confObjID,  |             |
     |                create, 200, success,  |             |
     |                version, confInfo)     |             |
     |<--------------------------------------|             |
     |               |           |           |             |
     |               |     (c) Focus     +---|             |
     |               |         sets up   |   |             |
     |               |         signaling |   |             |
     |               |         to CMCC1  +-->|             |
     |               |           |           |             |
     |               |           |           | B1. CONTROL |
     |               |           |           |+++++++++++>>|
     |               |           |           | (join CMCC1 |
     |               |           |           | <->confY)   |
     |               |           |           |             |
     |               |           |           |             |--+(d) join
     |               |           |           |             |  | CMCC1 &
     |               |           |           | B2.200 OK   |<-+ conf Y
     |               |           |           |<<+++++++++++|
     |               |           |           |             |
     |<<#################################################>>|
     |        Now the CMCC1 is mixed in the conference     |
     |<<#################################################>>|
     |               |           |           |             |
     |******CMCC1 may then manipulate conference data *****|
     |****** and add addt'l users, etc.      |        *****|
     '               '           '           '             '
     '               '           '           '             '
     '               '           '           '             '

             Figure 3: Create Basic Conference - Complete flow




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1. confRequest/create message (Alice creates a default conference)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:type="ccmp:ccmp-conf-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <operation>create</operation>
        <ccmp:confRequest/>
     </ccmpRequest>
  </ccmp:ccmpRequest>

2. confResponse/create message ("success", created conference
   object returned)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
     <ccmp:ccmpResponse
          xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
          xmlns:info="urn:ietf:params:xml:ns:conference-info"
          xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
         <ccmpResponse
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:type="ccmp:ccmp-conf-response-message-type">
          <confUserID>xcon-userid:Alice@example.com</confUserID>
          <confObjID>xcon:8977794@example.com</confObjID>
          <operation>create</operation>
          <response-code>200</response-code>
          <response-string>success</response-string>
          <version>1</version>
          <ccmp:confResponse>
              <confInfo entity="xcon:8977794@example.com">
                 <info:conference-description>
                     <info:display-text>
                        Default conference initiated by Alice
                     </info:display-text>
                     <info:conf-uris>
                        <info:entry>
                           <info:uri>
                               xcon:8977794@example.com
                           </info:uri>
                           <info:display-text>
                               Conference XCON-URI
                           </info:display-text>




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                           </info:entry>
                      </info:conf-uris>
                      <info:maximum-user-count>10
                      </info:maximum-user-count>
                      <info:available-media>
                             <info:entry label="11">
                                 <info:type>audio</info:type>
                             </info:entry>
                      </info:available-media>
                      </info:conference-description>
                       <info:conference-state>
                         <info:active>false</info:active>
                       </info:conference-state>
                  <info:users>
                     <xcon:join-handling>allow</xcon:join-handling>
                     <xcon:allowed-users-list>
                        <xcon:target uri="xcon-userid:Alice@example.com"
                                     method="dial-out"/>
                      </xcon:allowed-users-list>
                  </info:users>
              </confInfo>
          </ccmp:confResponse>
        </ccmpResponse>
     </ccmp:ccmpResponse>

           Figure 4: Create Basic Conference Detailed Messaging

5.2.  Conference Creation Using Blueprints

   The previous example showed the creation of a new conference using
   default values.  This means the client provided no information about
   how she wanted the conference to be created.  The XCON framework (and
   CCMP as a consequence) allows for the implementation of templates.
   These templates are called "conference blueprints" and are basically
   conference objects with predefined settings.  This means that a
   client might get a list of blueprints, choose the one that most fits
   his needs, and use the chosen blueprint to create a new conference.

   Figure 5 provides an example of one client, Alice, discovering the
   conference blueprints available for a particular conferencing system
   and creating a conference based on the desired blueprint.  In
   particular, Alice is interested in those blueprints suitable to
   represent a video conference, i.e., a conference in which both audio
   and video are available, so she makes use of the filter mechanism
   provided by CCMP to make a selective blueprints retrieve request.
   This results in three distinct CCMP transactions.





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   CMCC Alice                   ConfS
    |                               |
    | (1) blueprintsRequest         |
    |    (confUserID,xpathFilter)   |
    |------------------------------>|
    |                               |
    |        (2) blueprintsResponse |
    |           (confUserID,        |
    |            200, success,      |
    |            blueprintsInfo)    |
    |                               |
    |<------------------------------|
    |                               |
    |--+                            |
    |  | choose preferred           |
    |  | blueprint from the         |
    |  | list (blueprintName)       |
    |<-+                            |
    |                               |
    | (3) blueprintRequest          |
    | (confUserID,confObjID,        |
    |  retrieve)                    |
    |------------------------------>|
    |                               |
    |      4) blueprintResponse     |
    |         (confUserID,confObjID,|
    |          retrieve, 200,       |
    |          success, confInfo)   |
    |<------------------------------|
    |                               |
    | (5) confRequest(confUserID,   |
    |     confObjID,create)         |
    |------------------------------>|
    |                               |
    |                 (a)Create +---|
    |                    Conf   |   |
    |                    Object |   |
    |                    & IDs  +-->|
    |                               |--+ (b) MS
    |                               |  | creates
    |                               |  | conf and
    |                               |<-+ its ID
    |                               |   (confid=Y)
    |(6) confResponse               |
    | (confUserID, confObjID*,      |
    |  create, 200, success)        |
    |<------------------------------|
    |                               |



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    |                               |
    |                               |
    '                               '
    '                               '

         Figure 5: Client Creation of Conference Using Blueprints

   1.  Alice first sends a blueprintsRequest message to the conference
       server identified by the conference server discovery process.
       This request contains the <confUserID> set to the XCON-USERID of
       the user issuing the request (in this case, the one belonging to
       Alice) and the <xpathFilter> element by which Alice specifies she
       desires to obtain only blueprints providing support for both
       audio and video: for this purpose, the xpath query contained in
       this field is: "/conference-info[conference-description/
       available-media/entry/type='audio' and conference-description/
       available-media/entry/type='video']".  Upon receipt of the
       blueprintsRequest message, the conference server would first
       ensure, on the basis of the <confUserID> parameter, that Alice
       has the appropriate authority based on system policies to receive
       the requested kind of blueprints supported by that system.

   2.  All blueprints that Alice is authorized to use are returned in a
       blueprintsResponse message in the <blueprintsInfo> element.

   3.  Upon receipt of the blueprintsResponse message containing the
       blueprints, Alice determines which blueprint to use for the
       conference to be created.  Alice sends a blueprintRequest message
       to get the specific blueprint as identified by the <confObjID>.

   4.  The conference server returns the details associated with the
       specific blueprint identified by the <confObjID> in the
       <confInfo> element within the blueprintResponse message.

   5.  Alice finally sends a confRequest message with a "create"
       <operation> to the conference server to create a conference
       reservation cloning the chosen blueprint.  This is achieved by
       writing the blueprint's XCON-URI in the <confObjID> parameter.

   6.  Upon receipt of the confRequest/create message, the conference
       server uses the received blueprint to clone a conference,
       allocating a new XCON-URI (called "confObjID*" in the example).
       The conference server then sends a confResponse message including
       the new "confObjID*" associated with the newly created conference
       instance as the value of the <confObjID> parameter.  Upon receipt
       of the confResponse message, Alice can now add other users to the
       conference.




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 1. blueprintsRequest message (Alice requires the list of the
    available blueprints with video support)

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
     xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
     xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="ccmp:ccmp-blueprints-request-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <ccmp:blueprintsRequest>
         <xpathFilter>/conference-info[conference-description/
            available-media/entry/type='audio'
            and
            conference-description/available-media/entry/type='video']
         </xpathFilter>
       </ccmp:blueprintsRequest>
    </ccmpRequest>
   </ccmp:ccmpRequest>

2. blueprintsResponse message (the server provides a
   descriptions of the available blueprints
   fitting Alice's request)

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpResponse
    xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
    xmlns:info="urn:ietf:params:xml:ns:conference-info"
    xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
   <ccmpResponse
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:type="ccmp:ccmp-blueprints-response-message-type">
      <confUserID>xcon-userid:Alice@example.com</confUserID>
      <response-code>200</response-code>
      <response-string>success</response-string>
        <ccmp:blueprintsResponse>
         <blueprintsInfo>
          <info:entry>
           <info:uri>xcon:VideoRoom@example.com</info:uri>
           <info:display-text>VideoRoom</info:display-text>
           <info:purpose>Video Room:
               conference room with public access,
               where both audio and video are available,
               4 users can talk and be seen at the same time,
               and the floor requests are automatically accepted.
           </info:purpose>
          </info:entry>
          <info:entry>



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           <info:uri>xcon:VideoConference1@example.com</info:uri>
           <info:display-text>VideoConference1</info:display-text>
             <info:purpose>Public Video Conference: conference
                 where both audio and video are available,
                 only one user can talk
             </info:purpose>
           </info:entry>
        </blueprintsInfo>
      </ccmp:blueprintsResponse>
     </ccmpResponse>
   </ccmp:ccmpResponse>

3. blueprintRequest/retrieve message (Alice wants the
   "VideoRoom" blueprint)

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpRequest
         xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                    xsi:type="ccmp:ccmp-blueprint-request-message-type">
           <confUserID>xcon-userid:Alice@example.com</confUserID>
           <confObjID>xcon:VideoRoom@example.com</confObjID>
           <operation>retrieve</operation>
           <ccmp:blueprintRequest/>
     </ccmpRequest>
   </ccmp:ccmpRequest>

4. blueprintResponse/retrieve message ("VideoRoom"
   conference object returned)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <ccmp:ccmpResponse
         xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
         xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
     <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-blueprint-response-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <confObjID>xcon:VideoRoom@example.com</confObjID>
       <operation>retrieve</operation>
       <response-code>200</response-code>
       <response-string>success</response-string>
       <ccmp:blueprintResponse>
         <blueprintInfo entity="xcon:VideoRoom@example.com">
           <info:conference-description>
              <info:display-text>VideoRoom</info:display-text>



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              <info:maximum-user-count>4</info:maximum-user-count>
              <info:available-media>
                <info:entry label="audioLabel">
                    <info:type>audio</info:type>
                </info:entry>
                <info:entry label="videoLabel">
                    <info:type>video</info:type>
                </info:entry>
                </info:available-media>
           </info:conference-description>
           <info:users>
              <xcon:join-handling>allow</xcon:join-handling>
           </info:users>
           <xcon:floor-information>
             <xcon:floor-request-handling>confirm
             </xcon:floor-request-handling>
             <xcon:conference-floor-policy>
                   <xcon:floor id="audioFloor">
                    <xcon:media-label>audioLabel</xcon:media-label>
                   </xcon:floor>
                   <xcon:floor id="videoFloor">
                        <xcon:media-label>videoLabel</xcon:media-label>
                   </xcon:floor>
             </xcon:conference-floor-policy>
           </xcon:floor-information>
         </blueprintInfo>
       </ccmp:blueprintResponse>
     </ccmpResponse>
   </ccmp:ccmpResponse>

5. confRequest/create message (Alice clones the "VideoRoom" blueprint)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:type="ccmp:ccmp-conf-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:VideoRoom@example.com</confObjID>
        <operation>create</operation>
        <ccmp:confRequest/>
     </ccmpRequest>
  </ccmp:ccmpRequest>





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6. confResponse/create message (cloned conference
   object returned)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
       xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
       xmlns:info="urn:ietf:params:xml:ns:conference-info"
       xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="ccmp:ccmp-conf-response-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <confObjID>xcon:8977794@example.com</confObjID>
       <operation>create</operation>
       <response-code>200</response-code>
       <response-string>success</response-string>
       <version>1</version>
       <ccmp:confResponse>
            <confInfo entity="xcon:8977794@example.com">
              <info:conference-description>
                  <info:display-text>
                     New conference by Alice cloned from VideoRoom
                  </info:display-text>
                  <info:conf-uris>
                     <info:entry>
                        <info:uri>
                            xcon:8977794@example.com
                        </info:uri>
                        <info:display-text>
                            conference xcon-uri
                        </info:display-text>
                        <xcon:conference-password>
                            8601
                        </xcon:conference-password>
                      </info:entry>
                   </info:conf-uris>
                   <info:maximum-user-count>10</info:maximum-user-count>
                   <info:available-media>
                          <info:entry label="11">
                              <info:type>audio</info:type>
                          </info:entry>
                          <info:entry label="12">
                              <info:type>video</info:type>
                          </info:entry>
                   </info:available-media>
               </info:conference-description>
               <info:users>
                   <xcon:join-handling>allow</xcon:join-handling>



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               </info:users>
                  <xcon:floor-information>
                     <xcon:floor-request-handling>
                        confirm</xcon:floor-request-handling>
                     <xcon:conference-floor-policy>
                       <xcon:floor id="1">
                       <xcon:media-label>11</xcon:media-label>
                       </xcon:floor>
                       <xcon:floor id="2">
                       <xcon:media-label>12</xcon:media-label>
                       </xcon:floor>
                     </xcon:conference-floor-policy>
                  </xcon:floor-information>
              </confInfo>
          </ccmp:confResponse>
      </ccmpResponse>
  </ccmp:ccmpResponse>

        Figure 6: Create Conference (Blueprint) Detailed Messaging

5.3.  Conference Creation Using User-Provided Conference Information

   A conference can also be created by the client sending a confRequest
   message with the "create" <operation>, along with the desired data in
   the form of the <confInfo> element for the conference to be created.
   The request also includes the <confUserID> set to the XCON-USERID of
   the requesting entity.

   This approach allows for a client (in this example Alice) to
   completely describe what the conference object should look like,
   without relying on defaults or blueprints; for example, which media
   should be available, the topic, the users allowed to join, any
   scheduling-related information, and so on.  This can be done by
   providing, in the creation request, a full conference object for the
   server to parse.

   This <confInfo> parameter must comply with the data model
   specification.  This means that the 'entity' attribute is mandatory
   and cannot be missing in the document.  However, in this example, the
   client is actually requesting the creation of a new conference, which
   doesn't exist yet, so the 'entity' attribute is unknown.  As
   discussed in Section 4.1, CCMP allows for the use of a wildcard
   placeholder.  This placeholder ("xcon:AUTO_GENERATE_1@example.com" in
   the example) is only to ensure the <confInfo> element is compliant
   with the data model and would subsequently be replaced by the
   conference server with the actual value.  Thus, when the conference
   server actually creates the conference, a valid value for the
   'entity' attribute is created for it as well, which takes the place



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   of the wildcard value when the actual conference object provided by
   the client is populated.

   To give a flavor of what could be added to the conference object, we
   assume Alice is also interested in providing scheduling-related
   information.  So, in this example, Alice also specifies by the
   <conference-time> element included in the <confInfo> that the
   conference she wants to create has to occur on a certain date
   spanning from a certain start time to a certain stop time and has to
   be replicated weekly.

   Moreover, Alice indicates by means of the <allowed-users-list>
   element that at the start time Bob, Carol, and herself have to be
   called by the conferencing system to join the conference (in fact,
   for each <target> field corresponding to one of the aforementioned
   clients, the 'method' attribute is set to "dial-out").

   Once Alice has prepared the <confInfo> element and sent it as part of
   her request to the server, if the conferencing system can support
   that specific type of conference (capabilities, etc.), then the
   request results in the creation of a conference.  We assume the
   request has been successful, and as a consequence, the XCON-URI in
   the form of the <confObjID> parameter and the XCON-USERID in the form
   of the <confUserID> parameter (again, the same as the requesting
   entity) are returned in the confResponse message.

   In this example, the created conference object is not returned in the
   successful confResponse message in the <confInfo> parameter.
   Nevertheless, Alice could still retrieve the actual conference object
   by issuing a confRequest message with a "retrieve" <operation> on the
   XCON-URI returned in the <confObjID> of the previous response.  Such
   a request would show how, as described at the beginning of this
   section, the 'entity' attribute of the conference object in the
   <confInfo> field is replaced with the actual information (i.e.,
   "xcon:6845432@example.com").
















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   Alice            Bob        Carol       ConfS
     |               |           |           |
     |               |           |           |
     |(1)confRequest(confUserID, |           |
     |         create, confInfo) |           |
     |               |           |           |
     |-------------------------------------->|
     |               |           |           |
     |               |         (a)Create +---|
     |               |           |Conf   |   |
     |               |           |Object |   |
     |               |           |& IDs  +-->|
     |               |           |           |--+ (b) MS
     |               |           |           |  | creates
     |               |           |           |  | conf and
     |               |           |           |<-+ its ID
     |               |           |           |   (confid=Y)
     |(2)confResponse(confUserID,|           |
     |       confObjID, create,  |           |
     |       200, success, version)          |
     |<--------------------------------------|
     |               |           |           |
    ===========================================
    ...             ...         ...         ...
    ========== START TIME OCCURS ==============
     |               |     (c) Focus     +---|
     |               |         sets up   |   |
     |               |         signaling |   |
     |               |         to Alice  +-->|
     |               |           |           |
     |               |           |           |--+(d) MS joins
     |               |           |           |  | Alice &
     |               |           |           |<-+ conf Y
     |               |           |           |
     |               |           |           |
     |<<###################################>>|
     | Alice is mixed in the conference      |
     |<<###################################>>|
     |               |           |           |
     |               |     (e)Focus      +---|
     |               |        sets up    |   |
     |               |        signaling  |   |
     |               |        to Bob     |   |
     |               |           |       +-->|
     |               |           |           |
     |               |           |           |--+(f)MS joins
     |               |           |           |  | Bob &
     |               |           |           |<-+ conf Y



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     |               |           |           |
     |               |<<###################>>|
     |               |  Bob is mixed too     |
     |               |<<###################>>|
     |               |           |           |
     |               |     (g )Focus     +---|
     |               |         sets up   |   |
     |               |         signaling |   |
     |               |         to Carol  |   |
     |               |         CMCCx     +-->|
     |               |           |           |
     |               |           |           |--+(h)MS joins
     |               |           |           |  | CMCCx &
     |               |           |           |<-+ conf Y
     |               |           |           |
     |               |           |<<#######>>|
     |               |           |Carol mixed|
     |               |           |<<#######>>|
     |               |           |           |
     |               |           |           |
     |               |           |           |
     |<***All parties connected to conf Y***>|
     |               |           |           |
     |               |           |           |
     '               '           '           '
     '               '           '           '
     '               '           '           '

   Figure 7: Create Basic Conference from User-Provided Conference Info

  1. confRequest/create message (Alice proposes a conference object
     to be created)

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:type="ccmp:ccmp-conf-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <operation>create</operation>
        <ccmp:confRequest>
           <confInfo entity="xcon:AUTO_GENERATE_1@example.com">
              <info:conference-description>
                  <info:display-text>
                     Dial-out conference initiated by Alice



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                  </info:display-text>
                   <info:maximum-user-count>10</info:maximum-user-count>
                   <info:available-media>
                          <info:entry label="AUTO_GENERATE_2">
                              <info:type>audio</info:type>
                          </info:entry>
                   </info:available-media>
                   <xcon:conference-time>
                    <xcon:entry>
                     <xcon:base>
                       BEGIN:VCALENDAR
                       VERSION:2.0
                       PRODID:-//Mozilla.org/NONSGML
                                 Mozilla Calendar V1.0//EN
                       BEGIN:VEVENT
                       DTSTAMP: 20100127T140728Z
                       UID: 20100127T140728Z-345FDA-alice@example.com
                       ORGANIZER:MAILTO:alice@example.com
                       DTSTART:20100127T143000Z
                       RRULE:FREQ=WEEKLY
                       DTEND: 20100127T163000Z
                       END:VEVENT
                       END:VCALENDAR
                     </xcon:base>
                     <xcon:mixing-start-offset
                      required-participant="moderator">
                          2010-01-27T14:29:00Z
                     </xcon:mixing-start-offset>
                     <xcon:mixing-end-offset
                      required-participant="participant">
                          2010-01-27T16:31:00Z
                     </xcon:mixing-end-offset>
                     <xcon:must-join-before-offset>
                          2010-01-27T15:30:00Z
                     </xcon:must-join-before-offset>
                    </xcon:entry>
                   </xcon:conference-time>
               </info:conference-description>
               <info:users>
                  <xcon:join-handling>allow</xcon:join-handling>
                  <xcon:allowed-users-list>
                     <xcon:target uri="xcon-userid:alice@example.com"
                                   method="dial-out"/>
                     <xcon:target uri="sip:bob83@example.com"
                                   method="dial-out"/>
                     <xcon:target uri="sip:carol@example.com"
                                   method="dial-out"/>
                   </xcon:allowed-users-list>



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               </info:users>
           </confInfo>
        </ccmp:confRequest>
     </ccmpRequest>
  </ccmp:ccmpRequest>

  2. confResponse/create message ("200", "success")

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
       xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
       xmlns:info="urn:ietf:params:xml:ns:conference-info"
       xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
      <ccmpResponse
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="ccmp:ccmp-conf-response-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <confObjID>xcon:6845432@example.com</confObjID>
       <operation>create</operation>
       <response-code>200</response-code>
       <response-string>success</response-string>
       <version>1</version>
       <ccmp:confResponse/>
      </ccmpResponse>
  </ccmp:ccmpResponse>

           Figure 8: Create Basic Conference Detailed Messaging

5.4.  Cloning an Existing Conference

   A client can also create another conference by cloning an existing
   conference, such as an active conference or conference reservation.
   This approach can be seen as a logical extension of the creation of a
   new conference using a blueprint: the difference is that, instead of
   cloning the predefined settings listed in a blueprint, the settings
   of an existing conference would be cloned.

   In this example, the client sends a confRequest message with the
   "create" <operation>, along with her XCON-USERID in the <confUserID>
   element and the XCON-URI of the conference from which a new
   conference is to be cloned in the <confObjID> element.

   An example of how a client can create a conference based on a
   blueprint is provided in Section 5.2.  The manner by which a client
   in this example might learn about a conference reservation or active
   conferences is similar to the first step in the blueprint example,
   with the exception of querying for different types of conference




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   objects supported by the specific conferencing system.  For instance,
   in this example, the client clones a conference reservation (i.e., an
   inactive conference).

   If the conferencing system can support a new instance of the specific
   type of conference (capabilities, etc.), then the request results in
   the creation of a conference, with an XCON-URI in the form of a new
   value in the <confObjID> parameter to reflect the newly cloned
   conference object returned in the confResponse message.

   Alice                          ConfS
    |                               |
    |(1)confRequest(confUserID,     |
    |       confObjID, create)      |
    |------------------------------>|
    |                 (a)Create +---|
    |                    Conf   |   |
    |                    Object |   |
    |                    & IDs  +-->|
    |                               |--+ (b) MS
    |                               |  | creates
    |                               |  | conf and
    |                               |<-+ its ID
    |                               |   (confid=Y)
    |                               |
    |(2)confResponse(confUserID,    |
    |      confObjID*,create,       |
    |      200, success,            |
    |      version, confInfo)       |
    |                               |
    |<------------------------------|
    |                               |
    '                               '

                 Figure 9: Create Basic Conference - Clone

   1.  Alice, a conferencing system client, sends a confRequest message
       to clone a conference based on an existing conference
       reservation.  Alice indicates this conference should be cloned
       from the specified parent conference represented by the XCON-URI
       in the <confObjID> provided in the request.

   2.  Upon receipt of the confRequest message containing a "create"
       <operation> and the aforementioned XCON-URI in the <confObjID>,
       the conference server ensures that such received XCON-URI is
       valid.  The conference server determines the appropriate read/
       write access of any users to be added to a conference based on
       this XCON-URI (using membership, roles, etc.).  The conference



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       server uses the received <confObjID> to clone a conference
       reservation.  The conference server also reserves or allocates a
       new XCON-URI (called "confObjID*" in Figure 9) to be used for the
       cloned conference object.  This new identifier is, of course,
       different from the one associated with the conference to be
       cloned, since it represents a different conference object.  Any
       subsequent protocol requests from any of the members of the
       conference must use this new identifier.  The conference server
       maintains the mapping between this conference ID and the parent
       conference object ID associated with the reservation through the
       conference instance, and this mapping is explicitly addressed
       through the <cloning-parent> element of the <conference-
       description> in the new conference object.

1. confRequest/create message (Alice clones an existing conference)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:type="ccmp:ccmp-conf-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:6845432@example.com</confObjID>
        <operation>create</operation>
        <ccmp:confRequest/>
     </ccmpRequest>
  </ccmp:ccmpRequest>

2. confResponse/create message (created conference
   object returned)

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
       xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
       xmlns:info="urn:ietf:params:xml:ns:conference-info"
       xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="ccmp:ccmp-conf-response-message-type">
       <confUserID>xcon-userid:Alice@example.com</confUserID>
       <confObjID>xcon:8977794@example.com</confObjID>
       <operation>create</operation>
       <response-code>200</response-code>
       <response-string>success</response-string>
       <version>1</version>



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       <ccmp:confResponse>
            <confInfo entity="xcon:8977794@example.com">
              <info:conference-description>
                  <info:display-text>
                     New conference by Alice cloned from 6845432
                  </info:display-text>
                   <info:maximum-user-count>10</info:maximum-user-count>
                   <info:available-media>
                          <info:entry label="11">
                              <info:type>audio</info:type>
                          </info:entry>
                   </info:available-media>
                   <xcon:cloning-parent>
                      xcon:6845432@example.com
                  </xcon:cloning-parent>
               </info:conference-description>
               <info:users>
                   <xcon:join-handling>allow</xcon:join-handling>
                      <xcon:allowed-users-list>
                     <xcon:target uri="sip:alice@example.com"
                                   method="dial-out"/>
                     <xcon:target uri="sip:bob83@example.com"
                                   method="dial-out"/>
                     <xcon:target uri="sip:carol@example.com"
                                   method="dial-out"/>
                   </xcon:allowed-users-list>
               </info:users>
                  <xcon:floor-information>
                     <xcon:floor-request-handling>
                        confirm</xcon:floor-request-handling>
                     <xcon:conference-floor-policy>
                       <xcon:floor id="1">
                        <xcon:media-label>11</xcon:media-label>
                       </xcon:floor>
                     </xcon:conference-floor-policy>
                  </xcon:floor-information>
              </confInfo>
          </ccmp:confResponse>
      </ccmpResponse>
  </ccmp:ccmpResponse>

       Figure 10: Create Basic Conference (Clone) Detailed Messaging

6.  Conference Users Scenarios and Examples

   Section 5 showed examples describing the several different ways a
   conference might be created using CCMP.  This section focuses on
   user-related scenarios, i.e., typical scenarios that may occur during



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   the lifetime of a conference, like adding new users and handling
   their media.  The following scenarios are based on those documented
   in the XCON framework.  The examples assume that a conference has
   already been correctly established, with media, if applicable, per
   one of the examples in Section 5.

6.1.  Adding a Party

   In this example, Alice wants to add Bob to an established conference.
   In the following example we assume Bob is a new user of the system,
   which means Alice also needs to provide some details about him.  In
   fact, the case of Bob already present as a user in the conferencing
   system is much easier to address, and will be discussed later.

    Alice          Bob
    CMCC1          CMCC2       CMCCx       ConfS
     |               |           |           |
     |(1) userRequest(confUserID,|           |
     |    confObjID, create,     |           |
     |    userInfo)  |           |           |
     |-------------------------------------->|
     |               |           |           |
     |               |        (a) Create +---|
     |               |           | Bob   |   |
     |               |           | as a  |   |
     |               |           | user  +-->|
     |               |           |           |
     |(2) userResponse(confUserID, confObjID |
     |      create, 200, success, userInfo)  |
     |<--------------------------------------|
     |               |           |           |
     |               |           | (b) Focus |
     |               |           |   sets up |
     |               |           | signaling |
     |               |           |    to Bob |
     |               |<----------------------|
     |               |           |           |
     |               |           | (c) Notify|
     |               |           | ("Bob just|
     |               |           |  joined") |
     |               |           |<----------|
     |               |           |           |
     '               '           '           '
     '               '           '           '
     '               '           '           '

        Figure 11: Client Manipulation of Conference - Add a Party




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   1.  Alice sends a userRequest message with an operation of "create"
       to add Bob to the specific conference as identified by the XCON-
       URI in the <confObjID>.  The "create" <operation> also makes sure
       that Bob is created as a user in the whole conferencing system.
       This is done by adding in the request a <userInfo> element
       describing Bob as a user.  This is needed in order to let the
       conferencing system be aware of Bob's characteristics.  In case
       Bob was already a registered user, Alice would just have
       referenced him through his XCON-USERID in the 'entity' attribute
       of the <userInfo> field, without providing additional data.  In
       fact, that data (including, for instance, Bob's SIP-URI to be
       used subsequently for dial-out) would be obtained by referencing
       the extant registration.  The conference server ensures that
       Alice has the appropriate authority based on the policies
       associated with that specific conference object to perform the
       operation.  As mentioned before, a new XCON-USERID is created for
       Bob, and the <userInfo> is used to update the conference object
       accordingly.  As already seen in Section 5.3, a placeholder
       wildcard ("xcon-userid:AUTO_GENERATE_1@example.com" in the CCMP
       messages below) is used for the 'entity' attribute of the
       <userInfo> element, to be replaced by the actual XCON-USERID
       later;

   2.  Bob is successfully added to the conference object, and an XCON-
       USERID is allocated for him ("xcon-userid:Bob@example.com"); this
       identifier is reported in the response as the value of the
       'entity' attribute of the returned <userInfo>;

   3.  In the presented example, the call signaling to add Bob to the
       conference is instigated through the focus as well.  As noted
       previously, this is implementation specific.  In fact, a
       conferencing system may accomplish different actions after the
       user creation, just as it may do nothing at all.  Among the
       possible actions, for instance, Bob may be added as a <target>
       element to the <allowed-users-list> element, whose joining
       'method' may be either "dial-in" or "dial-out".  Besides, out-of-
       band notification mechanisms may be involved as well, e.g., to
       notify Bob via mail of the new conference, including details as
       the date, password, expected participants, and so on (see
       Section 4.3).

      Once Bob has been successfully added to the specified conference,
      per updates to the state, and depending upon the policies, other
      participants (including Bob himself) may be notified of the
      addition of Bob to the conference via the conference notification
      service in use.





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1. userRequest/create message (Alice adds Bob)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:type="ccmp:ccmp-user-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>create</operation>
        <ccmp:userRequest>
          <userInfo entity="xcon-userid:AUTO_GENERATE_1@example.com">
              <info:display-text>Bob</info:display-text>
              <info:associated-aors>
                  <info:entry>
                    <info:uri>mailto:bob.depippis@example.com</info:uri>
                    <info:display-text>Bob's email</info:display-text>
                  </info:entry>
              </info:associated-aors>
              <info:endpoint entity="sip:bob83@example.com">
                  <info:display-text>Bob's laptop</info:display-text>
              </info:endpoint>
          </userInfo>
        </ccmp:userRequest>
    </ccmpRequest>
  </ccmp:ccmpRequest>

2. userResponse/create message (a new XCON-USERID is
   created for Bob and he is added to the conference)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="ccmp:ccmp-user-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>create</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
        <version>10</version>
        <ccmp:userResponse>
          <userInfo entity="xcon-userid:Bob@example.com">
              <info:display-text>Bob</info:display-text>
              <info:associated-aors>
                  <info:entry>



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                    <info:uri>mailto:bob.depippis@example.com</info:uri>
                    <info:display-text>Bob's email</info:display-text>
                  </info:entry>
              </info:associated-aors>
              <info:endpoint entity="sip:bob83@example.com">
                  <info:display-text>Bob's laptop</info:display-text>
              </info:endpoint>
          </userInfo>
        </ccmp:userResponse>
    </ccmpResponse>
  </ccmp:ccmpResponse>

                   Figure 12: Add Party Message Details

6.2.  Muting a Party

   This section provides an example of the muting of a party in an
   active conference.  We assume that the user to mute has already been
   added to the conference.  The document only addresses muting and not
   unmuting, since the latter would involve an almost identical CCMP
   message flow anyway.  However, if any external floor control is
   involved, whether a particular conferencing client can actually mute/
   unmute itself must be considered by the conferencing system.

      Please notice that interaction between CCMP and floor control
      should be carefully considered.  In fact, handling CCMP- and BFCP-
      based media control has to be considered as multiple layers: that
      is, a participant may have the BFCP floor granted, but be muted by
      means of CCMP.  If so, he would still be muted in the conference,
      and would only be unmuted if both the protocols allowed for this.

   Figure 13 provides an example of one client, Alice, impacting the
   media state of another client, Bob.  This example assumes an
   established conference.  In this example, Alice, who is the moderator
   of the conference, wants to mute Bob on a medium-sized multi-party
   conference, as his device is not muted (and he's obviously not
   listening to the call) and background noise in his office environment
   is disruptive to the conference.  BFCP floor control is assumed not
   to be involved.

   Muting can be accomplished using the <mute> control element
   associated with the target user's audio, in which case the conference
   server must update the settings associated with the user's media
   streams.  Muting/unmuting can also be accomplished by directly
   modifying the settings related to the target user's media streams,
   which is the approach shown in this example.  Specifically, Bob's
   <userInfo> is updated by modifying the <endpoint> element in the




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   <media> part related to audio information, identified by the 'id'
   attribute.  The modification consists in setting the audio <status>
   to "recvonly", in case of muting.

    Alice          Bob
    CMCC1          CMCC2       CMCCx        ConfS                MS
     |               |           |            |                  |
     |(1) userRequest(subject,   |            |                  |
     |    confUserID,confObjID,  |            |                  |
     |    update,userInfo)       |            |                  |
     |               |           |            |                  |
     |--------------------------------------->|                  |
     |               |           |            | Mute Bob         |
     |               |           |            |----------------->|
     |               |           |            |           200 OK |
     |               |           |            |<-----------------|
     |               |           |            |                  |
     |               |<====== XXX Bob excluded from mix XXX ====>|
     |               |           |            |                  |
     |               |         (a) Update +---|                  |
     |               |             Bob in |   |                  |
     |               |         data model |   |                  |
     |               |            (muted) +-->|                  |
     |               |           |            |                  |
     | (2)userResponse(confUserID,confObjID,  |                  |
     |           update,200,success,version)  |                  |
     |<---------------------------------------|                  |
     |               |           |            |                  |
     |               |           | (b) Notify |                  |
     |               |           |   ("Bob is |                  |
     |               |           |    muted") |                  |
     |               |           |<-----------|                  |
     |               |           |            |                  |
     '               '           '            '                  '
     '               '           '            '                  '
     '               '           '            '                  '

        Figure 13: Client Manipulation of Conference - Mute a Party

   1.  Alice sends a userRequest message with an "update" <operation>
       and the <userInfo> with the <status> field in the <media> element
       for Bob's <endpoint> set to "revconly".  In order to authenticate
       herself, Alice provides in the <subject> request parameter her
       registration credentials (i.e., username and password).  The
       <subject> parameter is an optional one: its use can be systematic
       whenever the conference server envisages to authenticate each





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       requester.  In such cases, if the client does not provide the
       required authentication information, the conferencing server
       answers with a CCMP "authenticationRequired" <response-code>,
       indicating that the request cannot be processed without including
       the proper <subject> parameter.  The conference server ensures
       that Alice has the appropriate authority based on the policies
       associated with that specific conference object to perform the
       operation.  It recognizes that Alice is allowed to request the
       specified modification, since she is moderator of the target
       conference, and updates the <userInfo> in the conference object
       reflecting that Bob's media is not to be mixed with the
       conference media.  If the conference server relies on a remote
       media server for its multimedia functionality, it subsequently
       changes Bob's media profile accordingly by means of the related
       protocol interaction with the MS.  An example describing a
       possible way of dealing with such a situation using the media
       server control architecture [RFC5567] is described in Figure 31,
       "Simple Bridging: Framework Transactions (2)", in [CALL-FLOWS].

   2.  A userResponse message with a "200" <response-code> ("success")
       is then sent to Alice.  Depending upon the policies, the
       conference server may notify other participants (including Bob)
       of this update via any conference notification service that may
       be in use.

 1. userRequest/update message (Alice mutes Bob)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:type="ccmp:ccmp-user-request-message-type">
       <subject>
          <username>Alice83</username>
          <conference-password>13011983</conference-password>
        </subject>
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>update</operation>
        <ccmp:userRequest>
            <userInfo entity="xcon-userid:Bob@example.com">
                <info:endpoint entity="sip:bob83@example.com">
                    <info:media id="1">
                        <info:label>123</info:label>
                        <info:status>recvonly</info:status>
                    </info:media>
                </info:endpoint>



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            </userInfo>
        </ccmp:userRequest>
    </ccmpRequest>
  </ccmp:ccmpRequest>

2. userResponse/update message (Bob has been muted)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
               xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
               xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:type="ccmp:ccmp-user-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>update</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
            <version>7</version>
        <ccmp:userResponse/>
    </ccmpResponse>
  </ccmp:ccmpResponse>

                      Figure 14: Mute Message Details

6.3.  Conference Announcements and Recordings

   This section deals with features that are typically required in a
   conferencing system, such as public announcements (e.g., to notify
   vocally that a new user joined a conference) and name recording.
   While this is not strictly CCMP-related (the CCMP signaling is
   actually the same as the one seen in Section 6.1), it is an
   interesting scenario to address to see how several components of an
   XCON-compliant architecture interact with each other to make it
   happen.

   In this example, as shown in Figure 15, Alice is joining Bob's
   conference that requires that she first enter a passcode.  After
   successfully entering the passcode, an announcement prompts Alice to
   speak her name so it can be recorded.  When Alice is added to the
   active conference, the recording is played back to all the existing
   participants.  A very similar example is presented in Figure 33 of
   [CALL-FLOWS].








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   CMCC  Alice                    ConfS                         MS
        |                            |                            |
        |(1)userRequest(confObjID,   |                            |
        |         create,userInfo)   |                            |
        |--------------------------->|                            |
        |                            |--+ Alice is                |
        |                            |  | new in the              |
        |                            |<-+ system (create          |
        |                            |    confUserID)             |
        |           ConfS handles +--|                            |
        |           SIP signaling |  |                            |
        |    (Alice<->ConfS<->MS) +->|                            |
        |                            |                            |
        |                            |--+ A password is           |
        |                            |  | required for            |
        |                            |<-+ that conference         |
        |                            |                            |
        |                            | Request IVR menu (PIN)     |
        |                            |--------------------------->|
        |                            |                            |
        |<========= MS gets PIN from Alice through DTMF =========>|
        |                            |                            |
        |                            |        Provided PIN is...  |
        |                            |<---------------------------|
        |                   Check +--|                            |
        |                     PIN |  |                            |
        |                         +->|                            |
        |                            |--+ Alice must              |
        |                            |  | record her              |
        |                            |<-+ name                    |
        |                            |                            |
        |                            | Request name recording     |
        |                            |--------------------------->|
        |                            |                            |
        |<========= MS records Alice's audio RTP (name) =========>|
        |                            |                            |
        |                            |            Audio recording |
        |                            |<---------------------------|
        |                Complete +--|                            |
        |                creation |  |                            |
        |                of Alice +->|                            |










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        |                            |                            |
        |                            |                            |
        | (2)userResponse(confUserID,|                            |
        |       confObjID,create,200,|                            |
        |           success,version) |                            |
        |<---------------------------|                            |
        |                            |                            |
        '                            '                            '

                  Figure 15: Recording and Announcements

   1.  Upon receipt of the userRequest message from Alice to be added to
       Bob's conference, the conference server determines that a
       password is required for this specific conference.  Thus, an
       announcement asking Alice to enter the password is sent back.
       This may be achieved by means of typical IVR functionality.  Once
       Alice enters the password, it is validated against the policies
       associated with Bob's active conference.  The conference server
       then connects to a server that prompts and records Alice's name.
       The conference server must also determine whether Alice is
       already a user of this conferencing system or whether she is a
       new user.  In this case, Alice is a new user for this
       conferencing system, so a new XCON-USERID is created for Alice.
       Based upon the contact information provided by Alice, the call
       signaling to add Alice to the conference is instigated through
       the focus.

   2.  The conference server sends Alice a userResponse message that
       includes in the <confUserID> the XCON-USERID assigned by the
       conferencing system to her.  This would allow Alice to later
       perform operations on the conference (if she were to have the
       appropriate policies), including registering for event
       notifications associated with the conference.  Once the call
       signaling indicates that Alice has been successfully added to the
       specific conference, per updates to the state, and depending upon
       the policies, other participants (e.g., Bob) are notified of the
       addition of Alice to the conference via the conference
       notification service and an announcement is provided to all the
       participants indicating that Alice has joined the conference.

  1. userRequest/create message  (a new conferencing system client,
     Alice, enters Bob's conference)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
       xmlns:info="urn:ietf:params:xml:ns:conference-info"
             xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
             xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">



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      <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:type="ccmp:ccmp-user-request-message-type">
          <confObjID>xcon:bobConf@example.com</confObjID>
          <operation>create</operation>
          <ccmp:userRequest>
            <userInfo entity="xcon-userid:AUTO_GENERATE_1@example.com">
                  <info:associated-aors>
                      <info:entry>
                          <info:uri>
                             mailto:Alice83@example.com
                          </info:uri>
                          <info:display-text>email</info:display-text>
                      </info:entry>
                  </info:associated-aors>
                  <info:endpoint entity="sip:alice_789@example.com"/>
              </userInfo>
          </ccmp:userRequest>
      </ccmpRequest>
  </ccmp:ccmpRequest>

  2. userResponse/create message (Alice provided with a new XCON-USERID
     and added to the conference)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
      xmlns:info="urn:ietf:params:xml:ns:conference-info"
      xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
      xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                    xsi:type="ccmp:ccmp-user-response-message-type">
          <confUserID>xcon-userid:Alice@example.com</confUserID>
          <confObjID>xcon:bobConf@example.com</confObjID>
          <operation>create</operation>
          <response-code>200</response-code>
          <response-string>success</response-string>
          <version>5</version>
          <ccmp:userResponse/>
      </ccmpResponse>
  </ccmp:ccmpResponse>

                 Figure 16: Announcement Messaging Details

6.4.  Monitoring for DTMF

   Conferencing systems also often need the capability to monitor for
   dual-tone multi-frequency (DTMF) from each individual participant.
   This would typically be used to enter the identifier and/or access
   code for joining a specific conference.  This feature is also often



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   exploited to achieve interaction between participants and the
   conferencing system for non-XCON-aware user agents (e.g., using DTMF
   tones to get muted/unmuted).

   An example of DTMF monitoring, within the context of the framework
   elements, is shown in Figure 15.  The media control architecture and
   protocols [RFC5567] can be used by the conference server for all the
   DTMF interactions.  Examples for DTMF interception in conference
   instances are presented in [CALL-FLOWS].

6.5.  Entering a Password-Protected Conference

   Some conferences may require a password to be provided by a user who
   wants to manipulate the conference objects (e.g., join, update,
   delete) via CCMP.  In this case, a password would be included in the
   <conference-password> element in the appropriate <conference-uris>
   entry of the conference data model.  Such password must be then
   included in the <conference-password> field in the CCMP request
   addressed to that conference.

   In the following example, Alice, a conferencing system client,
   attempts to join a password-protected conference.

   1.  Alice sends a userRequest message with a "create" <operation> to
       add herself in the conference with XCON-URI
       "xcon:8977777@example.com" (written in the <confObjID>
       parameter).  Alice provides her XCON-USERID via the <confUserID>
       field of the userRequest message and leaves out the <userInfo>
       one (first-party join).  In this first attempt, she doesn't
       insert any password parameter.

   2.  Upon receipt the userRequest/create message, the conference
       server detects that the indicated conference is not joinable
       without providing the appropriate passcode.  A userResponse
       message with a "423" <response-code> ("conference password
       required") is returned to Alice to indicate that her join has
       been refused and that she has to resend her request including the
       appropriate conference password in order to participate.

   3.  After getting the passcode through out-of-band mechanisms, Alice
       provides it in the proper <conference-password> request field of
       a new userRequest/create message and sends the updated request
       back to the server.

   4.  The conference server checks the provided password and then adds
       Alice to the protected conference.  After that, a userResponse
       message with a "200" <response-code> ("success") is sent to
       Alice.



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 1. userRequest/create message (Alice tries to enter the conference
    without providing the password)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpRequest
      xmlns:info="urn:ietf:params:xml:ns:conference-info"
            xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
            xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:type="ccmp:ccmp-user-request-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>create</operation>
         <ccmp:userRequest/>
     </ccmpRequest>
 </ccmp:ccmpRequest>

 2. userResponse/create message ("423", "conference password required")

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpResponse
     xmlns:info="urn:ietf:params:xml:ns:conference-info"
     xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
     xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:type="ccmp:ccmp-user-response-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>create</operation>
         <response-code>423</response-code>
         <response-string>conference password required</response-string>
         <ccmp:userResponse/>
     </ccmpResponse>
 </ccmp:ccmpResponse>

 3. userRequest/create message (Alice provides the password)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpRequest
      xmlns:info="urn:ietf:params:xml:ns:conference-info"
            xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
            xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:type="ccmp:ccmp-user-request-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>create</operation>
         <conference-password>8601</conference-password>



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         <ccmp:userRequest/>
     </ccmpRequest>
 </ccmp:ccmpRequest>

 4. userResponse/create message
    (Alice has been added to the conference)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpResponse
     xmlns:info="urn:ietf:params:xml:ns:conference-info"
     xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
     xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:type="ccmp:ccmp-user-response-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>create</operation>
         <response-code>200</response-code>
         <response-string>success</response-string>
         <version>10</version>
         <ccmp:userResponse/>
     </ccmpResponse>
 </ccmp:ccmpResponse>

      Figure 17: Password-Protected Conference Join Messages Details

7.  Sidebars Scenarios and Examples

   While creating conferences and manipulating users and their media are
   sufficient for many scenarios, there may be cases when more complex
   management is needed.

   In fact, a feature typically required in conferencing systems is the
   ability to create sidebars.  A sidebar is basically a child
   conference that usually includes a subset of the participants of the
   parent conference and a subset of its media as well.  Sidebars are
   typically required whenever some of the participants in a conference
   want a private discussion, without interfering with the main
   conference.

   This section deals with some typical scenarios using a sidebar, like
   whispering, private messaging, and coaching scenarios.  The first
   subsections present some examples of how a generic sidebar can be
   created, configured, and managed.







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7.1.  Internal Sidebar

   Figure 18 provides an example of one client, Alice, involved in an
   active conference with Bob and Carol.  Alice wants to create a
   sidebar to have a side discussion with Bob while still viewing the
   video associated with the main conference.  Alternatively, the audio
   from the main conference could be maintained at a reduced volume.
   Alice initiates the sidebar by sending a request to the ConfS to
   create a conference reservation based upon the active conference
   object.  Alice and Bob would remain on the roster of the main
   conference, such that other participants could be aware of their
   participation in the main conference, while an internal-sidebar
   conference is occurring.  Besides, Bob decides that he is not
   interested in still receiving the conference audio in background (not
   even at a lower volume as Alice configured) and so modifies the
   sidebar in order to make that stream inactive for him.

  Alice                   Bob                    ConfS
    |                      |                       |
    |(1) sidebarByValRequest(confUserID,           |
    |                  confObjID,create)           |
    |--------------------------------------------->|
    |                      |                       |
    |                      |        (a) Create +---|
    |                      |    sidebar-by-val |   |
    |                      |     (new conf obj |   |
    |                      |       cloned from +-->|
    |                      |        confObjID)     | Sidebar now has
    |                      |                       | id confObjID*
    |(2) sidebarByValResponse(confUserID,          | (parent mapping
    |     (confObjID*,create,200,success,          | conf<->sidebar)
    |         version,sidebarByValInfo)            |
    |<---------------------------------------------|
    |                      |                       |
    |(3) sidebarByValRequest                       |
    |       (confUserID, confObjID*,               |
    |       update,sidebarByValInfo)               |
    |--------------------------------------------->|
    |                      |                       |












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    |                      |        (b) Update +---|
    |                      |    sidebar-by-val |   |
    |                      |     (media, users |   |
    |                      |       etc.)       +-->|
    |                      |                       | Sidebar is
    |                      |                       | modified
    |(4) sidebarByValResponse(confUserID,          |
    |                 confObjID*, update,          |
    |              200, success, version)          |
    |<---------------------------------------------|
    |                      |                       |
    |                      |(5) userRequest        |
    |                      |      (confUserID',    |
    |                      |       confObjID*,     |
    |                      |       update,userInfo)|
    |                      |---------------------->|
    |                      |                       |
    |                      |        (c) Update +---|
    |                      |     user settings |   |
    |                      |     (Bob's media) |   |
    |                      |                   +-->|
    |                      |                       | Sidebar is modified
    |                      |                       | (original audio
    |                      |                       | inactive for Bob)
    |                      |(6) userResponse       |
    |                      |     (confUserID',     |
    |                      |      confObjID*,      |
    |                      |      update, 200,     |
    |                      |      success,version) |
    |                      |<----------------------|
    |                      |                       |
    '                      '                       '
    '                      '                       '
    '                      '                       '

            Figure 18: Client Creation of a Sidebar Conference

   1.  Upon receipt of CCMP sidebarByValRequest message to create a new
       sidebar based upon the conference whose XCON-URI is in the
       <confObjID> received in the request, the conference server uses
       such XCON-URI to clone a conference reservation for the sidebar.
       The sidebar reservation is NOT independent of the active main
       conference (i.e., parent).  The conference server also allocates
       a new XCON-URI ("confObjID*" in Figure 18) for that sidebar to be
       used for any subsequent protocol requests from any of the members
       of the conference.  The new XCON-URI is returned in the response
       message <confObjID> parameter.




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   2.  The relationship information is provided in the
       sidebarByValResponse message, specifically in the <sidebar-
       parent> element.  A dump of the complete representation of the
       main/parent conference is provided below as well to show how the
       cloning process for the creation of the sidebar could take place.

   3.  Upon receipt of the sidebarByValResponse message to reserve the
       conference, Alice can now create an active conference using that
       reservation or create additional reservations based upon the
       existing reservations.  In this example, Alice wants only Bob to
       be involved in the sidebar; thus, she manipulates the membership
       so that only the two of them appear in the <allowed-users-list>
       section.  Alice also wants both audio and video from the original
       conference to be available in the sidebar.  For what concerns the
       media belonging to the sidebar itself, Alice wants the audio to
       be restricted to the participants in the sidebar (that is, Bob
       and herself).  Additionally, Alice manipulates the media values
       to receive the audio from the main conference at a reduced
       volume, so that the communication between her and Bob isn't
       affected.  Alice sends a sidebarByValRequest message with an
       operation of "update" along with the <sidebarByValInfo>
       containing the aforementioned sidebar modifications.

   4.  Upon receipt of the sidebarByValRequest message to update the
       sidebar reservation, the conference server ensures that Alice has
       the appropriate authority based on the policies associated with
       that specific conference object to perform the operation.  The
       conference server must also validate the updated information in
       the reservation, ensuring that a member like Bob is already a
       user of this conference server.  Once the data for the conference
       identified by the <confObjID> is updated, the conference server
       sends a sidebarByValResponse message to Alice.  Depending upon
       the policies, the initiator of the request (i.e., Alice) and the
       participants in the sidebar (i.e., Bob) may be notified of his
       addition to the sidebar via the conference notification service.

   5.  At this point, Bob sends a userRequest message to the conference
       server with an operation of "update" to completely disable the
       background audio from the parent conference, since it prevents
       him from understanding what Alice says in the sidebar.

   6.  Notice that Bob's request only changes the media perspective for
       Bob.  Alice keeps on receiving both the audio from Bob and the
       background from the parent conference.  This request may be
       relayed by the conference server to the media server handling the
       mixing, if present.  Upon completion of the change, the





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       conference server sends a userResponse message to Bob.  Depending
       upon the policies, the initiator of the request (i.e., Bob) and
       the participants in the sidebar (i.e., Alice) may be notified of
       this change via the conference notification service.

   The following conference object represents the conference in which
   the sidebar is to be created.  It will be used by the conference
   server to create the new conference object associated with the
   sidebar.

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <info:conference-info
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                entity="xcon:8977878@example.com">
     <info:conference-description>
        <info:display-text>MAIN CONFERENCE</info:display-text>
        <info:conf-uris>
            <info:entry>
               <info:uri>sip:8977878@example.com</info:uri>
               <info:display-text>conference sip uri</info:display-text>
            </info:entry>
        </info:conf-uris>
        <info:available-media>
          <info:entry label="123">
            <info:display-text>main conference audio</info:display-text>
            <info:type>audio</info:type>
            <info:status>sendrecv</info:status>
          </info:entry>
          <info:entry label="456">
            <info:display-text>main conference video</info:display-text>
            <info:type>video</info:type>
            <info:status>sendrecv</info:status>
            <xcon:controls>
                    <xcon:video-layout>single-view</xcon:video-layout>
           </xcon:controls>
          </info:entry>
        </info:available-media>
    </info:conference-description>
    <info:conference-state>
        <info:active>true</info:active>
    </info:conference-state>
    <info:users>
        <info:user entity="xcon-userid:Alice@example.com">
            <info:display-text>Alice</info:display-text>
            <info:endpoint entity="sip:Alice@example.com">
                <info:media id="1">



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                    <info:label>123</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
                <info:media id="2">
                    <info:label>456</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
            </info:endpoint>
        </info:user>
        <info:user entity="xcon-userid:Bob@example.com">
            <info:display-text>Bob</info:display-text>
            <info:endpoint entity="sip:bob83@example.com">
                <info:media id="1">
                    <info:label>123</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
                <info:media id="2">
                    <info:label>456</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
            </info:endpoint>
        </info:user>
        <info:user entity="xcon-userid:Carol@example.com">
            <info:display-text>Carol</info:display-text>
            <info:endpoint entity="sip:carol@example.com">
                <info:media id="1">
                    <info:label>123</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
                <info:media id="2">
                    <info:label>456</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
            </info:endpoint>
        </info:user>
    </info:users>
  </info:conference-info>

             Figure 19: Conference with Alice, Bob, and Carol

   The sidebar creation happens through a cloning of the parent
   conference.  Once the sidebar is created, an update request makes
   sure that the sidebar is customized as needed.  The following
   protocol dump makes the process clearer.







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1. sidebarByValRequest/create message (Alice creates an
   internal sidebar)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
               xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
               xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>create</operation>
        <ccmp:sidebarByValRequest/>
    </ccmpRequest>
  </ccmp:ccmpRequest>

2. sidebarByValResponse/create message (sidebar returned)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
              xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
              xmlns:info="urn:ietf:params:xml:ns:conference-info"
              xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>create</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
            <version>1</version>
        <ccmp:sidebarByValResponse>
            <sidebarByValInfo entity="xcon:8974545@example.com">
                <info:conference-description>
                    <info:display-text>
                         SIDEBAR CONFERENCE registered by Alice
                    </info:display-text>
                    <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                  main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                  main conference video



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                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>
                <info:conference-state>
                    <info:active>false</info:active>
                </info:conference-state>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Bob@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Carol@example.com"/>
                    </xcon:allowed-users-list>
                    <xcon:sidebar-parent>
                         xcon:8977878@example.com
                    </xcon:sidebar-parent>
                </info:users>
            </sidebarByValInfo>
        </ccmp:sidebarByValResponse>
    </ccmpResponse>
  </ccmp:ccmpResponse>

3. sidebarByValRequest/update message (Alice updates the
   created sidebar)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
            xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
            xmlns:info="urn:ietf:params:xml:ns:conference-info"
            xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>update</operation>
        <ccmp:sidebarByValRequest>
            <sidebarByValInfo entity="xcon:8974545@example.com">
                <info:conference-description>
                  <info:display-text>
                        private sidebar Alice - Bob
                  </info:display-text>
                  <info:available-media>
                        <info:entry label="123">



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                            <info:display-text>
                                main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>recvonly</info:status>
                            <xcon:controls>
                                <xcon:gain>-60</xcon:gain>
                            </xcon:controls>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                main conference video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>recvonly</info:status>
                        </info:entry>
                        <info:entry label="AUTO_GENERATE_1">
                            <info:display-text>
                                sidebar audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                        <info:entry label="AUTO_GENERATE_2">
                            <info:display-text>
                                sidebar video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Bob@example.com"/>
                    </xcon:allowed-users-list>
                </info:users>
            </sidebarByValInfo>
        </ccmp:sidebarByValRequest>
    </ccmpRequest>
</ccmp:ccmpRequest>







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4. sidebarByValResponse/update message (sidebar's
   updates accepted)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>update</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
            <version>2</version>
        <ccmp:sidebarByValResponse/>
    </ccmpResponse>
  </ccmp:ccmpResponse>

5. userRequest/update message (Bob updates his media)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
           xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
           xmlns:info="urn:ietf:params:xml:ns:conference-info"
           xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
      <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:type="ccmp:ccmp-user-request-message-type">
        <confUserID>xcon-userid:Bob@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>update</operation>
        <ccmp:userRequest>
            <userInfo entity="xcon-userid:Bob@example.com">
                <info:endpoint entity="sip:bob83@example.com">
                    <info:media id="1">
                        <info:display-text>
                            main conference audio
                        </info:display-text>
                        <info:label>123</info:label>
                        <info:status>inactive</info:status>
                    </info:media>
                </info:endpoint>
            </userInfo>
        </ccmp:userRequest>
    </ccmpRequest>
</ccmp:ccmpRequest>




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6. userResponse/update message (Bob's preferences are set)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
               xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
               xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:type="ccmp:ccmp-user-response-message-type">
        <confUserID>xcon-userid:Bob@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>update</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
        <version>3</version>
        <ccmp:userResponse/>
    </ccmpResponse>
  </ccmp:ccmpResponse>

               Figure 20: Internal Sidebar Messaging Details

7.2.  External Sidebar

   Figure 21 provides an example of a different approach towards
   sidebars.  In this scenario, one client, Alice, is involved in an
   active conference with Bob, Carol, David, and Ethel.  Alice gets an
   important text message via a whisper from Bob that a critical
   customer needs to talk to Alice, Bob, and Ethel.  Alice creates a
   sidebar to have a side discussion with the customer Fred including
   the participants in the current conference with the exception of
   Carol and David, who remain in the active conference.  The difference
   from the previous scenario is that Fred is not part of the parent
   conference: this means that different policies might be involved,
   considering that Fred may access information coming from the parent
   conference, in case the sidebar was configured accordingly.  For this
   reason, in this scenario, we assume that Alice disables all the media
   from the original (parent) conference within the sidebar.  This means
   that, while in the previous example Alice and Bob still heard the
   audio from the main conference in background, this time no background
   is made available.  Alice initiates the sidebar by sending a request
   to the conference server to create a conference reservation based
   upon the active conference object.  Alice, Bob and Ethel would remain
   on the roster of the main conference in a hold state.  Whether or not
   the hold state of these participants is visible to other participants
   depends upon the individual and local policy.  However, providing the
   hold state allows the participants in the main conference to see that
   others in the conference are busy.  Note, that a separate conference
   could have been created by Alice to allow Bob and Ethel to talk to
   Fred.  However, creating a sidebar has somewhat of an advantage by



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   allowing the conference to be created using some of the same settings
   (e.g., role, floor control, etc.) that Bob and Ethel had in the main
   conference and it would allow for updates such that the media could
   be updated, for example, to provide audio from the main conference.

 Alice                   Bob                   ConfS
   |                      |                       |
   |(1) sidebarByRefRequest(confUserID,           |
   |                 confObjID, create)           |
   |--------------------------------------------->|
   |                      |                       |
   |                      |        (a) Create +---|
   |                      |    sidebar-by-ref |   |
   |                      |     (new conf obj |   |
   |                      |       cloned from +-->|
   |                      |        confObjID)     | Sidebar now has
   |                      |                       | id confObjID*
   |(2) sidebarByRefResponse(confUserID,          | (parent mapping
   |      confObjID*,create,200,success,          | conf<->sidebar)
   |           version,sidebarByRefInfo)          |
   |<---------------------------------------------|
   |                      |                       |
   |(3) sidebarByRefRequest(confUserID,           |
   |      confObjID*,update,sidebarByRefInfo)     |
   |--------------------------------------------->|
   |                      |                       |
   |                      |        (b) Create +---|
   |                      |      new user for |   |
   |                      |            Fred   |   |
   |                      |                   +-->|
   |                      |                       |
   |                      |        (c) Update +---|
   |                      |    sidebar-by-ref |   |
   |                      |     (media, users |   |
   |                      |     policy, etc.) +-->|
   |                      |                       | Sidebar is modified:
   |                      |                       | media from the
   |                      |                       | parent conference is
   |                      |                       | not available to
   |(4) sidebarByRefResponse(confUserID,          | anyone
   |                 confObjID*, update,          |
   |             200, success, version)           |
   |<---------------------------------------------|
   |                      |                       |







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   |                      |        Notify (Fred   |
   |                      |              added to |
   |                      |        sidebar users) |
   |                      |<----------------------|
   |                      |                       |
   '                      '                       '
   '                      '                       '
   '                      '                       '

             Figure 21: Client Creation of an External Sidebar

   1.  Upon receipt of the sidebarByRefRequest message to create a new
       sidebar conference, based upon the active conference specified by
       <confObjID> in the request, the conference server uses that
       active conference to clone a conference reservation for the
       sidebar.  The sidebar reservation is NOT independent of the
       active conference (i.e., parent).  The conference server, as
       before, allocates a new XCON-URI ("confObjID*" in Figure 21) to
       be used for any subsequent protocol requests toward the sidebar
       reservation.  The mapping between the sidebar XCON-URI and the
       one associated with the main conference is maintained by the
       conference server and it is gathered from the <sidebar-parent>
       element in the sidebar conference object.

   2.  Upon receipt of the sidebarByRefResponse message, which
       acknowledges the successful creation of the sidebar object, Alice
       decides that only Bob and Ethel, along with the new participant
       Fred are to be involved in the sidebar.  Thus, she manipulates
       the membership accordingly.  Alice also sets the media in the
       <conference-info> such that the participants in the sidebar don't
       receive any media from the main conference.  All these settings
       are provided to the conferencing server by means of a new
       sidebarByRefRequest message, with an "update" <operation>.

   3.  Alice sends the aforementioned sidebarByRefRequest message to
       update the information in the reservation and to create an active
       conference.  Upon receipt of the sidebarByRefRequest/update
       message, the conference server ensures that Alice has the
       appropriate authority based on the policies associated with that
       specific conference object to perform the operation.  The
       conference server also validates the updated information in the
       reservation.  Since Fred is a new user for this conferencing
       system, a conference user identifier (XCON-USERID) is created for
       Fred.  Specifically, Fred is added to the conference by only
       providing his SIP URI.  Based upon the contact information
       provided for Fred by Alice, the call signaling to add Fred to the
       conference may be instigated through the focus (e.g., if Fred had




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       a "dial-out" value for the 'method' attribute in his <target>
       field under <allowed-users-list>) at the actual activation of the
       sidebar.

   4.  The conference server sends a sidebarByRefResponse message and,
       depending upon the policies, the initiator of the request (i.e.,
       Alice) and the participants in the sidebar (i.e., Bob and Ethel)
       may be notified of his addition to the sidebar via the conference
       notification service.

1. sidebarByRefRequest/create message (Alice creates an
   external sidebar)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
               xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
               xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>create</operation>
        <ccmp:sidebarByRefRequest/>
    </ccmpRequest>
  </ccmp:ccmpRequest>

2. sidebarByRefResponse/create message (created
   sidebar returned)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8971212@example.com</confObjID>
            <operation>create</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
        <version>1</version>
        <ccmp:sidebarByRefResponse>
            <sidebarByRefInfo entity="xcon:8971212@example.com">
                <info:conference-description>
                    <info:display-text>
                        SIDEBAR CONFERENCE registered by Alice
                    </info:display-text>



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                    <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                 main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                 main conference video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>
                <info:conference-state>
                    <info:active>false</info:active>
                </info:conference-state>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Bob@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Carol@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:David@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:Ethel@example.com"/>
                    </xcon:allowed-users-list>
                    <xcon:sidebar-parent>
                        xcon:8977878@example.com
                    </xcon:sidebar-parent>
                </info:users>
            </sidebarByRefInfo>
        </ccmp:sidebarByRefResponse>
    </ccmpResponse>
  </ccmp:ccmpResponse>

3. sidebarByRefRequest/update message (Alice updates the sidebar)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"



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                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8971212@example.com</confObjID>
        <operation>update</operation>
        <ccmp:sidebarByRefRequest>
            <sidebarByRefInfo entity="xcon:8971212@example.com">
                <info:conference-description>
                    <info:display-text>
                        sidebar with Alice, Bob, Ethel and Fred
                    </info:display-text>
                    <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                 main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>inactive</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                 main conference video
                        </info:display-text>
                            <info:type>video</info:type>
                            <info:status>inactive</info:status>
                        </info:entry>
                        <info:entry label="AUTO_GENERATE_1">
                            <info:display-text>
                                 sidebar audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                        <info:entry label="AUTO_GENERATE_2">
                            <info:display-text>
                                 sidebar video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>sendrecv</info:status>
                            <xcon:controls>
                                 <xcon:video-layout>
                                       single-view
                                 </xcon:video-layout>
                            </xcon:controls>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>



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                <info:conference-state>
                    <info:active>false</info:active>
                </info:conference-state>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Bob@example.com"/>
                        <xcon:target method="dial-out"
                              uri="sip:fred@example.com"/>
                    </xcon:allowed-users-list>
                </info:users>
            </sidebarByRefInfo>
        </ccmp:sidebarByRefRequest>
    </ccmpRequest>
  </ccmp:ccmpRequest>

4. sidebarByRefResponse/update message (sidebar updated)

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
        <ccmp:ccmpResponse
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8971212@example.com</confObjID>
        <operation>update</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
        <version>2</version>
        <ccmp:sidebarByRefResponse/>
    </ccmpResponse>
  </ccmp:ccmpResponse>

               Figure 22: External Sidebar Messaging Details

7.3.  Private Messages

   The case of private messages can be handled as a sidebar with just
   two participants, similar to the example in Section 7.1.  Unlike the
   previous example, rather than using audio within the sidebar, Alice
   could just add an additional text-based media stream to the sidebar
   in order to convey her textual messages to Bob, while still viewing
   and listening to the main conference.




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   In this scenario, Alice requests to the conference server the
   creation of a private chat room within the main conference context
   (presented in Figure 19) in which the involved participants are just
   Bob and herself.  This can be achieved through the following CCMP
   transaction (Figure 23).

   1.  Alice forwards a sidebarByValRequest/create message to the
       conference server with the main conference XCON-URI in the
       <confObjID> parameter and the desired sidebar conference object
       in the <sidebarByValInfo> field.  In this way, a sidebar creation
       using user-provided conference information is requested from the
       conference server.  Please note that, unlike the previous sidebar
       examples, in this case, a completely new conference object to
       describe the sidebar is provided: there is no cloning involved,
       while the <confObjID> still enforces the parent-child
       relationship between the main conference and the to-be-created
       sidebar.

   2.  The conference server, after checking Alice's rights and
       validating the conference object carried in the request, creates
       the required sidebar-by-val conference and a new XCON-URI for it.
       Instead of cloning the main conference object, as shown in
       Sections 7.1 and 7.2, the sidebar is created on the basis of the
       user-provided conference information.  However, the parent
       relationship between the main conference and the newly created
       sidebar is still maintained by the conference server (as a
       consequence of the chosen CCMP request message type -- the
       sidebarByVal one) and it is reflected by the <sidebar-parent>
       element in the <sidebarByValInfo> element returned in the
       sidebarByValResponse message.  Please notice that, according to
       the CCMP specification, the return of the created sidebar data in
       this kind of "success" response is not mandatory.

1. sidebarByValRequest/create message (Alice creates a private
   chat room between Bob and herself)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest
            xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
            xmlns:info="urn:ietf:params:xml:ns:conference-info"
            xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8977878@example.com</confObjID>
        <operation>create</operation>
        <ccmp:sidebarByValRequest>
            <sidebarByValInfo entity="xcon:AUTO_GENERATE_1@example.com">



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                <info:conference-description>
                  <info:display-text>
                        private textual sidebar alice - bob
                  </info:display-text>
                  <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>recvonly</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                main conference video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>recvonly</info:status>
                        </info:entry>
                        <info:entry label="AUTO_GENERATE_2">
                            <info:display-text>
                                sidebar text
                            </info:display-text>
                            <info:type>text</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Bob@example.com"/>
                    </xcon:allowed-users-list>
                </info:users>
            </sidebarByValInfo>
        </ccmp:sidebarByValRequest>
    </ccmpRequest>
</ccmp:ccmpRequest>

2. sidebarByValResponse/create message (sidebar returned)

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
              xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
              xmlns:info="urn:ietf:params:xml:ns:conference-info"
              xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">



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    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
        <confUserID>xcon-userid:Alice@example.com</confUserID>
        <confObjID>xcon:8974545@example.com</confObjID>
        <operation>create</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
            <version>1</version>
        <ccmp:sidebarByValResponse>
            <sidebarByValInfo entity="xcon:8974545@example.com">
                <info:conference-description>
                    <info:display-text>
                        private textual sidebar alice - bob
                    </info:display-text>
                    <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>recvonly</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                main conference video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>recvonly</info:status>
                        </info:entry>
                        <info:entry label="789">
                            <info:display-text>
                                sidebar text
                            </info:display-text>
                            <info:type>text</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                    <xcon:sidebar-parent>
                         xcon:8977878@example.com
                    </xcon:sidebar-parent>
                </info:conference-description>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Alice@example.com"/>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:Bob@example.com"/>
                    </xcon:allowed-users-list>



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                </info:users>
            </sidebarByValInfo>
        </ccmp:sidebarByValResponse>
    </ccmpResponse>
  </ccmp:ccmpResponse>

             Figure 23: Sidebar for Private Messages Scenario

7.4.  Observing and Coaching

   "Observing and Coaching" is one of the most interesting sidebar-
   related scenarios.  In fact, it highlights two different interactions
   that have to be properly coordinated.

   An example of observing and coaching is shown in Figure 25.  In this
   example, call center agent Bob is involved in a conference with
   customer Carol.  Since Bob is a new agent and Alice sees that he has
   been on the call with Carol for longer than normal, she decides to
   observe the call and coach Bob as necessary.  Of course, the
   conferencing system must make sure that the customer Carol is not
   aware of the presence of the coach Alice.  This makes the use of a
   sidebar necessary for the success of the scenario.

   Consider the following as the conference document associated with the
   video conference involving Bob (the call agent) and Carol (the
   customer) (Figure 24):

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <info:conference-info
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                entity="xcon:8978383@example.com">
     <info:conference-description>
        <info:display-text>
                CUSTOMER SERVICE conference
        </info:display-text>
        <info:conf-uris>
            <info:entry>
               <info:uri>sip:8978383@example.com</info:uri>
               <info:display-text>conference sip uri</info:display-text>
            </info:entry>
        </info:conf-uris>
        <info:available-media>
          <info:entry label="123">
            <info:display-text>service audio</info:display-text>
            <info:type>audio</info:type>
            <info:status>sendrecv</info:status>



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          </info:entry>
          <info:entry label="456">
            <info:display-text>service video</info:display-text>
            <info:type>video</info:type>
            <info:status>sendrecv</info:status>
            <xcon:controls>
                    <xcon:video-layout>single-view</xcon:video-layout>
           </xcon:controls>
          </info:entry>
        </info:available-media>
    </info:conference-description>
    <info:conference-state>
        <info:active>true</info:active>
    </info:conference-state>
    <info:users>
        <info:user entity="xcon-userid:bob@example.com">
            <info:display-text>Bob - call agent</info:display-text>
            <info:endpoint entity="sip:bob@example.com">
                <info:media id="1">
                    <info:label>123</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
                <info:media id="2">
                    <info:label>456</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
            </info:endpoint>
        </info:user>
        <info:user entity="xcon-userid:carol@example.com">
            <info:display-text>Carol - customer</info:display-text>
            <info:endpoint entity="sip:carol@example.com">
                <info:media id="1">
                    <info:label>123</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
                <info:media id="2">
                    <info:label>456</info:label>
                    <info:status>sendrecv</info:status>
                </info:media>
            </info:endpoint>
        </info:user>
    </info:users>
  </info:conference-info>

            Figure 24: A Call-Center Conference Object Example






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Alice                   Bob                    ConfS
  |                      |                       |
  |(1) sidebarByRefRequest(confUserID,           |
  |                 confObjID, create)           |
  |--------------------------------------------->|
  |                      |                       |
  |                      |        (a) Create +---|
  |                      |    sidebar-by-ref |   |
  |                      |     (new conf obj |   |
  |                      |       cloned from +-->|
  |                      |        confObjID)     | Sidebar now has
  |                      |                       | id confObjID*
  |(2) sidebarByRefResponse(confUserID,          | (parent mapping
  |      confObjID*,create,200,success,          | conf<->sidebar)
  |           version,sidebarByRefInfo)          |
  |<---------------------------------------------|
  |                      |                       |
  |(3) sidebarByRefRequest(confUserID,           |
  |      confObjID*,update,sidebarByRefInfo)     |
  |--------------------------------------------->|
  |                      |                       |
  |                      |        (b) Update +---|
  |                      |    sidebar-by-val |   |
  |                      |     (media, users |   |
  |                      |     policy, etc.) +-->|
  |                      |                       | Sidebar is modified:
  |                      |                       | unilateral sidebar
  |                      |                       | audio, Carol excluded
  |                      |                       | from the sidebar
  |(4) sidebarByRefResponse(confUserID,          |
  |                 confObjID*, update,          |
  |               200, success, version)         |
  |<---------------------------------------------|
  |                      |                       |
  |                      |         Notify (Bob   |
  |                      |    he's been added to |
  |                      |        sidebar users) |
  |                      |<----------------------|
  |                      |                       |
  '                      '                       '
  '                      '                       '
  '                      '                       '

      Figure 25: Supervisor Creating a Sidebar for Observing/Coaching







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   1.  Upon receipt of the sidbarByRefRequest/create message from Alice
       to create a new sidebar conference from the <confObjID> received
       in the request, the conference server uses the received active
       conference to clone a conference reservation for the sidebar.
       The conference server also allocates a new XCON-URI to be used
       for any subsequent protocol requests directed to the new sidebar.
       The conference server maintains the mapping between this sidebar
       conference ID and the one associated with the main conference
       instance.  The conference server sends a sidebarByRefResponse
       message with the new XCON-URI in the <confObjID> field and other
       relevant information in the <sidebarByRefInfo>.

   2.  Upon receipt of the sidebarByRefResponse message, Alice
       manipulates the data received in the <sidebarByRefInfo> in the
       response.  Alice wants only Bob to be involved in the sidebar;
       thus, she updates the <allowed-users-list> to include only Bob
       and herself.  Alice also wants the audio to be received by
       herself and Bob from the original conference, but wants any
       outgoing audio from herself to be restricted to the participants
       in the sidebar, whereas Bob's outgoing audio should go to the
       main conference, so that both Alice and the customer Carol hear
       the same audio from Bob.  Alice sends a sidebarByRefRequest
       message with an "update" <operation> including the updated
       sidebar information in the <sidebarByRefInfo> element.

   3.  Upon receipt of the sidebarByRefRequest/update message, the
       conference server ensures that Alice has the appropriate
       authority based on the policies associated with that specific
       conference object to perform the operation.  In order to request
       the insertion of a further media stream in the sidebar (i.e., in
       this example an audio stream from Alice to Bob), the requester
       has to provide a new <entry> element in the <available-media>
       field of the <sidebarByRefInfo>.  The mandatory 'label' attribute
       of that new <entry> is filled with a dummy value
       "AUTO_GENERATE_1", but it will contain the real server-generated
       media stream identifier when the media stream is effectively
       allocated on the server side.  Similarly, the mandatory 'id'
       attribute in the <media> element referring to the new sidebar
       audio stream under both Alice's and Bob's <endpoint> contains a
       wildcard value, respectively, "AUTO_GENERATE_2" and
       "AUTO_GENERATE_3": those values will be replaced with the
       appropriated server-generated identifiers upon the creation of
       the referred media stream.  We are assuming the conference server
       is able to recognize those dummy values as placeholders.

   4.  After validating the data, the conference server sends a
       sidebarByRefResponse message.  Based upon the contact information
       provided for Bob by Alice, the call signaling to add Bob to the



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       sidebar with the appropriate media characteristics is instigated
       through the focus.  Bob is notified of his addition to the
       sidebar via the conference notification service; thus, he is
       aware that Alice, the supervisor, is available for coaching him
       through this call.

1. sidebarByRefRequest/create message (Alice as coach creates a sidebar)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
               xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
               xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
        <confUserID>xcon-userid:alice@example.com</confUserID>
        <confObjID>xcon:8978383@example.com</confObjID>
        <operation>create</operation>
        <ccmp:sidebarByRefRequest/>
    </ccmpRequest>
</ccmp:ccmpRequest>

2. sidebarByRefResponse/create message (sidebar created)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
        <confUserID>xcon-userid:alice@example.com</confUserID>
        <confObjID>xcon:8971313@example.com</confObjID>
        <operation>create</operation>
        <response-code>200</response-code>
        <response-string>Success</response-string>
        <version>1</version>
        <ccmp:sidebarByRefResponse>
            <sidebarByRefInfo entity="xcon:8971313@example.com">
                <info:conference-description>
                    <info:display-text>
                        SIDEBAR CONFERENCE registered by alice
                    </info:display-text>
                    <info:available-media>
                        <info:entry label="123">
                            <info:display-text>
                                 main conference audio
                            </info:display-text>
                            <info:type>audio</info:type>



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                            <info:status>sendrecv</info:status>
                        </info:entry>
                        <info:entry label="456">
                            <info:display-text>
                                 main conference video
                            </info:display-text>
                            <info:type>video</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                    <xcon:sidebar-parent>
                        xcon:8971313@example.com
                    </xcon:sidebar-parent>
                </info:conference-description>
                <info:conference-state>
                    <info:active>false</info:active>
                </info:conference-state>
                <info:users>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:alice@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:bob@example.com"/>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:carol@example.com"/>
                    </xcon:allowed-users-list>
                </info:users>
            </sidebarByRefInfo>
        </ccmp:sidebarByRefResponse>
    </ccmpResponse>
  </ccmp:ccmpResponse>

  3. sidebarByRefRequest/update message (Alice introduces unilateral
     sidebar audio and excludes Carol from the sidebar)

  <ccmp:ccmpRequest
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
        <confUserID>xcon-userid:alice@example.com</confUserID>
        <confObjID>xcon:8971313@example.com</confObjID>
        <operation>update</operation>
        <ccmp:sidebarByRefRequest>
            <sidebarByRefInfo entity="xcon:8971313@example.com">





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                <info:conference-description>
                    <info:display-text>
                        Coaching sidebar Alice and Bob
                    </info:display-text>
                    <info:available-media>
                        <info:entry label="AUTO_GENERATE_1">
                            <info:display-text>
                                 Alice-to-Bob audio
                            </info:display-text>
                            <info:type>audio</info:type>
                            <info:status>sendrecv</info:status>
                        </info:entry>
                    </info:available-media>
                </info:conference-description>
                <info:conference-state>
                    <info:active>false</info:active>
                </info:conference-state>
                <info:users>
                    <info:user entity="xcon-userid:alice@example.com">
                      <info:endpoint entity="sip:alice@example.com">
                        <info:media id="AUTO_GENERATE_2">
                         <info:label>AUTO_GENERATE_1</info:label>
                         <info:status>sendonly</info:status>
                        </info:media>
                      </info:endpoint>
                    </info:user>
                    <info:user entity="xcon-userid:bob@example.com">
                      <info:endpoint entity="sip:bob@example.com">
                        <info:media id="AUTO_GENERATE_3">
                         <info:label>AUTO_GENERATE_1</info:label>
                         <info:status>recvonly</info:status>
                        </info:media>
                      </info:endpoint>
                    </info:user>
                    <xcon:allowed-users-list>
                        <xcon:target method="dial-in"
                              uri="xcon-userid:alice@example.com"/>
                        <xcon:target method="dial-out"
                              uri="xcon-userid:bob@example.com"/>
                    </xcon:allowed-users-list>
                </info:users>
            </sidebarByRefInfo>
        </ccmp:sidebarByRefRequest>
    </ccmpRequest>
  </ccmp:ccmpRequest>






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4. sidebarByRefRequest/update message (updates accepted)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpResponse
                xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
                xmlns:info="urn:ietf:params:xml:ns:conference-info"
                xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
    <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
        <confUserID>xcon-userid:alice@example.com</confUserID>
        <confObjID>xcon:8971313@example.com</confObjID>
        <operation>update</operation>
        <response-code>200</response-code>
        <response-string>success</response-string>
        <version>2</version>
        <ccmp:sidebarByRefResponse/>
    </ccmpResponse>
 </ccmp:ccmpResponse>

            Figure 26: Coaching and Observing Messaging Details

8.  Removing Participants and Deleting Conferences

   The following scenarios detail the basic operations associated with
   removing participants from conferences and entirely deleting
   conferences.  The examples assume that a conference has already been
   correctly established, with media, if applicable, per one of the
   examples in Section 5.

8.1.  Removing a Party

   Figure 27 provides an example of a client, Alice, removing another
   participant, Bob, from a conference.  This example assumes an
   established conference with Alice, Bob, Claire, and Duck.  In this
   example, Alice wants to remove Bob from the conference so that the
   group can continue in the same conference without Bob's
   participation.














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   Alice            Bob       Claire       ConfS
     |               |           |           |
     |(1) userRequest(confUserID,|           |
     |         confObjID, delete,|           |
     |         userInfo)         |           |
     |-------------------------------------->|
     |               |           |           |
     |               |           | (a) Focus |
     |               |           | tears down|
     |               |           | signaling |
     |               |           |  to Bob   |
     |               |<----------------------|
     |               |                       |
     |               |         (b)Deletes+---|
     |               |           | Bob   |   |
     |               |           | as a  |   |
     |               |           | user  +-->|
     |               |           | in        |
     |               |           | confObj   |
     |               |           |           |
     |(2) userResponse(confUserID,confObjID, |
     |           delete,200,success,version) |
     |<--------------------------------------|
     |               |           |           |
     |               |           |           |
     |               |           | (c) Notify|
     |               |           | ("Bob just|
     |               |           |  left")   |
     |               |           |<----------|
     |               |           |           |
     '               '           '           '
     '               '           '           '
     '               '           '           '

       Figure 27: Client Manipulation of Conference - Remove a Party

   1.  Alice sends a userRequest message with a "delete" <operation>.
       The conference server ensures that Alice has the appropriate
       authority based on the policies associated with that specific
       conference object to perform the operation.

   2.  Based upon the contact and media information in the conference
       object for Bob in the <userInfo> element, the conferencing system
       starts the process to remove Bob (e.g., the call signaling to
       remove Bob from the conference is instigated through the focus).
       The conference server updates the data in the conference object,
       thus, removing Bob from the <users> list.  After updating the
       data, the conference server sends a userResponse message to



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       Alice.  Depending upon the policies, other participants (e.g.,
       Claire) may be notified of the removal of Bob from the conference
       via the conference notification service.

 1. userRequest/delete message (Alice deletes Bob)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:type="ccmp:ccmp-user-request-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>delete</operation>
         <ccmp:userRequest>
             <userInfo entity="xcon-userid:Bob@example.com"/>
         </ccmp:userRequest>
     </ccmpRequest>
 </ccmp:ccmpRequest>

 2. userResponse/delete message (Bob has been deleted)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpResponse
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:type="ccmp:ccmp-user-response-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
             <operation>delete</operation>
         <response-code>200</response-code>
         <response-string>success</response-string>
         <version>17</version>
         <ccmp:userResponse/>
     </ccmpResponse>
 </ccmp:ccmpResponse>

            Figure 28: Removing a Participant Messaging Details









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8.2.  Deleting a Conference

   In this section, an example of a successful conference deletion is
   provided (Figure 29).

   Alice                          ConfS
    |                               |
    |(1)confRequest(confUserID,     |
    |       confObjID, delete)      |
    |------------------------------>|
    |                 (a)Delete +---|
    |                    Conf   |   |
    |                    Object |   |
    |                           +-->|
    |                               |--+ (b) MS
    |                               |  | removes related
    |                               |  | mixer instances and
    |                               |<-+ their participants
    |                               |    (SIP signaling as well)
    |                               |
    |(2)confResponse(confUserID,    |
    |      confObjID,delete,200,    |
    |      success)                 |
    |                               |
    |<------------------------------|
    |                               |
    '                               '

                     Figure 29: Deleting a Conference

   1.  The conferencing system client Alice sends a confRequest message
       with a "delete" operation to be performed on the conference
       identified by the XCON-URI carried in the <confObjID> parameter.
       The conference server, on the basis of the <confUserID> included
       in the receipt request, ensures that Alice has the appropriate
       authority to fulfill the operation.

   2.  After validating Alice's rights, the conference server instigates
       the process to delete the conference object, disconnecting
       participants and removing associated resources such as mixer
       instances.  Then, the conference server returns a confResponse
       message to Alice with "200" as <response-code> and the deleted
       conference XCON-URI in the <confObjID> field.








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 1. confRequest/delete message (Alice deletes a conference)

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpRequest
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:type="ccmp:ccmp-conf-request-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>delete</operation>
         <ccmp:confRequest/>
     </ccmpRequest>
 </ccmp:ccmpRequest>

 2. confResponse/delete message ("200", "success")

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <ccmp:ccmpResponse
        xmlns:info="urn:ietf:params:xml:ns:conference-info"
        xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
        xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
     <ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:type="ccmp:ccmp-conf-response-message-type">
         <confUserID>xcon-userid:Alice@example.com</confUserID>
         <confObjID>xcon:8977794@example.com</confObjID>
         <operation>delete</operation>
         <response-code>200</response-code>
         <response-string>success</response-string>
         <ccmp:confResponse/>
     </ccmpResponse>
 </ccmp:ccmpResponse>

            Figure 30: Deleting a Conference Messaging Details

9.  Security Considerations

   The security considerations applicable to the implementation of these
   call flows are documented in the XCON framework, with additional
   security considerations documented in the CCMP document.  Statements
   with regard to the necessary security are discussed in particular
   flows; however, this is for informational purposes only.  The
   implementer is encouraged to carefully consider the security
   requirements in the normative documents.






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10.  Acknowledgements

   The detailed content for this document is derived from the prototype
   work of Lorenzo Miniero, Simon Pietro Romano, Tobia Castaldi, and
   their colleagues at the University of Napoli.

11.  References

11.1.  Normative References

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

   [RFC6501]  Novo, O., Camarillo, G., Morgan, D., and J. Urpalainen,
              "Conference Information Data Model for Centralized
              Conferencing (XCON)", RFC 6501, March 2012.

   [RFC6502]  Camarillo, G., Srinivasan, S., Even, R., and J.
              Urpalainen, "Conference Event Package Data Format
              Extension for Centralized Conferencing (XCON)", RFC 6502,
              March 2012.

   [RFC6503]  Barnes, M., Boulton, C., Romano, S., and H. Schulzrinne,
              "Centralized Conferencing Manipulation Protocol",
              RFC 6503, March 2012.

   [W3C.REC-xml-20081126]
              Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E., and
              F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
              Edition)", World Wide Web Consortium Recommendation REC-
              xml-20081126, November 2008,
              <http://www.w3.org/TR/2008/REC-xml-20081126>.

11.2.  Informative References

   [CALL-FLOWS]
              Amirante, A., Castaldi, T., Miniero, L., and S. Romano,
              "Media Control Channel Framework (CFW) Call Flow
              Examples", Work in Progress, July 2011.

   [RFC3261]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
              A., Peterson, J., Sparks, R., Handley, M., and E.
              Schooler, "SIP: Session Initiation Protocol", RFC 3261,
              June 2002.

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



Barnes, et al.                Informational                    [Page 76]

RFC 6504                 CCMP Call Flow Examples              March 2012


   [RFC4579]  Johnston, A. and O. Levin, "Session Initiation Protocol
              (SIP) Call Control - Conferencing for User Agents",
              BCP 119, RFC 4579, August 2006.

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

   [RFC4597]  Even, R. and N. Ismail, "Conferencing Scenarios",
              RFC 4597, August 2006.

   [RFC5567]  Melanchuk, T., "An Architectural Framework for Media
              Server Control", RFC 5567, June 2009.

   [RFC6505]  McGlashan, S., Melanchuk, T., and C. Boulton, "A Mixer
              Control Package for the Media Control Channel Framework",
              RFC 6505, March 2012.



































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RFC 6504                 CCMP Call Flow Examples              March 2012


Authors' Addresses

   Mary Barnes
   Polycom
   TX
   USA

   EMail: mary.ietf.barnes@gmail.com


   Lorenzo Miniero
   Meetecho
   Via Carlo Poerio 89/a
   Napoli  80121
   Italy

   EMail: lorenzo@meetecho.com


   Roberta Presta
   University of Napoli
   Via Claudio 21
   Napoli  80125
   Italy

   EMail: roberta.presta@unina.it


   Simon Pietro Romano
   University of Napoli
   Via Claudio 21
   Napoli  80125
   Italy

   EMail: spromano@unina.it
















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