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Versions: (draft-barnes-xcon-ccmp) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 RFC 6503

XCON Working Group                                             M. Barnes
Internet-Draft                                                    Nortel
Intended status: Standards Track                              C. Boulton
Expires: September 11, 2009                              NS-Technologies
                                                             S P. Romano
                                                    University of Napoli
                                                          H. Schulzrinne
                                                     Columbia University
                                                          March 10, 2009


             Centralized Conferencing Manipulation Protocol
                        draft-ietf-xcon-ccmp-02

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
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   This Internet-Draft will expire on September 11, 2009.

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   Copyright (c) 2009 IETF Trust and the persons identified as the
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   Please review these documents carefully, as they describe your rights
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Abstract

   The Centralized Conferencing Manipulation Protocol (CCMP) can create,
   retrieve, change and delete objects describing a centralized
   conference, such as state and capabilities of the conference,
   participants, and their roles.  The conference information is
   contained in XML documents and fragments conforming to the
   centralized conferencing data model schema.  CCMP is a state-less
   client-server protocol based on a request/response model.
   Conferencing clients send requests to conference servers, which
   respond to the client with the conference information.

   This document also discusses options for using existing notification
   protocols to inform conference client about the changes in the state
   of a conference during its entire lifetime.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Conventions  . . . . . . . . . . . . . . . . . . . . . . . . .  5
   3.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  6
   4.  Protocol Overview  . . . . . . . . . . . . . . . . . . . . . .  7
   5.  System Architecture  . . . . . . . . . . . . . . . . . . . . .  8
   6.  Conference Object and User Identifiers . . . . . . . . . . . . 10
     6.1.  Conference Object  . . . . . . . . . . . . . . . . . . . . 10
     6.2.  Conference Users and Participants  . . . . . . . . . . . . 10
   7.  Protocol Operations  . . . . . . . . . . . . . . . . . . . . . 12
     7.1.  Implementation Approach  . . . . . . . . . . . . . . . . . 13
     7.2.  CCMP protocol messages . . . . . . . . . . . . . . . . . . 13
       7.2.1.  CCMP Request Message . . . . . . . . . . . . . . . . . 13
       7.2.2.  CCMP Response Message  . . . . . . . . . . . . . . . . 14
         7.2.2.1.  CCMP Response Codes  . . . . . . . . . . . . . . . 15
       7.2.3.  Detailed CCMP Messages . . . . . . . . . . . . . . . . 16
         7.2.3.1.  blueprintsRequest and blueprintsResponse
                   messages . . . . . . . . . . . . . . . . . . . . . 20
         7.2.3.2.  confsRequest and confsResponse messages  . . . . . 21
         7.2.3.3.  blueprintRequest and blueprintResponse messages  . 22
         7.2.3.4.  confRequest and confResponse messages  . . . . . . 25
         7.2.3.5.  usersRequest and usersResponse messages  . . . . . 28
         7.2.3.6.  userRequest and userResponse messages  . . . . . . 31
         7.2.3.7.  sidebarsByValRequest and sidebarsByValResponse
                   messages . . . . . . . . . . . . . . . . . . . . . 33
         7.2.3.8.  sidebarByValRequest and sidebarByValResponse
                   messages . . . . . . . . . . . . . . . . . . . . . 34
         7.2.3.9.  sidebarsByRefRequest and sidebarsByRefResponse
                   messages . . . . . . . . . . . . . . . . . . . . . 36
         7.2.3.10. sidebarByRefRequest and sidebarByRefResponse



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                   messages . . . . . . . . . . . . . . . . . . . . . 37
   8.  A complete example of the CCMP in action . . . . . . . . . . . 40
     8.1.  Alice retrieves the available blueprints . . . . . . . . . 40
     8.2.  Alice gets detailed information about a specific
           blueprint  . . . . . . . . . . . . . . . . . . . . . . . . 43
     8.3.  Alice creates a new conference through a cloning
           operation  . . . . . . . . . . . . . . . . . . . . . . . . 45
     8.4.  Alice updates conference information . . . . . . . . . . . 47
     8.5.  Alice inserts a list of users in the conference object . . 49
     8.6.  Alice joins the conference . . . . . . . . . . . . . . . . 51
     8.7.  Alice adds a new user to the conference  . . . . . . . . . 52
   9.  Locating a Conference Control Server . . . . . . . . . . . . . 55
   10. XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 57
   11. Managing notifications . . . . . . . . . . . . . . . . . . . . 69
   12. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 70
     12.1. URN Sub-Namespace Registration . . . . . . . . . . . . . . 70
     12.2. XML Schema Registration  . . . . . . . . . . . . . . . . . 70
     12.3. MIME Media Type Registration for 'application/ccmp+xml'  . 71
     12.4. DNS Registrations  . . . . . . . . . . . . . . . . . . . . 72
       12.4.1. Registration  of a Location Server Application
               Service Tag  . . . . . . . . . . . . . . . . . . . . . 72
       12.4.2. Registration of a Location Server Application
               Protocol Tag for HELD  . . . . . . . . . . . . . . . . 72
     12.5. CCMP Protocol Registry . . . . . . . . . . . . . . . . . . 73
       12.5.1. CCMP Message Types . . . . . . . . . . . . . . . . . . 73
       12.5.2. CCMP Response Codes  . . . . . . . . . . . . . . . . . 74
   13. Security Considerations  . . . . . . . . . . . . . . . . . . . 76
   14. Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 77
   15. Changes since last Version . . . . . . . . . . . . . . . . . . 78
   16. References . . . . . . . . . . . . . . . . . . . . . . . . . . 79
     16.1. Normative References . . . . . . . . . . . . . . . . . . . 79
     16.2. Informative References . . . . . . . . . . . . . . . . . . 79
   Appendix A.  Appendix A: Other protocol models and transports
                considered for CCMP . . . . . . . . . . . . . . . . . 81
     A.1.  Using SOAP for the CCMP  . . . . . . . . . . . . . . . . . 81
     A.2.  A RESTful approach for the CCMP  . . . . . . . . . . . . . 82
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 83














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1.  Introduction

   The Framework for Centralized Conferencing [RFC5239] (XCON Framework)
   defines a signaling-agnostic framework, naming conventions and
   logical entities required for building advanced conferencing systems.
   The XCON Framework introduces the conference object as a logical
   representation of a conference instance, representing the current
   state and capabilities of a conference.

   The Centralized Conferencing Manipulation Protocol (CCMP) defined in
   this document allows authenticated and authorized users to create,
   manipulate and delete conference objects.  Operations on conferences
   include adding and removing participants, changing their roles, as
   well as adding and removing media streams and associated end points.

   The CCMP implements the client-server model within the XCON
   Framework, with the conferencing client and conference control server
   acting as client and server, respectively.  The CCMP uses HTTP
   [RFC2616] as the protocol to transfer the CCMP requests and
   responses, which contain the domain-specific XML-encoded data objects
   defined in the Conference Information Data Model for Centralized
   Conferencing (XCON Data Model) [I-D.ietf-xcon-common-data-model].
   Other protocol models such as the use of a REST (REpresentational
   State Transfer) architectural style [REST] were considered.  However,
   the CCMP is a request/response protocol with new or updated data
   relevant to the specific conference object returned in the response.
   Whereas, a REST approach involves singular/monolithic operations on
   data, with the response typically indicating either success or
   failure, rather than providing updated data based on a specific
   operation, thus, it was not considered a good choice.  Details of the
   use of REST for the CCMP, as well as other protocols considered
   (e.g., SOAP) are provided in Appendix A.

   Section 4 provides an overview of the design of the CCMP, followed by
   the system architecture in Section 5.  Section 6 discusses the
   primary keys in the conference object carried in the protocol.  An
   overview of the operations associated with each protocol request and
   response is provided in Section 7.  A complete example of the
   operation of the CCMP, describing a typical call flow associated with
   conference creation and manipulation, is provided in Section 8.
   Section 10 provides the XML schema.










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2.  Conventions

   In this document, the key words "MUST", "MUST NOT", "REQUIRED",
   "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT
   RECOMMENDED", "MAY", and "OPTIONAL" are to be interpreted as
   described in BCP 14, RFC 2119 [RFC2119] and indicate requirement
   levels for compliant implementations.












































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3.  Terminology

   In additon to the terms defined in the Framework for Centralized
   Conferencing [RFC5239], this document uses the following terms and
   acronyms:

   CRUD:  CRUD stands for Create/Read/Update/Delete and indicates a
      design pattern supporting creating, retrieving, updating and
      destroying objects.

   REST:  REpresentational State Transfer (REST) is an architectural
      style, i.e., a coordinated set of architectural constraints.  REST
      is based on the consideration that a software architecture can
      often be specified as an appropriate configuration of components,
      data and connectors, all coordinated through constraining their
      mutual relationships.  Coordination and constraints help achieve a
      desired set of architectural properties.  [REST]

   SOAP:  Simple Object Access Protocol defined in
      [W3C.REC-soap12-part1-20030624] and
      [W3C.REC-soap12-part2-20030624].






























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4.  Protocol Overview

   This document specifies the basic operations that can create,
   retrieve, modify and delete conference-related information in a
   centralized conference.  The core set of objects includes conference
   blueprints, the conference itself, users, and sidebars.

   Each update operation in the protocol model is atomic and either
   succeeds or fails as a whole.  Thus, a server has to first check all
   parameters, before making any changes to the internal representation
   of the conference object.  For example, it would be undesirable to
   change the <subject> of the conference, but then detect an invalid
   URI in one of the <service-uris> and abort the remaining updates.

   Because multiple clients can modify the same conference objects,
   clients need to obtain the current object and then update the whole
   object.

   Editor's Note: Do we need locking, using WebDAV or floor control?
   Otherwise, changes made by user A could get lost when user B wants to
   modify some other parameter.  For example, A changes the subject, B
   adds the a service URI.

   It is likely that implementations and future standardization work
   will add more conference attributes and parameters.  There are three
   types of extensions.  The first and simplest type of extension adds
   elements to the overall conference description, media descriptions or
   descriptions of users.  The XML namespace mechanism makes such
   extensions relatively easy, although implementations still have to
   deal with implementations that may not understand the new namespaces.
   The CCMP "blueprintsRequest" message allows clients to determine the
   capabilities of a specific server, reflected by the specific
   blueprints supported by that server.

   A second type of extension replaces the conference, user or media
   objects with completely new schema definitions, i.e., the namespaces
   for these objects themselves differ from the basic one defined in
   this document.  As long as the OPTIONS request remains available and
   keeps to a mutually-understood definition, a compatible client and
   server will be able to bootstrap themselves into using these new
   objects.

   Finally, it is conceivable that new object types are needed beyond
   the core conference, user and media objects and their children.
   These would also be introduced by namespaces and new URIs.






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5.  System Architecture

   CCMP supports the XCON framework .  Figure 1 depicts a subset of the
   'Conferencing System Logical Decomposition' architecture from the
   XCON framework document.  It illustrates the role that CCMP assumes
   within the overall centralized architecture.


   ........................................................
   .  Conferencing System                                 .
   .                                                      .
   .        +---------------------------------------+     .
   .        |   C O N F E R E N C E   O B J E C T   |     .
   .      +-+-------------------------------------+ |     .
   .      |   C O N F E R E N C E   O B J E C T   | |     .
   .    +-+-------------------------------------+ | |     .
   .    |   C O N F E R E N C E   O B J E C T   | | |     .
   .    |                                       | | |     .
   .    |                                       | |-+     .
   .    |                                       |-+       .
   .    +---------------------------------------+         .
   .                        ^                             .
   .                        |                             .
   .                        v                             .
   .               +-------------------+                  .
   .               | Conference Control|                  .
   .               | Server            |                  .
   .               +-------------------+                  .
   .                        ^                             .
   .........................|..............................
                            |
                            |Conference
                            |Control
                            |Manipulation
                            |Protocol
                            |
   .........................|..............................
   .                        V                             .
   .                +----------------+                    .
   .                | Conference     |                    .
   .                | Control        |                    .
   .                | Client         |                    .
   .                +----------------+                    .
   .                                                      .
   .  Conferencing Client                                 .
   ........................................................





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                  Figure 1: Conference Client Interaction

   CCMP serves as the Conference Control Protocol, allowing the
   conference control client to interface with the conference object
   maintained by the conferencing system, as represented in Figure 1.
   Conference Control is one part of functionality for advanced
   conferencing supported by a conferencing client.  Other functions are
   discussed in the XCON framework and related documents.











































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6.  Conference Object and User Identifiers

   This section provides an overview of the conference object and
   conference users which are key protocol elements for creating the
   CCMP requests and responses.  The identifiers used in CCMP for the
   conference object (XCON-URI) and conference user (XCON-USERID) are
   introduced in the XCON framework and defined in the XCON data model
   [I-D.ietf-xcon-common-data-model].

6.1.  Conference Object

   Conference objects feature a simple dynamic inheritance-and-override
   mechanism.  Conference objects are linked into a tree, where each
   tree node inherits attributes from its parent node.  The roots of
   these inheritance trees are also known as "blueprints".  Nodes in the
   inheritance tree can be active conferences or simply descriptions
   that do not currently have any resources associated with them.  An
   object can mark certain of its properties as unalterable, so that
   they cannot be overridden.

   The schema for the conference object is defined in the XCON data
   model.  Conference objects are uniquely identified by the XCON-URI.
   A client MAY specify a parent element that indicates the parent from
   which the conference is to inherit values.  When creating
   conferences, the XCON-URI included by the client is only a
   suggestion.  To avoid identifier collisions and to conform to local
   server policy, the conference control server MAY choose a different
   identifier.

6.2.  Conference Users and Participants

   Each conference can have zero or more users.  All conference
   participants are users, but some users may have only administrative
   functions and do not contribute or receive media.  Users are added
   one user at a time to simplify error reporting.  Users are inherited
   as well, so that it is easy to set up a conference that has the same
   set of participants or a common administrator.  The Conference
   Control Server creates individual users, assigning them a unique
   Conference User Identifier (XCON-USERID).

   A variety of elements defined in the common <conference-info> element
   as specified in the XCON data model are used to determine how a
   specific user expects and is allowed to join a conference as a
   participant or as a user with specific privileges (e.g., observer).
   For example, the <method> attribute defines how the caller joins the
   conference, with a set of defined XML elements, namely <dial-in> for
   users that are allowed to dial in and <dial-out> for users that the
   conference focus will be trying to reach. <dial-in> is the default.



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   If the conference is currently active, dial-out users are contacted
   immediately; otherwise, they are contacted at the start of the
   conference.  The conference control server assigns a unique
   Conference User Identifier (XCON-USERID) to each user.  The
   conference control server uses the XCON-USERID to change or delete
   <user> elements.  Depending upon policies and privileges, specific
   users MAY also manipulate <user> elements.

   In many conferences, users can dial in if they know the XCON-URI and
   an access code shared by all conference participants.  In this case,
   the system is typically not aware of the call signaling URL.  Thus,
   the initial <user> element does not have an entity attribute and the
   default type of <dial-in> is used to support this type of user.  For
   this case, the server assigns a locally-unique URI, such as a
   locally-scoped tel URI.  The conference control server assigns a
   unique Conference User Identifier (XCON-USERID) to these users when
   they dial-in to join the conference.  If the user supports the
   notification event package [I-D.ietf-xcon-event-package], they can
   receive their XCON-USERID, thus allowing them to also manipulate the
   <user> attribute, including the entity attribute, in the conference
   object.






























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7.  Protocol Operations

   CCMP is a client-server, XML-based, stateless protocol, which has
   been specifically conceived to provide users with the necessary means
   for the creation, retrieval, modification and deletion of conference
   objects.  Conference-related information is encapsulated into CCMP
   messages in the form of documents or document fragments compliant
   with the XCON data model representation.

   The main operations provided by CCMP belong in four general
   categories:

   create:  for the creation of a conference, a conference user, a
      sidebar, or a blueprint.

   retrieve:  to get information about the current state of either a
      conference object (be it an actual conference or a blueprint, or a
      sidebar) or a conference user.  A retrieve operation can also be
      used to obtain the XCON-URIs of the active conferences and/or
      blueprints available at the server.

   update:  to modify the current features of a specified conference or
      conference user.

   delete:  to remove from the system a conference object or a
      conference user.

   Thus, the main targets of CCMP operations are:

   o  conference objects associated with either active or registered
      conferences,

   o  conference objects associated with blueprints,

   o  conference objects associated with sidebars, both embedded in the
      main conference (i.e. <sidebars-by-value> elements) and external
      to it (i.e. <sidebars-by-ref> elements),

   o  <user> elements associated with conference users,

   o  the list of XCON-URIs related to conferences and blueprints
      available at the server, for which only retrieval operations are
      allowed.








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7.1.  Implementation Approach

   There have been a number of different proposals as to the most
   suitable implementation solution for the CCMP.  A non-exhaustive
   summary of the most interesting ones is provided in Appendix A.  The
   proposed solution for the CCMP is viewed as a good compromise amongst
   the most notable past candidates and is referred to as 'HTTP single
   verb transport plus CCMP body'.  With this approach, CCMP is able to
   take advantage of existing HTTP functionality.  As with SOAP, the
   CCMP uses a 'single HTTP verb' for transport (i.e. a single
   transaction type for each request/response pair); this allows
   decoupling CCMP messages from HTTP messages.  Similarly, as with any
   RESTful approach, CCMP messages are inserted directly in the body of
   HTTP messages, thus avoiding any unnecessary processing and
   communication burden associated with further intermediaries.  With
   this approach, no modification to the CCMP messages/operations is
   required to use a different transport protocol.

   The remainder of this document focuses on the selected approach.  The
   CCMP protocol inserts XML-based CCMP requests into the body of HTTP
   POST operations and retrieves responses from the body of HTTP '200
   OK' messages.  CCMP messages have a MIME-type of "application/
   ccmp+xml", which appears inside the "Content-Type" and "Accept"
   fields of HTTP requests and responses.

7.2.  CCMP protocol messages

   CCMP messages are either requests or responses.  The general CCMP
   request message is defined in Section 7.2.1.  The general CCMP
   response message is defined in Section 7.2.2.  The details of the
   specific message type which is carried in the CCMP request and
   response messages are described in Section 7.2.3.

7.2.1.  CCMP Request Message

   A CCMP request message is comprised of the following parameters:

   confUserId:  A mandatory parameter containing the XCON-URI of the
      client.  This parameter is REQUIRED by the conferencing server for
      system specific Authorization, Authentication and Accounting (AAA)
      procedures.

   confObjId:  an optional parameter containing, whenever necessary, the
      XCON-URI of the target conference object;







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   specialized request message:  this is specialization of the generic
      request message (e.g., blueprintsRequest), containing parameters
      that are dependent on the specific request sent to the server, the
      details of which are provided in Section 7.2.3




   <xs:element name="ccmpRequest" type="ccmp-request-type" />

   <!-- CCMP request definition -->

   <xs:complexType name="ccmp-request-type">
           <xs:sequence>
                   <xs:element name="ccmpRequest"
                           type="ccmp-request-message-type" />
           </xs:sequence>
   </xs:complexType>

   <!--  Definition of ccmp-request-message-type -->

      <xs:complexType abstract="true"
           name="ccmp-request-message-type">
           <xs:sequence>
                   <xs:element name="confUserID" type="xs:string"
                           minOccurs="1" maxOccurs="1" />
                   <xs:element name="confObjID" type="xs:string"
                           minOccurs="0" maxOccurs="1" />
           </xs:sequence>
      </xs:complexType>



               Figure 2: Structure of CCMP Request messages

7.2.2.  CCMP Response Message

   A CCMP response message is comprised of the following parameters:

   confUserId:  A mandatory parameter containing the XCON-URI of the
      client which issued the request

   confObjId:  An optional parameter containing the XCON-URI of the
      target conference object







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   responseCode:  A mandatory parameter containing the response code
      associated with the request, chosen among the codes listed in
      Section 7.2.2.1

   specialized response message:  This is specialization of the generic
      response message, containing parameters that are dependent on the
      specific request sent to the server(e.g., blueprintsResponse), the
      details of which are provided in Section 7.2.3




   <xs:element name="ccmpResponse" type="ccmp-response-type" />

   <!-- CCMP response definition -->

   <xs:complexType name="ccmp-response-type">
           <xs:sequence>
                   <xs:element name="ccmpResponse"
                           type="ccmp-response-message-type" />
           </xs:sequence>
   </xs:complexType>

    <!--  Definition of ccmp-response-message-type -->

      <xs:complexType abstract="true"
           name="ccmp-response-message-type">
           <xs:sequence>
                   <xs:element name="confUserID" type="xs:string"
                           minOccurs="0" maxOccurs="1" />
                   <xs:element name="confObjID" type="xs:string"
                           minOccurs="0" maxOccurs="1" />
                   <xs:element ref="response-code" minOccurs="1"
                           maxOccurs="1" />
           </xs:sequence>
      </xs:complexType>


               Figure 3: Structure of CCMP Response message

7.2.2.1.  CCMP Response Codes

   All CCMP response messages MUST include a "responseCode".  The
   following summarizes the CCMP response codes:







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   success:  Successful completion of the requested operation.

   modified:  Successful completion of the requested operation, with
      partial data returned in the confObjID having been modified from
      the data included in the confObjID included request, either for a
      "create" or a "change" operation

   badRequest:  Syntactically malformed request

   objectNotFound:  Target object missing at the server

   unauthorized:  User not allowed to perform the required operation

   forbidden:  Operation not allowed (e.g., cancellation of a blueprint)

   forbiddenDeleteParent:  Cancel operation failed since the target
      object is a parent of child objects which depend on it, or because
      it effects, based on the 'parent-enforceable' mechanism, the
      corresponding element in a child object

   forbiddenChangeProtected:  Update refused by the server because the
      target element cannot be modified due to its implicit dependence
      on the value of a parent object ('parent-enforceable' mechanism)

   requestTimeout:  The time required to serve the request has exceeded
      the envisaged service threshold

   serverInternalError:  The server cannot complete the required service
      due to a system internal error

   notImplemented:  Operation envisaged in the protocol, but not
      implemented in the contacted server.

7.2.3.  Detailed CCMP Messages

   Based on the request and response message structures described in
   Section 7.2.1 and Section 7.2.2, the following summarizes the
   specialized CCMP request/response types described in this document:

   1.   blueprintsRequest/blueprintsResponse

   2.   confsRequest/confsResponse

   3.   blueprintRequest/blueprintResponse

   4.   confRequest/confResponse





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   5.   usersRequest/usersResponse

   6.   userRequest/userResponse

   7.   sidebarsByValRequest/sidebarsByValResponse

   8.   sidebarsByRefRequest/sidebarsByRefResponse

   9.   sidebarByValRequest/sidebarByValResponse

   10.  sidebarByRefRequest/sidebarByRefResponse

   These CCMP request/response pairs use the fundamental CCMP operations
   as defined in Section 7 to manipulate the conference data.  Table 1
   summarizes the CCMP operations and corresponding actions that are
   valid for a specific CCMP request type, noting that neither the
   blueprintsRequest/blueprints/Response or confsRequest/ConfsResponse
   require an "operation" parameter.  The corresponding response MUST
   contain the same operation.  Note that some entries are labeled "N/A"
   indicating the operation is invalid for that request type.  In the
   case of an "N/A*", the operation MAY be allowed for specific
   privileged users or system administrators, but is not part of the
   functionality included in this document.




























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   +---------------+------------+------------+------------+------------+
   | Operation     |  Retrieve  |   Create   |   Update   |   Delete   |
   | ------------- |            |            |            |            |
   | -Request Type |            |            |            |            |
   +---------------+------------+------------+------------+------------+
   | blueprintsReq |  Get list  |     N/A    |     N/A    |     N/A    |
   | uest          |     of     |            |            |            |
   |               | blueprints |            |            |            |
   |               | .          |            |            |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | blueprintRequ |     Get    |    N/A*    |    N/A*    |    N/A*    |
   | est           | blueprint. |            |            |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | confsRequest  |  Get list  |     N/A    |     N/A    |     N/A    |
   |               |     of     |            |            |            |
   |               | conference |            |            |            |
   |               | s (active, |            |            |            |
   |               |     etc.)  |            |            |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | confRequest   |    Gets    |   Creates  |   Changes  |   Deletes  |
   |               | conference | conference | conference | conference |
   |               |  object or |   object   |   object   |  Object as |
   |               | blueprint. |            |            |  a whole.  |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | usersRequest  |   Gets a   |     N/A    |   Adds or  |     N/A    |
   |               |  specific  |            |  modifies  |            |
   |               |    users   |            |     the    |            |
   |               |  element.  |            |  specified |            |
   |               |            |            |    users   |            |
   |               |            |            |  element.  |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | userRequest   |   Gets a   |   Creates  |   Adds or  |  Deletes a |
   |               |  specific  | XCON-UserI |  modifies  |    user    |
   |               |    user    | D     .    |     the    | element as |
   |               |  element.  |            |  specified |  a whole.  |
   |               |            |            |    user    |            |
   |               |            |            |  element.  |            |
   |               |            |            |            |            |



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   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | sidebarsByVal |    Gets    |     N/A    |     N/A    |     N/A    |
   | Request       | sidebars-b |            |            |            |
   |               | y   -val   |            |            |            |
   |               |    element |            |            |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | sidebarsByRef |    Gets    |     N/A    |     N/A    |     N/A    |
   | Request       | sidebars-b |            |            |            |
   |               | y   -ref   |            |            |            |
   |               |    element |            |            |            |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | sidebarByValR |   Gets a   |     N/A    |   Adds or  | Removes/de |
   | equest        |   sidebar  |            | modifies a | l etes the |
   |               |  element.  |            |  sidebar.  |    entire  |
   |               |            |            |            |   sidebar. |
   |               |            |            |            |            |
   | ------------- | ---------- | ---------- | ---------- | ---------- |
   |               |            |            |            |            |
   | sidebarByRefR |   Gets a   |     N/A    |   Adds or  | Removes/de |
   | equest        |   sidebar  |            | modifies a | l etes the |
   |               |  element.  |            |  sidebar.  |    entire  |
   |               |            |            |            |   sidebar. |
   +---------------+------------+------------+------------+------------+

            Table 1: Request Type Operation Specific Processing

   The following additional parameters are included in the specialized
   CCMP request/response messages detailed in the subsequent sections:

   operation:  An optional parameter for each CCMP request/response
      message.  This parameter is REQUIRED in all messages except for
      the "blueprintRequest", "blueprintResponse", "confsRequest" and
      "confsResponse" messages.

   blueprintInfo:  An optional parameter used for the blueprintResponse
      message.  It is of type "conference-type" as defined in the XCON
      data model and contains the data of the conference object
      representing the blueprint in the conference server.  This
      parameter SHOULD not be included in any other response type
      messages and SHOULD only be included in a "create", "update" or
      "delete" operation for a blueprintRequest message in special cases
      where a user has special privileges such as an administrator.




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   blueprintsInfo:  An optional parameter used for the
      blueprintsResponse message.  It contains a list of elements of
      type "blueprintInfo".  This parameter SHOULD not be included in
      any other response type messages and SHOULD only be included in a
      "create", "update" or "delete" operation for a blueprintRequest
      message in special cases where a user has special privileges such
      as an administrator.

   confsInfo:  An optional parameter used for the confsResponse message.
      It contains a list of XCON-URIs.  This parameter SHOULD not be
      included in any other response type messages and SHOULD only be
      included in a "create", "update" or "delete" operation for a
      blueprintRequest message in special cases where a user has special
      privileges such as an administrator.

   usersInfo:  An OPTIONAL parameter that MAY be included in a
      usersRequest and usersReponse message, depending upon the
      operation.  The 'usersInfo' parameter carries an object compliant
      with the <users> field of the XCON data model.

7.2.3.1.  blueprintsRequest and blueprintsResponse messages

   A 'blueprintsRequest' (Figure 4) message is sent to request the list
   of XCON-URIs associated with the available blueprints from the
   conference server.  Such URIs can be subsequently used by the client
   to access detailed information about a specified blueprint with a
   specific 'blueprintRequest' message per Section 7.2.3.3.  A
   'blueprintsRequest' message REQUIRES no additional parameters beyond
   those specified for the basic CCMP request message.  The associated
   'blueprintsResponse' message SHOULD contain, as shown in Figure 4, a
   'blueprintsInfo' parameter containing the above mentioned XCON-URI
   list.  The 'confObjId' parameter is NOT REQUIRED in the request or
   response for this transaction.


















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    <!-- blueprintsRequest -->
    <xs:complexType name="ccmp-blueprints-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type"/>
           </xs:complexContent>
    </xs:complexType>

   <!-- blueprintsResponse -->
   <xs:complexType name="ccmp-blueprints-response-message-type">
   <xs:complexContent>
           <xs:extension base="tns:ccmp-response-message-type">
                   <xs:sequence>
                           <xs:element ref="blueprintsResponse"/>
                   </xs:sequence>
           </xs:extension>
   </xs:complexContent>
   </xs:complexType>

    <!-- blueprintsResponseType -->

   <xs:element name="blueprintsResponse"
               type="blueprintsResponseType"/>

   <xs:complexType name="blueprintsResponseType">
     <xs:sequence>
         <xs:element name="blueprintsInfo"
                     type="info:uris-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>



    Figure 4: Structure of the blueprintsRequest and blueprintsResponse
                                 messages

7.2.3.2.  confsRequest and confsResponse messages

   A 'confsRequest' message is used to retrieve, from the server, the
   list of XCON-URIs associated with active and registered conferences A
   'confsRequest' message REQUIRES no additional parameters beyond those
   specified for the basic CCMP request message.  The associated
   'confsResponse' message SHOULD contain the list of XCON-URIs in the
   'confsInfo' parameter.  The 'confObjId' parameter is NOT REQUIRED for
   this transaction.  A user, upon receipt of the response message, can
   interact with the available conference objects through further CCMP
   messages.  The 'confsRequest' message is of a "retrieve-only" type,
   since the sole purpose is to collect information available at the
   conference server.  Thus, an 'operation' parameter SHOULD NOT be



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   included in a 'confsRequest' message.



   <!-- confsRequest -->
   <xs:complexType name="ccmp-confs-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type"/>
           </xs:complexContent>
   </xs:complexType>

   <!-- confsResponse -->
   <xs:complexType name="ccmp-confs-response-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-response-message-type">
                           <xs:sequence>
                                   <xs:element ref="confsResponse" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- confsResponseType -->

   <xs:element name="confsResponse" type="confsResponseType"/>

     <xs:complexType name="confsResponseType">
     <xs:sequence>
        <xs:element name="confsInfo"
                    type="info:uris-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>



    Figure 5: Structure of the confsRequest and confsResponse messages

7.2.3.3.  blueprintRequest and blueprintResponse messages

   Through a 'blueprintRequest', a client can manipulate the conference
   object associated with a specified blueprint.  The request MUST
   include an 'operation' parameter and a 'confObjId' parameter.  Only
   the "retrieve" 'operation' SHOULD should be included in a
   'blueprintRequest message.  The 'create', 'update' and 'delete'
   operations SHOULD NOT be included in a 'blueprintRequest' message
   except in the case of privileged users (e.g. the conference server
   administration staff).  The 'confObjId' parameter contains the XCON-
   URI of the blueprint, which might have been previously retrieved



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   through a 'blueprintsRequest' message.

   In the case of responseCode of "success" for a 'retrieve' operation,
   the 'blueprintInfo' parameter SHOULD be included in the
   'blueprintResponse' message.  Inside responses, the 'blueprintInfo'
   parameter carries the conference document associated with the
   blueprint specified in the request.












































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   <!--  blueprintRequest -->
   <xs:complexType name="ccmp-blueprint-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type">
                           <xs:sequence>
                                   <xs:element ref="blueprintRequest" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- blueprintRequestType -->

   <xs:element name="blueprintRequest" type="blueprintRequestType"/>

   <xs:complexType name="blueprintRequestType">
     <xs:sequence>
        <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
        <xs:element name="blueprintInfo"
                    type="info:conference-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>

   <!-- blueprintResponse -->
    <xs:complexType name="ccmp-blueprint-response-message-type">
           <xs:complexContent>
            <xs:extension base="tns:ccmp-response-message-type">
                    <xs:sequence>
          <xs:element ref="blueprintResponse"/>
                    </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
    </xs:complexType>

    <!-- blueprintResponseType -->

    <xs:element name="blueprintResponse" type="blueprintResponseType"/>

      <xs:complexType name="blueprintResponseType">
      <xs:sequence>
         <xs:element name="blueprintInfo" type="info:conference-type"/>
      </xs:sequence>
    </xs:complexType>



     Figure 6: Structure of the blueprintRequest and blueprintResponse



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                                 messages

7.2.3.4.  confRequest and confResponse messages

   With a 'confRequest' message, CCMP clients can manipulate conference
   objects associated with either active or registered conferences
   (blueprints or reservations).  The request MUST include an
   'operation' parameter.  Depending upon the type of 'operation' a
   'confObjId' parameter and/or 'confInfo' parameter MAY be included.
   The 'confObjId' parameter contains the XCON-URI of the specific
   active or registered conference.  The 'confInfo' parameter contains
   the conference data that is the target of the 'confRequest' - i.e.
   the <conference-info> document (compliant with the XCON data model
   structure).

   To create a new conference through a 'confRequest' message, two
   approaches can be embraced:

   1.  Creation through explicit cloning: the 'confObjId' parameter MUST
       contain the XCON-URI of the blueprint to be cloned, while the
       'confInfo' parameter SHOULD NOT be included in the request;

   2.  Creation through implicit cloning (also known as "direct
       creation"): the 'confObjId' parameter SHOULD NOT be included in
       the request, whereas the 'confInfo' parameter describing the
       conference to be created MUST be included in the request.

   In both cases, a successful completion of the request carries back a
   responseCode of 'success' and SHOULD contain, in the 'confObjId'
   parameter, the XCON-URI of the created conference.  In addition, the
   'confInfo' parameter transporting the created conference document
   SHOULD be included.  Obviously, the newly created object can be
   manipulated by the client through subsequent 'update' operations.

   In the case of 'retrieve' or 'delete' operations, the 'confObjId'
   representing the XCON-URI of the target conference MUST be included
   and the 'confInfo' SHOULD NOT be included in the request.  Inside the
   response to a 'retrieve' request, in case of responseCode of
   'success', the 'confInfo' containing a description of the target
   conference object MUST be included.  On the other hand, a response to
   a 'delete' operation SHOULD NOT include the 'confInfo' parameter.

   In case of an 'update' operation, the 'confInfo' and 'confObjID MUST
   be included in the request.  The 'confInfo' represents an object of
   type "conference-type" containing all the changes to be applied to
   the conference whose identifier is 'confObjId'.  In the case of a
   responseCode of success, no additional information is REQUIRED in the
   'confResponse'message.  For a successful response, the conference



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   server should consider as unchanged all parts of the referenced
   conference document.  However, if the target conference object has
   not been modified exactly as required by the client the responsecode
   MUST be set to 'modified' and the 'confInfo' parameter MUST contain
   the entire conference document to which the required changes have
   been (at least partially) applied.

   The schema for the confRequest/confResponse pair is shown in
   Figure 7.










































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   <!-- confRequest -->
   <xs:complexType name="ccmp-conf-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type">
                           <xs:sequence>
                                   <xs:element ref="confRequest" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- confRequestType -->

   <xs:element name="confRequest" type="confRequestType" />

     <xs:complexType name="confRequestType">
     <xs:sequence>
        <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
        <xs:element name="confInfo"
                    type="info:conference-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>

   <!-- confResponse -->
   <xs:complexType name="ccmp-conf-response-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-response-message-type">
                           <xs:sequence>
                                   <xs:element ref="confResponse" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- confResponseType -->

   <xs:element name="confResponse" type="confResponseType" />

   <xs:complexType name="confResponseType">
     <xs:sequence>
        <xs:element name="confInfo" type="info:conference-type"/>
     </xs:sequence>
   </xs:complexType>



     Figure 7: Structure of the confRequest and confResponse messages



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   The following provides an example of the 'confInfo' parameter
   required to change the title of a conference:



   <conf-info entity="123">
           <conference-description>
                   <display-text>New conference title</display-text>
           </conference-description>
   </conf-info>


     Figure 8: Updating a conference object: modifying the title of a
                                conference

   Similarly, to remove the title of an existing conference, an 'update'
   operation carrying the following 'confInfo' parameter would do the
   job.




   <conf-info entity="123">
           <conference-description>
                   <display-text/>
           </conference-description>
   </conf-info>


      Figure 9: Updating a conference object: removing the title of a
                                conference

7.2.3.5.  usersRequest and usersResponse messages

   Through a usersRequest message the CCMP client manipulates the
   <users> element of the conference document associated with the
   conference identified by the 'confObjId' parameter.  Inside the
   <users> element, along with the list of conference users, there is
   information that the client may be interested in controlling, such as
   the lists of users to which access to the conference is allowed/
   denied, conference participation policies, etc.; for this reason, a
   customized message has been designed to allow for the manipulation of
   this specific part of a conference document.  Besides the usual
   'operation' parameter, a 'usersInfo' parameter MAY also be included
   depending upon the operation.  The 'usersInfo' parameter carries an
   object compliant with the <users> field of the XCON data model.

   An 'operation' parameter MUST be included in a "usersRequest"



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   message.  Two operations are allowed in a "usersRequest" message:

   1.  retrieve: In this case the request SHOULD NOT include a
       'usersInfo' parameter, while a successful response MUST contain
       the desired <users> element in the 'usersInfo' parameter.

   2.  update: In this case, the 'usersInfo' parameter MUST contain the
       modifications to be applied to the referred <users> element.  If
       the responseCode is 'success', then the 'usersInfo' parameter
       SHOULD NOT be returned.  If the responseCode is 'modified', the
       'usersInfo' parameter MUST be included in the response.  The
       'usersInfo' reflects to the client the (partial) modifications
       that have been applied.

   Operations of 'create' and 'delete' make little sense in the case of
   a usersRequest and SHOULD NOT be considered by the server, which
   means that a responseCode of 'forbidden' SHOULD be included in the
   usersResponse message.

































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   <!-- usersRequest -->
   <xs:complexType name="ccmp-users-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type">
                           <xs:sequence>
                                   <xs:element ref="usersRequest" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- usersRequestType -->

   <xs:element name="usersRequest" type="usersRequestType" />

   <xs:complexType name="usersRequestType">
           <xs:sequence>
                   <xs:element name="operation" type="operationType"
                           minOccurs="1" maxOccurs="1" />
                   <xs:element name="usersInfo"
                   type="info:users-type" minOccurs="0" />
           </xs:sequence>
   </xs:complexType>

   <!-- usersResponse -->
   <xs:complexType name="ccmp-users-response-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-response-message-type">
                           <xs:sequence>
                                   <xs:element ref="usersResponse" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- usersResponseType -->

   <xs:element name="usersResponse" type="usersResponseType" />

   <xs:complexType name="usersResponseType">
     <xs:sequence>
        <xs:element name="usersInfo" type="info:users-type"/>
     </xs:sequence>
   </xs:complexType>



    Figure 10: Structure of the usersRequest and usersResponse messages



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7.2.3.6.  userRequest and userResponse messages

   A "userRequest" message is used to manipulate <user> elements inside
   a conference document associated with a conference identified by the
   'confObjId' parameter.  Besides retrieving information about a
   specific conference user, the message MAY be used to either create,
   or modify, or delete information about a user.  A "userRequest" MUST
   include the 'operation' parameter, and MAY include a 'userInfo'
   parameter containing the detailed user's information.

   Conference users can be created in a number of different ways.  Let
   us first consider the case of a user who wants to enter a conference
   (i.e. to add himself to the conference).  In such a case, the
   'userInfo' parameter in the request (which MUST have an 'operation'
   value set to "create") SHOULD contain a <user> element (compliant
   with the XCON data model) having its 'entity' attribute set to a
   value which represents the XCON-USERID of the user in question.

   A different situation is one in which the CCMP client acts on behalf
   of a third user, whose XCON-USERID is known.  In this case, the
   <user> element SHOULD contain an 'entity' attribute whose value is
   set to the XCON-USERID of the user in question.  As a final case, if
   the CCMP client is not aware of the XCON-USERID of the user to be
   inserted, the key attribute (i.e. 'entity') SHOULD NOT be included in
   the request: the XCON-USERID generated by the conference server for
   such a user MUST be returned to the client as the value of the
   'entity' attribute in the 'userInfo' parameter of the response if the
   responseCode is "success".  The last case also applies to a CCMP
   client that obtains a new user profile in the context of a
   conference.





















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   <!-- userRequest -->
   <xs:complexType name="ccmp-user-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type">
                           <xs:sequence>
                                   <xs:element ref="userRequest" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- userRequestType -->

   <xs:element name="userRequest" type="userRequestType" />

   <xs:complexType name="userRequestType">
           <xs:sequence>
                   <xs:element name="operation" type="operationType"
                           minOccurs="1" maxOccurs="1" />
                   <xs:element name="userInfo"
                   type="info:user-type" minOccurs="0" />
           </xs:sequence>
   </xs:complexType>


   <!-- userResponse -->
   <xs:complexType name="ccmp-user-response-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-response-message-type">
                           <xs:sequence>
                                   <xs:element ref="userResponse" />
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- userResponseType -->

   <xs:element name="userResponse" type="userResponseType" />

   <xs:complexType name="userResponseType">
     <xs:sequence>
        <xs:element name="userInfo" type="info:user-type"/>
     </xs:sequence>
   </xs:complexType>






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     Figure 11: Structure of the userRequest and userResponse messages

7.2.3.7.  sidebarsByValRequest and sidebarsByValResponse messages

   A "sidebarsByValRequest" is used to execute a retrieve-only operation
   on the <sidebars-by-val> field of the conference object represented
   by the 'confObjId'.  The request MUST include an 'operation' of
   "retrieve" and a 'confObjId'.  A "sidebarsByValResponse" MUST contain
   a 'sidebarsByValInfo' parameter reporting the desired <sidebars-by-
   val> element.  The 'sidebarsByValInfo' parameter contains the
   identifiers of the sidebars derived from the main conference.  For
   the creation and manipulation of sidebars, a different message has
   been envisaged, namely "sidebarByValRequest", which is described in
   Section 7.2.3.8



   <!-- sidebarsByValRequest -->

   <xs:complexType name="ccmp-sidebarsByVal-request-message-type">
           <xs:complexContent>
                   <xs:extension base="tns:ccmp-request-message-type">
                           <xs:sequence>
                      <xs:element ref="sidebarsByValRequest"/>
                           </xs:sequence>
                   </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- sidebarsByValRequestType -->

   <xs:element name="sidebarsByValRequest"
               type="sidebarsByValRequestType" />

   <xs:complexType name="sidebarsByValRequestType">
     <xs:sequence>
        <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
        <xs:element name="sidebarsByValInfo"
                    type="info:sidebars-by-val-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>


   <!-- sidebarsByValResponse -->

   <xs:complexType name="ccmp-sidebarsByVal-response-message-type">
           <xs:complexContent>



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            <xs:extension base="tns:ccmp-response-message-type">
                   <xs:sequence>
              <xs:element ref="sidebarsByValResponse"/>
             </xs:sequence>
            </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- sidebarsByValResponseType -->

   <xs:element name="sidebarsByValResponse"
               type="sidebarsByValResponseType" />

   <xs:complexType name="sidebarsByValResponseType">
     <xs:sequence>
        <xs:element name="sidebarsByValInfo"
                    type="info:sidebars-by-val-type"/>
     </xs:sequence>
   </xs:complexType>



           Figure 12: Structure of the sidebarsByValRequest and
                      sidebarsByValResponse messages

7.2.3.8.  sidebarByValRequest and sidebarByValResponse messages

   A "sidebarByValRequest" message MUST contain the 'operation'
   parameter which discriminates among creation, modification and
   deletion of a specific sidebar.  The 'sidebarByValInfo' parameter, in
   turn, contains the description (in an XCON data model compliant
   fashion) of the sidebar itself.  The 'confObjId' parameter of such
   messages MUST contain the XCON-URI of the main conference which the
   sidebar belongs to.  The XCON-URI of the sidebar is contained in the
   'entity' attribute of the above mentioned 'sidebarByValInfo'
   document.  In case of creation, the 'sidebarByValInfo' SHOULD NOT be
   included in the request, since, as envisaged in the XCON framework
   ([RFC5239]), sidebars are always created by cloning the main
   conference.  The 'sidebarByValInfo' parameter MUST be included in a
   successful response.  The 'sidebarByValInfo' represents the created
   sidebar, whose URI appears in the 'entity' attribute.



   <!-- sidebarByValRequest -->

   <xs:complexType name="ccmp-sidebarByVal-request-message-type">
           <xs:complexContent>



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            <xs:extension base="tns:ccmp-request-message-type">
                    <xs:sequence>
                           <xs:element ref="sidebarByValRequest"/>
                    </xs:sequence>
            </xs:extension>
     </xs:complexContent>
   </xs:complexType>

   <!-- sidebarByValRequestType -->

   <xs:element name="sidebarByValRequest"
               type="sidebarByValRequestType" />

   <xs:complexType name="sidebarByValRequestType">
    <xs:sequence>
      <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
      <xs:element name="sidebarByValInfo"
                    type="info:conference-type" minOccurs="0"/>
    </xs:sequence>
   </xs:complexType>


   <!-- sidebarByValResponse -->

   <xs:complexType name="ccmp-sidebarByVal-response-message-type">
    <xs:complexContent>
           <xs:extension base="tns:ccmp-response-message-type">
            <xs:sequence>
                   <xs:element ref="sidebarByValResponse"/>
            </xs:sequence>
     </xs:extension>
    </xs:complexContent>
   </xs:complexType>

   <!-- sidebarByValResponseType -->

   <xs:element name="sidebarByValResponse"
               type="sidebarByValResponseType" />

   <xs:complexType name="sidebarByValResponseType">
     <xs:sequence>
        <xs:element name="sidebarByValInfo"
                    type="info:conference-type"/>
     </xs:sequence>
   </xs:complexType>





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            Figure 13: Structure of the sidebarByValRequest and
                       sidebarByValResponse messages

7.2.3.9.  sidebarsByRefRequest and sidebarsByRefResponse messages

   Similar to the "sidebarsByValRequest", a "sidebarsByRefRequest" can
   be invoked to retrieve the <sidebars-by-ref> element of the
   conference object identified by the 'confObjId' parameter.  The
   'confObjID' parameter MUST be included in the request.  An operation
   of 'retrieve' MUST also be included in the request.  In the case of a
   responseCode of success, the 'sidebarsByRefInfo' parameter,
   containing the <sidebars-by-ref> element of the conference object,
   MUST be included in the response.  The <sidebars-by-ref> element
   represents the set of URIs of the sidebars associated with the main
   conference, whose description (in the form of a standard XCON
   conference document) is external to the main conference itself.
   Through the retrieved URIs, it is then possible to access single
   sidebars by exploiting the ad-hoc defined "sidebarByRef" request,
   described in Section 7.2.3.10.



   <!-- sidebarsByRefRequest -->
   <xs:complexType name="ccmp-sidebarsByRef-request-message-type">
           <xs:complexContent>
            <xs:extension base="tns:ccmp-request-message-type">
                   <xs:sequence>
                           <xs:element ref="sidebarsByRefRequest"/>
                   </xs:sequence>
            </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- sidebarsByRefRequestType -->

   <xs:element name="sidebarsByRefRequest"
               type="sidebarsByRefRequestType" />

   <xs:complexType name="sidebarsByRefRequestType">
     <xs:sequence>
        <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
        <xs:element name="sidebarsByRefInfo"
                    type="info:uris-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>





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   <!-- sidebarsByRefResponse -->

   <xs:complexType name="ccmp-sidebarsByref-response-message-type">
           <xs:complexContent>
            <xs:extension base="tns:ccmp-response-message-type">
                    <xs:sequence>
                           <xs:element ref="sidebarsByRefResponse"/>
                    </xs:sequence>
            </xs:extension>
     </xs:complexContent>
   </xs:complexType>

   <!-- sidebarsByRefResponseType -->

   <xs:element name="sidebarsByRefResponse"
               type="sidebarsByRefResponseType" />

   <xs:complexType name="sidebarsByRefResponseType">
     <xs:sequence>
        <xs:element name="sidebarsByRefInfo"
                    type="info:uris-type"/>
     </xs:sequence>
   </xs:complexType>



           Figure 14: Structure of the sidebarsByRefRequest and
                      sidebarsByRefResponse messages

7.2.3.10.  sidebarByRefRequest and sidebarByRefResponse messages

   A "sidebarByRefRequest" message along with the REQUIRED 'operation'
   parameter, MAY contain a 'sidebarByRefInfo' parameter describing the
   conference object (compliant with the XCON data model) associated
   with the sidebar.  In case of 'retrieve', 'delete', 'update' and
   'create' operations, the 'confObjId' parameter representing the XCON-
   URI of the target sidebar MUST be included.  The 'sidebarByRefInfo'
   parameter is NOT REQUIRED in the first two cases ('retrieve' and
   'delete'), whereas in the case of an 'update' the 'sidebarByRefInfo'
   parameter MUST contain the changes to be applied to the referenced
   sidebar.  The 'sidebarByRefInfo' MUST NOT be included for a 'create'
   operation since, as already stated, sidebar creation is by default
   achieved by cloning the main conference.




   <!-- sidebarByRefRequest -->



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   <xs:complexType name="ccmp-sidebarByRef-request-message-type">
     <xs:complexContent>
            <xs:extension base="tns:ccmp-request-message-type">
                   <xs:sequence>
                           <xs:element ref="sidebarByRefRequest"/>
                   </xs:sequence>
            </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- sidebarByRefRequestType -->

   <xs:element name="sidebarByRefRequest"
               type="sidebarByRefRequestType" />

   <xs:complexType name="sidebarByRefRequestType">
   <xs:sequence>
        <xs:element name="operation" type="operationType"
                    minOccurs="1" maxOccurs="1" />
        <xs:element name="sidebarByRefInfo"
                    type="info:conference-type" minOccurs="0"/>
     </xs:sequence>
   </xs:complexType>


   <!-- sidebarByRefResponse -->

   <xs:complexType name="ccmp-sidebarByref-response-message-type">
    <xs:complexContent>
            <xs:extension base="tns:ccmp-response-message-type">
                   <xs:sequence>
                    <xs:element ref="sidebarByRefResponse"/>
                   </xs:sequence>
            </xs:extension>
           </xs:complexContent>
   </xs:complexType>

   <!-- sidebarByRefResponseType -->

   <xs:element name="sidebarByRefResponse"
               type="sidebarByRefResponseType" />

   <xs:complexType name="sidebarByRefResponseType">
     <xs:sequence>
        <xs:element name="sidebarByRefInfo"
                    type="info:conference-type"/>
     </xs:sequence>
   </xs:complexType>



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            Figure 15: Structure of the sidebarByRefRequest and
                       sidebarByRefResponse messages

















































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8.  A complete example of the CCMP in action

   In this section a typical scenario in which the CCMP comes into play
   is described, by showing the actual composition of the various CCMP
   messages.  In the call flows of the example, the Conference Control
   Client is a CCMP-enabled client, whereas the Conference Control
   Server is a CCMP-enabled server.  The 'confUserId' of the client is
   "Alice" and appears in all requests.  The sequence of operations is
   as follows:

   1.  Alice retrieves from the server the list of available blueprints
       (Section 8.1);

   2.  Alice asks for detailed information about a specific blueprint
       (Section 8.2);

   3.  Alice decides to create a new conference by cloning the retrieved
       blueprint (Section 8.3);

   4.  Alice modifies information (e.g.  XCON-URI, name, description)
       associated with the newly created blueprint (Section 8.4);

   5.  Alice specifies a list of users to be contacted when the
       conference is activated (Section 8.5);

   6.  Alice joins the conference (Section 8.6);

   7.  Alice lets a new user (whose 'confUserId' is "Ciccio") join the
       conference (Section 8.7).

   Note, the examples do not include any details beyond the basic
   operation.

   In the following sections we deal with each of the above mentioned
   actions separately.

8.1.  Alice retrieves the available blueprints

   This section illustrates the transaction associated with retrieval of
   the blueprints, together with a dump of the two messages exchanged
   ("blueprintsRequest" and "blueprintsResponse").  As it comes out from
   the figure, the "blueprintsResponse" message contains, in the
   'blueprintsInfo' parameter, information about the available
   blueprints, in the form of the standard XCON-URI of the blueprint,
   plus additional (and optional) information, like its display-text and
   purpose.

   Alice retrieves from the server the list of available blueprints:



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     CCMP Client                                             CCMP Server
          |                                                       |
          | CCMP blueprintsRequest message                        |
          |   - confUserID: Alice                                 |
          |   - confObjId: (null)                                 |
          |------------------------------------------------------>|
          |                                                       |
          |                     CMP blueprintsResponse message    |
          |                      - confUserID: Alice              |
          |                      - confObjId: (null)              |
          |                      - responseCode: success          |
          |                      - blueprintsInfo: bp123,bp124,.. |
          |<------------------------------------------------------|
          |                                                       |
          .                                                       .
          .                                                       .

   1. blueprintsRequest message:

   <?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="xcon:ccmp-blueprints-request-message-type">
       <confUserID>Alice</confUserID>
    </ccmpRequest>
   </ccmp:ccmpRequest>

   2. blueprintsResponse message form the server:

   <?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>Alice</confUserID>
       <ccmp:response-code>success</ccmp:response-code>
        <ccmp:blueprintsResponse>
         <blueprintsInfo>
          <info:entry>
           <info:uri>xcon:AudioRoom@meetecho.com</info:uri>
           <info:display-text>AudioRoom</info:display-text>
           <info:purpose>Simple Room:
              conference room with public access,



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              where only audio is available, more users
              can talk at the same time
              and the requests for the AudioFloor
              are automatically accepted.
           </info:purpose>
          </info:entry>
          <info:entry>
           <info:uri>xcon:VideoRoom@meetecho.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,
               8 users can talk and be seen at the same time,
               and the floor requests are automatically accepted.
           </info:purpose>
          </info:entry>
          <info:entry>
           <info:uri>xcon:AudioConference1@meetecho.com</info:uri>
           <info:display-text>AudioConference1</info:display-text>
           <info:purpose>Public Audio Conference:
                conference with public access,
                where only audio is available,
                only one user can talk at the same time,
                and the requests for the AudioFloor MUST
                be accepted by a Chair.
           </info:purpose>
          </info:entry>
          <info:entry>
           <info:uri>xcon:VideoConference1@meetecho.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>
           <info:entry>
            <info:uri>xcon:AudioConference2@meetecho.com</info:uri>
            <info:display-text>AudioConference2</info:display-text>
            <info:purpose>Basic Audio Conference:
                 conference with private access,
                 where only audio is available,
                 only one user can talk at the same time,
                 and the requests for the AudioFloor MUST
                 be accepted by a Chair.
            </info:purpose>
           </info:entry>
        </blueprintsInfo>
      </ccmp:blueprintsResponse>



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     </ccmpResponse>
   </ccmp:ccmpResponse>



               Figure 16: Getting blueprints from the server

8.2.  Alice gets detailed information about a specific blueprint

   This section illustrates the second transaction in the overall flow.
   In this case, Alice, who now knows the XCON-URIs of the blueprints
   available at the server, makes a drill-down query, in the form of a
   CCMP "blueprintRequest" message, to get detailed information about
   one of them (the one called with XCON-URI
   "xcon:AudioRoom@meetecho.com").  The picture shows such transaction.
   Notice that the response contains, in the 'blueprintInfo' parameter,
   a document compliant with the standard XCON data model.

   Alice retrieves detailed information about a specified blueprint:




     CCMP Client                                             CCMP Server
          |                                                       |
          | CCMP blueprintRequest message                         |
          |   - confUserID: Alice                                 |
          |   - confObjId: bp123                                  |
          |   - Operation: retrieve                               |
          |   - blueprintInfo: (null)                             |
          |------------------------------------------------------>|
          |                                                       |
          |                        CCMP blueprintResponse message |
          |                          - confUserID: Alice          |
          |                          - confObjId: bp123           |
          |                          - responseCode: success      |
          |                          - blueprintInfo: bp123Info   |
          |<------------------------------------------------------|
          |                                                       |
          .                                                       .
          .                                                       .

   1. blueprintRequest message:

   <?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"



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         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">
           <confObjID>xcon:AudioRoom@meetecho.com</confObjID>
           <confUserID>Alice</confUserID>
           <ccmp:blueprintRequest>
               <operation>retrieve</operation>
           </ccmp:blueprintRequest>
     </ccmpRequest>
   </ccmp:ccmpRequest>

   2. blueprintResponse message form the server:

   <?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">
       <confObjID>xcon:AudioRoom@meetecho.com</confObjID>
       <confUserID>Alice</confUserID>
       <ccmp:response-code>success</ccmp:response-code>
       <ccmp:blueprintResponse>
         <blueprintInfo entity="AudioRoom">
           <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>
           </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>



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            Figure 17: Getting info about a specific blueprint

8.3.  Alice creates a new conference through a cloning operation

   This section illustrates the third transaction in the overall flow.
   Alice decides to create a new conference by cloning the blueprint
   having XCON-URI "xcon:AudioRoom@meetecho.com", for which she just
   retrieved detailed information through the "blueprintRequest"
   message.  This is achieved by sending a "confRequest/create" message
   having the blueprint's URI in the 'confObjId' parameter.  The picture
   shows such transaction.  Notice that the response contains, in the
   'confInfo' parameter, the document associated with the newly created
   conference, which is compliant with the standard XCON data model.
   The 'confObjId' in the response is set to the XCON-URI of the new
   conference (in this case, "xcon:8977794@meetecho.com").  We also
   notice that this value is equal to the value of the "entity"
   attribute of the <conference-info> element of the document
   representing the newly created conference object.

   Alice creates a new conference by cloning the
   "xcon:AudioRoom@meetecho.com" blueprint:




  CCMP Client                                             CCMP Server
         |                                                       |
         | CCMP confRequest message                              |
         |   - confUserID: Alice                                 |
         |   - confObjId: xcon:AudioRoom@meetecho.com            |
         |   - Operation: create                                 |
         |   - confInfo: (null)                                  |
         |------------------------------------------------------>|
         |                                                       |
         |                             CCMP confResponse message |
         |                               - confUserID: Alice     |
         |                               - confObjId: newConfId  |
         |                               - responseCode: success |
         |                               - confInfo: newConfInfo |
         |<------------------------------------------------------|
         |                                                       |
         .                                                       .
         .                                                       .

  1. confRequest message:

  <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <ccmp:ccmpRequest



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        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">
        <confObjID>xcon:AudioRoom@meetecho.com</confObjID>
        <confUserID>Alice</confUserID>
        <ccmp:confRequest>
            <operation>create</operation>
        </ccmp:confRequest>
     </ccmpRequest>
  </ccmp:ccmpRequest>


  2. confResponse message from the server:

  <?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">
       <confObjID>xcon:8977794@meetecho.com</confObjID>
       <confUserID>Alice</confUserID>
       <ccmp:response-code>success</ccmp:response-code>
       <ccmp:confResponse>
            <confInfo entity="xcon:8977794@meetecho.com">
              <info:conference-description>
                  <info:display-text>
                     New conference by Alice cloned from AudioRoom
                  </info:display-text>
                  <info:conf-uris>
                     <info:entry>
                        <info:uri>
                            xcon:8977794@meetecho.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>



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                   <info:available-media>
                          <info:entry label="11">
                              <info:type>audio</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="11"/>
                     </xcon:conference-floor-policy>
                  </xcon:floor-information>
              </confInfo>
          </ccmp:confResponse>
      </ccmpResponse>
  </ccmp:ccmpResponse>




        Figure 18: Creating a new conference by cloning a blueprint

8.4.  Alice updates conference information

   This section illustrates the fourth transaction in the overall flow.
   Alice decides to modify some of the details associated with the
   conference she just created.  More precisely, she changes the
   <display-text> element under the <conference-description> element of
   the document representing the conference.  This is achieved through a
   "confRequest/update" message carrying the fragment of the conference
   document to which the required changes have to be applied.  As shown
   in the picture, the response contains a code of 'success', which
   acknowledges the modifications requested by the client.

   Alice updates information about the conference she just created:




     CCMP Client                                             CCMP Server
          |                                                       |
          | CCMP confRequest message                              |
          |   - confUserID: Alice                                 |
          |   - confObjId: xcon:8977794@meetecho.com              |



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          |   - Operation: update                                 |
          |   - confInfo: conf456Updates                          |
          |------------------------------------------------------>|
          |                                                       |
          |                             CCMP confResponse message |
          |                               - confUserID: Alice     |
          |                               - confObjId: xcon:89..  |
          |                               - responseCode: success |
          |                               - confInfo: (null)      |
          |<------------------------------------------------------|
          |                                                       |
          .                                                       .
          .                                                       .


   1. confRequest message:

   <?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">
       <confObjID>xcon:8977794@meetecho.com</confObjID>
       <confUserID>Alice</confUserID>
       <ccmp:confRequest>
          <operation>update</operation>
            <confInfo entity="xcon:8977794@meetecho.com">
               <info:conference-description>
                 <info:display-text>
                    Alice's conference
                 </info:display-text>
               </info:conference-description>
            </confInfo>
         </ccmp:confRequest>
     </ccmpRequest>
   </ccmp:ccmpRequest>


   2. confResponse message form the server:

   <?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-conf-response-message-type">
        <confObjID>xcon:8977794@meetecho.com</confObjID>
        <confUserID>Alice</confUserID>
        <ccmp:response-code>success</ccmp:response-code>
        <ccmp:confResponse/>
     </ccmpResponse>
   </ccmp:ccmpResponse>



                Figure 19: Updating conference information

8.5.  Alice inserts a list of users in the conference object

   This section illustrates the fifth transaction in the overall flow.
   Alice modifies the <allowed-users-list> under the <users> element in
   the document associated with the conference she created.  To the
   purpose, she exploits the "usersRequest" message provided by the
   CCMP.  The picture below shows the transaction.

   Alice updates information about the list of users to whom access to
   the conference is permitted:



   CCMP Client                                             CCMP Server
        |                                                       |
        | CCMP usersRequest message                             |
        |   - confUserID: Alice                                 |
        |   - confObjId: xcon:8977794@meetecho.com              |
        |   - Operation: update                                 |
        |   - usersInfo: usersUpdates                               |
        |------------------------------------------------------>|
        |                                                       |
        |                            CCMP usersResponse message |
        |                              - confUserID: Alice      |
        |                              - confObjId: xcon:89..   |
        |                              - responseCode: success  |
        |                              - usersInfo: (null)      |
        |<------------------------------------------------------|
        |                                                       |
        .                                                       .
        .                                                       .

 1. usersRequest message:

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>



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 <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-users-request-message-type">
         <confObjID>xcon:8977794@meetecho.com</confObjID>
         <confUserID>Alice</confUserID>
         <ccmp:usersRequest>
           <operation>update</operation>
             <usersInfo>
                 <xcon:allowed-users-list>
                     <xcon:target method="dial out"
                                  uri="xmpp:cicciolo@pippozzo.com"/>
                     <xcon:target method="refer"
                                  uri="tel:+390817683823"/>
                     <xcon:target method="refer"
                                  uri="sip:Carol@example.com"/>
                 </xcon:allowed-users-list>
             </usersInfo>
         </ccmp:usersRequest>
     </ccmpRequest>
 </ccmp:ccmpRequest>


 2. usersResponse message form the server:

 <?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">
         <confObjID>xcon:8977794@meetecho.com</confObjID>
         <confUserID>Alice</confUserID>
         <ccmp:response-code>success</ccmp:response-code>
         <ccmp:confResponse/>
     </ccmpResponse>
 </ccmp:ccmpResponse>



     Figure 20: Updating the list of allowed users for the conference
                        'xcon:8977794@meetecho.com'






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8.6.  Alice joins the conference

   This section illustrates the sixth transaction in the overall flow.
   Alice uses the CCMP to add herself to the newly created conference.
   This is achieved through a "userRequest/create" message containing,
   in the 'userInfo' parameter, a <user> element compliant with the XCON
   data model representation.  Notice that such element includes
   information about the user's Address of Records, as well as her
   current end-point.  The picture below shows the transaction.  Notice
   how the 'confUserId' parameter is equal to the "entity" attribute of
   the <userInfo> element, which indicates that the request issued by
   the client is a first-party one.

   Alice joins the conference by issuing a "userRequest/create" message
   with her own id to the server:



    CCMP Client                                             CCMP Server
         |                                                       |
         | CCMP userRequest message                              |
         |   - confUserID: Alice                                 |
         |   - confObjId: xcon:8977794@meetecho.com              |
         |   - Operation: create                                 |
         |   - userInfo: AliceUserInfo                           |
         |------------------------------------------------------>|
         |                                                       |
         |                             CCMP userResponse message |
         |                               - confUserID: Alice     |
         |                               - confObjId: xcon:89..  |
         |                               - responseCode: success |
         |                               - userInfo: (null)      |
         |<------------------------------------------------------|
         |                                                       |
         .                                                       .
         .                                                       .

  1. userRequest message:

  <?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-confUser-request-message-type">
          <confObjID>xcon:8977794@meetecho.com</confObjID>
          <confUserID>Alice</confUserID>



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          <ccmp:confUserRequest>
              <operation>create</operation>
              <userInfo entity="Alice">
                  <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:confUserRequest>
      </ccmpRequest>
  </ccmp:ccmpRequest>


  2. userResponse message form the server:

  <?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-confUser-response-message-type">
          <confObjID>xcon:8977794@meetecho.com</confObjID>
          <confUserID>Alice</confUserID>
          <ccmp:response-code>success</ccmp:response-code>
          <ccmp:confUserResponse/>
      </ccmpResponse>
  </ccmp:ccmpResponse>



          Figure 21: Alice joins the conference through the CCMP

8.7.  Alice adds a new user to the conference

   This section illustrates the seventh and last transaction in the
   overall flow.  Alice uses the CCMP to add a new user to the
   conference.  This is achieved through a "userRequest/create" message
   containing, in the 'userInfo' parameter, a <user> element compliant
   with the XCON data model representation.  Notice that such element
   includes information about the user's Address of Records, as well as
   his current end-point.  The picture below shows the transaction.
   Notice how the 'confUserId' parameter in the request is Alice's id,



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   whereas the <userInfo> element has no "entity" attribute and contains
   information about a different user, thus indicating that the request
   issued by the client is a third-party one.  This is also reflected in
   the response coming from the server, which this time contains a non-
   void <userInfo> element, whose "entity" attribute has been set by the
   server to the value of the newly created conference user id.

   Alice adds user "Ciccio" to the conference by issuing a third-party
   "userRequest/create" message to the server:



   CCMP Client                                             CCMP Server
        |                                                       |
        | CCMP userRequest message                              |
        |   - confUserID: Alice                                 |
        |   - confObjId: xcon:8977794@meetecho.com              |
        |   - Operation: create                                 |
        |   - usersInfo: CiccioUserInfo                         |
        |------------------------------------------------------>|
        |                                                       |
        |                             CCMP userresponse message |
        |                               - confUserID: Alice     |
        |                               - confObjId: xcon:89..  |
        |                               - responseCode: success |
        |                               - usersInfo: (not null!)|
        |<------------------------------------------------------|
        |                                                       |
        .                                                       .
        .                                                       .

 1. "third party" userRequest message from Alice:

 <?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-confUser-request-message-type">
         <confObjID>xcon:8977794@meetecho.com</confObjID>
         <confUserID>Alice</confUserID>
         <ccmp:confUserRequest>
             <operation>create</operation>
             <userInfo>
                 <info:associated-aors>
                     <info:entry>
                         <info:uri>



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                             mailto:ciccio@pernacchio.com
                         </info:uri>
                         <info:display-text>email</info:display-text>
                     </info:entry>
                 </info:associated-aors>
                 <info:endpoint entity="sip:ciccio@pernacchio.com"/>
             </userInfo>
         </ccmp:confUserRequest>
     </ccmpRequest>
 </ccmp:ccmpRequest>


 2. "third party" userResponse message form the server:

 <?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-confUser-response-message-type">
         <confObjID>8977794</confObjID>
         <confUserID>Alice</confUserID>
         <ccmp:response-code>success</ccmp:response-code>
         <ccmp:confUserResponse>
             <confUserInfo entity="bn90ujbkj">
                 <info:associated-aors>
                     <info:entry>
                         <info:uri>
                            mailto:ciccio@pernacchio.com
                         </info:uri>
                         <info:display-text>email</info:display-text>
                     </info:entry>
                 </info:associated-aors>
                 <info:endpoint entity="sip:ciccio@pernacchio.com"/>
             </confUserInfo>
         </ccmp:confUserResponse>
     </ccmpResponse>
 </ccmp:ccmpResponse>



    Figure 22: Alice adds a new user to the conference through the CCMP








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9.  Locating a Conference Control Server

   If a conference control client is not pre-configured to use a
   specific conference control server for the requests, the client MUST
   first discover the conference control server before it can send any
   requests.  The result of the discovery process, is the address of the
   server supporting conferencing.  In this document, the result is an
   http: or https: URI, which identifies a conference server.

   This document proposes the use of DNS to locate the conferencing
   server.  U-NAPTR resolution for conferencing takes a domain name as
   input and produces a URI that identifies the conferencing server.
   This process also requires an Application Service tag and an
   Application Protocol tag, which differentiate conferencing-related
   NAPTR records from other records for that domain.

   Section 12.4.1 defines an Application Service tag of "XCON", which is
   used to identify the centralized conferencing (XCON) server for a
   particular domain.  The Application Protocol tag "CCMP", defined in
   Section 12.4.2, is used to identify an XCON server that understands
   the CCMP protocol.

   The NAPTR records in the following example Figure 23 demonstrate the
   use of the Application Service and Protocol tags.  Iterative NAPTR
   resolution is used to delegate responsibility for the conferencing
   service from "zonea.example.com." and "zoneb.example.com." to
   "outsource.example.com.".



             zonea.example.com.
             ;;       order pref flags
             IN NAPTR 100   10   ""  "XCON:CCMP" (     ; service
             ""                                        ; regex
             outsource.example.com.                    ; replacement
             )
             zoneb.example.com.
             ;;       order pref flags
             IN NAPTR 100   10   ""  "XCON:CCMP" (     ; service
             ""                                        ; regex
             outsource.example.com.                    ; replacement
             )
             outsource.example.com.
             ;;       order pref flags
             IN NAPTR 100   10   "u"  "XCON:CCMP" (    ; service
             "!*.!https://confs.example.com/!"         ; regex
             .                                         ; replacement
             )



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             Figure 23: Sample XCON:CCMP Service NAPTR Records

   Details for the "XCON" Application Service tag and the "CCMP"
   Application Protocol tag are included in Section 12.4.















































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10.  XML Schema

   This section provides the XML schema definition of the "application/
   ccmp+xml" format.



  <?xml version="1.0" encoding="utf-8"?>
     <xs:schema
         targetNamespace="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:tns="urn:ietf:params:xml:ns:xcon:ccmp"
         xmlns:dm="urn:ietf:params:xml:ns:xcon-conference-info"
         xmlns:info="urn:ietf:params:xml:ns:conference-info"
         xmlns:xs="http://www.w3.org/2001/XMLSchema">

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

         <xs:element name="ccmpRequest" type="ccmp-request-type" />
         <xs:element name="ccmpResponse" type="ccmp-response-type" />


          <!-- CCMP request definition -->

  <xs:complexType name="ccmp-request-type">
          <xs:sequence>
                  <xs:element name="ccmpRequest"
                            type="ccmp-request-message-type" />
          </xs:sequence>
  </xs:complexType>

          <!-- CCMP response definition -->

  <xs:complexType name="ccmp-response-type">
    <xs:sequence>
           <xs:element name="ccmpResponse"
                           type="ccmp-response-message-type" />
          </xs:sequence>
  </xs:complexType>

          <!--  Definition of ccmp-request-message-type -->




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  <xs:complexType abstract="true"
      name="ccmp-request-message-type">
     <xs:sequence>
       <xs:element name="confUserID" type="xs:string"
          minOccurs="1" maxOccurs="1" />
       <xs:element name="confObjID" type="xs:string"
          minOccurs="0" maxOccurs="1" />
     </xs:sequence>
  </xs:complexType>

    <!-- blueprintsRequest -->
  <xs:complexType name="ccmp-blueprints-request-message-type">
      <xs:complexContent>
        <xs:extension base="tns:ccmp-request-message-type"/>
      </xs:complexContent>
  </xs:complexType>

   <!--  blueprintRequest -->
  <xs:complexType name="ccmp-blueprint-request-message-type">
      <xs:complexContent>
        <xs:extension base="tns:ccmp-request-message-type">
          <xs:sequence>
                  <xs:element ref="blueprintRequest" />
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
  </xs:complexType>

  <!-- blueprintRequestType -->

  <xs:element name="blueprintRequest" type="blueprintRequestType" />

     <xs:complexType name="blueprintRequestType">
        <xs:sequence>
            <xs:element name="operation" type="operationType"
                        minOccurs="1" maxOccurs="1" />
            <xs:element name="blueprintInfo"
                   type="info:conference-type" minOccurs="0"/>
        </xs:sequence>
  </xs:complexType>

  <!-- confsRequest -->
  <xs:complexType name="ccmp-confs-request-message-type">
      <xs:complexContent>
        <xs:extension base="tns:ccmp-request-message-type"/>
      </xs:complexContent>
  </xs:complexType>




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  <!-- confRequest -->
  <xs:complexType name="ccmp-conf-request-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-request-message-type">
          <xs:sequence>
                  <xs:element ref="confRequest" />
          </xs:sequence>
         </xs:extension>
       </xs:complexContent>
  </xs:complexType>

  <!-- confRequestType -->

  <xs:element name="confRequest" type="confRequestType"/>

      <xs:complexType name="confRequestType">
        <xs:sequence>
            <xs:element name="operation" type="operationType"
                        minOccurs="1" maxOccurs="1" />
            <xs:element name="confInfo"
                type="info:conference-type" minOccurs="0"/>
        </xs:sequence>
       </xs:complexType>

  <!-- usersRequest -->
  <xs:complexType name="ccmp-users-request-message-type">
    <xs:complexContent>
      <xs:extension base="tns:ccmp-request-message-type">
        <xs:sequence>
          <xs:element ref="usersRequest"/>
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

          <!-- usersRequestType -->
  <xs:element name="usersRequest" type="usersRequestType"/>

    <xs:complexType name="usersRequestType">
                  <xs:sequence>
                   <xs:element name="operation" type="operationType"
                                          minOccurs="1" maxOccurs="1" />
                   <xs:element name="usersInfo"
              type="info:users-type" minOccurs="0" />
            </xs:sequence>
          </xs:complexType>

  <!-- userRequest -->



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  <xs:complexType name="ccmp-user-request-message-type">
    <xs:complexContent>
      <xs:extension base="tns:ccmp-request-message-type">
        <xs:sequence>
          <xs:element ref="userRequest" />
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- userRequestType -->

  <xs:element name="userRequest" type="userRequestType" />

  <xs:complexType name="userRequestType">
          <xs:sequence>
      <xs:element name="operation"
          type="operationType"
                            minOccurs="1" maxOccurs="1" />
            <xs:element name="userInfo"
          type="info:user-type"
          minOccurs="0" />
          </xs:sequence>
  </xs:complexType>

                  <!-- sidebarsByValRequest -->

  <xs:complexType name="ccmp-sidebarsByVal-request-message-type">
     <xs:complexContent>
       <xs:extension base="tns:ccmp-request-message-type">
        <xs:sequence>
          <xs:element ref="sidebarsByValRequest"/>
        </xs:sequence>
       </xs:extension>
     </xs:complexContent>
   </xs:complexType>

  <!-- sidebarsByValRequestType -->

  <xs:element name="sidebarsByValRequest"
              type="sidebarsByValRequestType" />

  <xs:complexType name="sidebarsByValRequestType">
       <xs:sequence>
          <xs:element name="operation" type="operationType"
                      minOccurs="1" maxOccurs="1" />
          <xs:element name="sidebarsByValInfo"
              type="info:sidebars-by-val-type" minOccurs="0"/>



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       </xs:sequence>
  </xs:complexType>


  <!-- sidebarsByRefRequest -->
     <xs:complexType name="ccmp-sidebarsByRef-request-message-type">
        <xs:complexContent>
         <xs:extension base="tns:ccmp-request-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarsByRefRequest" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

  <!-- sidebarsByRefRequestType -->

  <xs:element name="sidebarsByRefRequest"
              type="sidebarsByRefRequestType" />

    <xs:complexType name="sidebarsByRefRequestType">
         <xs:sequence>
            <xs:element name="operation" type="operationType"
                        minOccurs="1" maxOccurs="1" />
            <xs:element name="sidebarsByRefInfo"
               type="info:uris-type" minOccurs="0"/>
         </xs:sequence>
       </xs:complexType>

  <!-- sidebarByValRequest -->

  <xs:complexType name="ccmp-sidebarByVal-request-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-request-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarByValRequest" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

  <!-- sidebarByValRequestType -->

    <xs:element name="sidebarByValRequest"
                type="sidebarByValRequestType"/>

      <xs:complexType name="sidebarByValRequestType">
       <xs:sequence>



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          <xs:element name="operation" type="operationType"
              minOccurs="1" maxOccurs="1" />
          <xs:element name="sidebarByValInfo"
              type="info:conference-type" minOccurs="0"/>
       </xs:sequence>
      </xs:complexType>

  <!-- sidebarByRefRequest -->

     <xs:complexType name="ccmp-sidebarByRef-request-message-type">
       <xs:complexContent>
         <xs:extension base="tns:ccmp-request-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarByRefRequest" />
          </xs:sequence>
         </xs:extension>
        </xs:complexContent>
     </xs:complexType>

  <!-- sidebarByRefRequestType -->

   <xs:element name="sidebarByRefRequest"
       type="sidebarByRefRequestType" />

       <xs:complexType name="sidebarByRefRequestType">
         <xs:sequence>
            <xs:element name="operation" type="operationType"
                minOccurs="1" maxOccurs="1" />
            <xs:element name="sidebarByRefInfo"
                type="info:conference-type" minOccurs="0"/>
         </xs:sequence>
       </xs:complexType>

  <!--  Definition of ccmp-response-message-type -->

  <xs:complexType abstract="true"
      name="ccmp-response-message-type">
      <xs:sequence>
         <xs:element name="confUserID" type="xs:string"
          minOccurs="0" maxOccurs="1" />
         <xs:element name="confObjID" type="xs:string"
           minOccurs="0" maxOccurs="1" />
         <xs:element ref="response-code" minOccurs="1"
           maxOccurs="1" />
      </xs:sequence>
  </xs:complexType>

  <!-- blueprintsResponse -->



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  <xs:complexType name="ccmp-blueprints-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="blueprintsResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- blueprintsResponseType -->

  <xs:element name="blueprintsResponse" type="blueprintsResponseType" />

     <xs:complexType name="blueprintsResponseType">
         <xs:sequence>
            <xs:element name="blueprintsInfo"
                type="info:uris-type" minOccurs="0"/>
         </xs:sequence>
     </xs:complexType>

                  <!-- blueprintResponse -->
  <xs:complexType name="ccmp-blueprint-response-message-type">
    <xs:complexContent>
      <xs:extension base="tns:ccmp-response-message-type">
       <xs:sequence>
         <xs:element ref="blueprintResponse"/>
       </xs:sequence>
      </xs:extension>
   </xs:complexContent>
  </xs:complexType>

    <!-- blueprintResponseType -->

  <xs:element name="blueprintResponse" type="blueprintResponseType" />

      <xs:complexType name="blueprintResponseType">
         <xs:sequence>
            <xs:element name="blueprintInfo"
                        type="info:conference-type"/>
         </xs:sequence>
     </xs:complexType>

                  <!-- confsResponse -->
  <xs:complexType name="ccmp-confs-response-message-type">
    <xs:complexContent>
      <xs:extension base="tns:ccmp-response-message-type">
        <xs:sequence>



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                  <xs:element ref="confsResponse" />
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

          <!-- confsResponseType -->

  <xs:element name="confsResponse" type="confsResponseType" />

      <xs:complexType name="confsResponseType">
         <xs:sequence>
            <xs:element name="confsInfo"
                type="info:uris-type" minOccurs="0"/>
         </xs:sequence>
     </xs:complexType>

          <!-- confResponse -->
  <xs:complexType name="ccmp-conf-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="confResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- confResponseType -->

  <xs:element name="confResponse" type="confResponseType" />

      <xs:complexType name="confResponseType">
         <xs:sequence>
            <xs:element name="confInfo"
                type="info:conference-type"/>
         </xs:sequence>
      </xs:complexType>

          <!-- usersResponse -->
  <xs:complexType name="ccmp-users-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="usersResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>



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  </xs:complexType>

      <!-- usersResponseType -->

  <xs:element name="usersResponse" type="usersResponseType" />

     <xs:complexType name="usersResponseType">
        <xs:sequence>
             <xs:element name="usersInfo" type="info:users-type"/>
        </xs:sequence>
    </xs:complexType>


                  <!-- userResponse -->
  <xs:complexType name="ccmp-user-response-message-type">
          <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="userResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- userResponseType -->

  <xs:element name="userResponse" type="userResponseType" />

     <xs:complexType name="userResponseType">
        <xs:sequence>
           <xs:element name="userInfo" type="info:user-type"/>
        </xs:sequence>
     </xs:complexType>

                  <!-- sidebarsByValResponse -->

  <xs:complexType name="ccmp-sidebarsByVal-response-message-type">
     <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarsByValResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- sidebarsByValResponseType -->




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  <xs:element name="sidebarsByValResponse"
              type="sidebarsByValResponseType" />

     <xs:complexType name="sidebarsByValResponseType">
         <xs:sequence>
            <xs:element name="sidebarsByValInfo"
                   type="info:sidebars-by-val-type"/>
         </xs:sequence>
     </xs:complexType>

                  <!-- sidebarsByRefResponse -->

  <xs:complexType name="ccmp-sidebarsByref-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarsByRefResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- sidebarsByRefResponseType -->

  <xs:element name="sidebarsByRefResponse"
      type="sidebarsByRefResponseType" />

  <xs:complexType name="sidebarsByRefResponseType">
       <xs:sequence>
            <xs:element name="sidebarsByRefInfo"
                type="info:uris-type"/>
            </xs:sequence>
  </xs:complexType>

                  <!-- sidebarByValResponse -->

  <xs:complexType name="ccmp-sidebarByVal-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarByValResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
  </xs:complexType>

          <!-- sidebarByValResponseType -->




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  <xs:element name="sidebarByValResponse"
              type="sidebarByValResponseType" />

     <xs:complexType name="sidebarByValResponseType">
        <xs:sequence>
            <xs:element name="sidebarByValInfo"
                type="info:conference-type"/>
         </xs:sequence>
     </xs:complexType>

                  <!-- sidebarByRefResponse -->

  <xs:complexType name="ccmp-sidebarByref-response-message-type">
      <xs:complexContent>
         <xs:extension base="tns:ccmp-response-message-type">
          <xs:sequence>
                  <xs:element ref="sidebarByRefResponse" />
          </xs:sequence>
         </xs:extension>
      </xs:complexContent>
    </xs:complexType>

          <!-- sidebarByRefResponseType -->

  <xs:element name="sidebarByRefResponse"
              type="sidebarByRefResponseType" />

     <xs:complexType name="sidebarByRefResponseType">
         <xs:sequence>
            <xs:element name="sidebarByRefInfo"
                type="info:conference-type"/>
         </xs:sequence>
     </xs:complexType>

          <!-- response-code -->

  <xs:element name="response-code" type="response-codeType" />

          <xs:simpleType name="response-codeType">
            <xs:restriction base="xs:token">
              <xs:enumeration value="success"/>
              <xs:enumeration value="pending"/>
              <xs:enumeration value="modified"/>
              <xs:enumeration value="badRequest"/>
              <xs:enumeration value="unauthorized"/>
              <xs:enumeration value="forbidden"/>
              <xs:enumeration value="objectNotFound"/>
              <xs:enumeration value="forbiddenDeleteParent"/>



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              <xs:enumeration value="forbiddenChangeProtected"/>
              <xs:enumeration value="requestTimeout"/>
              <xs:enumeration value="serverInternalError"/>
              <xs:enumeration value="notImplemented"/>
            </xs:restriction>
          </xs:simpleType>

           <!-- operationType -->

          <xs:simpleType name="operationType">
            <xs:restriction base="xs:token">
              <xs:enumeration value="retrieve"/>
              <xs:enumeration value="create"/>
              <xs:enumeration value="update"/>
              <xs:enumeration value="delete"/>
            </xs:restriction>
          </xs:simpleType>
    </xs:schema>


                                 Figure 24






























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11.  Managing notifications

   This section is still "Under Construction" and currently contains
   some views on handling notifications.

   One proposal is to stick with SIP notification.  Another alternative,
   which is commonly done in other web-based systems, is a "call back",
   i.e., the CCMP client provides the conference server with an HTTP URL
   which is invoked when a change occurs.  This is apparently how most
   credit card shopping cards work, having implemented one.  This works
   well for our scenario since a CCMP "client" is likely to be a web
   server that provides the graphical HTML user interface and uses CCMP
   as the backend to talk to the conference server.  In that particular
   case, there doesn't seem to be a problem of having both models.  PC-
   based clients behind NATs would provide a SIP event URI, web servers
   would probably find the HTTP model much easier to program with.

   Another option being considered is BOSH
   (http://xmpp.org/extensions/xep-0124.html), which is basically an
   extension to XMPP designed with the following aim: "...a transport
   protocol that emulates a bidirectional stream between two entities
   (such as a client and a server) by efficiently using multiple
   synchronous HTTP request/response pairs without requiring the use of
   polling or asynchronous chunking."

   A final consideration (under discussion only) is basic XMPP.

























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12.  IANA Considerations

   This document registers a new XML namespace, a new XML schema, and
   the MIME type for the schema.  This document also registers the
   "XCON" Application Service tag and the "CCMP" Application Protocol
   tag.  This document also defines registries for the CCMP operation
   types and response codes.

12.1.  URN Sub-Namespace Registration

   This section registers a new XML namespace,
   ""urn:ietf:params:xml:ns:xcon:ccmp"".

      URI: "urn:ietf:params:xml:ns:xcon:ccmp"

      Registrant Contact: IETF, XCON working group, (xcon@ietf.org),
      Mary Barnes (mary.barnes@nortel.com).

      XML:


         BEGIN
           <?xml version="1.0"?>
           <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
           <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
             <head>
               <title>CCMP Messages</title>
             </head>
             <body>
               <h1>Namespace for CCMP Messages</h1>
               <h2>urn:ietf:params:xml:ns:xcon:ccmp</h2>
   [[NOTE TO IANA/RFC-EDITOR: Please update RFC URL and replace XXXX
       with the RFC number for this specification.]]
               <p>See <a href="[[RFC URL]]">RFCXXXX</a>.</p>
             </body>
           </html>
         END


12.2.  XML Schema Registration

   This section registers an XML schema as per the guidelines in
   [RFC3688].







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   URI:  urn:ietf:params:xml:schema:xcon:ccmp

   Registrant Contact:  IETF, XCON working group, (xcon@ietf.org), Mary
      Barnes (mary.barnes@nortel.com).

   Schema:  The XML for this schema can be found as the entirety of
      Section 10 of this document.

12.3.  MIME Media Type Registration for 'application/ccmp+xml'

   This section registers the "application/ccmp+xml" MIME type.

   To:  ietf-types@iana.org

   Subject:  Registration of MIME media type application/ccmp+xml

   MIME media type name:  application

   MIME subtype name:  ccmp+xml

   Required parameters:  (none)

   Optional parameters:  charset
      Indicates the character encoding of enclosed XML.  Default is
      UTF-8.

   Encoding considerations:  Uses XML, which can employ 8-bit
      characters, depending on the character encoding used.  See RFC
      3023 [RFC3023], section 3.2.

   Security considerations:  This content type is designed to carry
      protocol data related conference control.  Some of the data could
      be considered private and thus should be protected.

   Interoperability considerations:  This content type provides a basis
      for a protocol

   Published specification:  RFC XXXX [[NOTE TO IANA/RFC-EDITOR: Please
      replace XXXX with the RFC number for this specification.]]

   Applications which use this media type:  Centralized Conferencing
      control clients and servers.

   Additional Information:  Magic Number(s): (none)
      File extension(s): .xml
      Macintosh File Type Code(s): (none)





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   Person & email address to contact for further information:  Mary
      Barnes <mary.barnes@nortel.com>

   Intended usage:  LIMITED USE

   Author/Change controller:  The IETF

   Other information:  This media type is a specialization of
      application/xml [RFC3023], and many of the considerations
      described there also apply to application/ccmp+xml.

12.4.  DNS Registrations

   Section 12.4.1 defines an Application Service tag of "XCON", which is
   used to identify the centralized conferencing (XCON) server for a
   particular domain.  The Application Protocol tag "CCMP", defined in
   Section 12.4.2, is used to identify an XCON server that understands
   the CCMP protocol.

12.4.1.  Registration  of a Location Server Application Service Tag

   This section registers a new S-NAPTR/U-NAPTR Application Service tag
   for XCON, as mandated by [RFC3958].

   Application Service Tag: XCON

   Intended usage: Identifies a server that supports centralized
   conferencing.

   Defining publication: RFCXXXX

   Contact information: The authors of this document

   Author/Change controller: The IESG

12.4.2.  Registration of a Location Server Application Protocol Tag for
         HELD

   This section registers a new S-NAPTR/U-NAPTR Application Protocol tag
   for the CCMP protocol, as mandated by [RFC3958].

   Application Service Tag: CCMP

   Intended Usage: Identifies the Centralized Conferencing (XCON)
   Manipulation Protocol.

   Applicable Service Tag(s): XCON




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   Terminal NAPTR Record Type(s): U

   Defining Publication: RFCXXXX

   Contact Information: The authors of this document

   Author/Change Controller: The IESG

12.5.  CCMP Protocol Registry

   This document requests that the IANA create a new registry for the
   CCMP protocol including an initial registry for operation types and
   response codes.

12.5.1.  CCMP Message Types

   The CCMP messages are described in Section 7 and defined in the XML
   schema in Section 10.  The following summarizes the requested
   registry:

   Related Registry:   CCMP Message Types Registry

   Defining RFC:  RFC XXXX [NOTE TO IANA/RFC-EDITOR: Please replace XXXX
      with the RFC number for this specification.]

   Registration/Assignment Procedures:  New CCMP message types are
      allocated on a specification required basis.

   Registrant Contact:  IETF, XCON working group, (xcon@ietf.org), Mary
      Barnes (mary.barnes@nortel.com).

   This section pre-registers the following initial CCMP message types:

   blueprintsRequest:  Used by a conference control client to query a
      conferencing system for its capabilities, in terms of available
      conference blueprints.

   blueprintsResponse:  The optionsResponse returns a list of Blueprints
      supported by the specific conference server.

   confsRequest:  Used by a conference control client to query a
      conferencing system for its scheduled/active conferences.

   confsResponse:  The confsResponse returns the list of the currently
      activated/scheduled conferences at the server.






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   confRequest:  The confRequest is used to create a conference object
      and/or to request an operation on the conference object as a
      whole.

   confResponse:  The confResponse indicates the result of the operation
      on the conference object as a whole.

   userRequest:  The userRequest is used to request an operation on the
      "user" element in the conference object.

   userResponse:  The userResponse indicates the result of the requested
      operation on the "user" element in the conference object.

   usersRequest  This usersRequest is used to manipulate the "users"
      element in the conference object, including parameters such as the
      allowed-users-list, join-handling, etc.

   usersResponse:  This usersResponse indicates the result of the
      request to manipulate the "users" element in the conference
      object.

   sidebarRequest:  This sidebarRequest is used to retrieve the
      information related to a sidebar or to create, change or delete a
      specific sidebar.

   sidebarResponse:  This sidebarResponse indicates the result of the
      sidebarRequest.

12.5.2.  CCMP Response Codes

   The following summarizes the requested registry for CCMP Response
   codes:

   Related Registry:   CCMP Response Code Registry

   Defining RFC:  RFC XXXX [NOTE TO IANA/RFC-EDITOR: Please replace XXXX
      with the RFC number for this specification.]

   Registration/Assignment Procedures:  New response codes are allocated
      on a first-come/first-serve basis with specification required.

   Registrant Contact:  IETF, XCON working group, (xcon@ietf.org), Mary
      Barnes (mary.barnes@nortel.com).

   This section pre-registers the following thirteen initial response
   codes as described above in Section 7:





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   success:  This code indicates that the request was successfully
      processed.

   modified:  This code indicates that the object was created, but may
      differ from the request.

   badRequest:  This code indicates that the request was badly formed in
      some fashion.

   unauthorized:  This code indicates that the user was not authorized
      for the specific operation on the conference object.

   forbidden:  This code indicates that the specific operation is not
      valid for the target conference object.

   objectNotFound:  This code indicates that the specific conference
      object was not found.

   operationNotAllowed:  This code indicates that the specific operation
      is not allowed for the target conference object (e.g.., due to
      policies, etc.)

   deleteFailedParent:  This code indicates that the conferencing system
      cannot delete the specific conference object because it is a
      parent for another conference object.

   changeFailedProtected:  This code indicates that the target
      conference object cannot be changed (e.g., due to policies, roles,
      privileges, etc.).

   requestTimeout:  This code indicates that the request could not be
      processed within a reasonable time, with the time specific to a
      conferencing system implementation.

   serverInternalError:  This code indicates that the conferencing
      system experienced some sort of internal error.

   notImplemented:  This code indicates that the specific operation is
      not implemented on that conferencing system.












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13.  Security Considerations

   Access to conference control functionality needs to be tightly
   controlled to keep attackers from disrupting conferences, adding
   themselves to conferences or engaging in theft of services.  In the
   case of a RESTful implementation of the CCMP, implementors need to
   deploy standard HTTP authentication and authorization mechanisms.
   Since conference information may contain secrets such as participant
   lists and dial-in codes, all conference control information SHOULD be
   carried over TLS (HTTPS).









































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14.  Acknowledgments

   The authors appreciate the feedback provided by Dave Morgan, Pierre
   Tane, Lorenzo Miniero and Tobia Castaldi.  Special thanks go to
   Roberta Presta for her invaluable contribution to this document.
   Roberta has worked on the specification of the CCMP protocol at the
   University of Napoli for the preparation of her Master thesis.  She
   has also implemented the CCMP prototype used for the trials and from
   which the dumps provided in Section 8 have been extracted.










































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15.  Changes since last Version

   NOTE TO THE RFC-Editor: Please remove this section prior to
   publication as an RFC.

   The following summarizes the changes between the WG 01 and the 02:

   1.  Changed the basic approach from REST to HTTP as a transport.
       This impacted most of the document - i.e., a major rewrite - 02
       is closer to 00 than the 01.

   2.  Added full example based on prototype.

   The following summarizes the changes between the WG 00 and the 01:

   1.  Changed the basic approach from using SOAP to REST - the
       fundamentals are the same in terms of schema, basic operations.
       This impacted most sections, in particular introduction and
       motivation.

   2.  Added new request types - blueprintsRequest, blueprintRequest and
       confsRequest.  The first replaces the optionsRequest and the
       latter allows the client to get a list of all active conferences.

   3.  Merged all requests into the basic operations table.  Added
       summary of RESTful examples (referenced by the basic operations
       table.

   4.  Added examples showing RESTful approach - i.e., HTTP methods for
       message exchange.

   5.  Removed requestID from the schema (it should be handle by the
       transport - e.g., HTTP).  Updated schema (based on current
       prototype - it still needs another revision.

   6.  Added placeholders for Notifications and Role Based Access
       Control.

   7.  Added some text for discovery using DNS (including IANA
       registrations)

   8.  Updated References: updated XCON FW RFC, SOAP/W3C moved to
       informational section.








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16.  References

16.1.  Normative References

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

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              January 2004.

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

   [I-D.ietf-xcon-common-data-model]
              Novo, O., Camarillo, G., Morgan, D., Even, R., and J.
              Urpalainen, "Conference Information Data Model for
              Centralized Conferencing (XCON)",
              draft-ietf-xcon-common-data-model-12 (work in progress),
              October 2008.

16.2.  Informative References

   [REST]     Fielding, "Architectural Styles and the Design of Network-
              based Software Architectures", 2000.

   [RFC3023]  Murata, M., St. Laurent, S., and D. Kohn, "XML Media
              Types", RFC 3023, January 2001.

   [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.

   [RFC3880]  Lennox, J., Wu, X., and H. Schulzrinne, "Call Processing
              Language (CPL): A Language for User Control of Internet
              Telephony Services", RFC 3880, October 2004.

   [RFC3958]  Daigle, L. and A. Newton, "Domain-Based Application
              Service Location Using SRV RRs and the Dynamic Delegation
              Discovery Service (DDDS)", RFC 3958, January 2005.

   [RFC3966]  Schulzrinne, H., "The tel URI for Telephone Numbers",
              RFC 3966, December 2004.




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   [I-D.ietf-xcon-event-package]
              Camarillo, G., Srinivasan, S., Even, R., and J.
              Urpalainen, "Conference Event Package Data Format
              Extension for Centralized Conferencing  (XCON)",
              draft-ietf-xcon-event-package-01 (work in progress),
              September 2008.

   [I-D.royer-calsch-xcal]
              Royer, D., "iCalendar in XML Format (xCal-Basic)",
              draft-royer-calsch-xcal-03 (work in progress),
              October 2005.

   [W3C.REC-soap12-part1-20030624]
              Gudgin, M., Hadley, M., Mendelsohn, N., Nielsen, H., and
              J. Moreau, "SOAP Version 1.2 Part 1: Messaging Framework",
              World Wide Web Consortium FirstEdition REC-soap12-part1-
              20030624, June 2003,
              <http://www.w3.org/TR/2003/REC-soap12-part1-20030624>.

   [W3C.REC-soap12-part2-20030624]
              Mendelsohn, N., Nielsen, H., Hadley, M., Gudgin, M., and
              J. Moreau, "SOAP Version 1.2 Part 2: Adjuncts", World Wide
              Web Consortium FirstEdition REC-soap12-part2-20030624,
              June 2003,
              <http://www.w3.org/TR/2003/REC-soap12-part2-20030624>.


























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Appendix A.  Appendix A: Other protocol models and transports considered
             for CCMP

   The operations on the objects can be implemented in at least two
   different ways, namely as remote procedure calls - using SOAP as
   described in Appendix A.1 and by defining resources following a
   RESTful architecture Appendix A.2.

   In both approaches, servers will have to recreate their internal
   state representation of the object with each update request, checking
   parameters and triggering function invocations.  In the SOAP
   approach, it would be possible to describe a separate operation for
   each atomic element, but that would greatly increase the complexity
   of the protocol.  A coarser-grained approach to the CCMP does require
   that the server process XML elements in updates that have not changed
   and that there can be multiple changes in one update.

   For CCMP, the resource (REST) model might appear more attractive,
   since the conference operations fit the CRUD approach.

   Neither of these approaches were considered ideal as SOAP was not
   considered to be general purpose enough for use in a broad range of
   operational environments.  It is quite awkward to apply a RESTful
   approach since the CCMP requires a more complex request/response
   protocol in order to maintain the data both in the server and at the
   client.  This doesn't map very elegantly to the basic request/
   response model, whereby a response typically indicates whether the
   request was successful or not, rather than providing additional data
   to maintain the synchronization between the client and server data.
   In addition, the CCMP clients may also receive the data in
   Notifications.  While the notification method or protocol used by
   some conferencing clients can be independent of the CCMP, the same
   data in the server is used for both the CCMP and Notifications - this
   requires a server application above the transport layer (e.g., HTTP)
   for maintaining the data, which in the CCMP model is transparent to
   the transport protocol.

A.1.  Using SOAP for the CCMP

   A remote procedure call (RPC) mechanism for the CCMP could use SOAP
   (Simple Object Access Protocol[W3C.REC-soap12-part1-20030624][W3C.REC
   -soap12-part2-20030624]), where conferences and the other objects are
   modeled as services with associated operations.  Conferences and
   other objects are selected by their own local identifiers, such as
   email-like names for users.  This approach has the advantage that it
   can easily define atomic operations that have well-defined error
   conditions.




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   All SOAP operations would use a single HTTP verb.  While the RESTful
   approach requires the use of a URI for each object, SOAP can use any
   token.

A.2.  A RESTful approach for the CCMP

   Conference objects can also be modeled as resources identified by
   URIs, with the basic CRUD operations mapped to the HTTP methods POST/
   PUT for creating objects, GET for reading objects, PATCH/POST/PUT for
   changing objects and DELETE for deleting them.  Many of the objects,
   such as conferences, already have natural URIs.

   CCMP can be mapped into the CRUD (Create, Read, Update, Delete)
   design pattern.  The basic CRUD operations are used to manipulate
   conference objects, which are XML documents containing the
   information characterizing a specified conference instance, be it an
   active conference or a conference blueprint used by the conference
   server to create new conference instances through a simple clone
   operation.

   Following the CRUD approach, CCMP could use a general-purpose
   protocol such as HTTP [RFC2616] to transfer domain-specific XML-
   encoded data objects defined in the Conference Information Data Model
   for Centralized Conferencing [I-D.ietf-xcon-common-data-model].

   Following on the CRUD approach, CCMP could follow the well-known REST
   (REpresentational State Transfer) architectural style [REST].  The
   CCMP could map onto the REST philosophy, by specifying resource URIs,
   resource formats, methods supported at each URI and status codes that
   have to be returned when a certain method is invoked on a specific
   URI.  A REST-style approach must ensure sure that all operations can
   be mapped to HTTP operations.

   The following summarizes the specific HTTP method that could be used
   for each of the CCMP Requests:

   Retrieve: HTTP GET could be used on XCON-URIs, so that clients can
   obtain data about conference objects in the form of XML data model
   documents.

   Create: HTTP PUT could be used to create a new object as identified
   by the XCON-URI or XCON-USERID.

   Change: Either HTTP PATCH or HTTP POST could be used to change the
   conference object identified by the XCON-URI.

   Delete: HTTP DELETE could be used to delete conference objects and
   parameters within conference objects identified by the XCON-URI.



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Authors' Addresses

   Mary Barnes
   Nortel
   2201 Lakeside Blvd
   Richardson, TX

   Email: mary.barnes@nortel.com


   Chris Boulton
   NS-Technologies

   Email: chris@ns-technologies.com


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

   Email: spromano@unina.it


   Henning Schulzrinne
   Columbia University
   Department of Computer Science
   450 Computer Science Building
   New York, NY  10027

   Email: hgs+xcon@cs.columbia.edu



















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