1、 International Telecommunication Union ITU-T F.733TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2005) SERIES F: NON-TELEPHONE TELECOMMUNICATION SERVICES Audiovisual services Service description and requirements for multimedia conference services over IP networks ITU-T Recommendation F.733 ITU-
2、T F-SERIES RECOMMENDATIONS NON-TELEPHONE TELECOMMUNICATION SERVICES TELEGRAPH SERVICE Operating methods for the international public telegram service F.1F.19 The gentex network F.20F.29 Message switching F.30F.39 The international telemessage service F.40F.58 The international telex service F.59F.89
3、 Statistics and publications on international telegraph services F.90F.99 Scheduled and leased communication services F.100F.104 Phototelegraph service F.105F.109 MOBILE SERVICE Mobile services and multidestination satellite services F.110F.159 TELEMATIC SERVICES Public facsimile service F.160F.199
4、Teletex service F.200F.299 Videotex service F.300F.349 General provisions for telematic services F.350F.399 MESSAGE HANDLING SERVICES F.400F.499DIRECTORY SERVICES F.500F.549 DOCUMENT COMMUNICATION Document communication F.550F.579 Programming communication interfaces F.580F.599 DATA TRANSMISSION SER
5、VICES F.600F.699 AUDIOVISUAL SERVICES F.700F.799 ISDN SERVICES F.800F.849 UNIVERSAL PERSONAL TELECOMMUNICATION F.850F.899 HUMAN FACTORS F.900F.999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. F.733 (09/2005) i ITU-T Recommendation F.733 Service description and r
6、equirements for multimedia conference services over IP networks Summary The purpose of this Recommendation is to define the multimedia conference services based on IP networks. The service provides real-time communication between several users in different locations over an IP network. The service d
7、escription, functional model, application scenarios and requirements of the IP multimedia conference services are provided. The IP multimedia conference service is one class of the generic services identified in ITU-T Rec. F.702, and its description follows the methodology described in ITU-T Rec. F.
8、701. The requirements for the IP multimedia conference services are derived from the scenarios for different applications the said services can support. Therefore, the services requirements accommodate the demands of different kinds of users and assist in enabling intercommunications between the ser
9、vices systems provided by different telecom operators, or between the equipment manufactured by different manufacturers. Source ITU-T Recommendation F.733 was approved on 13 September 2005 by ITU-T Study Group 16 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. F.733 (09/2005)
10、 FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and
11、 issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on thes
12、e topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expre
13、ssion “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicabili
14、ty) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Rec
15、ommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability
16、of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this
17、 Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2005 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written
18、 permission of ITU. ITU-T Rec. F.733 (09/2005) iii CONTENTS Page 1 Scope 1 2 References. 1 2.1 Normative references 1 2.2 Informative references 1 3 Definitions 1 4 Convention 2 5 Prose description. 2 6 Application functional model . 3 6.1 Functional model 3 6.2 Multimedia conference mode . 4 6.3 Us
19、er roles 4 7 Scenarios. 5 7.1 Multimedia interactive conference. 5 7.2 Multicast conference 7 7.3 Mixed mode conference . 7 8 Requirements of IP multimedia conference . 8 8.1 User requirements. 8 8.2 Application requirements . 9 8.3 Numbering requirements 9 8.4 Security requirements. 9 8.5 Authentic
20、ation and accounting requirements . 10 8.6 QoS requirements . 10 9 Interworking and intercommunication . 10 9.1 Terminals with different capabilities 10 9.2 Terminals in different networks . 10 9.3 Different IP multimedia conference systems . 11 ITU-T Rec. F.733 (09/2005) 1 ITU-T Recommendation F.73
21、3 Service description and requirements for multimedia conference services over IP networks 1 Scope This Recommendation describes the multimedia conference service system over IP networks, its application scenarios and service requirements. 2 References The following ITU-T Recommendations and other r
22、eferences contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to
23、investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, th
24、e status of a Recommendation. 2.1 Normative references None. 2.2 Informative references ITU-T Recommendation F.700 (2000), Framework Recommendation for multimedia services. ITU-T Recommendation F.701 (2000), Guideline Recommendation for identifying multimedia service requirements. ITU-T Recommendati
25、on F.702 (1996), Multimedia conference services. ITU-T H-Series Recommendations Supplement 1 (1999), Application profile Sign language and lip-reading real-time conversation using low bit-rate video communication. 3 Definitions This Recommendation defines the following terms: 3.1 chairman: the user
26、who chairs the meeting and manages the conference. 3.2 communication mode: a communication mode is defined by the various channels supporting the media used for the conference. Changes in communication mode may occur during the course of the conference, in order to set up or eliminate one of the med
27、ia, or to change its quality level and thus the bit-rate allocation. The mode change may be used for instance to temporarily add a channel for transmitting still pictures. 3.3 conference convener: The user who has organized the conference. 3.4 centralized multipoint conference: A centralized multipo
28、int conference is one in which all participating terminals communicate in a point-to-point fashion with special control or processing facilities. 3.5 decentralized multipoint conference: A decentralized multipoint conference is one in which the participating terminals multicast their audio, video an
29、d text to all other participating terminals. 2 ITU-T Rec. F.733 (09/2005) 3.6 IP multimedia conference service: A type of multimedia conference service based on IP network that utilizes networks for control and media transfer. 3.7 multicast conference: A multicast conference is one in which there is
30、 one transmitter of media streams and many receivers. There is no bidirectional transmission of control or media streams. Such conferences may be implemented using network transport multicast facilities, if available. 3.8 multipoint interactive conference: A multipoint interactive conference is one
31、in which all participants are transmitters and receivers. There is bidirectional transmission of control or media streams. Such conferences should be implemented using special control or processing facilities, if available. 3.9 multimedia conference service: A multimedia conference service provides
32、real-time transmission of voice together with motion video, real time text and/or various types of multimedia information between groups of users in two or more locations. 3.10 muting: Preventing sound to be transmitted from a terminal equipment. 3.11 presenter: The participant in a conference who c
33、ontrols the visual information being actively discussed. 4 Convention In this Recommendation the following conventions are used: “shall“ indicates a mandatory requirement. “should“ indicates a suggested but optional course of action. “may“ indicates an optional course of action rather than a recomme
34、ndation that something take place. 5 Prose description An IP multimedia conference system provides real-time communication between several users in different locations, combining the audio, video and real-time text information of the participants, and other multimedia information if needed. The serv
35、ice can be bidirectional, and provide for interconnection of two or more multimedia conference terminals on an equal basis; it can also be unidirectional, where part of the terminals can only receive, while others can only send. If there are two or more terminals in the conference, equipment that ca
36、n provide multimedia information control and exchange is needed. Network side equipment that can manage and control the conference, and provide authentication and billing is also necessary. The multimedia conference services may be provided after prior arrangement with a service provider, or they ma
37、y be generally available. The conference connection can be established by a user or by a management system. The location of a multimedia conference participant could be anywhere where the network is accessible, e.g., meeting room, office, home, or even on the highway. The participants take part in t
38、he meeting by means of a multimedia conference terminal. The terminals may access the network by wire or wireless means. There are three types of terminal: Hardware-based terminals, which include two sub-types of terminal: a) Special conference terminals for studios dedicated to and equipped for mul
39、timedia conferences; b) Portable terminals which are only used on a part-time basis for teleconferencing and which can be moved from one place to another. ITU-T Rec. F.733 (09/2005) 3 Software-based terminals running on computers. Other types of terminals, e.g., POTS terminals, could also be used in
40、 the conference. Although there are certain limitations regarding their capability to send and receive different types of information used in a multimedia conference call, they are at least able to exchange speech, allowing their users to take part in the discussion. 6 Application functional model 6
41、.1 Functional model Figure 1/F.733 The multimedia conference functional model The IP multimedia conference functional model is shown in Figure 1. Multimedia conference terminals can access IP-based networks with several kinds of modes, e.g., LAN, WLAN, xDSL, PLMN, and PSTN. Network functions above t
42、he dashed line constitute an IP multimedia conference service platform directly related with users: a) Conference Management and Control Function: it can initiate an immediate conference according to the users demand, or accept the users conference reservation and allocate the system resource. b) Mu
43、ltimedia Switch and Process Function: it provides control functions to the conference, switches and processes the audio, video and text, and/or data streams. c) Interworking function: other multimedia conference terminals can access the IP multimedia conference network via the interworking function.
44、 d) Authentication, Authorization and Accounting (AAA): it provides the Conference Management and Control Function with the users identification information, and processes accounting information from the Conference Management and Control Function. 4 ITU-T Rec. F.733 (09/2005) 6.2 Multimedia conferen
45、ce mode Two types of basic multimedia conferences service modes are addressed in this Recommendation. Other types are left to the creativity of the service providers and equipment manufacturers. a) Multipoint interactive conference mode In this mode, all participating terminals communicate in a poin
46、t-to-point fashion, possibly with the involvement of the Multimedia Switch b) Cancelling/modifying the reservation; c) Initiating a conference on demand; d) Terminating the conference; e) Inviting a new participant; f) Accepting a new participant; g) Disconnecting a participant from the conference.
47、Controllers advanced1functions include: a) Splitting the conference; b) Extending the conference. During a conference, a participant can apply to be chairman. A chairman is responsible for its management. Basic functions are: a) Managing the conference; b) Displaying him or herself, or one of the ot
48、her participants, on the terminal screens. The chairmans advanced functions include: a) Giving the floor to a participant; b) Ensuring the conference terminals broadcast in turn; c) Muting another terminal; d) Organizing or allowing a private conversation; _ 1In this Recommendation, “basic“ refers t
49、o a mandatory requirement, while “advanced“ refers to a suggested but optional feature or procedure. ITU-T Rec. F.733 (09/2005) 5 e) Controlling data transfer; f) Controlling remote equipment. The conference participants basic functions include: a) Participation in the conference; b) Muting local microphones. The conference participants advanced functions include: a) Requesting to be nominated as chairman; b) Requesting the floor; c) Receiving certain indicative information, such as site and time; d) Initiating a data
