1、 International Telecommunication Union ITU-T H.450.7TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (03/2013) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMSInfrastructure of audiovisual services Supplementary services for multimedia Message waiting indication supplementary service for ITU-T H.323 syst
2、ems Recommendation ITU-T H.450.7 ITU-T H-SERIES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS H.100H.199 INFRASTRUCTURE OF AUDIOVISUAL SERVICES General H.200H.219 Transmission multiplexing and synchronization H.220H.229 Systems aspects H.230H.239 Comm
3、unication procedures H.240H.259 Coding of moving video H.260H.279 Related systems aspects H.280H.299 Systems and terminal equipment for audiovisual services H.300H.349 Directory services architecture for audiovisual and multimedia services H.350H.359 Quality of service architecture for audiovisual a
4、nd multimedia services H.360H.369 Supplementary services for multimedia H.450H.499MOBILITY AND COLLABORATION PROCEDURES Overview of Mobility and Collaboration, definitions, protocols and procedures H.500H.509 Mobility for H-Series multimedia systems and services H.510H.519 Mobile multimedia collabor
5、ation applications and services H.520H.529 Security for mobile multimedia systems and services H.530H.539 Security for mobile multimedia collaboration applications and services H.540H.549 Mobility interworking procedures H.550H.559 Mobile multimedia collaboration inter-working procedures H.560H.569
6、BROADBAND, TRIPLE-PLAY AND ADVANCED MULTIMEDIA SERVICES Broadband multimedia services over VDSL H.610H.619 Advanced multimedia services and applications H.620H.629 Ubiquitous sensor network applications and Internet of Things H.640H.649 IPTV MULTIMEDIA SERVICES AND APPLICATIONS FOR IPTV General aspe
7、cts H.700H.719 IPTV terminal devices H.720H.729 IPTV middleware H.730H.739 IPTV application event handling H.740H.749 IPTV metadata H.750H.759 IPTV multimedia application frameworks H.760H.769 IPTV service discovery up to consumption H.770H.779 Digital Signage H.780H.789 For further details, please
8、refer to the list of ITU-T Recommendations. Rec. ITU-T H.450.7 (03/2013) i Recommendation ITU-T H.450.7 Message waiting indication supplementary service for ITU-T H.323 systems Summary Recommendation ITU-T H.450.7 specifies the procedures and signalling protocol for the supplementary service for mes
9、sage waiting indication (SS-MWI) in ITU-T H.323 (packet-based multimedia communication systems) networks. The SS-MWI enables a served user to be sent a message waiting indication (MWI) and also enables this MWI to be cancelled. The served user may also be permitted to interrogate a message centre fo
10、r any MWIs. The procedures and the signalling protocol of this Recommendation are derived from the SS-MWI as specified in ISO/IEC 15505 and ISO/IEC 15506. This Recommendation makes use of the “Generic functional protocol for the support of supplementary services in ITU-T H.323 systems“ as defined in
11、 Recommendation ITU-T H.450.1. This revision introduces editorial and technical changes, clarifications and corrections, in particular those indicated in the Implementers Guide for Recommendations of the ITU-T H.323 system (2011). History Edition Recommendation Approval Study Group 1.0 ITU-T H.450.7
12、 1999-05-27 16 2.0 ITU-T H.450.7 2013-03-16 16 ii Rec. ITU-T H.450.7 (03/2013) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardiz
13、ation Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which m
14、eets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these 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-T
15、s purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation i
16、s voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) 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“
17、 and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may
18、involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability 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
19、Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database a
20、t http:/www.itu.int/ITU-T/ipr/. ITU 2013 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T H.450.7 (03/2013) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Terms and definitions . 1 4 Abbreviat
21、ions and acronyms 2 5 Introduction 2 6 SS-MWI service description . 3 6.1 Description . 3 6.2 Normal procedures . 3 6.3 Exceptional procedures 4 7 Signalling protocol for the support of SS-MWI . 4 7.1 SS-MWI coding requirements 4 7.2 Definitions of the SS-MWI state 8 7.3 Timers . 8 7.4 SS-MWI signal
22、ling procedures 8 7.5 Gatekeeper interactions 14 7.6 Interactions between SS-MWI and other supplementary services . 14 7.7 SS-MWI security considerations 15 8 Signalling flows for SS-MWI . 15 8.1 Example message sequence for SS-MWI activation 15 8.2 Example message sequence for SS-MWI deactivation 1
23、6 8.3 Example message sequence for SS-MWI interrogation . 17 9 Specification and description language (SDL) diagrams . 17 9.1 SDL representation of SS-MWI at the message centre endpoint . 17 9.2 SDL representation of SS-MWI at the served user 21 Bibliography. 23 Rec. ITU-T H.450.7 (03/2013) 1 Recomm
24、endation ITU-T H.450.7 Message waiting indication supplementary service for ITU-T H.323 systems 1 Scope This Recommendation describes the supplementary service for message waiting indication (SS-MWI), which is applicable to ITU-T H.323 multimedia endpoints. The SS-MWI is based on the equivalent supp
25、lementary service for the private integrated services network (PISN) as specified in ISO/IEC 15505 and ISO/IEC 15506. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the t
26、ime of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below.
27、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, the status of a Recommendation. ITU-T H.225.0 Recommendation ITU-T H.225.0 (2009), Call signalling protocols and media strea
28、m packetization for packet-based multimedia communication systems. ITU-T H.235.5 Recommendation ITU-T H.235.5 (2005), ITU-T H.323 security: Framework for secure authentication in RAS using weak shared secrets. ITU-T H.245 Recommendation ITU-T H.245 (2011), Control protocol for multimedia communicati
29、on. ITU-T H.323 Recommendation ITU-T H.323 (2009), Packet-based multimedia communications systems. ITU-T H.450.1 Recommendation ITU-T H.450.1 (2011), Generic functional protocol for the support of supplementary services in ITU-T H.323 systems. ISO/IEC 15505 ISO/IEC 15505:1997, Information technology
30、, Telecommunications and information exchange between systems Private Integrated Services Network (PISN) Specification, functional model and information flows Message waiting indication supplementary service. ISO/IEC 15506 ISO/IEC 15506:1997, Information technology, Telecommunications and informatio
31、n exchange between systems Private Integrated Services Network (PISN) Inter-exchange signalling protocol Message waiting indication supplementary service. 3 Terms and definitions This Recommendation defines the following terms: 3.1 message centre: The entity that requests activation or deactivation
32、of the message waiting indication (MWI). When a callback request is issued using the mechanism provided by the MWI, the originating user acts as a message centre. 2 Rec. ITU-T H.450.7 (03/2013) 3.2 message centre endpoint: The endpoint that handles the ITU-T H.323 signalling on behalf of the message
33、 centre. For example, this may be the message centre itself if it is directly attached to the ITU-T H.323 network, it may be the originating users endpoint, or it may be a Gateway. 3.3 message waiting indication: An indication to the served user when messages are waiting for the served user. 3.4 ser
34、ved user: The user to whom the message waiting indication (MWI) is sent when initiated by the message centre. NOTE The indication may be a lamp, special tone, display, etc. This is outside the scope of this Recommendation. 4 Abbreviations and acronyms This Recommendation uses the following abbreviat
35、ions and acronyms: APDU Application Protocol Data Unit ASN.1 Abstract Syntax Notation One GK Gatekeeper MWI Message Waiting Indication NFE Network Facility Extension PISN Private Integrated Services Network RAS Registration, Admission and Status SDL Specification and Description Language SS-MWI Supp
36、lementary Service Message Waiting Indication UTC Coordinated Universal Time (also known as Greenwich Mean Time (GMT) 5 Introduction The message waiting indication supplementary service (SS-MWI) provides a general purpose mechanism by which a user can be advised that messages intended for that user a
37、re available. A variety of message types are supported, such as voice mail, fax and teletext. In one of its simplest forms, when a message is left for a user, a message centre sends a notification to the served user, where a message waiting lamp is lit. Additional information provided by the notific
38、ation mechanism allows the served user to know the number of messages that are waiting, the types of messages, the subjects of the messages, and the priority of the highest priority message. In an ITU-T H.323 environment, where endpoints may commonly be directly associated with general purpose compu
39、ters, applications such as automated message retrieval may be envisioned. SS-MWI also provides a mechanism whereby it is possible for an endpoint to issue a callback request to the served user. The interrogation mechanism provided by the SS-MWI allows a served user to query message centres known to
40、it, or a known Gatekeeper (GK)/proxy for the MWI activations currently applied to it. A typical usage of this mechanism is by a served user to recreate its MWI status when the endpoint is returned to service, as the status may have changed while it was out of service. Rec. ITU-T H.450.7 (03/2013) 3
41、6 SS-MWI service description 6.1 Description The SS-MWI enables a served user to be sent an MWI and also enables this MWI to be cancelled. An MWI activation may also be used to send a callback request to the served user. This service also includes an option to interrogate the MWI stored against the
42、served user. A served user can receive separate MWIs for each of the basic services for which there is a message waiting. NOTE A basic service for which there is a message waiting would usually be the basic service used to retrieve that message. 6.2 Normal procedures 6.2.1 Activation, deactivation a
43、nd interrogation To activate SS-MWI, the message centre shall supply the endpoint address and the basic service for which there is a message waiting and may, as an implementation option, add any combination of the following pieces of information: the identity of the message centre; the number of mes
44、sages waiting for the served user for that basic service; the address of the user that left a message; the time when a message was left; and the priority of the highest priority message waiting for that basic service. After activation, the SS-MWI may be activated again whenever the number of waiting
45、 messages for a specific basic service changes. It is also possible to use SS-MWI activation to request that the served user initiate a call (callback) to a specified endpoint. To deactivate the SS-MWI, the message centre shall supply the endpoint address and the basic service for which there are no
46、 longer any messages waiting. As a result of activation, an MWI shall be sent to the served user. The MWI may include information on the messages waiting, if provided by the message centre. As a result of deactivation, the MWI at the served user, for the basic service concerned, shall be cancelled.
47、When the message centre activates or deactivates SS-MWI at the served user, it shall be provided with an indication of acceptance. When the served user interrogates the SS-MWI for a particular basic service, the message centre shall provide the served user with an indication of whether the SS-MWI is
48、 activated for that basic service and may add, as an implementation option, any of the following information: the identity of the message centre; the number of messages waiting; the address of the user that left a message; the time when a message was left; the priority of the highest priority messag
49、e waiting. When the served user interrogates the SS-MWI for all basic services, the message centre shall provide the served user with a list of basic services for which the SS-MWI is active and, as an implementation option, for each basic service, any of the additional information listed above. 6.2.2 Invocation and operation Not applicable. 4 Rec. ITU-T H.450.7 (03/2013) 6.3 Exceptional procedures 6.3.1 Activation, deactivation and interrogation If the served user cannot accept SS-MWI activation or
