1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU H.248.13 (03/2 002) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMS Infrastructure of audiovisual services - Communication procedures Gateway control protocol: Quality Alert Ceasing package ITU-T Recommendation
2、H.248.13 ITU-T H-SERIES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS INFRASTRUCTURE OF AUDIOVISUAL SERVICES General Transmission multiplexing and synchronization H.100-H.199 H.200-H.2 19 H.220-H.229 II Svstems asnects 11 Communiktion procedures II Co
3、ding of moving video H.230-H.239 H.260-H.279 _* 25 Related systems aspects SYSTEMS AND TERMINAL EQUIPMENT FOR AUDIOVISUAL SERVICES SUPPLEMENTARY SERVICES FOR MULTIMEDIA MOBILITY AND COLLABORATION PROCEDURES Overview of Mobility and Collaboration, definitions, protocols and procedures Mobility for H-
4、Series multimedia systems and services Mobile multimedia collaboration applications and services Security for mobile multimedia systems and services Security for mobile multimedia collaboration applications and services Mobility interworking procedures Mobile multimedia collaboration inter-working p
5、rocedures H.280-H.299 H.300-H.399 H.450-H.499 H.500-H.509 H.510-H.519 H.530-H.539 H.540-H.549 H.550-H.559 H.560-H.569 H.520-H.529 For further details, please refer to the list of ITU-T Recommendations. ITU-T Recommendation H.248.13 Gateway control protocol: Quality Alert Ceasing package Summary This
6、 Recommendation specifies an event used by a media gateway to indicate to the media gateway controller that a Quality Alert on a bearer has ceased. NOTE - This Recommendation has been renumbered. It was formerly known as ITU-T Rec. H.248, Annex M5. Source ITU-T Recommendation H.248.13 was prepared b
7、y ITU-T Study Group 16 (200 1-2004) and approved under the WTSA Resolution 1 procedure on 29 March 2002. ITU-T Rec. H.248.13 (0312002) i FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Sta
8、ndardization 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),
9、which meets , 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 wit
10、hin ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS
11、 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 of claimed Intellectual Property Rights, whether asserted by ITU m
12、embers 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 Recommendation. However, implementors are cautioned that this may
13、 not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 2002 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ii ITU-T Rec. H.248.13 (03/2002) CONTENTS 1
14、Scope . 2 References . 3 Definitions 4 Abbreviations 5 Quality Alert Ceasing package . 5.1 Properties 5.2 Events . 5.2.1 Event name: Quality Alert Ceasing 5.3 Signals 5.4 Statistics 5.5 Procedures 1 1 1 1 1 1 2 2 2 2 2 ITU-T Rec . H.248.13 (03/2002) iii ITU-T Recommendation H.248.13 Gateway control
15、protocol: Quality Alert Ceasing package 1 Scope This Recommendation specifies an event used by a media gateway to indicate to the media gateway controller that a Quality Alert on a bearer has ceased. The package defined in this Recommendation extends a previously defined package. It contains an even
16、t to indicate Quality Alert Ceasing on a particular bearer. 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 time of publication, the editions indicated were valid. All
17、 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. A list of the currently valid ITU-T Recommendations is reg
18、ularly published. - ITU-T Recommendation H.248.1 (2002), Gateway Control Protocol. 3 Definitions See ITU-T Rec. H.248.1. 4 Abbreviations This Recommendation uses the following abbreviations: MG Media Gateway MGC Media Gateway Controller 5 Quality Alert Ceasing package PackageID: qac, 0x0037 Descript
19、ion: Version: 1 Extends: nt (Ox000b) version1 This package defines the Quality Alert Ceasing event, complementing the existing Quality Alert event defined within the Network Package E. 1 lH.248.1. 5.1 Properties None. ITU-T Rec. H.248.13 (03/2002) 1 5.2 Events 5.2.1 EventID: qualertcease, 0x0004 Des
20、cription: Event name: Quality Alert Ceasing The termination generates this event upon detection of ceasing loss of quality alerts and a return to acceptable quality on the network connection. EventsDescriptor Parameters: Threshold ParameterId: th (0x0001) optional Description: This parameter specifi
21、es the alert threshold level where the MG shall consider that the quality of the stream is at an acceptable level. Type: integer Possible Values: threshold for percent of quality loss measured, calculated based on a provisioned method, that could take into consideration packet loss, jitter, and dela
22、y for example. ObservedEventsDescriptor Parameters: None. 5.3 Signals None. 5.4 Statistics None. 5.5 Procedures The quality alert ceasing package builds on the existing quality alert event specified in the network package. The additional event specified in this package provides a mechanism to report
23、 when a specific network condition ceases. The MGC shall set this event on the termination of the bearer that it is interested in monitoring the quality on. The MG shall send this event in the case that: o it had previously notified the MGC of a Network Package Quality Alert event; and the quality o
24、f the bearer is now at an acceptable level, or less than the threshold level o parameter if set with the qualertcease event and no quality alerts are outstanding. Figure 1 shows example quality alert procedures. The quality alert and alert ceasing events may also be contained in an Add.req or before
25、 the bearer is established. 2 ITU-T Rec. H.248.13 (03/2002) MGC Notify.reply Noti.ind(Event(QuaiertThreshold i) Notify.reply Notify.ind(Event(Quaiertcease) Notifyxeply b 4 b 4 b I I QosLoss is better than 2 but e- stiiiexceed i Qos Loss is better han 1 and - + at a nomai levei. Mod/Mov.req Bearer Es
26、tablished (Ce1 , Tid=b, Event( QuaiertThresholdl J, QuaiertThreshold2, QuaiertThreshold3, Quaiertcease) ModMov.reply Ctxt=l , Tid=b) I I l Qos Loss ExcecdThreshold 1 Notify.ind(Event(QudetThresholdl) 4 Notify.reply I I Qos Loss Exceed Threshold 2 Notify.ind(Event(QuaiertThreshold2) 4 TI 61 0333-02 F
27、igure lH.248.13 - Quality Alert Ceasing procedures ITU-T Rec. H.248.13 (03/2002) 3 SERIES OF ITU-T RECOMMENDATIONS Series A Series B Series C Series D Series E Series F Series G Series H Series I Series J Series K Series L Series M Series N Series O Series P Series Q Series R Series S Series T Serie
28、s U Series V Series X Series Y Series Z Organization of the work of ITU-T Means of expression: definitions, symbols, classification General telecommunication statistics General tariff principles Overall network operation, telephone service, service operation and human factors Non-telephone telecommu
29、nication services Transmission systems and media, digital systems and networks Audiovisual and multimedia systems Integrated services digital network Cable networks and transmission of television, sound programme and other multimedia signals Protection against interference Construction, installation
30、 and protection of cables and other elements of outside plant TMN and network maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and leased circuits Maintenance: international sound programme and television transmission circuits Specifications of measuring equ
31、ipment Telephone transmission quality, telephone installations, local line networks Switching and signalling Telegraph transmission Telegraph services terminal equipment Terminals for telematic services Telegraph switching Data communication over the telephone network Data networks and open system communications Global information infrastructure and Internet protocol aspects Languages and general software aspects for telecommunication systems *22163* Printed in Switzerland Geneva, 2002
