1、 International Telecommunication Union ITU-T G.1081TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (10/2008) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Multimedia Quality of Service and performance Generic and user-related aspects Performance monitoring points for IPTV Re
2、commendation ITU-T G.1081 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTER
3、NATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND
4、OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.699
5、9 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.1081 (10/2008) i Recommendation ITU-T G.1081 Performance monitoring points for IPTV Summary S
6、uccessful deployment of IPTV services requires performance parameters to be monitored at a number of different points in the complete end-to-end chain, including the customer premises, key aggregation points and at interconnect points between disparate and service provider network domains. Recommend
7、ation ITU-T G.1081 defines five monitoring points where such performance measurements can be made. Source Recommendation ITU-T G.1081 was approved on 22 October 2008 by ITU-T Study Group 12 (2005-2008) under Recommendation ITU-T A.8 procedure. Keywords IPTV, monitoring points, performance, QoE, QoS.
8、 ii Rec. ITU-T G.1081 (10/2008) 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 Standardization Sector (ITU-T) is a permanent organ of IT
9、U. 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 meets every four years, establishes the topics f
10、or 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-Ts purview, the necessary standards are prepared
11、 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 is voluntary. However, the Recommendation may co
12、ntain 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“ and the negative equivalents are used to express
13、 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 involve the use of a claimed Intellectual Propert
14、y 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 Recommendation, ITU had not received notice of in
15、tellectual 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 at http:/www.itu.int/ITU-T/ipr/. ITU 2009 All
16、rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.1081 (10/2008) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 4 Abbreviations and acronyms 2 5 Conventions 2 6 IPTV performance monitoring p
17、oints. 2 7 Performance monitoring point definitions 3 7.1 Monitoring point 1 PT1. 4 7.2 Monitoring point 2 PT2. 4 7.3 Monitoring point 3 PT3. 4 7.4 Monitoring Point 4 PT4. 5 7.5 Monitoring point 5 PT5. 6 8 Security considerations. 6 Rec. ITU-T G.1081 (10/2008) 1 Recommendation ITU-T G.1081 Performan
18、ce monitoring points for IPTV 1 Scope This Recommendation defines performance monitoring points which will allow the service provider/network operator to monitor the performance of the complete IPTV service delivery to the end-user. Successful deployment of IPTV services requires performance monitor
19、ing at the customer premises (e.g., set-top-box), key aggregation points (e.g., DSL access multiplexer (DSLAM) or cable modem termination system (CMTS) and at interconnect points between disparate network domains and service provider domain boundaries. Performance monitoring can help in: Finding err
20、ors in an end-to-end system (system debugging). Checking the resource utilization and the workload of system components. Comparing values (metrics) regarding performance of different system deployments. Providing a base for modelling the system. Identifying system bottlenecks. Optimizing IPTV networ
21、k deployment. Ensuring that system performance does not degrade with time. The goal of performance monitoring is to provide end-users of IPTV services with a high user experience by identifying, localizing and quantifying service and network issues. 2 References The following ITU-T Recommendations a
22、nd 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 Recommendations and other references are subject to revision; users of this Recommendation are therefore enco
23、uraged 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 regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone do
24、cument, the status of a Recommendation. ITU-T Y.1540 Recommendation ITU-T Y.1540 (2007), Internet protocol data communication service IP packet transfer and availability performance parameters. ITU-T Y.1543 Recommendation ITU-T Y.1543 (2007), Measurements in IP networks for inter-domain performance
25、assessment. ITU-T Y.1544 Recommendation ITU-T Y.1544 (2008), Multicast IP performance parameters. 3 Definitions This Recommendation defines the following term: 3.1 platform: A hardware and/or software architecture that serves as a foundation or base for realizing a certain functionality. 2 Rec. ITU-
26、T G.1081 (10/2008) 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: CMTS Cable Modem Termination System DSLAM Digital Subscriber Line Access Multiplexer EPG Electronic Programme Guide IPTV Internet Protocol Television NMS Network Management System OSS O
27、perations Support System QoE Quality of Experience QoS Quality of Service STB Set-Top Box VoD Video on Demand 5 Conventions In this document: The keywords “is recommended“ indicate a requirement which is recommended but which is not absolutely required. Thus, this requirement need not be present to
28、claim conformance. The keyword “may“ indicates a requirement which is optional. 6 IPTV performance monitoring points The entire IPTV content delivery chain can be divided into multiple domains. Operators at domain borders have the option to perform monitoring which, when taken together, forms an end
29、-to-end monitoring topology. This domain approach is independent of any specific monitoring method. Monitored performance characteristics, across a single domain or multiple domains, can be integrated with existing or new operations support systems (OSSs) and/or network management systems (NMSs). Fi
30、gure 1 IPTV domains Rec. ITU-T G.1081 (10/2008) 3 The exact topology and domains will vary from one operator to another; however, monitoring can be applied at each domain boundary. An example topology with generalized domain boundaries is shown in Figure 1. These domains are further divided into spe
31、cific monitoring domains in Figure 2. Within each domain, different aspects can be monitored at each domain boundary as outlined below. Figure 2 IPTV performance monitoring points A complete performance monitoring system is recommended to include a performance monitoring management platform to trans
32、late the measured data from the monitoring points into actionable knowledge. Functions of the management platform could include data storage, analysis, correlation, fault identification, root cause analysis, report generation and visualization. The range of the management platform(s) may cover all d
33、omains as shown in Figure 2. The interfaces between the performance monitoring management platform(s) and the monitoring points will be further defined in the future. 7 Performance monitoring point definitions This clause provides a basic description of each monitoring point shown in the previous cl
34、ause. The capabilities and parameters listed below are not an exhaustive list. Some parameters may be difficult to obtain in some scenarios. Conversely, there may be some other parameters that are essential. These are still under study. 4 Rec. ITU-T G.1081 (10/2008) 7.1 Monitoring point 1 PT1 This p
35、oint demarcates the domain border between content provision and IPTV control. PT1 is located at the domain border between content providers (content owners and aggregators) and an IPTV service provider. PT1 enables the measurement of source audiovisual quality and metadata verification, and the anal
36、ysis of information to be exchanged between the content provider and IPTV service provider. PT1 may capture the following information: coding parameters of video, audio and text content; quality parameters of video, audio and text content; acknowledgement for the report of source content transfer re
37、ceipt. PT1 may support the following capabilities: real-time request/response transactions by the protocols involved; real-time notifications of asynchronous events; reliable and secure delivery of any messages involved; clock synchronization with other monitoring points; identification of various c
38、ontent providers; report testing information for quality parameters of video, audio and text content from various content providers to the service quality monitoring platform. 7.2 Monitoring point 2 PT2 This point is located at the domain border between the service provider and network provider. It
39、should aim for original streaming quality monitoring. PT2 monitors the service provider stream quality at the head-end egress. PT2 may capture the following information: quality parameters of stream media from the core node of the service provider; performance parameters of EPG servers at the core n
40、ode of the service provider; performance parameters of VoD servers at the core node of the service provider; performance parameters of service-related servers at the core node of service provider. PT2 may support the following capabilities: real-time request/response transactions by the protocols in
41、volved; real-time notifications of asynchronous events; reliable and secure delivery of any messages involved; clock synchronization with other monitoring points; identification of various servers; report information for quality parameters of video, audio and text content and performance parameters
42、of servers to the service quality monitoring platform. 7.3 Monitoring point 3 PT3 This point is located at the boundary between the IP core and IP access networks for monitoring of IP-related performance parameters. This point can be placed on any type of interface between the IPTV core network and
43、the access network. Rec. ITU-T G.1081 (10/2008) 5 PT3 may capture the following information: Source network segment and destination network segment to be measured. IP network performance as defined in ITU-T Y.1540. Recommended methods of measurement are found in ITU-T Y.1543: Mean one-way delay. One
44、-way packet delay variation. Packet loss ratio. Packet loss profile. Path unavailability. Multicast IP network performance parameters as defined in ITU-T Y.1544: Successful join time. Successful leave time. Group mean one-way delay. Group IP service availability. Mean group loss ratio. PT3 may suppo
45、rt the following capabilities: real-time request/response transactions; real-time notifications of asynchronous events; reliable and secure delivery of any messages involved; clock synchronization with other monitoring points; submission of information for quality parameters of IP network to service
46、 quality monitoring platform; access to raw IP information (e.g., packet headers, type of codec) of the audiovisual or text stream; able to capture information on quality originating from end-user devices. 7.4 Monitoring point 4 PT4 This point is closest to the user where monitoring the quality of s
47、treaming, audiovisual quality and IPTV service attributes are important. Monitoring at this point can be implemented by introducing the performance monitoring function in home gateways and STBs, for example. PT4 may capture the following information: Source network segment and destination network se
48、gment to be measured. Access the service quality information and stream media quality information of the IPTV service platform from edge point of IPTV. Access to raw IP information (e.g., packet headers, type of codec) of the audiovisual or text stream. IP network performance parameters as defined i
49、n ITU-T Y.1540. Recommended methods of measurement are found in ITU-T Y.1543: Mean one-way delay. One-way packet delay variation. Packet loss ratio. Path unavailability. 6 Rec. ITU-T G.1081 (10/2008) Multicast IP network performance parameters as defined in ITU-T Y.1544: Successful join time. Successful leave time. Group mean one-way delay. Group IP service availability. Mean group loss ratio. PT4 may be able
