1、 ATIS-0800008.v002 QOS METRICS FOR LINEAR BROADCAST IPTV ATIS is the leading technical planning and standards development organization committed to the rapid development of global, market-driven standards for the information, entertainment and communications industry. More than 200 companies activel
2、y formulate standards in ATIS 17 Committees, covering issues including: IPTV, Cloud Services, Energy Efficiency, IP-Based and Wireless Technologies, Quality of Service, Billing and Operational Support, Emergency Services, Architectural Platforms and Emerging Networks. In addition, numerous Incubator
3、s, Focus and Exploratory Groups address evolving industry priorities including Smart Grid, Machine-to-Machine, Networked Car, IP Downloadable Security, Policy Management and Network Optimization. ATIS is the North American Organizational Partner for the 3rd Generation Partnership Project (3GPP), a m
4、ember and major U.S. contributor to the International Telecommunication Union (ITU) Radio and Telecommunications Sectors, and a member of the Inter-American Telecommunication Commission (CITEL). ATIS is accredited by the American National Standards Institute (ANSI). For more information, please visi
5、t . Notice of Disclaimer exchanging non-proprietary information to promote the development of video networking technology and foster resolution of issues common to the video services industry; promoting interoperability by contributing to and supporting development of standards by national and inter
6、national standards bodies. ATIS-0800008.v002 iii TABLE OF CONTENTS 1 INTRODUCTION . 1 1.1 OVERVIEW/BACKGROUND 1 1.2 DOCUMENT REVISION SUMMARY . 1 1.3 GOAL. 1 1.4 PURPOSE 1 1.5 SCOPE AND ASSUMPTIONS 1 2 TERMINOLOGY 3 2.1 GLOSSARY . 3 2.1.1 Linear IPTV Service: Traditional Linear Broadcast Service. .
7、3 2.2 ACRONYMS 3 3 REFERENCES 5 3.1 NORMATIVE REFERENCES 5 ATIS 5 ATSC . 5 ITU 5 ETSI 6 Broadband Forum. 6 IETF 6 ISO/IEC. 7 SCTE . 7 Video Services Forum (VSF). 7 Other . 7 3.2 INFORMATIVE REFERENCES 7 IETF 8 4 LINEAR IPTV . 8 4.1 SERVICE DESCRIPTION . 8 4.2 LINEAR IPTV SERVICE DEPLOYMENTS. 8 4.2.1
8、 Protocol Stacks. 8 4.2.2 Encryption 9 4.2.3 Error Correction Mechanisms . 9 4.3 LINEAR IPTV MEASUREMENT POINTS 10 5 USE CASES 12 5.1 A CONSUMER TURNS ON THE ITF. 12 5.2 A CONSUMER USES THE EPG AND SELECTS AN IPTV PROGRAM/CHANNEL 12 5.3 A CONSUMER WATCHES AN IPTV PROGRAM/CHANNEL. 13 5.4 A CONSUMER C
9、HOOSES A DIFFERENT CHANNEL (CHANNEL CHANGE) 13 5.5 A CONSUMER TURNS OFF THE ITF OR SWITCHES TO COD . 14 6 LINEAR IPTV METRICS AND MEASUREMENTS 14 6.1 DEFINING ANCILLARY INFORMATION . 14 6.2 DEFINITION OF METRIC BEHAVIOR. 15 6.3 DEFINITION OF METRIC ACCURACY 15 6.4 METRICS AVAILABILITY AND RELIABILIT
10、Y. 16 6.4.1 Impacts of Encapsulation on Metrics Availability and Reliability . 17 6.4.2 Impacts of Encryption on Metrics Availability and Reliability. 18 6.4.3 Intra-period Pattern . 18 6.5 PRIMARY METRICS. 18 6.6 RECOMMENDED IPTV METRICS. 21 APPENDIX A: COMPARISON OF ATIS TEST REFERENCE POINTS AND
11、THOSE DEFINED BY THE VIDEO SERVICES FORUM (VSF) . 40 ATIS-0800008.v002 iv APPENDIX B: CONSIDERATIONS REGARDING THE SPECIFICATION OF MEAN OPINION SCORES (MOS) (INFORMATIVE) 42 B.1 INTRODUCTION . 42 B.2 MOS SPECIFICATION. 43 B.3 EXAMPLES SCALES 44 TABLE OF FIGURES FIGURE 1: IPTV LOGICAL DOMAINS AND IN
12、TERFACES . 2 FIGURE 2: ATIS IIF-DEFINED PROTOCOL STACK . 9 FIGURE 3: LINEAR IPTV MEASUREMENT MODEL . 11 FIGURE 4: CLASSIFYING QUALITY LAYERS, QOS PARAMETERS, AND QOE INDICATORS . 22 FIGURE A.1: VSF TEST POINT DIAGRAM 40 TABLE OF TABLES TABLE 1: METRICS AVAILABILITY AND RELIABILITY FOR DIFFERENT PROT
13、OCOL STACKS AND ENCRYPTION LEVELS 16 TABLE 2: PRIMARY METRICS 19 TABLE 3: SUPPLEMENTARY METRICS . 20 TABLE 4: TABLE 5 OUTLINE . 22 TABLE 5: RECOMMENDED IPTV METRICS 23 TABLE A.1 : REFERENCE POINT COMPARISON TABLE, LINEAR (BROADCAST) VIDEO 41 ATIS STANDARD ATIS-0800008.v002 ATIS Standard on QoS Metri
14、cs for Linear Broadcast IPTV 1 1 INTRODUCTION 1.1 Overview/Background This document defines an Alliance for Telecommunications Industry Solutions (ATIS) IPTV Interoperability Forum (IIF) consensus view of Quality of Service (QoS) metrics for Linear (Broadcast) Internet Protocol TV (IPTV) service. Us
15、e cases, primary metrics, IPTV metrics, definitions, measurement points, and metric applications are identified. 1.2 Document Revision Summary This is the second revision of this document. The original version was published in August 2007. Among refinements to the previous version, this version inco
16、rporates input from a joint collaboration between ATIS and the Video Services Forum (VSF) 43. The ATIS IIF and VSF worked together to define an initial set of IPTV-related content quality metrics for both video and audio in order to address the increasing requirements for measurements related to Qua
17、lity of Experience (QoE). Other noteworthy additions include defining metrics availability and reliability for different protocol stacks and encryption levels, adding metrics for Multicast Listener Discover (MLD) Join Latency and MLD Leave Latency to accommodate IPv6, and improving the definitions o
18、f previously-established metrics. 1.3 Goal The goal of this document is to define a base set of QoS metrics for Linear (Broadcast) IPTV service (as defined per ATIS-0800002 1) as completely as possible while avoiding duplication. The ATIS IIF recognizes that as the IPTV architecture is currently a w
19、ork in progress, not all QoS metrics applicable for the Linear (Broadcast) IPTV service can be envisioned at this time. 1.4 Purpose The purpose of this document is to provide the industry with a set of well-defined QoS metrics for Linear (Broadcast) IPTV service. 1.5 Scope and Assumptions This docum
20、ent provides metrics for linear television services as defined in ATIS-0800018, IPTV Linear TV Service. These metrics generally facilitate performance measurement or monitoring, unlike the fault codes in ATIS-0800028, Fault Codes for IPTV, which generally indicate hard faults. QoS metrics for public
21、 services are defined in ATIS-0800011 11. MPEG stream-layer QoS metrics are defined in ATIS-0800040 9. This standard provides some guidance for metric application, with more details provided in ATIS-0800041, Implementers Guide to QoS Metrics. Metrics for IPTV MPEG Transport Stream ATIS-0800008.v002
22、2 Monitoring are defined in ATIS-0800040 9. Multi-Program Transport Streams (MPTS) are not considered in this document. Figure 1: IPTV Logical Domains and Interfaces (Source: ATIS-0800007, Figure 1 10) Referring to Figure 1, the metrics defined in this document are focused toward the interface betwe
23、en the Network Provider and the Consumer; however they also apply to the interface between the Service Provider and Network Provider, and the interface between the Content Provider and Service Provider. It is assumed that the ITF at startup before the service is available will be involved in a varie
24、ty of setup/control communications with any IPTV oriented network/service attachment functions in the Service Provider (SP)/Network Provider (NP) networks. At this time, the ATIS IIF does not analyze the traffic in the control plane associated with this action to determine the need for QoS metrics;
25、this is for further study. This document generally assumes that MPEG Transport Stream (MPEG2-TS) on Real Time Protocol (RTP) encapsulation is used. The ATIS IIF does not assume that only RTP is used, and allows MPEG2-TS directly over User Datagram Protocol (UDP) configurations 7. It is understood th
26、at when RTP is not used, this complicates accurate calculation of several metrics including dropped packets. Additional information/alternatives to calculate such metrics without RTP is for further study. This document also does not directly address the network architecture that maps video content d
27、irectly to RTP packets not utilizing MPEG2-TS packets. This work is for further study. This standard defines an initial set of IPTV related audio metrics. Additional metrics may be of interest in the future, such as Loudness Variation, Overs/Unders, Clipping, etc., and these are for further study. A
28、TIS-0800008.v002 3 2 TERMINOLOGY 2.1 Glossary 2.1.1 Linear IPTV Service: Traditional Linear Broadcast Service. 2.1.2 Measurement Instrumentation: Measurement instrumentation refers to the ability of a device to support appropriate measurements. This device or equipment may be a dedicated measurement
29、 system or a device or equipment that is involved in the end-to-end IPTV service delivery, such as an ITF. 2.1.3 Quality of Experience (QoE): Describes the users experience. QoE can be affected by the network infrastructure, in which case we broadly group picture QoE, transaction QoE, audio QoE, and
30、 multimedia QoE. QoE may be calculated or estimated numerically using sets of QoE indicators and/or QoS metrics. 2.1.4 QoE Indicators: Individual performance indicators that can be experienced by a user. Include video indicators such as picture error blocks, transaction indicators such as channel ch
31、ange delay, audio indicators, and multimedia indicators. 2.1.5 Quality of Service Metrics: Measures of technical performance. Includes network QoS metrics such as IP packet loss as well as higher-layer metrics. 2.1.6 Use Case: A use case is an external view of a system that represents an action or s
32、equence of actions the user might perform in order to complete a task. 2.2 Acronyms AAC Advanced Audio Coding AC-3 Audio Codec 3 AL-FEC Application Layer Forward Error Correction ARQ Automatic Repeat reQuest ATIS Alliance for Telecommunications Industry Solutions AV Audio Visual AVC Advanced Visual
33、Coding BSS Business Support System CBR Constant Bit Rate COD Content on Demand DialNorm Dialogue Normalization DRM Digital Rights Management DSL Digital Subscriber Line DVB Digital Video Broadcasting (project) E-AC-3 Enhanced Audio Codec 3 EC Error Correction (FEC or retransmission) EPG Electronic P
34、rogram Guide ES Elementary Stream (MPEG) ETSI European Telecommunications Standards Institute FEC Forward Error Correction ATIS-0800008.v002 4 HE-AAC High Efficiency Advanced Audio Coding HTTP Hyper-Text Transfer Protocol IETF Internet Engineering Task Force IGMP Internet Group Management Protocol I
35、IF IPTV Interoperability Forum IP Internet Protocol IPPM-WG IETF IP Performance Metrics Working Group IPTV Internet Protocol TeleVision ITF IPTV Terminal Function ITU-T International Telecommunication Union Telecommunication Standardization Sector LKFS Loudness, K-weighted, relative to Full Scale ML
36、D Multicast Listener Discovery MOS Mean Opinion Score MP Measurement Point MPEG Motion Picture Experts Group MPTS Multi-Program Transport Streams NP Network Provider OS Operating System OSS Operations Support System PAT Program Association Table PCR Program Clock Rate (MPEG TS) PDV Packet to Packet
37、Delay Variation PES Packetized Elementary Stream PID Packet Identifier (MPEG TS) PMT Program Mapping Table PPDV Peak Packet to Packet Delay Variation PSI Program Specific Information (MPEG TS) PTS Presentation Time Stamp (MPEG TS) QoE Quality of Experience QoS Quality of Service QoSM Quality of Serv
38、ice Metrics RFC Request For Comments (IETF documents) RTP Real-Time Protocol RTSP Real-Time Streaming Protocol SCTE Society of Cable Telecommunications Engineers SP Service Provider STB Set Top Box Sync Synchronization TS Transport Stream UDP User Datagram Protocol VHE Video Head End ATIS-0800008.v0
39、02 5 VHO Video Hub Office VSF Video Services Forum VSO Video Serving Office WLAN Wireless Local Area Network 3 REFERENCES 3.1 Normative References The following standards contain provisions that, through reference in this text, constitute provisions of this report. At the time of publication, the ed
40、itions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. ATIS11 ATIS-0800002, IPTV Architecture Requirements, ATIS IIF, May
41、 16, 2006. 2 ATIS-0800004, A Framework for QoS Metrics and Measurements supporting IPTV Services, ATIS IIF, October, 2006. 3 ATIS-0800005, IPTV Packet Loss Issue, January 2007. 4 ATIS-0800006.v002, IIF Default Scrambling Algorithm (IDSA), November 2010. 5 ATIS-0800013, Media Formats and Protocols fo
42、r IPTV Services, January 2009. 6 ATIS-0800028, Fault Codes for IPTV, February 2009. 7 ATIS-0800018, IPTV Linear Service, January 2009. 8 ATIS-0800041, Implementers Guide to QoS Metrics, August 2010. 9 ATIS-0800040, IPTV MPEG Transport Stream Monitoring, June 2010. 10 ATIS-0800007, IPTV High Level Ar
43、chitecture, April 2007. 11 ATIS-0800011, QoS Metrics for Public Services, January 2008. ATSC212 ATSC A/85:2009, ATSC Recommended Practice: Techniques for Establishing and Maintaining Audio Loudness for Digital Television, 2009. 13 ATSC A/52, Digital Audio Compression Standard (AC-3, E-AC-3), Revisio
44、n B, 2005. ITU314 ITU-R BT.1359-1, Relative timing of sound and vision for broadcasting, November 1998. 1These documents are available from the Alliance for Telecommunications Industry Solutions (ATIS), 1200 G Street N.W., Suite 500, Washington, DC 20005. 2These documents are available from the Adva
45、nced Television Systems Committee (ATSC). . 3These documents are available from the International Telecommunications Union. ATIS-0800008.v002 6 15 ITU-T G.1020, SERIES G: Transmission systems and media, digital systems and networks: Performance parameter definitions for the quality of speech and oth
46、er voice band applications utilizing IP networks. 16 ITU-T Recommendation I.350, SERIES I: Integrated Services Digital Network: General aspects of quality of service and network performance in digital networks, including ISDNs, March 1993. 17 ITU-T Recommendation Y.1540, SERIES Y: Global information
47、 infrastructure and Internet protocol aspects: Internet protocol data communication service, IP packet transfer and availability performance parameters, December 2002. 18 ITU-T Recommendation Y.1541, SERIES Y: Global information infrastructure and Internet protocol aspects: Internet protocol data co
48、mmunication service, Network performance objectives for IP-based services, February 2006. 19 ITU-R BS.1770-1, Algorithms to measure audio programme loudness and true-peak audio level, 2006-2007. 20 ITU-R Recommendation BT.500, Methodology for the subjective assessment of the quality of television pi
49、ctures, 2002. 21 ITU-T Recommendation P.910, Subjective video quality assessment methods for multimedia applications, April 2008. 22 ITU-T Recommendation G.107, The E-model: a computational model for use in transmission planning, April 2009. 23 ITU-T Recommendation G.113, Transmission impairments due to speech processing, November 2007. ETSI424 ETSI TR 101 290 v1.2.1, Digital Video Broadcast (DVB); Measurement Guidelines for DVB Systems. 25 ETSI TS 102 034
