1、 International Telecommunication Union ITU-T Y.1901TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (01/2009) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Internet protocol aspects IPTV over NGN Requirements for the support of IPTV services Recom
2、mendation ITU-T Y.1901 ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Network aspects Y.300Y.399 Interfaces and protocols Y.
3、400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600Y.699 Security Y.700Y.799 Performances Y.800Y.899 INTERNET PROTOCOL ASPECTS General Y.1000Y.1099 Services and applications Y.1100Y.1199 Architecture, access, network capabilities and resource manageme
4、nt Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network performance Y.1500Y.1599 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 IPTV over NGN Y.1900Y.1999 NEXT GENERATION NETWORKS Frameworks and functional
5、architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities and service architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Numbering, naming and addressing Y.2300Y.2399 Network management
6、 Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Future networks Y.2600Y.2699 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T Y.1901 (01/2009)
7、i Recommendation ITU-T Y.1901 Requirements for the support of IPTV services Summary Recommendation ITU-T Y.1901 specifies the high level requirements to support IPTV services. These include IPTV requirements for service offering, network aspects, QoS and QoE, service and content protection, end syst
8、em, middleware and content. Source Recommendation ITU-T Y.1901 was approved on 23 January 2009 by ITU-T Study Group 13 (2009-2012) under the WTSA Resolution 1 procedure. Keywords Accounting and charging, content, content discovery and selection, home network, IPTV, IPTV architecture, IPTV service, I
9、PTV terminal device, metadata, middleware, mobility, multicast, QoE, QoS, security, service and content protection, service discovery and selection, service navigation, traffic management. ii Rec. ITU-T Y.1901 (01/2009) FOREWORD The International Telecommunication Union (ITU) is the United Nations s
10、pecialized agency in the field of telecommunications, information and communication technologies (ICTs). 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 issuing Recommendations on th
11、em 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 these topics. The approval of ITU-
12、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 expression “Administration“ is used
13、 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 applicability) and compliance with the Re
14、commendation 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 Recommendation is required of any
15、 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 of claimed Intellectual Proper
16、ty 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 Recommendation. However, impl
17、ementers 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 rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior writt
18、en permission of ITU. Rec. ITU-T Y.1901 (01/2009) iii CONTENTS Page 1 Scope 1 1.1 Organization . 1 1.2 IPTV domains. 1 2 References. 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Recommendation. 3 4 Abbreviations and acronyms 6 5 Conventions 8 6 Requirements 8 6.1 General
19、 aspects. 8 6.2 QoS and performance aspects 13 6.3 Security aspects including service and content protection. 15 6.4 Network related aspects 20 6.5 End systems and interoperability aspects. 22 6.6 Middleware, application and content aspects. 35 6.7 Public interest . 43 Appendix I Public interest cro
20、ss-reference . 47 Bibliography. 49 Rec. ITU-T Y.1901 (01/2009) 1 Recommendation ITU-T Y.1901 Requirements for the support of IPTV services 1 Scope This Recommendation specifies the high level requirements to support IPTV services. These include IPTV requirements for service offering, network aspects
21、, QoS and QoE, service and content protection, end system, middleware and content. 1.1 Organization The taxonomy that articulates this Recommendation is therefore twofold: A functional taxonomy, which aims at reflecting the fact that IPTV services are deployed and operated according to the combined
22、activation of a set of elementary capabilities IPTV traffic forwarding and routing, IPTV quality of service and quality of experience, IPTV security, IPTV middleware, etc. Within each of the aforementioned functional areas, a further classification organizes the requirements into mandatory requireme
23、nts, recommended requirements and optional requirements. 1.2 IPTV domains Figure 1-1 shows the main domains that are involved in the provision of IPTV services ITU-T Y.1910. It is provided in this Recommendation to help the understanding of requirements which in some way relate to these domains. The
24、se domains do not define a business model. Also, one provider may play in multiple domains in the provision of an actual service. Figure 1-1 IPTV domains 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisi
25、ons 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 investigate the possibility of applying the most recent edition of the Recommendations
26、 and other references listed below. A list of the 2 Rec. ITU-T Y.1901 (01/2009) 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 Y.1541 Recommendatio
27、n ITU-T Y.1541 (2006), Network performance objectives for IP-based services. ITU-T Y.1910 Recommendation ITU-T Y.1910 (2008), IPTV functional architecture. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 aspect ratio b-ITU-T T.101: The
28、ratio of the width to the height of a rectangular area, such as the defined display area. 3.1.2 broadcast b-ITU-T M.60: One-way transmission from one point to two or more other points. 3.1.3 content provider ITU-T Y.1910: The entity that owns or is licensed to sell content or content assets. 3.1.4 e
29、lementary stream b-ITU-T H.222.0: Generic term for either the coded video, the coded audio, or other coded bit stream in the PES packet. NOTE PES stands for packetized elementary stream. 3.1.5 end-user ITU-T Y.1910: The actual user of the products or services. NOTE The end-user consumes the product
30、or service. An end-user can optionally be a subscriber. 3.1.6 home network b-ITU-T H.622: Home network is the collection of elements that process, manage, transport, and store information, thus enabling the connection and integration of multiple computing, control, monitoring, communication and ente
31、rtainment devices in the home. 3.1.7 mobility b-ITU-T Q.1706: The ability for the user or other mobile entities to communicate and access services irrespective of changes of the location or technical environment. 3.1.8 network provider ITU-T Y.1910: The organization that maintains and operates the n
32、etwork components required for IPTV functionality. NOTE 1 A network provider can optionally also act as service provider. NOTE 2 Although considered as two separate entities, the service provider and the network provider can optionally be one organizational entity. 3.1.9 service information b-ITU-T
33、J.200: Data which describes programs and services. 3.1.10 service provider b-ITU-T M.1400: A general reference to an operator that provides telecommunication services to customers and other users either on a tariff or contract basis. A service provider may or may not operate a network. A service pro
34、vider may or may not be a customer of another service provider. NOTE Typically, the service provider acquires or licenses content from content providers and packages this into a service that is consumed by the end-user. 3.1.11 subscriber b-ITU-T M.3050.1: The subscriber is responsible for concluding
35、 contracts for the services subscribed to and for paying for these services. 3.1.12 subscription b-ITU-T Q.1741.3: A subscription describes the commercial relationship between the subscriber and the service provider. Rec. ITU-T Y.1901 (01/2009) 3 3.2 Terms defined in this Recommendation This Recomme
36、ndation defines the following terms: 3.2.1 accessibility feature: An additional content component that is intended to assist people hindered in their ability to perceive an aspect of the main content. Examples: captions for the hard of hearing, subtitles in various languages, sign-language interpret
37、ation video and descriptive audio. 3.2.2 acquisition: The process of obtaining content by the end-user. NOTE For content with accessibility features, this means that the content will be available in a form that can be used by the end-user. 3.2.3 audio description: This service provides a commentary
38、describing the visual events pertinent to the content and augments the dialog in the content. NOTE Audio description is primarily intended to assist users who are unable to see the video content clearly. The narrative passages fit between the dialogue and other significant audio content so as not to
39、 interfere with it. Ideally, the user can control the volume and spatial positioning of the audio or derive it from a separate output. 3.2.4 captions: Captions provide a real-time on-screen transcript of the dialogue as well as any sound effects. NOTE This service can be provided by means of either
40、textual or graphical supplementary content. The captions and the dialogue are usually in the same language. The service is primarily to assist users having difficulty hearing the sound. Ideally, users may have some control over the position and size of the presentation. Different speakers are distin
41、guished, usually by different colours. 3.2.5 channel: Content formatted as a selectable set of data and transported as part of a data stream. 3.2.6 channel changing: The act of changing from one channel to another. 3.2.7 client personal video recorder (cPVR): Same as PVR except that the recording de
42、vice is located at the end-users premises. 3.2.8 content protection: Ensuring that an end-user can only use the content they have already acquired in accordance with the rights that they have been granted by the rights holder. 3.2.9 content segment: A continuous portion of a piece of content, for ex
43、ample, a single topic in a news programme. 3.2.10 content tracing: A process to enable the identification of the (arbitrary) origin of content, and/or the responsible party (e.g., the end-user), to facilitate subsequent investigation in the event of unauthorized content copying or distribution. NOTE
44、 Content tracing information may be attached to content either as metadata, or as a forensic watermark. 3.2.11 delivery network gateway functions (DNGF): Set of functions that mediate between the network and service provider domains and the IPTV terminal function (ITF). NOTE A device implementing th
45、e DNGF is commonly referred to as the residential gateway (RG) or delivery network gateway (DNG). 3.2.12 delivery network gateway (DNG): A device implementing the DNGF. NOTE DNG also is commonly referred to as the residential gateway (RG). 3.2.13 electronic program guide (EPG): A structured set of d
46、ata, intended to provide information on available content that may be accessed by end-users. 3.2.14 end system: A single or set of consumer devices that support IPTV services (e.g., delivery network gateway, display). 4 Rec. ITU-T Y.1901 (01/2009) 3.2.15 Internet Protocol Television (IPTV): Multimed
47、ia services such as television/video/audio/text/graphics/data delivered over IP-based networks managed to support the required level of QoS/QoE, security, interactivity and reliability. 3.2.16 IPTV terminal function (ITF): The end-user function(s) associated with a) receiving and responding to netwo
48、rk control channel messages regarding session set-up, maintenance, and tear-down, and b) receiving the content of an IP transport from the network and rendering. 3.2.17 IPTV terminal device: A terminal device which has ITF functionality, e.g., a STB. 3.2.18 linear TV: A television service in which a
49、 continuous stream flows in real time from the service provider to the terminal device and where the user cannot control the temporal order in which contents are viewed. 3.2.19 metadata: Structured, encoded data that describe characteristics of information-bearing entities to aid in the identification, discovery, assessment, and management of the described entities. NOTE EPG metadata has many applications and may vary in depth from merely identifying the content package title or information to p
