1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T J.193TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (06/2004) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Cable modems Requirements for the next generation of set-top-boxes ITU-T Recommendation J.
2、193 ITU-T Rec. J.193 (06/2004) i ITU-T Recommendation J.193 Requirements for the next generation of set-top-boxes Summary This Recommendation defines the requirements of a Next Generation Set-Top-Box (NG-STB) that is attached to a CATV. An NG-STB receives broadcast cable services and provides a 2-wa
3、y communication channel with the cable network for service management. Source ITU-T Recommendation J.193 was approved on 29 June 2004 by ITU-T Study Group 9 (2001-2004) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. J.193 (06/2004) FOREWORD The International Telecommunication Union (ITU
4、) is the United Nations specialized agency in the field of telecommunications. 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 them with a view to standard
5、izing 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-T Recommendations is cover
6、ed 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 for conciseness to indica
7、te 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 Recommendation is achieved w
8、hen 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 party. INTELLECTUAL PROPE
9、RTY 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 Property Rights, whether asserte
10、d 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, implementors are cautioned tha
11、t this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2004 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. J.193 (06/2004) iii CONTE
12、NTS Page 1 Scope 1 2 References. 1 2.1 Normative. 1 2.2 Informative . 1 3 Terms and Definitions 2 4 Abbreviations, acronyms and conventions. 3 4.1 Abbreviations and acronyms 3 4.2 Conventions 3 5 Introduction 4 5.1 General . 4 5.2 Design Objectives. 5 5.3 Services. 6 5.4 Key features 7 5.5 Localizat
13、ion 8 6 Functional requirements . 9 6.1 General requirements 9 6.2 Security requirements. 9 6.3 Video requirements 10 6.4 Audio requirements 11 6.5 Input interface requirements. 11 6.6 Output interface requirements 11 6.7 Requirements for other Interfaces 11 6.8 Provisioning requirements 11 6.9 Mana
14、gement requirements . 12 6.10 Content management requirements 12 6.11 QoS requirements . 12 6.12 PVR requirements 13 7 Requirements for optional standardized features . 13 7.1 Requirements to incorporate a full DOCSIS cable modem into the STB 13 7.2 Requirements to incorporate a residential gateway
15、into the STB 13 8 Example architectures. 13 8.1 NG-STB supporting broadcast video and a 2-way communication channel 14 8.2 NG-STB incorporating a broadband cable modem 15 8.3 NG-STB incorporating a residential gateway 16 ITU-T Rec. J.193 (06/2004) 1 ITU-T Recommendation J.193 Requirements for the ne
16、xt generation of set-top-boxes 1 Scope This is an objectives, requirements and functional architecture Recommendation for next generation set top boxes, supporting a core digital video application suite (i.e., broadcast video), and allowing for a large variety of additional services, such as VoD, Vo
17、IP, data services, etc. This Recommendation is designed to be used for cable television networks, but the architecture does not necessarily exclude other access network interfaces. 2 References 2.1 Normative The following ITU-T Recommendations and other references contain provisions which, through r
18、eference 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 revisions; users of this Recommendation are therefore encouraged to investigate the possibility of applying the
19、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 document, the status of a Recommendation. ITU-T Recommen
20、dation J.112 (1998), Transmission systems for interactive cable television services. ITU-T Recommendation J.122 (2002), Second-generation transmission systems for interactive cable television services IP cable modems. ITU-T Recommendation J.200 (2001), Worldwide common core Application environment f
21、or digital interactive television services. 2.2 Informative ITU-T Recommendation J.83 (1997), Digital multi-programme systems for television, sound and data services for cable distribution. ITU-T Recommendation J.125 (2004), Link privacy for cable modem implementations. ITU-T Recommendation J.126 (2
22、004), Embedded Cable Modem device specification. ITU-T Recommendation J.181 (2004), Digital program insertion cueing message for cable television systems. ITU-T Recommendation J.190 (2002), Architecture of MediaHomeNet that supports cable-based services. ITU-T Recommendation J.191 (2004), IP feature
23、 package to enhance cable modems. ITU-T Recommendation J.192 (2004), A residential gateway to support the delivery of cable data services. 2 ITU-T Rec. J.193 (06/2004) 3 Terms and Definitions This Recommendation defines the following terms: 3.1 Next Generation Set-Top-Box (NG-STB): A compilation of
24、hardware and software functional entities contained within one or more physical devices, that at a baseline level provides the receiving functions for cable Broadcast services. In addition, the NG-STB MAY support the interactive functions of IP-based services, additional time-critical services betwe
25、en the HFC and the Home Network as well as extension and supplemental services. 3.2 embedded STB: A Set-Top-Box that does not use a stand-alone interface to connect to a RG. 3.3 LAN IP device: A LAN IP device is representative of a typical IP device expected to reside on Home Networks, and is assume
26、d to contain a TCP/IP stack as well as a DHCP client. 3.4 Portal Services (PS): A functional element that provides management and translation functions between the HFC and Home Network. 3.5 Residential Gateway (RG): A grouping of logical elements used to achieve HFC access for Home Network(s). 3.6 s
27、tandalone RG: A RG Services element that connects to the CM using only a standalone interface. 3.7 IP-based services: A generic term that includes QoS-controllable both-way and one-way IP-type services rendered over a CATV network on which a high-speed packet-based IP communication system is availab
28、le. Examples include IP telephony or VoIP, videoconferencing, streaming video feeds, competitive games, and other similar services. 3.8 closed captioning: Text scrolling on a television display that represents the audio portion of the program, typically provided for the hearing impaired. 3.9 home te
29、rminal: The device attached to the cable network that receives and renders services for the customer. Also known as a set top box. 3.10 conditional access: The conditional granting of access to cable services and content based upon what service suite has been purchased by the customer. 3.11 portal f
30、unctions: Functionality that resides within a Residential Gateway that provides connectivity between the cable IP network, and the home network. See ITU-T Recs J.190, J.191 and J.192 for more details. 3.12 2-way communication channel: An IP-based communications link between a NG-STB and the cable ne
31、twork service management system, for the purpose of service management communications. 3.13 core services: The set of services that MUST, at a minimum, be supported by the NG-STB. 3.14 optional services: Services, in addition to the Core Services, that can be supported by the NG-STB. 3.15 key featur
32、es: Features that MUST be included in the NG-STB in order to support the Core Services identified in this Recommendation. 3.16 optional features: Features that can be added to the NG-STB in order to support the Optional Services identified in this Recommendation. 3.17 middleware: Software within the
33、 NG-STB which provides a set of APIs that against which applications can be developed, and that provide access to the resources and services of the NG-STB. ITU-T Rec. J.193 (06/2004) 3 3.18 command and control messaging: Messaging between devices which request particular actions associated with vide
34、o service such as Play, Rewind, and Pause. 3.19 broadband cable modem: A cable modem built into the STB, which provides full Broadband access to the Internet, and is intended for customer use. In addition, cable services can be delivered via this broadband IP connection. 3.20 emergency alert system:
35、 A system, within which the NG-STB participates, that allows a service provider to distribute public emergency alarms and information about the public emergency to all of the customers attached to the cable network. 3.21 system and service information: Information about the video service, for exampl
36、e channel maps that map the programs within an MPEG transport stream, electronic programming guide data, and conditional access information. 4 Abbreviations, acronyms and conventions 4.1 Abbreviations and acronyms This Recommendation uses the following abbreviations: HFC Hybrid-Fibre/Coax HN Home Ne
37、twork HT Home Terminal IEEE Institute of Electrical and Electronics Engineers IETF Internet Engineering Task Force IP Internet Protocol MPEG Moving Picture Experts Group OSS Operations Support System PVR Personal Video Recording QoS Quality of Service RFC Request For Comments RG Residential Gateway
38、RTP Real-time Transport Protocol STB Set-Top-Box TS Transport Stream VoD Video-on-Demand VoIP Voice over IP 4.2 Conventions If this Recommendation is implemented, the key words “MUST“ and “SHOULD“ as well as “REQUIRED“ are to be interpreted as indicating a mandatory aspect of this Recommendation. Th
39、e key words indicating a certain level of significance of particular requirements that are used throughout this Recommendation are summarized below. MUST: This word or the adjective “REQUIRED“ means that the item is an absolute requirement of this Recommendation. 4 ITU-T Rec. J.193 (06/2004) MUST NO
40、T: This phrase means that the item is an absolute prohibition of this Recommendation. SHOULD: This word or the adjective “RECOMMENDED“ means that there MAY exist valid reasons in particular circumstances to ignore this item, but the full implications should be understood and the case carefully weigh
41、ed before choosing a different course. SHOULD NOT: This phrase means that there MAY exist valid reasons in particular circumstances when the listed behaviour is acceptable or even useful, but the full implications should be understood and the case carefully weighed before implementing any behaviour
42、described with this label. MAY: This word or the adjective “OPTIONAL“ means that this item is truly optional. One vendor MAY choose to include the item because a particular marketplace requires it or because it enhances the product, for example, another vendor MAY omit the same item. 5 Introduction
43、5.1 General Formerly the conventional Home Terminal (HT) was dedicated primarily to the reception of analog broadcasting services on the CATV network. This HT has evolved into a digital-type STB that handles the present MPEG-2 video and audio. This STB is a terminal unit including a tuner, demodulat
44、or, video decoding function, and conditional-access function, and is a quality-assurance-type STB. The market has also seen the emergence of a both-way-type STB with an upstream channel to transmit demand information and interactive signals. On the other hand, the rapid development of IP technologie
45、s enables the STB, with an integrated DOCSIS cable modem, to provide functions for IP-based services, provide connectivity with the Internet, diverse VoIP, real-time services for competitive games, and the like. ITU-T Rec. J.191 specifies the management of portal function, address portal function, a
46、nd DHCP portal function, among others. When these portal functions are incorporated into the upper layer of the cable modem, the cable modem will be able to be connected to or integrated into the next-generation STB as a Gateway. In addition, it will be possible to connect, through said portal funct
47、ions, the STB to the Home Network (referred to as “MediaHomeNet“ in ITU-T Rec. J.190), which is specified in ITU-T Rec. J.190. With regard to the transportation of TS over IP Networks as a kind of IP-based services, RFC 2250 describes IP encapsulation of MPEG Transport Streams for transport of video
48、 and audio streams using the Real-time Transport Protocol (RTP). The Specification recommends that consideration be given for encapsulations of the MPEG TS and Programme Stream (PS) with RTP supporting full semantics of an MPEG system. Furthermore, the next-generation STB needs to provide the functi
49、on of transferring/processing or modification of content through the use of APIs. ITU-T Rec. J.200 is available as a baseline API document for the next-generation STB. The focus of this Recommendation is a NG-STB that is attached to a CATV network. The cable access network is expected to deliver broadcasting services and IP-based services with appropriate quality and permissible latency. The NG-STB MAY also be connected with the access network via the RG, as well as to the HN which is an internal network for the home. Moreover, the NG-STB MUST provide access con
