1、 International Telecommunication Union ITU-T J.701TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (10/2008) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Secondary distribution of IPTV services Broadcast-centric IPTV terminal middleware Recomme
2、ndation ITU-T J.701 Rec. ITU-T J.701 (10/2008) i Recommendation ITU-T J.701 Broadcast-centric IPTV terminal middleware Summary Recommendation ITU-T J.701 defines components of a broadcast-centric IPTV terminal middleware and provides a high-level description of functionality necessary to support IPT
3、V services. These definitions and descriptions are intended to provide a migration path from existing terminal middleware for current digital broadcasting, with enhancements for IPTV support, to meet immediate market demand to deploy IPTV services. This Recommendation also describes the terminal mid
4、dleware architecture and its relationship with the service platform. Additionally, this Recommendation provides a table of application programming interface (API) classifications. Source Recommendation ITU-T J.701 was approved on 29 October 2008 by ITU-T Study Group 9 (2005-2008) under Recommendatio
5、n ITU-T A.8 procedures. ii Rec. ITU-T J.701 (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
6、 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), which meets every four years, es
7、tablishes 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 within ITU-Ts purview, the necessary
8、standards are prepared 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
9、 Recommendation may contain 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 equivale
10、nts are used to express 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 claim
11、ed Intellectual Property 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 no
12、t received notice of intellectual 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/IT
13、U-T/ipr/. ITU 2010 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T J.701 (10/2008) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this
14、Recommendation. 1 4 Abbreviations and acronyms 1 5 Broadcast-centric IPTV terminal middleware 2 6 Broadcast-centric IPTV terminal middleware architecture 3 6.1 IPTV terminal middleware components and APIs. 4 6.2 Classification of IPTV terminal middleware components APIs 9 Bibliography. 10 Rec. ITU-T
15、 J.701 (10/2008) 1 Recommendation ITU-T J.701 Broadcast-centric IPTV terminal middleware 1 Scope This Recommendation defines components of a broadcast-centric IPTV terminal middleware and provides a high-level description of functionality necessary to support IPTV services. These definitions and des
16、criptions are intended to assist in the establishment of a migration path from existing terminal middleware for current digital broadcasting, with enhancements for IPTV support, to meet immediate market demand to deploy IPTV services. 2 References The following ITU-T Recommendations and other refere
17、nces 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 encouraged to inves
18、tigate 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 document, the sta
19、tus of a Recommendation. ITU-T J.200 Recommendation ITU-T J.200 (2001), Worldwide common core Application environment for digital interactive television services. ITU-T Y.1910 Recommendation ITU-T Y.1910 (2008), IPTV functional architecture. 3 Definitions 3.1 Terms defined elsewhere This Recommendat
20、ion does not use any terms the following terms defined elsewhere. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 resource abstraction/middleware interface: An interface between the resource abstraction layer and the middleware service that encapsulate
21、s OS operations and the resources layer, and provides an abstract view of the resource layer. 3.2.2 resources: The native hardware and software entities that provide certain functionality to the middleware services component through the resource abstraction layer. The middleware service functions ar
22、e provided to the application layer through the API of the middleware services. 3.2.3 service components: The components that offer functionalities to any upper layers, regardless of the type of software and hardware in the resource layer. 4 Abbreviations and acronyms This Recommendation uses the fo
23、llowing abbreviations and acronyms: API Application Programming Interface EPG Electronic Programme Guide GUI Graphical User Interface HTML Hypertext Markup Language 2 Rec. ITU-T J.701 (10/2008) HTTP Hypertext Transfer Protocol HW Hardware OS Operating System PVR Personal Video Recorder RAL Resource
24、Abstraction Layer RAM Random Access Memory RTSP Real Time Streaming Protocol SCP Service and Content Protection SIP Session Initiation Protocol SW Software VOD Video on Demand 5 Broadcast-centric IPTV terminal middleware The IPTV middleware supports the variety of functionalities (e.g., EPG, PVR, ga
25、ming, etc.) provided by the IPTV architecture to the IPTV terminal devices. Two types of middleware configuration can be considered: terminal middleware and distributed service enabler. This Recommendation focuses on the terminal middleware, whereas the definition of the distributed service enabler
26、and its technical details are under study and may be the subject of a future ITU-T Recommendation. Figure 5-1 provides an overview of the IPTV middleware architecture, where the terminal middleware is illustrated on the left side. Figure 5-1 IPTV middleware architecture The following description of
27、IPTV middleware architecture components includes more issues than those addressed within the scope of this Recommendation. IPTV application layer The application layer is the layer where operators and third parties provide services and applications. These services and applications include EPG applic
28、ations, VOD, linear TV streams, PVR, games, Internet applications as well as other value-added services. Rec. ITU-T J.701 (10/2008) 3 API An API is essentially a set of operations (or methods) that can be invoked on a component, each of which causes the component to exhibit behavioural functionality
29、. IPTV middleware The IPTV middleware is divided into a service platform middleware and a terminal middleware linked through a bridge. The IPTV middleware invokes the lower layer resources (e.g., network interfaces) to control them, and provides APIs for upper layers. It is recommended that the IPTV
30、 middleware implement the relevant functional modules and end-user functions described in ITU-T Y.1910. The IPTV middleware also provides some specific functions: resource management function, a functional module to manage system resources in IPTV terminal devices; application management function, a
31、 functional module to manage the life cycle of the applications and interaction operations between them. Resource abstraction layers The resource abstraction layer (RAL) makes the middleware independent of lower software and hardware layers. The resources abstracted in the RAL include: software reso
32、urces, such as drivers and OS; hardware resources, such as computing devices, CPU, storage devices, codec, rendering devices (e.g., display, speaker), IO devices. 6 Broadcast-centric IPTV terminal middleware architecture Figure 6-1 shows the IPTV terminal middleware architecture (note that this arch
33、itecture is compatible with the architecture shown in Figure 1 of ITU-T J.200). Figure 6-1 IPTV terminal middleware architecture Overview Resource abstraction layer (RAL) The IPTV terminal middleware is hardware-agnostic. A specific resource abstraction layer (RAL) exists for each specific hardware
34、and operating system. This provides the necessary interface to the 4 Rec. ITU-T J.701 (10/2008) lower layers (e.g., RAM, network access, hard drive, USB port, etc.). The RAL interface is designed so that device drivers can be written irrespective of the service logic adaptation layer. Service logic
35、adaptation layer The service logic adaptation layer is made of service components. The service components are components that offer functionalities common to all middleware implementations (e.g., service selection and presentation, service information management, PVR, security systems). They are use
36、d and enriched by the application services in order to simplify the development of service components and applications above it. The definition and the scope of services depend on the concrete functionalities deployed in the IPTV system. Nevertheless, some service components can be defined that are
37、generic in nature: system and resource management component; media management component; communication component; security component; metadata access component; user interaction component; audience measurement component. All these components can optionally use the functions available on the network.
38、 Presentation engine layer The presentation engine layer may include various engines along with a set of high-level services. This layer is built on top of the service logic adaptation layer. For procedural applications, the IPTV terminal middleware is recommended to be equipped with elements define
39、d in Figure 2 of ITU-T J.200, in the service logic adaptation layer and the presentation engine layer. For declarative applications, the IPTV terminal middleware is recommended to be equipped with elements defined in Figure 3 of ITU-T J.200, in the service logic adaptation layer and the presentation
40、 engine layer. The definitions of “procedural application“ and “declarative application“ can also be found in ITU-T J.200. User experience and application layer The applications are either downloaded or resident. In particular, an application is powered by a presentation engine (e.g., HTML browser).
41、 An application can either have full or restricted access to the presentation engine layer features. Moreover, some applications may directly access the service logic adaptation layer without using a presentation engine or may also directly access the resource abstraction layer. 6.1 IPTV terminal mi
42、ddleware components and APIs This clause describes the functionalities of the IPTV terminal middleware components and identifies their APIs. 6.1.1 System and resource management component The system and resource management component is used to manage IPTV terminal device resources, and provide the s
43、oftware initialization API, the upgrade and download API, the system resources management API, and the terminal management API to the upper application layer. Rec. ITU-T J.701 (10/2008) 5 Software initialization and diagnosis API: An IPTV terminal middleware API that is responsible for initializing
44、the IPTV terminal device, preparing the running environment and providing diagnostic capabilities to the IPTV terminal device. This API is used to execute the following functions: configuration of the IPTV terminal device; initialization of tasks, such as application management, service and content
45、protection (SCP) task, subscriber authentication process, etc.; network connection initialization, such as to get network parameter, configure access mode, etc.; initialization of resources, such as memory, timer, I/O equipment, A/V decoder and other system resources; coordination with other IPTV te
46、rminal device APIs, such as to work with the security and authentication API (see clause 6.1.4) to start the user authentication procedure, to work together with the upgrade and download API to check software version and perform the software upgrade procedure; diagnosis of the IPTV terminal device.
47、Device software upgrade API: An IPTV terminal middleware API that is responsible for the dynamic downloading and upgrading of the IPTV terminal device. This API covers terminal middleware and lower layer. This API is used to execute the following functions: device software download and upgrade for m
48、iddleware layer; device software download and upgrade for resource abstraction layer; validity check of device software and data. Terminal management API: An IPTV terminal middleware API that is responsible for the IPTV terminal management and configuration function. This API is used to execute the
49、following functions: remote management; log management; software version management; server parameter configuration, such as server address configuration; access mode and parameter configuration; media device parameter configuration, such as the decoder; subscriber configuration, such as access account and service account. System resource management API: An IPTV terminal middleware API that is responsible for scheduling resources used by applications and managing their status. This API is used to execute the follow
