IPTV Promotes Advent of Digital Home Living

Abstract:Digital home has been attracting attention from various industries. However, its sluggish development should not be ignored. Communications and media entertainment services are major demands of the current digital home market, and digital home based on telecommunication networks can meet these demands well through IPTV audio/video and value-added application services. IPTV delivers audio/video broadcast, audio/video on demand, time-shifted services, as well as value-added services such as information service, audio/video communications, interactive games, instant communications, karaoke and distance learning. Therefore, IPTV is well suited to digital home development and makes digital home applications more applicable. Breakthroughs in ease of use and service innovation are expected to drive the digital home forward, and subscribers will be able to enjoy triple-play (data, voice and video) services due to the collaboration between different devices.

Foundation Sponsored Program: National Development and Reform Commission Hi-Tech (2005) (No. 2942)

      The concept of digital home or home network was originally proposed by consumer electronics vendors, and then followed by the concept of Information Appliances (IA) introduced in the home appliance industry. Due to the technologies and applications, these concepts have experienced sluggish growth ever since. While the IT and home appliance industries are expecting a booming digital home market, the telecom industry also puts forward the new concept of digital home or home network from its own perspective. By constructing a complete home network architecture, digital home based on the telecom network not only allows home devices to interconnect and interoperate with each other, but also enables the home network to connect to the telecom network via the home gateway, thus extending the public network functions and applications to home . With the above architecture, home network offers diversified services and provides home users with integrated voice, video, data, multimedia, control and management functions to achieve full delivery and sharing of information between internal home terminals and external public networks as well as between internal home terminals. According to the related industry investigation and analysis, communications and media entertainment services, vividly called triple-play services by the industry, are major concerns of the present digital home market. IPTV is a media entertainment service rolled out by the telecom operator over its broadband IP network. It relies on network video resources, using TV sets for display, and is expected to be a boost to the development of the digital home.

1 Digital Home and IPTV
The IPTV concept has been introduced and develops with a focus on user experience services. Using the "TV set plus set-top box" as its terminal device, the IPTV system provides broadband users with an interactive TV experience through the telecom operator磗 broadband IP network. Therefore, IPTV is actually a kind of multimedia
value-added services carried on the broadband data network. Related to home experience, IPTV is inevitably an important part of the digital home.

      Standard organizations in the telecom field have basically reached a consensus on the digital home or home network. Among them the main organizations are ITU-T, the ADSL Forum and China Communications Standards Association (CCSA)[1].

      In terms of function, the home network consists of access, core processing and control, application adaptation and application terminal logic entities, as shown in Figure 1. Separated or combined functions of the above logic entities are fulfilled by terminal products available or to be available in the home network. Physical devices of the home network are basically divided into 4 categories: the access terminal device, home gateway[2- 3], adaptation device, and user terminal device. In the home network architecture, the set-top box[4] is an adaptation device and the corresponding user terminal device is the TV set. In this sense, the "set-top box plus TV set" is the final bearer of multiple services, which are supported by the home network using the home gateway for core processing and control.

2 IPTV Applications in Digital Home
Digital home can offer 3 basic service types: home communication services, home entertainment services and home control services, while IPTV services include basic audio/video broadcast, audio/video on demand, time-shifted services, as well as value-added application services such as information service, audio/video communications, interactive games, instant communications, karaoke and distance learning.

      Obviously, IPTV is well fit for digital home development and may make digital home applications more practical. The basic application model of IPTV is shown in Figure 2.

2.1 Basic Audio/Video Services
Basic audio/video services include: broadcast service, on-demand service and time-shifted TV.

      The broadcast service can actively deliver the same audio/video streams to multiple users simultaneously. The users need to register for a certain broadcast channel before they enjoy a broadcast service. On the system side, the instant content of this broadcast channel is delivered simultaneously to all registered users of the channel. Generally, the broadcast service adopts the IP multicast technology or live-TV relay technology to transfer TV programs over the IP network, so it is required that the bearer network support IP multicast and provide an IP QoS guarantee as well as the related QoS guarantee for the internal home network when multiple application services coexist.

      The on-demand service fulfills playing a TV program as required by an individual user, with video steams delivered in the point-to-point mode. The service thoroughly changes TV viewing habits. It turns passive TV viewing into active program selection on demand. Viewers can select TV programs they like, which greatly satisfy viewers? personalized demands.

      Time-shifted TV is a new service that integrates broadcast and on-demand services. With it, viewers can pause when they are watching a program on a certain broadcast TV channel, and then resume the program where they left off. This way they avoid missing important content. They can also fast forward and rewind the program the same way as they enjoy a DVD program.

2.2 Value-added Services
Communication services in the IPTV system belong to value-added services and cover Internet phone, video communications, home mailbox and Short Message Service (SMS). As an expansion of traditional telecom voice service, this kind of service delivers point-to-point and point-to-multipoint audio/video streams, pictures and text messages between the end users (home) and the Service Providers (SP). Particularly the video communication service can change the situation that video terminals are high in price, user groups are restricted, and service expansion doesn磘 bring an increase in revenue generation.

      According to the game modes, game services can be divided into single-PC games and multiplayer network games. The single-PC game is a man/machine interactive entertainment that is less demanding on the game environment than the network game and brings fun to players without consideration of the network condition, on-line time of their game partners and other factors. The multiplayer network game is most attractive to players because it enables interaction with the game server or other players via the broadband network.

      Value-added services provided by IPTV also include information services and convenient services.

3 Technology and Service Trends of IPTV in Digital Home
Easy use of devices and service innovation will become two major concerns for the development of IPTV and the digital home.

3.1 Development Trends of IPTV Technology
The home network on which IPTV services are based should provide the following capabilities:

• SPs can use the home network to provide users with diversified services.
• The home network can provide necessary means for management, security, and QoS guarantee.
• The home network can support and be independent of various transmission technologies.
• The home network can support IP-based equipment and non-IP-based equipment.
• The home network architecture can provide flexibility and scalability for easy addition of new functional entities and deployment of new services.
  

      Most technologies used to fulfill these network capabilities have aroused concerns from both SPs and equipment vendors. However, considering users are different in age, education, occupation and personal history, IPTV services and the home network system should enable simple operation, easy use and reliable performance to meet the demands of different user groups. Now research is being conducted on device/service discovery and control in the home network, and collaborative technology between devices. The home network is a dynamic environment, the new devices should discover and collaborate with other devices. Therefore, the devices should support interoperability, automatic configuration, device discovery and service discovery, as well as being networked. So far, the widely used international standard is the Digital Living Network Alliance (DLNA) standard based on Universal Plug and Play (UPnP), and the Chinese standard is the Intelligent Grouping and Resource Sharing (IGRS). With similar operating principles, the two standards both use device and service description files to describe device features and services supported, and achieve the goal of automatic configuration of the home network, resource sharing between devices, and collaborative service between devices through a series of procedures and methods including addressing, discovery, description, control, eventing and presentation[5-7].

3.2 Development Trends of IPTV Services
In the future, the development of services will not depend on the introduction of new equipment. Instead, collaboration between devices will be the source of service innovation. Figure 3 demonstrates service applications in the triple-play mode.

      Through collaboration between devices, the home network system in Figure 3 allows users the triple-play (data, voice and video) service experience. For example, IPTV allows users to enjoy local live broadcasting, video play and other services at home. Remote monitoring can be fulfilled by home gateway and network camera, and video communications fulfilled by home gateway, cordless telephone, and the set-top box plus TV. In this way, users? existing investment can be fully protected.

4 Conclusion
Although the digital home and home network have a long way to go, the development of IPTV services is moving into top gear. As an important part of the digital home, IPTV services are collaborating with the digital home for a joint development, and speeding up the advent of the digital home era.

References
[1] ITU-T J.190 Architecture of MediaHomeNet that Supports Cable-based Services[S]. 2002.
[2] ITU-T J.191 IP Feature Package to Enhance Cable Modems[S]. 2004.
[3] ITU-T J.192 A Residential Gateway to Support the Delivery of Cable Data Services[S]. 2004.
[4] ITU-T J.193 Requirements for the Next Generation of Set-top Boxes[S]. 2004.
[5] DLNA. DLNA Home Networked Device Interoperability Guidelines v1.0[S]. 2004.
[6] SJ/T 11310?2005  ????????????, ?1??: ????[S]. 2005.
[7] SJ/T 11311?2005  ????????????, ?4??: ????????[S]. 2005.

Manuscript received: 2006-03-18

Author Introduce:

  Wang Min graduated from Beijing Institute of Technology. He works as a chief engineer of the multimedia terminal products line at the Network Division of ZTE Corporation. He has undertaken several product R&D programs concerning ATM, DSLAM and home gateway. Now he is engaged in the study of digital home, home network, IPTV and home gateway.