BROADBAND SERVICE BASED ON DSM-CC
Wang Ji · 2000
With the development of broadband network, interactive multimedia service, including video on demand, distance learning, electronic shopping and so on, is available to modern society. However, companies from different industries always developed broadband service systems vertically and orthogonally in last years, which disables interoperability between applications. Therefore, the Moving Picture Expert Group of ISO/IEC developed a series of MPEG standards, MPEG 1, MPEG 2 and MPEG 4, to achieve universal interoperability between equipment of different vendors. MPEG are more than an integrated audio visual coding standard, of which the Digital Storage Medium Command and Control (DSM CC) section provides a set of protocols for applications to access MPEG information in a variety of digital storage medium (DSM). DSM CC is independent of terminal devices and network, which makes it possible for industry to carry out broadband service widely. This paper addresses broadband service based on DSM CC as an attractive solution in the near future. Section 2 presents several models of broadband service based on DSM CC from points of physical network, logical session and communication protocol respectively. A physical model, which consists of core ATM network and Hybrid Fiber/Coaxial Cable (HFC) is proposed as the infrastructure for broadband service. This infrastructure is economical as well as flexible enough to achieve satisfying Quality of Service. Then an object oriented session model is described to abstract the interaction between client and server in broadband service. The protocol stack and characteristics of communication model are also given. Section 3 discusses the technology of using DSM CC to transfer broadband service. DSM CC provides a set of protocols, including session, client configuration, download, broadcast and so on, to settle various problems involving in transferring broadband service. Based on these protocols we can design interface for application to invoke. Section 4 discusses the technology of using DSM CC to control MPEG stream. A set of control primitives is designed and the structure to control the playback and recording of MPEG stream is expounded. Section 5 presents an application instance of News on Demand to demonstrate the process of broadband service based on DSM CC. Finally conclusions and possible directions for future work are presented.