Network Protocols For Interactive TV Settop Box In An ATM-based Residential Networks

Abstract

This paper presents the design and implementation of the network protocols for a digital settop box used in an ITV system. For a full-service network, heterogeneous traffic including real-time MPEG video and non-real-time user data must be sent through the same network and then handled by the settop box. To maintain the service quality while keeping the overall hardware cost down is a very challenging task. This paper first presents the software architecture of the OS-9DAVID based settop box with emphasis on the network layers. Based on a trial system in Taiwan, testing of the system performance is conducted to further improve the settop box design. This paper presents the design of network protocols for an interactive TV settop box that has been used in the the video Information Infrastructure Testbed (WIT) in Taiwan. The trial site is located in the Hsin-Chu Scientijc Park with an initial service size of 200 families. The system is now in the final stage of system test and the service is expected to turn on by end of April 1997. The settop box developed for the trial uses 32-bit RISC processor running a real-time operating system. A network interface module is developed for adaptation to an ATM-based Fiber-to-the-Curb (FTTC) network environment. The technologies used in building the trial system conform to the DAVIC 1.1 specification, and thus the evaluation of the system becomes an interesting topic. The remaining part of this paper will discuss the operational environment of the trial system, the settop box networking capability and the video and application download performance issues.