Packet video transmission over a broadband implicit token passing LAN

The authors present a quantitative approach to the design of packet video transport systems for shared-access, broadband media. The proposed methodology is illustrated by focusing on the problem of supporting a high-quality multipoint-to-multipoint compressed video service using a 200-Mb/s implicit-token-passing (ITP) fiber-optic LAN (local area network). The authors develop accurate simulation models, driven by realisitic broadcast-quality AST-DPCM (adaptive spatio-temporal differential pulse code modulation) compressed video sources, for the example ITP-LAN system. The models developed are used to determine design tradeoffs among channel throughput, video quality, and the transport-level and media-access-level protocol features and parameters implemented in the packet video network interface unit. It is shown that with appropriate transport and channel-access protocols, high efficiency of channel use can be achieved with reasonable buffering requirements, without the use of adaptive coding strategies.