A LOCAL AREA COMMUNICATION NETWORK

摘要

A local area communication network based upon a broadcast communication system comprising an inbound channel (20) and an outbound channel (21), a plurality of stations (S1-SN) connected to both the inbound and the outbound channels, transmitting on the outbound channel (21) which utilizes an access protocol where the access protocol used by the stations (S1-SN) connected to the bus is a distributed algorithm and is based upon a conflict-free round robin (RR) access scheme. The time required to switch from one active user to the next in a round is minimized (on the order of carrier detection time) and is independent of the end-to-end network propagation delay. This improvement is particularly significant when the channel data rate is so high, or the end-to-end propagation delay is so large, or the packet size is so small as to render the end-to-end propagation delay a significant fraction of, or larger than, the transmission time of a packet. Moreover, some features of the present invention make it particularly suitable for voice applications. In view of integrating voice and data, a voice/data protocol is described which allows it to meet the bandwidth requirement and maximum packet delay constraint for voice communication at all times, while guaranteeing a minimum bandwidth requirement for data traffic. The voice/data protocol constitutes a highly adaptive allocation scheme of channel bandwidth, which allows data users to steal the bandwidth unused by the voice application.