Distributed protocols for access arbitration in tree-structured communication channels

The problem of arbitrating access to a tree-structured communication channel with large geographic extent, providing multipoint communication among a set of terminals, is considered. In the model used, terminals transmit information in bursts consisting of many packets and compete for the right to transmit bursts. In the simplest case, the channel allows only one terminal to transmit at a time; this can be extended to k concurrent transmitters. The problem resembles contention resolution in local are networks. It is distinguished by the topology of the channel, the magnitude of the delays involved, and the potential for multiple transmitters. Two general approaches are identified, as well as several specific access-arbitration algorithms. A preliminary assessment is given of their promise.<>