Error Control for Multicasting in Satellite and Hybrid Communication Networks

Title of Dissertation: Error Control for Multicasting in Satellite and Hybrid Communication Networks Daniel E. Friedman, Doctor of Philosophy, 2000 Dissertation directed by: Professor Anthony Ephremides Department of Electrical Engineering A problem inherent in ARQ multicasting over a broadcast channel is that a retransmission typically benefits only a minority of destinations while all others wait unproductively. This results in poor throughput to each receiving station in the network, with the throughput diminishing as the number of receivers grows. If point-to-point links between the transmitter and each receiver were also available, then conceivably retransmissions could be sent over such secondary links. This would reduce the frequency of retransmissions interrupting the flow of new packets on the broadcast link. That is, a hybrid satellite-terrestrial network architecture would allow greater throughput for multicasting than a pure-satellite network. This work examines ARQ multicasting in such a network, and confirms by analysis and simulation that, within limits, such a throughput advantage can be realized. A detailed discussion of implementation aspects for point-to-point and point-tomultipoint ARQ protocols in both pure-satellite and hybrid networks is presented as well. This work also considers partitioning a fixed amount of bandwidth to maximize throughput, possibly subject to a cost constraint, and the effect of a “poor listener” upon performance in both pure-satellite and hybrid networks.