The scheduled-retransmission multiaccess (SRMA) protocol for packet satellite communication

摘要

An improvement of the announced retransmission random access (ARRA) protocol for packet satellite communication, called the scheduled retransmission multiaccess protocol, is introduced. Besides avoiding collision between new and retransmitted packets, the improved protocol eliminates reservation conflicts between different slots. Explicit acknowledgement is used, so that traffic to other zones served by the same satellite can also be accommodated. Assuming that 3% of the channel capacity is used for retransmission reservation, fixed frame and dynamic-frame SRMAs achieve effective maximum throughputs of 0.65 and 0.89, respectively. Both protocols give average delays considerably lower than slotted ALOHA, even when the throughput is as low as 0.2.