Output Processes in Contention Packet Broadcasting Systems

The processes consisting of the packet interdeparture times in contention-type packet broadcasting systems are studied under the heavy-traffic assumption. The channel access protocols considered include slotted and unslotted ALOHA and carrier-sense-multiple-access (CSMA) with and without collision detection. Through analysis of the Channel activity cycle, the distribution, mean, and coefficient of variation of the packet interdeparture times are explicitly derived. Taking the reciprocal of the mean interdeparture time, we obtain the channel throughput. Cases with dissimilar users are mainly considered, and systems of statistically identical users are treated as special cases.