Performance analysis of CSMA with priority acknowledgments (CSMA/PA) on noisy data networks with finite user population

An analytical procedure is developed to calculate delay and throughput performance of CSMA/PA (carrier sense multiple access with priority acknowledgments). Time-axis slotting and Markov chain analysis are used to determine the channel backlog per cycle. A cycle includes information packet access and transmission time followed by acknowledgment transmission or time-out. Throughput and delay performance are then calculated in terms of the number of network terminals, the network packet error probability, the packet generation rate, and the mean information packet retransmission delay. Fixed-length information and acknowledgment packets are assumed. Calculated results show excellent agreement with measured delay and throughput performance for two distinct five-node intrabuilding power line networks operating at data rates from 1.2 to 9.6 kb/s