Throughput and Delay Analysis for p-Persistent CSMA with Heterogeneous Traffic

CSMA/CA is a common access mechanism for contention based wireless channels. One of the ways in which quality of service in contention based wireless networks is achieved is by service differentiation. This can be realised by prioritising packets based on their importance while taking into account the network load. p-persistent CSMA is a form of CSMA/CA and in this paper an analytical model for the throughput and delay of a p-persistent CSMA system is developed where the system contains a finite number of non-saturated stations with both heterogeneous loads and priorities. Results based on this new model show how the throughput and delay for the traffic flows on the network are affected by the relative p-persistence and offered load values for all of the stations in the network.