A comprehensive analysis of IEEE 802.11 DCF heterogeneous traffic sources

Among the IEEE 802.11 models proposed in the literature most concentrate solely on homogeneous traffic sources (i.e., with the same arrival rate) and there are only a few which concentrate on heterogeneous nonsaturated traffic sources. This paper proposes a comprehensive analysis of heterogeneous traffic sources (saturated or nonsaturated) with M/M/1/K queues. The mathematical model proposed in this paper allows the calculation of the following parameters: per-station and network throughput, delay (including service time and queuing delay), and frame loss probability (including probability of dropping a frame at the MAC layer and in a transmission queue). Simulation results show the impact of the presence of different traffic source types on each other and validate the correctness of the proposal for a variable number of stations and under different network loads. Importantly, the new model is kept reasonably simple to attract network designers. We provide examples of its practical applicability by performing an estimation of the maximum number of voice calls which can be accepted by a particular network and the optimal buffer size.