Modeling of IEEE 802.11e Contention Free Bursting Scheme with Heterogeneous Stations

Contention free bursting (CFB) is an innovative quality-of-service (QoS) scheme specified in the IEEE 802.11e standard. To reduce the contention overheads, this scheme enables the stations that gain the channel to transmit multiple frames back-to-back in a burst. Most existing analytical models of the CFB scheme have been developed under the assumption of identical stations with saturated traffic loads. In this paper, we present an analytical model for investigating the performance metrics of throughput, end-to-end delay, loss probability, and energy consumption of the CFB scheme in the presence of nonidentical stations with different traffic generation rates. The model is validated against extensive ns2 simulation experiments. Numerical performance results demonstrate the efficiency of the CFB scheme for improving the network performance.