Performance Analysis of IEEE 802.11e WLANs with Hidden Stations and Heterogeneous Traffic

IEEE 802.11e Medium Access Control (MAC) mechanism has been recently proposed for supporting differentiated Quality-of-Services (QoS) in Wireless Local Area Networks (WLANs). Heterogeneous traffic generated by wireless multimedia applications and hidden stations arisen from the wireless transmission power constraints have significant impact on the performance of MAC protocols. This study performs extensive simulation experiments and conducts comprehensive performance evaluation of the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) protocol in WLANs with hidden stations and heterogeneous traffic. For this purpose, non-bursty Poisson, bursty ON/OFF, and fractal-like self-similar processes with high variability are used to model and generate heterogeneous network traffic. The performance results have shown that the protocol is able to achieve differentiated throughput, access delay and medium utilization. However, the hidden stations can degrade the throughput and medium utilization and also increase the medium access delay greatly in the presence of heterogeneous traffic.