Priority-based parameter performance optimization for EDCA

The IEEE 802.11 working group released the IEEE 802.11e protocol to provide QoS for different transmission business. The analysis of the EDCA mechanism in the IEEE 802.11e is made for the purpose of improving the network transmission performance and the QoS of the EDCA mechanism under different network load conditions. The focuses of this article are three priority parameters (AIFS, CW_min and CW_max, TXOP) of the EDCA mechanism. In this paper, with the help of the NS2 software, we build a simulation environment in which the simulation contrast tests of each priority parameter are made at first. Then we observe in different network load conditions that the effect of each priority parameter has on the network transmission performance and QoS. Finally, based on the analysis of simulation results, we conclude that the network performance of EDCA and QoS can be enhanced by two means: adjusting the parameters to reduce the waiting time in low-load circumstances while varying the parameters to minimize the conflicting time in heavy-load conditions.