Performance analysis for IEEE 802.11e EDCF service differentiation

Having been originally developed as an extension of the wired local area networks, IEEE 802.11 lacks support for quality-of-service (QoS) and differential services. Since its introduction, various extensions and modifications have been studied to address this current need and the IEEE 802.11 Task Group E is responsible for developing a QoS-aware MAC protocol that considers several service differentiation mechanisms. However, the performance of service differentiation has only been evaluated by simulation. The analytical model that calculates the differential service performance corresponding to the contention parameter configuration has not been found yet. In this paper, we first briefly explain the enhanced distributed coordination function (EDCF) access method of IEEE 802.11e. We then introduce an analytical model, which can be used to calculate the traffic priority, throughput, and delay corresponding to the configuration of multiple DCF contention parameters under the saturation condition. A detailed simulation is provided to validate the proposed model. Finally, using the analytical model, we analyze the effect on service differentiation for each contention parameter. The contention parameters can be configured appropriately at each station to achieve specific needs of service differentiation for applications.