Performance Evaluation of Real-Time Application for EDCA Function in IEEE 802.11e WLAN

The IEEE 802.11 standard is a widely used base for wireless local area network (WLAN) infrastructure, because of its easy deployment. But it cannot provide QoS support for an increasing number of multimedia applications. With deployment of WLAN, the ability of the IEEE802.11 standard to support multimedia applications with high quality of service (QoS) requirements has increased. This paper evaluates the capacity of QoS support in Enhanced Distributed Channel Access (EDCA) mechanism of the IEEE 802.11e standard. The EDCA is an enhancement for QoS support in 802.11. EDCA mechanisms allow prioritized medium access for applications with high QoS requirements by assigning different priorities to the access categories. This paper discusses the performance limitation of 802.11e and 802.11. The parameters delay and throughput are discussed in two different scenarios. A comparative discussion between DCF und EDCA is constituted for different services, such as voice, video, best-effort and background traffic. The simulation results show the QoS support of 802.11e standard for different types of data traffic due to its service differentiation technique. With EDCA mechanism, network capacity is effectively increased and the support for multimedia applications transmissions is improved.