Study of Quality of Service by using 802.11e

Wireless Local Area Networks (WLANs) are one of the fastest growing wireless access technologies. The IEEE 802.11 Standard doesn’t support any QoS mechanisms. IEEE 802.11 MAC layer supports two basic access mechanisms, DCF (Distributed Coordination Function) and PCF (Point Coordination Function). The EDCA mechanism of the IEEE 802.11e standard provides QoS support through service differentiation, by using different MAC parameters for different access Categories. IEEE 802.11e uses three parameters that is TXOP, AIFS, CWmin and CWmax for providing QoS. In this paper service differentiation ability of IEEE 802.11e is evaluated. Parameters of the IEEE 802.11e are statically tuned to achieve optimum performance in different environments. Network Simulator2 (NS2) is used for simulation.