Evaluation of QoS support for multimedia traffics in IEEE 802.11e

The efficient delivery of multimedia over wireless LANs is strongly dependent on the requirements imposed by different traffics contending the channel resources. Mechanisms for supporting QoS are needed, especially when voice and video applications come into play with stringent constraints in terms of delay and throughput. In this paper we evaluate, through simulations, the benefits derived from the adoption of the IEEE 802.11e standard in delivering multimedia over WLANs. The adoption of fine-tuned parameters regulating the EDCA MAC scheme permits to achieve high performance in terms of goodput and delay, allowing multimedia traffics to fully satisfy their QoS requirements. Realistic assumptions have been made in our simulations, by taking into account the shadowing effects, typical of closed environments, and by adopting suitable parameters to simulate 802.11e channels as exactly as possible.