A MAC-layer differentiated service model in IEEE 802.11e WLANs

In this paper, we provide a differentiated service model in IEEE 802.11e wireless local area networks (WLANs). In our service model, a new mechanism called differentiated service - EDCA (DS-EDCA) is proposed to provide both strict priority and proportional fair service for IEEE 802.11 WLANs. The EDCA parameter set of lower priority traffic is carefully designed, and the backoff intervals are determined according to the distributed scheduling discipline DFS. Furthermore, a hierarchical link sharing model is proposed for IEEE 802.11e WEANs, which allocates different amount of link resource for AP and mobile stations. The performance of DS-EDCA and EDCA is compared via ns-2 simulations. The results show that DS-EDCA outperforms the original EDCA in terms of the support for both strict priority and weighted fair service. Most importantly, DS-EDCA can be easily implemented, and is compatible to the IEEE 802.11 standard