Fair Scheduling Mechanisms with QoS Consideration for the IEEE 802.11e Wireless LAN

Two scheduling mechanisms called enhanced distributed deficit round robin with backoff interval (EDDRR-BI) and enhanced distributed elastic round robin with backoff interval (EDERR-BI) are proposed in this paper for the IEEE 802.11e wireless LAN. EDDRR-BI and EDERR-BI take both priority which is a mean to guarantee quality of service (QoS) and fairness simultaneously into account so that QoS and fairness can be well taken care. The idea behind the proposed mechanisms mainly relies on dynamic adjustment of the backoff interval according to priority, collision rate, and deficit count or allowance. Through numerical experiments, we demonstrate that the proposed mechanisms can reach station-level fairness as well as flow-level fairness within the same (among different) access category (categories). Of course, these mechanisms outperform the related schemes in the literature.