Conference Paper

Three scheduling-levels algorithm for IEEE 802.11 QoS efficiency improvement

DOI: 10.1145/1497185.1497211 Conference: MoMM'2008 - The 6th International Conference on Advances in Mobile Computing and Multimedia, 24 - 26 November 2008, Linz, Austria
Source: DBLP


This paper focuses on an analysis of the packets scheduling schemes to improve the QoS in IEEE 802.11 WLANs. Based on the Hybrid Coordination Function (HCF) at the MAC layer, a new algorithm structure called HCF-T is proposed. It is centralized in three process units for both packets scheduling and Transmission Opportunities (TXOPs) allocating main tasks. Taking into account the queue length as relevant information, the scheduling strategy tracks the queue's contents and manages the packets enabling TXOPs duration to be well assessed. We investigate the effectiveness of the new mechanism by developing a simulation model. In this regard, the evaluation of performances is carried out in terms of traffic control frames, collisions, and network load. Finally, we discussed some remarks related to cooperative diversity networks and planning the upcoming work.

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