Dynamic Priority Scheduling Mechanism through Adaptive InterFrame Space

The increasing demand of multimedia applications in wireless local area networks (WLAN) has led to the attempt to provide quality of service for differentiated traffics in WLAN. In this paper, a novel mechanism, Adaptive IFS through Transmission Delay (AITD) is introduced; to dynamically adjust the inter-frame space (IFS) based on differentiation between required transmission delay and estimated experienced transmission delay. Depending on the network conditions and source requirements, increase in experienced transmission delay toward expected transmission delay leads to dynamic reduction in IFS length and increase in transmission probability. Simulation results show that the proposed mechanism can significantly improve the scheduling performance in comparison with enhanced distributed coordination function introduced in IEEE802.11e.