12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Adaptive fair channel allocation for QoS enhanc...
View graph of relations

« Back

Adaptive fair channel allocation for QoS enhancement in IEEE 802.11 wireless LANs

Research output: Contribution in Book/Report/ProceedingsPaper

Published

Publication date2004
Host publicationCommunications, 2004 IEEE International Conference on
Place of publicationNew York
PublisherIEEE
Pages3470-3475
Number of pages6
ISBN (Print)0780385330
Original languageEnglish

Conference

ConferenceIEEE International Conference on Communications (ICC 2004)
CityParis
Period20/06/0424/06/04

Conference

ConferenceIEEE International Conference on Communications (ICC 2004)
CityParis
Period20/06/0424/06/04

Abstract

The emerging widespread use of real-time multimedia applications over wireless networks makes the support of Quality of Service (QoS) a key problem. In this paper, we focus on QoS support mechanisms for IEEE 802.11 Wireless ad-hoc networks. First, we review limitations of the upcommig IEEE 802.11e Enhanced DCF (EDCF) and other enhanced MAC schemes that have been proposed to support QoS for 802.11 ad-hoc networks. Then, we describe a new scheme called adaptive fair EDCF that extends EDCF, by increasing the contention window during deferring periods when the channel is busy, and by using an adaptive fast backoff mechanism when the channel is idle. Our scheme computes an adaptive backoff threshold for each priority level by taking into account the channel load. The new scheme significantly improves the quality of multimedia applications. Moreover, it increases the overall throughput obtained both in medium and high load cases. Simulation results show that our new scheme outperforms EDCF and other enhanced schemes. Finally, we show that the adaptive fair EDCF scheme achieves a high degree of fairness among applications of the same priority level.