DocumentCode :
1193002
Title :
Supporting QoS in IEEE 802.11e wireless LANs
Author :
Chen, Xiang ; Zhai, Hongqiang ; Tian, Xuejun ; Fang, Yuguang
Volume :
5
Issue :
8
fYear :
2006
Firstpage :
2217
Lastpage :
2227
Abstract :
In the emerging IEEE 802.11e MAC protocol, the enhanced distributed channel access (EDCA) is proposed to support prioritized QoS; however, it cannot guarantee strict QoS required by real-time services such as voice and video without proper network control mechanisms. To overcome this deficiency, we first build an analytical model to derive an average delay estimate for the traffic of different priorities in the unsaturated 802.11e WLAN, showing that the QoS requirements of the real-time traffic can be satisfied if the input traffic is properly regulated. Then, we propose two effective call admission control schemes and a rate control scheme that relies on the average delay estimates and the channel busyness ratio, an index that can accurately represent the network status. The key idea is, when accepting a new real-time flow, the admission control algorithm considers its effect on the channel utilization and the delay experienced by existing real-time flows, ensuring that the channel is not overloaded and the delay requirements are not violated. At the same time, the rate control algorithm allows the best effort traffic to fully use the residual bandwidth left by the real-time traffic, thereby achieving high channel utilization
Keywords :
access protocols; channel allocation; quality of service; telecommunication congestion control; telecommunication traffic; wireless LAN; IEEE 802.11e wireless LAN; MAC protocol; QoS; call admission control schemes; channel busyness ratio; channel utilization; enhanced distributed channel access; rate control scheme; real-time traffic; Access protocols; Admission control; Analytical models; Call admission control; Communication system traffic control; Delay effects; Delay estimation; Media Access Protocol; Traffic control; Wireless LAN;
fLanguage :
English
Journal_Title :
Wireless Communications, IEEE Transactions on
Publisher :
ieee
ISSN :
1536-1276
Type :
jour
DOI :
10.1109/TWC.2006.1687738
Filename :
1687738
Link To Document :
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