Traffic differentiation and QoS provisioning for IEEE 802.11e wireless LAN

摘要

In 802.11e wireless local area network (WLAN), MAC protocol is very much essential for offering multimedia quality of service (QoS) to WLAN users in terms of metrics like throughput, data drop, fairness and medium access delay. In addition, MAC protocol must be suitable for both user datagram protocol (UDP) and transmission control protocol (TCP) flows. In this paper, we propose a traffic differentiation and QoS provisioning technique based on DiffServ architecture for IEEE 802.11e WLAN. When a new flow arrives, it is initially provisioned with QoS using DiffServ engine. The output is fed to traffic differentiator that differentiates the traffic frames as UDP flows or TCP flows. If the distinguished traffic frame is UDP, then its contention window (CW) will be adjusted according to number of active uplink and downlink flows. If the distinguished traffic frame belongs to TCP, then CW will be adjusted according to the number of idle slots between two consecutive transmissions. Results indicate fair resource allocation and improved performance when compared to the other existing system.