Adaptive multihop scheduling for IEEE 802.11s multiradio cognitive wireless mesh networks

Wireless mesh networks (WMN) are efficient and low cost solutions for the deployment of broadband access in various environments. To support real-time applications such as multimedia and emergency services throughout the network, WMNs must provide appropriate quality of service (QoS). While the capacity and the bandwidth availability of single radio WMNs may severely limit QoS for such traffic, multiradio cognitive WMNs (CWMN) can overcome these restrictions and provide better QoS mechanisms. This paper describes a scheduling algorithm with an integrated backpressure mechanism for CWMN. This algorithm ensures that the available bandwidth is properly shared considering the type of traffic to forward, the distance of the clients from the portal and the fluctuating conditions of the links. The performance of our new scheduling algorithm is evaluated in a simulated environment. We show that, while increasing throughput, our algorithm not only achieves nearly perfect fairness, but can also prevent bandwidth wastage.