A congestion control scheme for layer 3 wireless mesh networks

In a wireless mesh network (WMN) connected to the outer infrastructure such as the Internet, one or more gateways to connect to the outer network as well as surrounding nodes may frequently be congested by concentration of traffic from mobile stations. To resolve the congestion, we propose a new congestion control scheme for layer 3 WMNs. In the proposed scheme, nodes composing WMN backbone (MNs: mesh nodes) monitor their transmission queue periodically and detect congestion. When an MN detects congestion, it identifies MNs which inject a dominant amount of traffic causing congestion, and sends a congestion control message to these MNs. When the MNs receive the congestion control message, they control the bandwidth of the traffic toward the congested MN. We have performed simulation of the proposed scheme using a simple network model and evaluated the effect of congestion control. We have shown that the proposed method is effective to reduce average queue length of the bottle-neck MN and to improve the total throughput significantly.