Performance issues with routing in multi-channel multi-interface IEEE 802.11s networks

Wireless Mesh Networks have the potential to serve as an all-wireless backbone. They represent a key building block of the new Internet of Things to collect all the traffic. However, IEEE 802.11 performs very poorly in multi-hop topologies leading to unfairness and a poor throughput. Thus, the standard IEEE 802.11s proposes to re-use the IEEE 802.11 medium access in a mesh multi-hop topology while using a routing protocol to create routes at the layer 2. IEEE 802.11s may exploit multi-channel multi-interface wireless routers to increase the through-put. In particular, the routing protocol must select carefully the forwarders to limit inter- and intra-flow interference. In this paper, we propose to fully characterize the performance of IEEE 802.11s when using multi-interface nodes, and to isolate some key performance issues. We also propose some key mechanisms that must be implemented to solve these pathological cases and to improve the throughput.