Distributed channel assignment in multi-radio 802.11 mesh networks

Abstract — 802.11 wireless mesh networks are an attractive alternative to wired local and metropolitan area networks. To increase the utilization of the 802.11 spectrum in these environments, recent work has explored how to utilize the entire 802.11 spectrum when transmitting data through the mesh network. This paper reports on our design of a distributed, self-stabilizing protocol that assigns channels to mesh nodes in large-scale mesh networks. We demonstrate the efficacy of our protocol on a realworld, 14-node testbed comprised of nodes, each equipped with an 802.11a card and an 802.11g card. We show via extensive measurments on our testbed that our channel assignment algorithm improves the network capacity by 50 % in comparison to a homogeneous channel assignment and by 20 % in comparison to a random assignment. Furthermore, our protocol provides particular benefit to flows over long paths which would otherwise suffer poor end-to-end performance due to wireless interference. I