IEEE 802.11s Wireless Mesh Networks for Last-mile Internet Access: An Up- Down Link

Being multi-hop wireless networks, Wireless Mesh Networks (WMNs) are witnessing limited network capacity, mainly due to the contention among nodes in multi-hop paths. Several techniques have been proposed to cope with the limitation, e.g., using multi-channels. These techniques, however, do not account for the very specificity of traffic flow in WMNs when used for last-mile Internet access. In this paper, we propose a multi-channel scheme that mitigates the network capacity limitation by accounting for the nature of traffic direction. This latter is mostly flowing towards/from the gateway connecting the WMN to the Internet, and forms a tree with the gateway as a root. The scheme assigns two separate interfaces/channels: one for communicating traffic coming/going from/towards nodes up in the tree and the other for communicating traffic coming/going to nodes down in the tree. Using extensive simulations, and using non-overlapping IEEE 802.11g channels, we show that our scheme improves the network capacity by 33 % in two-hop WMNs, and by 508 % in three-hop WMNs