Bittorrent traffic optimization in Wireless Mesh Networks with ALTO service

Wireless Mesh Networks (WMNs) have recently gained wide attention as a way to provide Internet connectivity in hard-to-reach areas as well as in big cities. The main problem of such networks is their limited bandwidth availability compared to wired networks. Hence, efficient usage of available communication resources is of crucial importance for WMNs. Peer-to-peer applications, these days, produce a considerable amount of traffic over the Internet. Such applications build their own overlay network by not taking into account the topology and the status of the underlying infrastructure, so causing an inefficient utilization of physical communication resources. This problem is particularly severe for Wireless Mesh Networks. In this paper we propose a cross-layer solution for P2P Bittorrent traffic optimization in WMNs, based on the ALTO (Application Layer Traffic Optimization) Service recently defined by the IETF. Our solution is able to significantly optimize Bittorrent traffic and it does not require any modification to the Bittorrent application. The tests we performed show a reduction of about 27% of download time and a reduction of about 66% of traffic crossing the WMN borders.