A little sharing goes a long way: The case for reciprocal Wifi sharing

Widespread deployment of private home Wifi access points (APs) can result in uncoordinated and overlapping wireless networks that compete with each other for limited bandwidth. We expect this suboptimal arrangement to only get worse, particularly in the dense urban environments that house an increasing fraction of the world's population. Broadband penetration and the demand for high-speed Wifi throughout at home will lead to more private APs, which will generate more interference for neighboring networks, resulting in even more private APs and additional interference, and so on. In this paper we investigate whether we can prevent this vicious cycle by using reciprocal Wifi sharing to make better use of existing private home APs. We define reciprocal Wifi sharing as cases where two users both improve their network performance by connecting to each other's overlapping private Wifi networks. Compared to previous approaches that attempted to use private APs to create large-scale open-access Wifi networks, reciprocal Wifi sharing relationships more closely mirror existing human relationships and can be maintained without elaborate reputation mechanisms. To evaluate the potential for reciprocal Wifi sharing, we analyze 21 M Wifi scans collected from 254 smartphones over 5 months. Our results show that even in a sparsely-populated suburban area, reciprocal Wifi sharing can be beneficial. And surprisingly, we detected several reciprocal Wifi sharing opportunities even within our tiny user sample. Motivated by these results, we present the design of WISEFI, a system enabling reciprocal Wifi sharing.