In typical urban environments, residential users usually see many 802.11 gateways in range with high quality (see figure), and these gateways are commonly connected to broadband links such as ADSL and cable. At home, the users are not limited by their wireless speed (which typically ranges from 54 Mbps up to 450 Mbps), but by their ADSL and cable speeds (in the range of 3 – 12 Mbps). This is particularly true in the case of uplink speeds, which rarely surpass 1 Mbps in Europe. Moreover, it is well known that these broadband links are underutilized, so they have plenty of bandwidth to spare. In this scenario, if we could simultaneously connect to all the neighboring WiFi gateways and use the spare bandwidth of our neighbors, we could dramatically improve our downlink and uplink speeds without impacting the quality of service of the line owners.In typical urban environments, residential users usually see many 802.11 gateways in range with high quality, and these gateways are commonly connected to broadband links such as ADSL and cable. At home, the users are not limited by their wireless speed (which typically ranges from 54 Mbps up to 450 Mbps), but by their ADSL and cable speeds (in the range of 3 – 12 Mbps). This is particularly true in the case of uplink speeds, which rarely surpass 1 Mbps in Europe. Moreover, it is well known that these broadband links are underutilized, so they have plenty of bandwidth to spare. In this scenario, if we could simultaneously connect to all the neighboring WiFi gateways and use the spare bandwidth of our neighbors, we could dramatically improve our downlink and uplink speeds without impacting the quality of service of the line owners.

 

But aggregating the backhauls is not enough: since there could be a potential high number of users sharing their broadband links, there must be a practical way of imposing some fairness into the system. Without fairness, the perceived value of the system is severely reduced, eliminating the incentives of users to participate, and of providers to deploy it. This effectively renders the scheme infeasible.

 

Motivated by this problem, we developed ClubWiFi, a single-radio station that performs multi-gateway backhaul aggregation in a fair and distributed way, without requiring any change in the network. ClubWiFi uses a single radio WiFi card, hence working in most of the existing hardware. With ClubWiFi, the users always have their own bandwidth at home guaranteed, ensuring that the performance is always equal or better than not using ClubWiFi. Moreover, the system provides per-client fairness when several users try to share spare bandwidth of their neighbors. In this way, the users have always an incentive to participate.

 

We thoroughly evaluated the performance of ClubWiFi through controlled experimental tests and validated it in a deployment spanning several floors of a multistory building. We show that it achieves high aggregate throughput over the connecting gateways, and seamlessly transmits TCP traffic under realistic scenarios. In fact, Telefónica is currently piloting the ClubWiFi technology in a pre-commercial trial in several countries in Latin America.