Question: how does btwifi with fon work?
Answer: Since March 2009, all new BT Broadband customers are automatically members of the Fon community and agree to securely share a portion of their wi-fi bandwidth through a separate channel on their hub. ... That's over 20 million wi-fi hotspots around the world. Participating BT Hubs are known as BTWifi-with-Fon hotspots.