Not terribly surprising news today that Telstra is to invest $100M is building "public" WiFi.
Well, it is not really public WiFi - it is a WiFi network open to all Telstra subscribers. In doing so it is partnering with Fon which advertises it has over 12 million WiFi points. The process is easy - because the network piggy-backs off all their customers private connections and uses duplicate SSID's - one for the customer's own network and one for the WiFi.
Telstra will not use a line if it isn't providing better than 3 Mbps.
This is not a new development - as shown by Fon's base. By partnering with Fon Telstra is opening up access to that network for its customers.