That's not completely correct, WiMAX is a standards based technology, if you deliver a true WiMAX product it better work with anyone's network supporting WiMAX or you can't call it WiMAX; the question comes down to the frequency range being used by the provider which will determine if you can interconnect with a WiMAX signal. Of course actually getting access to a network will be similar to how many Wi-Fi hotspots work today where there may or may not be an authentication mechanism used to gain access to the internet.