carrier Wi-Fi

carrier Wi-Fi

The deployment of a large number of Wi-Fi access points in dense geographic areas by a cellular carrier in order to augment its cellphone network. All mobile devices have Wi-Fi, and the capability of offloading cellular traffic to Wi-Fi eliminates cellular congestion. The cellular carrier may also be able to generate additional revenue with a Wi-Fi hotspot plan added on top of the regular data plan.

Phones Already Switch to Wi-Fi
If Wi-Fi is detected that is already in the phone's hotspot list, or even if not (see Wi-Fi Passpoint), the phone will connect to Wi-Fi for data rather than continue to use the cellular network.