AT&T may be adapting a new protocol to relieve pressure on its 3G network, reports say. The 802.21 protocol may be responsible for the new prompt-free process of automatically transitioning an iPhone from 3G to one of AT&T's Wi-Fi hotspots. The technology is designed to switch to and from cellular, Wi-Fi, Bluetooth, 802.11 and 802.16 networks using handover algorithms.