UMA (Unlicensed Mobile Access) / Generic Access Network (GAN)
UMA, a 3GPP (3rd Generation Partnership Program) standard, is an access technology that allows seamless handover of mobile voice and data from a cellular network to a wireless local area network (WLAN/WiFi). The UMA standard defines how mobile operators can turn home, office and public WLANs into seamless extensions of their cellular networks. With UMA, operators can deliver voice and data services to subscribers over the WiFi access networks, dramatically increasing mobile service usage while decreasing costs of network deployment.