Patent ID: 7039027

Claim:
A system for automatic and seamless vertical roaming (SVR) between a wireless local area network (WLAN) and a wireless wide area network (WWAN) while maintaining an active voice or data communication comprising: (a) a mobile station for WWAN and WLAN transmissions to the WLAN and the WWAN network; (b) a WLAN gateway linked to the mobile station by a WLAN bi-directional communication link and operating in the Global System Mobile (GSM)/General Packet Radio Service (GPRS) or IEEE 802.11 modes; (c) a base transceiver station operating in the GSM GPRS modes for servicing the WWAN and linked to the mobile station by a WWAN bi-directional communication link; (d) a switched network including a mobile switching center connected to the WLAN gateway and the base transceiver station; and (e) WLAN command apparatus to initiate transfer of traffic between the mobile station and a remote user on the WLAN via the gateway to the WWAN when signal degradation occurs.