I wrote previously (here) about being connected to cellular networks indoors without the need of a dual-mode handset using a technology called Femtocells. Another technology is also soon to be available that will connect both the wide area networks (the cellular networks like GSM/GPRS/UMTS) with a local area network (Wi-Fi). This technology is called UMA (Unlicensed Mobile Access) also known as Generic Access Network (GAN) and it allows the user to use one handset (dual-mode) and one number to connect to both networks.

While the mobile user is connected to a cellular network it scans the area for a Wi-Fi signal. Once detected, it establishes a secure IP connection to a server on the carrier’s network  (ref: wikipedia) and the mobile user is handed-off from the cellular network to the Wi-Fi network.

Cellular operators prefer the Femtocell tehcnology since UMA uses the unlicensed Wi-Fi networks which allows the user to use the internet for data and voice calls. As we know, making a VoIP phone call is alot cheaper than using the cellular network. Maybe cellular operators should lower the costs of voice calls and offer a good Femtocell plan to attract users, since a high number of those users actually use their cell phones indoors.