UMA (Unlicensed Mobile Access) or GAN (Generic Access Network) makes it possible to seamless handover between GSM (Global System for Mobile Communications) and WLAN (Wireless Local Area Networks). Wi-Fi (Wireless Fidelity) based on IEEE 802.11 specifications uses one or more Wireless Access Point(s) (WAP) and one or more clients which can connect to the Internet when in proximity of an access point. Wi-Fi is ideal for VoIP (Voice over Internet Protocol). So what’s all the fuss? The definite death of the ‘old school’ conventional fixed landline telephone. Services like Skype already challenged the landline telephones, but has one major disadvantage: you must have the Skype software installed and running on your computer. UMA will solve this! Mobile phone developers will create phones with this feature (Nokia and Samsung already have proof of concept). Operators will implement and offer base station units. You can call with the same mobile phone indoor with VoIP, outdoor over a GSM network.