Generic Access Network (GAN) - Definition
The Generic Access Network (GAN), also known as Unlicensed Mobile Access (UMA), is a telecommunication system allowing seamless roaming and handover between local area networks and wide area networks using a dual-mode mobile phone. It lets mobile operators deliver voice, data and IP Multimedia Subsystem/Session Initiation Protocol (IMS/SIP) type applications to mobile phones. Its ultimate goal is the convergence of mobile, fixed and Internet telephony (Fixed Mobile Convergence).
The local network may be based on private unlicensed spectrum technologies like Bluetooth or 802.11, while the wide network is alternatively GSM/GPRS or UMTS mobile services. On the cellular network, the mobile handset communicates over the air with a base station, through a base station controller, to servers in the core network of the carrier. Under the GAN system, when the handset detects a LAN, it establishes a secure IP connection through a gateway to a server called a GAN Controller (GANC) on the carrier's network. The GANC translates the signals coming from the handset to make it appear to be coming from another base station. Thus, when a mobile moves from a GSM to a Wifi network, it appears to the core network as if it is simply on a different base station. The system was initially called UMA and then renamed to GAN. It was developed by a group of operator and vendor companies.
FMC networks, based on the IMS framework, contain a horizontal control layer that isolates the access network from the service layer.
Generic Access Network (GAN)- Synonyms
Generic Access Network; GAN; Unlicensed Mobile Access; UMA