31-08-2017, 11:11 AM
Generic Access Network or GAN is a telecommunications system that extends mobile voice, data and multimedia applications (IMS / SIP) over IP networks. Unlicensed Mobile Access or UMA is the business name used by mobile companies for external IP access to their primary networks. The next generation system is called Wi-Fi Calling by several handset manufacturers, including Apple and Samsung, a move that is being reflected by companies like T-Mobile US.
Essentially, GAN allows cell phone packets to be forwarded to a network access point via the Internet, rather than over-the-air using GSM / GPRS, UMTS or the like. A separate device known as a "GAN Controller" (GANC) receives this data from the Internet and enters it into the telephone network as if it came from an antenna in a tower. Calls can be placed from or received in the phone as if they were connected by air directly to the GANC point of presence. The system is essentially invisible to the network as a whole.
In its most common form, the GAN is used to allow UMA-enabled mobile phones to use WiFi networks to connect calls, rather than conventional cell towers. This can be useful in locations with poor cellular coverage, where some other form of Internet access is available, especially at home or office. The system offers uninterrupted transfer, so the user can switch from cell to WiFi and again with the same invisibility offered by the cellular network when moving from tower to tower.
Because the GAN works over the Internet, a UMA-capable phone can connect to your service provider from anywhere with Internet access. This is particularly useful for travelers, who can connect to their provider's GANC and make calls in their home service area from anywhere in the world. This is subject to the quality of the Internet connection, however, and may not work well over limited bandwidth or long latency connections. To improve the quality of service in the home or office, some providers also provide a specially programmed wireless access point that prioritizes UMA packets.
Essentially, GAN allows cell phone packets to be forwarded to a network access point via the Internet, rather than over-the-air using GSM / GPRS, UMTS or the like. A separate device known as a "GAN Controller" (GANC) receives this data from the Internet and enters it into the telephone network as if it came from an antenna in a tower. Calls can be placed from or received in the phone as if they were connected by air directly to the GANC point of presence. The system is essentially invisible to the network as a whole.
In its most common form, the GAN is used to allow UMA-enabled mobile phones to use WiFi networks to connect calls, rather than conventional cell towers. This can be useful in locations with poor cellular coverage, where some other form of Internet access is available, especially at home or office. The system offers uninterrupted transfer, so the user can switch from cell to WiFi and again with the same invisibility offered by the cellular network when moving from tower to tower.
Because the GAN works over the Internet, a UMA-capable phone can connect to your service provider from anywhere with Internet access. This is particularly useful for travelers, who can connect to their provider's GANC and make calls in their home service area from anywhere in the world. This is subject to the quality of the Internet connection, however, and may not work well over limited bandwidth or long latency connections. To improve the quality of service in the home or office, some providers also provide a specially programmed wireless access point that prioritizes UMA packets.