Wi-Fi calling

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It has been suggested that Voice over WLAN be merged into this article. (Discuss) Proposed since May 2024.

Wi-Fi calling, also called VoWiFi,^[1] refers to mobile phone voice calls and data that are made over IP networks using Wi-Fi, instead of the cell towers provided by cellular networks.^[2] Using this feature, compatible handsets are able to route regular cellular calls through a wireless LAN (Wi-Fi) network with broadband Internet, while seamlessly change connections between the two where necessary.^[3] This feature makes use of the Generic Access Network (GAN) protocol, also known as Unlicensed Mobile Access (UMA).^[4][5]

Essentially, GAN/UMA allows cell phone packets to be forwarded to a network access point over the internet, rather than over-the-air using GSM/GPRS, UMTS or similar. A separate device known as a "GAN Controller" (GANC)^[5] receives this data from the Internet and feeds it into the phone network as if it were coming from an antenna on a tower. Calls can be placed from or received to the handset as if it were connected over-the-air directly to the GANC's point of presence; the system is essentially invisible to the network as a whole.^{[citation needed]} This can be useful in locations with poor cell coverage where some other form of internet access is available,^[2] especially at the home or office. The system offers seamless handoff, so the user can move from cell to Wi-Fi and back again with the same invisibility that the cell network offers when moving from tower to tower.^[3]

Since the GAN system works over the internet, a UMA-capable handset can connect to its service provider from any location with internet access. This is particularly useful for travellers, who can connect to their provider's GANC and make calls into their home service area from anywhere in the world.^{[citation needed]} This is subject to the quality of the internet connection, however, and may not work well over limited bandwidth or long-latency connection. To improve quality of service (QoS) in the home or office, some providers also supply a specially programmed wireless access point that prioritizes UMA packets.^[6] Another benefit of Wi-Fi calling is that mobile calls can be made through the internet using the same native calling client; it does not require third-party Voice over IP (VoIP) closed services like WhatsApp or Skype, relying instead on the mobile cellular operator.^[7]