What's the difference between CSFB & VoLGA

CSFB (Circuit-Switched FallBack) and VoLGA (Voice over LTE via Generic Access) are two different technologies used by mobile network operators for providing voice services over LTE (Long-Term Evolution) networks in situations where there is no LTE coverage available.

1. CSFB: CSFB is a technology that enables mobile devices to fall back to 2G/3G networks for voice calls when LTE coverage is not available. With CSFB, when a user initiates a voice call, the mobile device switches to the 2G/3G network to complete the call. When the call is completed, the mobile device switches back to the LTE network for data services. CSFB is widely used by mobile network operators to provide voice services over LTE networks.

2. VoLGA: VoLGA is a technology that enables mobile devices to use the existing 2G/3G network infrastructure for voice calls when LTE coverage is not available. With VoLGA, voice calls are transmitted over the 2G/3G network and then handed over to the LTE network when data services are required. VoLGA is designed to allow mobile network operators to offer voice services over LTE networks without having to upgrade their existing network infrastructure. However, VoLGA has not been widely adopted by mobile network operators.

In summary, CSFB and VoLGA are two different technologies used by mobile network operators for providing voice services over LTE networks in situations where there is no LTE coverage available. CSFB enables mobile devices to fall back to 2G/3G networks for voice calls, while VoLGA enables mobile devices to use the existing 2G/3G network infrastructure for voice calls. CSFB is widely used by mobile network operators, while VoLGA has not been widely adopted.