Voice over Wi-Fi (VoWiFi) is a technology that enables voice communication using a wireless internet connection rather than the mobile operator’s radio access network. First deployed in 2014, it’s particularly useful in areas with weak cellular coverage.

The ePDG is a network element designed for secure access and interworking between 3GPP networks (LTE/5G core) and non-3GPP networks (Wi-Fi). It acts as a security gateway, creating a secure connection from untrusted networks to the mobile core network.

For decades, voice has been at the heart of mobile communication, but the way it is delivered has changed significantly. From the earlier infrastructure-heavy systems to today's flexible, cloud-native architectures, voice technology has evolved to meet the growing demands of users. These include enhanced security features, seamless integration with data services, and the ability to support emerging use cases like IoT and AR/VR.