What is FreeSWITCH? FreeSWITCH is free and open-source software that can be used to build and deploy private branch exchange (PBX) systems, IVR services, videoconferencing platforms, and other applications that require real-time communication. It is a powerful and flexible platform that can be used for a variety of purposes, including VoIP (Voice over IP) telephony, messaging, and presence. FreeSWITCH is written in C and C++ and has a modular architecture. It is made up of a number of independent modules that can be used to add new features or to customize the software. FreeSWITCH can support a large number