IP PBX is actually a class of office telephony systems that use the internet protocol for call handling and forwarding. In contrast to the old traditional phone system, this type of system uses costly hardware and relies on the utilization of dedicated phone lines; instead, IP PBX solutions route voice over the internet, which actually makes it an economically viable alternative. https://medium.com/@shrutikamishra2/what-is-an-office-telephony-a-comprehensive-guide-e8e51b395b51