This is a method of providing a phone service to people over the Internet. This type of service moves the traditional phone switch off site and allows more than one company to use a particular switch.
This is a way of communicating on the half-duplex communication line, includes receiving and transmitting devices (walkie-talkie) by the way of pressing the button for switching to the voice mode or transition to the listening mode. It works as a radio speaker; one can talk by pressing the button and can listen to a voice message by releasing the button.