So the way calls can come in and out are either through the internet or Business Telephone systems. You have one of these providers that provides you a Voice over IP trunk. and so what happens is when you go to call out, your little phone connects to the Voice over IP server. The Voice over IP server then connects to those Voice over IP trunks.
Or on your Voice over IP server, you can have connections to connect you to normal phone lines from the outside world. So I say here in Baltimore we use Verizon for our phone company. But whatever phone company you use, they have their little phone line or Business Telephone systems. And again if your Voice over IP server has the right plugs, you can plug one of these phone lines from your telephone company into the Voice over IP server.
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