While operating your Business Phone Systems the secretary will pick up the phone and say “Hello, how may I help you.” and you will be able to talk in.
Again, this intercom system will be an extension, say 805. So if you are sitting at a telephone and plug in the extension 805, when you start talking, that is going to go out over the intercom system in the warehouse or wherever. So, with PBXs, with telephone systems, you are dealing with more than telephones. You are dealing with intercom systems, callboxes, etc…
Now, how these telephones and the callboxes and all that communicate back with the PBX is something important to understand. You have your PBX right here, and you have your telephone. Now, in a normal, now we’re not talking about Voice Over IP, get all that crap out of your head, because we’re not talking about that right now. In normal telephone systems, you have two ways to transmit communication.
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