At some point, every thing's going through one or two pipes.
If you've digital phone service (which most everyone does these days) it's a protocol like VOIP, being that it's sent in a signal of ones and zeroes.
The differences are the carrier (cell phone, etc) and the technology it uses to encode/decode.
It's amazing, though, that you can virtually get IP/TCP to do anything. Gooo DARPA!