Is it possible to wire a VoIP adapter to all the landlines in the house?

Question by I Like Men: Is it possible to wire a VoIP adapter to all the landlines in the house?
If I disconnect the wires that lead into the house from the POTS terminal outside, they will have no input. Then can I connect the output jack on the back of my VoIP router to any landline jack in my house to have VoIP to every landline jack?

Best answer:

Answer by Mr. VoIP
Yes, you can do that if your Internet is provided over cable TV line.
Obviously, you could not do that if you have DSL Internet because the DSL Internet comes in on the external telephone line.

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