FIG. 2 shows the wiring configuration of a prior-art telephone system including a network 20 for a residence or other building, wired with a telephone line 5, which has a single wire pair that connects to a junction-box 34, which in turn connects to a Public Switched Telephone Network (PSTN) 41 via a cable 33 (local loop'), terminating in a public switch 32, which establishes and enables telephony