The big PSTN switch-off is due in 2025 which means that the old copper PSTN phone ... telephone calls. Digital Voice (using VoIP technology – Voice over Internet Protocol) will replace it, and for ...

For five years AT&T had wanted to link the phone lines from one side of the country to the other. They finally found the device that could help them do it: Lee De Forest's "audions," the first ...

Telephone companies had replaced most of their long-distance trunks and switching equipment with digital technology. Once a home user’s phone line hit a central office, it was usually ...

(1) (Voice Over IP modem) A device that converts Internet-based voice service from the cable or telephone company to the user's telephones. Officially called an analog telephone adapter.