Pstn

PSTN stands for Public Switched Telephone Network. It is the traditional circuit-switched network used for voice communication over landlines. The PSTN includes all the world's circuit-switched telephone networks that have been used for voice communication since the late 19th century, connecting homes and businesses to each other via a global network of switches, cables, and other infrastructure. It operates using analog technology for much of its history, though it has increasingly been converted to digital systems in recent decades.