Public Switched Telephone Network (PSTN)

Definition of Public Switched Telephone Network (PSTN) in The Network Encyclopedia.

What is Public Switched Telephone Network (PSTN)?

Public Switched Telephone Network, also known as PSTN, is the public telephone network managed by the local telco and long-distance carriers. The Public Switched Telephone Network (PSTN) consists of a digital backbone of switched circuits together with the analog local loop wiring still found in many residences. The PSTN is also known as the Plain Old Telephone Service (POTS), although that term specifically relates to the older, nondigital portion of the PSTN.

Public Switched Telephone Network (PSTN)
Public Switched Telephone Network (PSTN)
(Graphic from

The PSTN provides the most popular basis for creating wide area networks (WANs) through both leased lines and dial-up lines between local and remote networks.

PSTN is often used in wide area networking because of its ubiquitous nature – local loop connections exist almost everywhere in the world.


Articles posted after being checked by editors.

Recent Content

link to Power-on Self Test (POST)

Power-on Self Test (POST)

Power-On Self Test is a special set of ROM routines that run whenever a PC is booted. The power-on self test (POST) is designed to test whether system components are functioning properly before attempting to boot the operating system, and checks such things as the RAM, keyboard, and disk drives.