Hurricane Watch: An announcement that sustained winds of 64 knots (74 mph or 119 km/hr) or higher are possible within the specified area in association with a tropical, subtropical, or post-tropical cyclone.
PSTN Definition The public switched telephone network (PSTN) is the worldwide collection of interconnected public telephone networks that was designed primarily for voice traffic. The PSTN is a circuit-switched network. That is, a dedicated circuit (also referred to as a channel) is established for the duration of a transmission, such as a telephone call.
Circuit Switching. The PSTN is what is known as a circuit switching network. In other words, when a telephone call is made, an exclusive dedicated circuit is established and only released when the call ends.hares & Saves. Save. PSTN is an abbreviation for Public Switched Telephone Network and is used to describe a network of interlinked telephone systems---state-owned or commercial---and includes everything but private telephone systems that are managed by their own PBX (Private Branch eXchange).