Telecommunication circuit


A telecommunication circuit is an electrical path in telecommunication used to transmit information.

Definitions

A telecommunication circuit may be defined as follows:
In operational terms, a telecommunication circuit may be capable of transmitting information in only one direction, or it may be bi-directional. Bi-directional circuits may support half-duplex operation, when only one end of the channel transmits at any one time, or they may support full-duplex operation, when independent simultaneous transmission occurs in both directions.

Applications

Originally, telecommunication circuits transmitted analog information. Radio stations used them as studio transmitter links or as remote pickup unit for sound reproduction, sometimes as a backup to other means. Later lines were digital, used in pair-gain applications, such as carrier systems, or in enterprise data networks.
A leased line, private circuit, or dedicated circuit, is a circuit that is dedicated to only one use and is typically not switched at a central office. The opposite is a switched circuit, which can be connected to different paths in a switching center or telephone exchange. Plain old telephone service and ISDN telephone lines are switched circuits.
On certain types of telecommunication circuits, a virtual circuit may be created, while sharing the physical circuit.