A telecommunication circuit is a path in a telecommunications network used to transmit information. Circuits have evolved over time from generally being built on physical connections between individual hardware cables, as in an analog phone switch, to virtual circuits established over

packet switching In telecommunications, packet switching is a method of grouping Data (computing), data into ''network packet, packets'' that are transmitted over a digital Telecommunications network, network. Packets are made of a header (computing), header and ...

networks.

Definitions

A telecommunication circuit may be defined as follows: * The complete path between two terminals over which one-way or two-way communications may be provided. * An electronic path between two or more points, capable of providing a single or multiple communication channels. * An electronic closed-loop path among two or more points used for signal transfer. In operational terms, a telecommunication circuit may be capable of transmitting information in only one direction (''simplex'' circuit), or it may be bi-directional (''duplex'' circuit). 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 signal An analog signal or analogue signal (see spelling differences) is any continuous signal representing some other quantity, i.e., ''analogous'' to another quantity. For example, in an analog audio signal, the instantaneous signal voltage vari ...

Radio station Radio broadcasting is transmission of audio (sound), sometimes with related metadata, by radio waves to radio receivers belonging to a public audience. In terrestrial radio broadcasting the radio waves are broadcast by a land-based radi ...

s used them as

studio transmitter link A studio transmitter link (or STL) sends a radio station's or television station's audio and video from the broadcast studio or origination facility to a radio transmitter, television transmitter or uplink facility in another location. This is ac ...

s (STLs) or as remote pickup unit (RPU) for

sound reproduction Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recordin ...

, 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 (POTS) and

ISDN Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the digitalised circuits of the public switched telephone network. Wor ...

telephone A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into el ...

lines are switched circuits. On certain

telecommunication circuits, a virtual circuit may be created, while sharing the physical circuit.

Definitions

Applications

See also

References

Further reading