Digital Loop Carrier

What Does Digital Loop Carrier Mean?

A digital loop carrier (DLC) is a system that transmits digital multiplexed data signals by using existing cabling for distribution.


Techopedia Explains Digital Loop Carrier

The system starts transmission at the central office on a high speed digital line, where transmissions are routed to remote digital terminals. The signal is then converted to a form passed to low speed lines routed to end users telephones. Twenty-four analog voice calls are combined into single signals and transmitted over single copper T carrier systems. Installations using digital loop carriers connect analog phone lines of individual users into a single signal sent on single lines to the central office of a phone company. The combined signal is separated into original signals at the central office.

When transmissions are sent from end users, the process is reversed. The system collects transmissions and multiplexes them to be sent in aggregate to central offices of local loops.

A DLC carries traffic for regular phone lines and integrated services digital network (ISDN) services. It is used as an effective method for providing services to office buildings or complexes. It also is used to extend services to new areas outside current local loops. DLC can also set up telephone service in emergency situations. Customers can migrate from T1 or E1 lines to fiber optic lines when it is needed and available.


Related Terms

Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.