The GTD-5 EAX is the Class 5 telephone switch developed by GTE

GTE

GTE Corporation, formerly General Telephone & Electronics Corporation was the largest independent telephone company in the United States during the days of the Bell System....

 Automatic Electric Laboratories. This digital

Digital

A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...

 central office telephone circuit switching

Circuit switching

Circuit switching is a methodology of implementing a telecommunications network in which two network nodes establish a dedicated communications channel through the network before the nodes may communicate. The circuit guarantees the full bandwidth of the channel and remains connected for the...

 system is used in the former GTE service areas and by many smaller telecommunication

Telecommunication

Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

s service provider

Service provider

A service provider is an entity that provides services to other entities. Usually, this refers to a business that provides subscription or web service to other businesses or individuals. Examples of these services include Internet access, Mobile phone operators, and web application hosting...

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The GTD-5 EAX first appeared in Banning, California on June 26, 1982, slowly replacing the electromechanical systems still in use in the independent switch market at that time.