Telephone switch

A telephone switch is a device for routing calls from one telephone to another. Usually a complex machine (or series of them) in a central exchange. They work by connecting two or more circuits together, each circuit being connected to a subscriber telephone, according to a dialed telephone number.

Telephone switches are usually owned and operated by a [telephone service provider]? and located in their premises, but sometimes individual businesses or private commercial buildings will house their own switch (which may well be owned and operated by a telephone service provider still).

Switches are used in both local central offices and in long distance centers.