Tandem Switch

Tandem: In a telecommunications context, the term refers to switches, circuits, or other Network Elements (NEs) that serve to allow other NEs to work together. For example, tandem switches, or tandem offices, serve to interconnect other, lesser switches, (i.e. Central Offices [CO's] or lesser tandems). Tandem switches, in the purest sense of the term, serve no end users directly, as that is the responsibility of the COs. Rather, they strictly serve to interconnect the COs, which are at the lowest level of the switching hierarchy in the PSTN. Tandem tie trunks serve to interconnect tandem switches.


Tandem Switch: Tandem is a telephony term meaning to "connect in series." Thus a tandem switch connects one trunk to another. A tandem switch is an intermediate switch or connection between an originating telephone call location and the final destination of the call. The tandem point passes the call along. A PBX can often handle tandem calls from other/to other locations as well as process calls to, from and within its own location.



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