Destination routing

In the context of Telephone Switching System for circuit based calls, the destination stations are identified by a station address or more commonly, a destination number.

In the network there are various classes of switching systems.

An end office switch connects directly to the stations. It knows which circuit to activate (ring) when given a destination number.

Other switches in the network are for transport only. These are sometimes called tandem switches. In this case, the goal of destination routing would be to select an outbound span for a particular destination number.

The whole point of this is to get a continuous signal path from the starting location of the caller to the ending location of the called party.