The invention is a tandem system (300) for providing a tandem connection for circuit-based traffic. This tandem system comprises an ATM cross-connect (370), ATM interworking multiplexers (360, 364), and a signaling processor (350). The multiplexer converts the traffic received by the tandem system into ATM where it is routed through the cross-connect and re-converted back into the circuit-based format at an ATM interworking multiplexer. The signaling processor controls the virtual connections and outgoing circuit-based connections used by the multiplexers.