A new local-toll telephone network configuration which, using aspects of data network configurations in a unique way, supports both voice and data telephone calls. Further, this invention may be used in conjunction with existing switching systems, so that there is a minimal of capital required to upgrade a local switching system for competitive access. An ATM switch is configured so that there are permit virtual circuits (PVCs) connecting switching offices connected to it. The synchronous data stream is connected to asynchronous and the circuit identifier code is included in the payload. Thus, the ATM switch is serving as a conduit for large amounts of data (including packetized voice) between local telephone switching systems while not having to take the time to set up each connection individually.