A modular, substantially infinitely-growable, multi-node switching system operates under distributed control to serve integrated circuit-switched and packet-switched traffic at the data rates appropriate for each type of traffic. The system comprises a plurality of interconnected identical switching units that form at least one communication switching node. A communication switching node is a modular building block of the system; a switching unit is a modular building block of a switching node, and hence also of the system. A plurality of communication endpoint nodes--illustratively PBXs--is connected to the one or more switching nodes for communicating with each other through the switching nodes. A plurality of communication links each connect a different one of the system's switching units to either (a) one of the communication endpoint nodes or (b) a unit of another switching node. All of the links have the same communication format. Each switching node includes a plurality of different ones of the identical switching units, and a communication medium that interconnects all of the units of the switching node to allow each unit of a node to broadcast all communications received from a connected link to all of the units of the node.