A new protocol layer is provided as part of a protocol stack associated with a packet-based multiaccess mobile communications system. The protocol layer is preferably located above a medium access control (MAC) protocol layer and a physical protocol layer of the system and below a transport/network protocol layer. Such a subnetwork protocol layer provides, inter alia, the communications system with various mobility management functions, for example, tracking mobile user stations throughout the system, mobile station access to the system, and connection/call continuity within the system. The subnetwork protocol layer of the invention also performs packet routing functions associated with the system. Routing can be accomplished in many ways, for example, via source routing, connectionless routing, or tunneling. Further, the new protocol layer of the invention is preferably located above a data link layer with respect to the protocol stack associated with communications between network nodes.