Abstract: The system and method of the present invention provide a mechanism, for the purpose of efficiently interconnecting local area networks (LANs) across a frame relay network, by which LAN stations provide data flow control when the frame relay network becomes congested. The system of the invention comprises a Station Manager at the network end point internetworking unit (IWU) for managing the IWU, a LAN Manager for managing one or more LANs connected to the end point IWU, and Station Managers at each of the LAN stations managing the respective LAN station. In operation, the IWU receives from the frame relay network a congestion notification and the IWU Station Manager broadcasts this notification to its managed LAN station Station Managers. The LAN station Station Managers each examine the notification against its outstanding data to be transmitted and slows down data traffic that is destined for the congested portion of the frame relay network.