Abstract: With regard to the flow regulation of the best-effort traffic, i. e., the controllable traffic in high-speed computer communication networks, the paper proposes a novel control theoretic approach that designs a proportional-plus-derivative (PD) controller for congestion controlling. Based on the traffic model of a single node and on the system stability criterion, it is shown that the PD controller can regulate the source rate on the basis of the knowledge of buffer occupancy of the destination node in such a manner that the congestion-controlled network is asymptotically stable without oscillation in terms of the buffer occupancy of the destination node. Simulations show good performance of such controlled networks.