Performance of feedback flow control mechanisms in large high-speed networks

Data traffic appears today as a critical issue for the design of high-speed networks. Since data traffic cannot in general be characterized in a simple manner, effective preventive congestion control mechanisms are difficult to realize. Reactive mechanisms can be employed instead, but such mechanisms are not easily adapted to the case of non-negligible propagation delays. We proposed a feedback control mechanism that explicitly takes into account the network propagation delay. In this paper, we study the behavior of an interconnection system under the proposed control and we develop an exact analytical solution for the evolution equation of the destination unit. This result allows us to determine the value of the optimal command and to infer the maximum buffer requirements. Simulation provides a good confirmation of the analytical results. We conclude the paper with a discussion of implementation and interoperation issues.