Congestion control for high speed packet switched networks

The authors suggest and investigate a general input congestion control scheme that takes into account a broad spectrum of network issues. As a preventive congestion control strategy, a leaky-bucket-type scheme operating on a session basis that limits the session´s average rate and the burstiness is proposed. This restrictive control is combined with an optimistic bandwidth usage scheme which works by marking packets into two different colors, green and red. The packets are marked so that the average green packet rate entering the network is at the reserved average rate. The average red packet rate represents traffic in excess of this guaranteed average rate and is sent to further utilize unused bandwidth in the network. Both types of packets are further filtered by a spacer which limits the peak rate at which the packets enter the network. The marked packets are then sent into the network, where they are treated according to their color, using at each intermediate node a simple threshold policy