A distributed congestion-prevention scheme for ATM switching fabrics based on buffered delta networks

Existing packet combining schemes, implemented either by hardware or software, developed for hot-spot congestion-control in multiprocessors are not applicable for use in telecommunication systems. The authors propose a hot-spot prevention scheme which exploits the structural characteristics of buffered delta networks to regulate the traffic. This scheme prevents the tree saturation by controlling the flow of the packets into the network and ensures that the hot-spot traffic can be supported with little degradation to the throughput of the uniform traffic, even when more than one hot-spot exists. The scheme retains all the desirable properties, including packet order preserving, of buffered delta networks, and is shown by simulations to be highly effective under either light or heavy hot-spot traffic. Since no a priori knowledge of the traffic patterns is required, the proposed scheme can be applied equally well to buffered delta networks in multiprocessors and telecommunication systems