Next-generation router model for unicast and multicast communication simulations

Multistage switching fabrics are the most efficient method for scaling packet switches to very large numbers of ports. This article concerns the Clos/Benes network, which is the lowest-cost switching fabric known to yield operation free of internal blocking. To achieve this, we had to successfully combine switch fabric architecture, multipath routing, and internal buffering. We present an architecture for which we have examined the necessary conditions for freedom from blocking for a multipath cell distribution algorithm. Using NS-2 simulator, we verify operation free of internal blocking for unicast and evaluate blocking and various cell distribution methods for multicast traffic.