Broadband multi-channel switch with multicasting capability

Abstract

A multi-channel, multicasting switch for an ATM network utilizes a particular nonblocking condition of the Flip Network, which is exploited to realize a multi-channel switching architecture that supports an arbitrary number of channel groups. Using a single Flip Network recursively, the resulting architecture becomes efficient in the sense that the crosspoint complexity is O(N log.sub.2 N) for N inputs. The number of times the Flip Network is used recursively is a function of the number of channel groups only. The architecture is internally nonblocking and bufferless. Distinguishing features are the abilities to provide multicasting, super-rate switching (i.e., rates that exceed the capacity of a single channel are accommodated), multi-rate switching (i.e., bit pipes of different rates are supported simultaneously), multiple performance requirements (i.e., services with different performance requirements are treated accordingly), and fairness (i.e., cells originating from different input channels and/or destined for different output channels are treated fairly). In multi-channel switching, cells belonging to a single session can traverse over multiple channels and the architecture maintains cells in order by assigning a specific Gray code to each data cell in each group.