A growable packet (ATM) switch architecture: design principles and applications

The authors consider the generic problem of designing a large N×N(N>1000) high-performance, broadband packet (or asynchronous transfer mode) switch. They provide ways to construct arbitrarily large switches out of modest-size packet switches, without sacrificing overall delay/throughput performance. They propose and study a growable switch architecture based on three key principles: (a) a generalized knockout principle which exploits the statistical behavior of packet arrivals and thereby reduces the interconnect complexity; (b) output queuing, which yields the best possible delay/throughput performance; and (c) distributed intelligence in routing packets through the interconnect fabric. Other features include the guarantee of a first-in first-out packet sequence, broadcast and multicast capabilities, and compatibility with variable-length packets. In a broadband ISDN (integrated services digital network) example, the authors show a 2048×2048 switch configuration with building blocks of 42×16 packet switch modules and 128×128 interconnect modules