Progress Toward Optimal Nonblocking Multipoint Virtual Circuit Switching Networks

Over the last several years, a variety of multipoint virtual circuit switching systems have been proposed for use in Asynchronous Transfer Mode (ATM) networks. The inherent flexibility of ATM networking and the desire to apply this technology to a wide range of different applications makes it impractical to rely on statistical traffic models when engineering a system. This motivates a renewed interest in networks which are nonblocking with respect to requests to create or modify multipoint virtual circuits. While the various multipoint switching system architectures can all be configured to achieve nonblocking operation, for most, the cost of the nonblocking configuration quickly becomes prohibitive. We examine the complexity characteristics of a variety of multipoint switch architectures, taking into account the switching network, the memory required for routing multipoint virtual circuits and the effort required to create or modify a virtual circuit. In particular, we show that a ver..