PNNI and the optimal design of high-speed ATM networks

In addition to being well-dimensioned and cost-effective, a high-speed ATM network must pass some performance and robustness tests. We propose an approach to ATM network topology design that is driven by the performance of its routing protocol, PNNI. Towards this end, we define performance indicators based on the time and traffic required for the protocol to first enter and subsequently return to the metastable state of global synchrony, in which switch views are in concordance with physical reality. We argue that the benefits of high call admission rate and low setup latency are guaranteed by our indicators. We use the PNNI Routing and Simulation Toolkit (PRouST), to conduct simulations of PNNI networks, with the aim of discovering how topological characteristics such as the diameter, representation size, and geodesic structure of a network affect its performance.