Network Design: Algorithms and Examples

This article addresses the issues in data network design. We discuss graph models for network, issues in topology design and optimization, link and node capacity assignment, path search Algorithms, and network flow assignments. The network can support point-to-point packet-switched, connection-oriented circuit-switched, virtual circuit-switched connections. We also address performance issues such as blocking probability, throughput, and delay and how to account for them in the design of a network. The issue of fault tolerance in network design is also examined. The design is explained using a context of wavelength division multiplexed (WDM) fiber-optic network. Although Estrin-first proposed the idea of a reconfigurable system in the form of a fixed plus variable structure computer in 1960 (1) it has only been in recent years that reconfigurable fabrics have reached sufficient density to make them a compelling implementation platform for high Performance applications and embedded systems. In this article, intended for the non-specialist, we describe some of the basic concepts, tools and architectures associated with reconfigurable computing. Keywords: network optimization; graph algorithm; topological design; cutset saturation method; link capacity assignment; heuristic methods for capacity assignment; network flow assignment; max-flow min-cut theorem; flow deviation method; routing algorithms; wavelength division multiplexed (wdm) networks; fault tolerance in network design; optical fiber networks; light trail network