Physical network design to facilitate capacity reallocation Original Research Article

Asynchronous transfer mode (ATM) is a multiplexing and switching technique that supports integrated services in high-speed networks. Flexibility is crucial in order to handle the dynamic resource requirements of multimedia traffic in these networks. ATM provides virtual paths (VPs) that can facilitate resource management. The physical topology of an ATM network should be designed to provide flexibility to the logical VP reconfiguration mechanism in order to adapt to changing traffic conditions. In this paper, we address the problem of physical topology design for ATM networks with a view to facilitating the logical reconfiguration phase. A basic physical topology design model is formulated as a nonlinear mixed integer programming problem and a graph-based heuristic algorithm is developed to solve the problem. Three models to support multiple traffic types are designed based on this model. Two parameters in this model control the spare capacity and the secondary route allocation. The static performance evaluation experiments indicate that the secondary route allocation parameter has more effect on the physical topology than the other and that the two parameters can be adjusted to achieve better performance with little increase in network cost. Simulation results show that the physical topology generated by the heuristic algorithm improves the dynamic capacity reallocation in the logical VP network.