Designing Operational WDM Networks

Network design tools are routinely used in practice to design optical mesh networks that can support a given set of traffic demands at the least cost. These tools typically end up routing the given set of demands and assigning necessary equipment. The criteria used in routing demands during design and the order in which the demands are considered are often different from those encountered while provisioning the demands in the operational network. As a result, the routes computed may be different during design and provisioning, leading to over- or under- utilization of portions of the network and failure to route demands, which is catastrophic. In this paper, we propose a general iterative technique for solving this problem for any combination of design and provisioning algorithms. Depending on the correlation between the two algorithms, the resulting design can be more expensive than the cost-optimal design, but is guaranteed to handle the demands in the operational network. We provide experimental results to show the effectiveness of this technique for different combinations of routing criteria.