Managing topology growth in ROADM networks [invited]

Deployment of a new technology across a large network can take years, usually with a strong economic imperative to load traffic onto the new layer as quickly as possible. Routing such traffic through the early-stage network can result in nonoptimized usage of resources in the fully built network, impacting the network's cost-effectiveness in ways not directly quantified by conventional design studies. Using network simulations of quasi-static traffic, we show that the order in which links are built affects the efficiency of the final network. If the optical layer can be hitlessly reconfigured, significant benefit is achieved by network re-optimization as the technology's footprint grows over time.