Evaluation of Lightpath Deployment Strategies in Flexible-Grid Optical Networks

With the recent advances in elastic optical networks, a significant increase in throughput is promised with the use of bandwidth variable transponders. These transponders support different lightpath configurations, in terms of data rate, modulation format, and bandwidth. Considering the ever-increasing traffic in the core optical networks, routing, configuration, and spectrum assignment (RCSA) algorithms are crucial to increase the network throughput over the planning periods. To do this, lightpaths should be configured with enough data rate, while guaranteeing the signal quality at the receiver. In this work, we present a detailed evaluation of different lightpath deployment strategies in the context of multi-period elastic optical network planning. We show that in our RCSA algorithm, a multi-objective optimization can cope with the increasing traffic by deploying up to 31% fewer lightpaths while reducing the over-provisioning by 9% compared with the greedy approaches. Further, our simulation results indicate that our proposed approach can lead up to 16% higher power-efficiency.