Towards Regeneration in Flexible Optical Network Planning

In optical networks, the reach of the optical signal is controlled by the receiver’s capability to successfully receive the signal, degraded due to optical impairments and noise. This reach can be extended by using regeneration at intermediate nodes. Efficient placement and minimization of the number of regenerators is referred to as the regenerator placement problem. This paper proposes a method to solve the regenerator placement problem in a multiperiod planning scenario with the objective of maximizing throughput with minimum lightpaths. The paper addresses regenerator placement in two phases, a preselection of possible locations for regeneration based on OSNR constraints, and provisioning a combination of regenerated and non-regenerated lightpaths. The provisioning formulation focuses on minimizing the number of transceivers while maximizing the datarate. We demonstrate the advantage of our approach compared to state-of-the-art methods in terms of throughput, underprovisioning and number of transceivers on 3 different topologies. Our results show that the proposed solution is able to meet the dynamic traffic with lower underprovisioning.