Automated Fiber Type Identification in SDN-Enabled Optical Networks

Abstract

Network design margins are introduced by quality of transmission estimator inaccuracies. Some of those inaccuracies are due to uncertainty on the fiber type deployed in optical networks, and on the value of the chromatic dispersion of deployed fibers. We propose, in this paper, a method to identify all unknown fiber types (and estimate chromatic dispersion) in an optical network to reduce said uncertainties. We monitor, collect, centralize, and correlate chromatic dispersion values accumulated over each established light path, already measured by coherent receivers to autonomously identify fiber types without traffic interruption. Thanks to this method, we can identify the fiber type of all the 41-unknown links for a 28-node network built with four different fiber types and only 100 light paths. Our method is also capable of distinguishing two fiber types that only differ by their dispersion slope. We have also deployed and demonstrated this fiber type identification method at the ECOC 2018 demo session with real-time communication with our Lab from the demo floor. The SDN-enabled optical network is based on ONOS controller that periodically provides real-time chromatic dispersion values of active light paths needed for the autonomous fiber type identification.