Dynamic crosstalk-aware lightpath provisioning in spectrally-spatially flexible optical networks

We focus on the problem of crosstalk-aware lightpath provisioning in a dynamic, spectrally and spatially flexible optical network, in which spectral super-channels are carried over multi-core fibers with distance-adaptive transmission. The problem involves establishing a lightpath for a connection such that the inter-core crosstalk (XT) between the new lightpath and any exiting lightpaths does not cause the quality of transmission of any of these light-paths to be below an acceptable level. To this end, we analyze and compare two broad classes of schemes that aim to ensure acceptable XT levels in the network. The first is based on static/worst-case XT, whereas the second uses dynamic/ precise XT estimation. These methods are implemented in a dynamic XT-aware routing, spatial mode, and spectrum allocation algorithm that solves the lightpath-provisioning problem efficiently with the goal of minimizing bandwidth blocking. Extensive simulation experiments performed in realistic network scenarios indicate that the utilized XT estimation methodology has a significant impact on network performance, with the precise XT approach favored over the worst-case XT strategy.