Near-Optimal Slot Sizes for the Single Mode Flexible-Grid Optical Networks

Flexible-grid Optical Networks provide efficient spectrum utilization by employing the mechanism to provide flexibility in the size of the optical channels (spectrum slots). One of the research problems in Flexible-grid Optical Networks is Routing and Spectrum Assignment (RSA), where such channels are allocated to demands. For such networks, the spectrum slot width size specified by the ITU-T G.694.1 is 12.5 GHz. However, one should question if it is the optimal grid size for RSA. In this paper, we determine suitable grid sizes with the help of connection blocking probability, bandwidth blocking probability, and spectrum efficiency as the performance parameters under different demand bandwidth distributions.