ROADM Configuration, Management and Cost Analysis in the Future Era of SDM Networking

As the demand for higher transmission capacities is increasing, optical networks will soon exceed the maximum achievable capacity leading to a capacity crunch. Space Division Multiplexing (SDM) aims to face this problem by using multiple spatial channels in Multi-Core Fibers (MCFs) and/or Multi-Mode Fibers (MMFs). SDM promises to increase the total transmission capacity and effectively reduce transmission costs. So, integrated scalable SDM components that can reduce costs by utilizing less hardware should be deployed. SDM efficiency can be enhanced by Jointly-Switching wavelength channels across all spatial channels, using an adapted Wavelength Selective Switch (WSS). In this paper we derive a cost analysis of various SDM network topologies. We consider the number of spatially dimensions, the R-degree of Colorless Directionless Contentionless Reconfigurable Optical Add-Drop Multiplexers (CDC-ROADMs), the number of spatially integrated transceivers and compute the optimal number of required WSSs. Our cost analysis shows that we can reduce the number of SDM components used, leading to an overall cost reduction of 33% and 58% for an 8-degree and 16-degree network node respectively. As future ROADMs will be available as black boxes, we propose the DCMP, a new Protocol for Dynamic Configuration and Management of SDM backbone ROADM nodes. Finally we study on a topology for a future SDM backbone network of Greece, and perform a detailed cost analysis resulting in a max cost reduction of 13%.