Assessing the Scalability of Next-Generation Wavelength Switched Optical Networks

We are currently facing two major challenges for the development of future photonic networks: scalability and cost/energy efficiency. The process of evaluating the impact on the network of the expected increase of traffic demand is called scalability analysis. It is one of the most important tasks for a network designer, along with minimizing energy consumption and cost. In this paper, we propose a novel approach to assess wavelength switched optical network (WSON) scalability and efficiency. Our method takes into account the routing constraints of reconfigurable optical add/drop multiplexers (ROADMs), a variety of coherent transmission systems, different amplification schemes and types of fibre. We have assessed the network scalability and the roadmap for technological upgrades by running simulations of the recently deployed Telecom Italia´s WSON Kaleidon. We have used realistic traffic profiles and traffic growth-rate projections under a variety of case studies of practical interest. This study provides an innovative tool and insights to drive network designers´ decisions based on the impact of present and future photonic technologies.