Resource Allocation in WDM vs. Flex-Grid Networks: Use Case in CEDIA Optical Backbone Network

In this paper, we evaluate in a network planning scenario the performance of typical Wavelength Division Multiplexing (WDM) networks versus networks based on flexible spectrum grid (i.e., Flex-Grid networks). To this end, we propose several lightweight heuristics with adaptive routing strategies and a Simulated Annealing (SA)-based metaheuristic in order to minimize the spectrum occupation. Moreover, we use the CEDIA backbone network under realistic traffic scenarios. The results obtained with the most promising heuristic disclose that, for foreseeable traffic conditions, spectrum savings up to 42% can be obtained if elastic spectrum allocation is considered compared to rigid spectrum allocation. Furthermore, according to the results the current spectral resources of CEDIA network will be exhausted by mid-2023 using spectrum allocation based on Mixed-Line-Rate (MLR) WDM, while this estimation will extend until near 2025 if allocation based on Flex-Grid is considered.