OpenROADM for Disaggregated Optical Networks: Challenges, Requirements and Evaluation

Control, management, and orchestration of disaggregated Optical Transport Networks (OTN) require consistent abstractions of the optical network elements (NEs). These abstractions represent the configuration and operation-related device parameters through standardized data models like OpenConfig or OpenROADM. The unified data model approach on the one hand avoids vendor lock-in and enables cost reductions and increased flexibility in OTN deployment, but induces increased complexity to support, configure, and provision end-to-end network services. Therefore, partial disaggregation has been proposed where the entire optical transport network is separated into two parts, namely the open Optical Terminal (OT) and the Optical Line System (OLS) which in turn may comprise multiple autonomous OLS domains. This paper focuses on the OpenROADM model and evaluates the challenges and requirements from both the data plane and control plane perspectives. The main novelty of our work lies in the evaluation of the OpenROADM capabilities compared to OpenConfig and vendor-specific models as well as of open-source SDN controllers that support OpenROADM.