Control plane robustness in software-defined optical networks under targeted fiber cuts

Abstract

The Software-Defined Optical Networking (SDON) paradigm enables programmable, adaptive and application-aware backbone networks. However, aside from the manifold advantages, the centralized Network Control and Management in SDONs also gives rise to a number of security concerns at different network layers. As communication between the control and the data plane devices in an SDON utilizes the common optical fiber infrastructure, it can be subject to various targeted attacks aimed at disabling the underlying optical network infrastructure and disrupting the services running in the network. In this work, we focus on the threats from targeted fiber cuts to the control plane (CP) robustness in an SDON under different link cut attack scenarios with diverse damaging potential, modeled through a newly defined link criticality measure based on the routing of control paths. To quantify the robustness of a particular CP realization, we propose a metric called Average Control Plane Connectivity (ACPC) and analyze the CP robustness for a varying number of controller instances in master/slave configuration. Simulation results indicate that CP enhancements in terms of controller addition do not necessarily yield linear improvements in CP robustness but require tailored CP design strategies.