NFV recovery strategies for critical services after massive failures in optical networks

Today, more critical services than ever rely on the communication infrastructure of 5G and beyond, demanding resilient recovery strategies when disasters occur. The inherent uncertainty of disasters makes post-disaster recovery a complex challenge. Today’s solutions focus on external infrastructure, such as alternative power supply or ad-hoc UAVs, to restore communication. However, the programmable nature introduced in 5G also allows us to migrate (relocate) Virtual Network Functions (VNFs) to restore communication more efficiently. In this paper, we develop an experimental framework to evaluate the performance of recovery strategies utilizing VNF migration in an optical network. We demonstrate that selecting the appropriate post-disaster recovery strategy can significantly accelerate the restoration of critical services by several hours in some disaster scenarios. Furthermore, we create ClusPRi, a modification of the virtual resource allocation algorithm ClusPR. ClusPRi prioritizes critical traffic when allocating resources in a post-disaster scenario. We show that adding routing priority to the resource allocation algorithm further accelerates the restoration of critical communication in a disaster scenario.