SDN-Based IP and Layer 2 Services with an Open Networking Operating System in the GÉANT Service Provider Network

The migration of service providers' wide area networks toward SDN is a challenging task. In this article, we consider the critical requirements of GÉANT, the 500 Gb/s pan-European provider interconnecting 38 national research and educational networks, for a total of 50 million users. A long-term evolution path toward the softwarization of GÉANT is discussed, consisting of four steps to be realized...