Software-defined inter-domain switching

Software Defined Networking (SDN) technology has garnered much attention in the field of networking. Even though there have been several SDN based data centre (domain) implementations, there is a need to inter-connect multiple SDN domains. In this thesis we will focus on enabling inter-domain layer 2 switching. We propose an approach wherein a central controller is responsible for inter-domain switching while the domain controllers are responsible for intra-domain switching in their respective domains. To achieve this, the central controller initially communicates with the domain controllers to gather the overall topology of the network. From the overall topology, the central controller can derive the domain-level topology, compute the domain-level spanning tree and install the tree on the topology. In addition, the central controller also computes the inter-domain shortest path between any pair of domains. The shortest path information are then pushed to the domain controllers in order to setup the network-wide shortest path. We demonstrate the viability of the proposed approach by implementing it in OpenDayLight, a popular SDN platform. To further demonstrate the flexibility and openness of the approach, we have also successfully implemented a user case to achieve inter-domain load balancing.