A Box-Covering-Based Routing Algorithm for Large-Scale SDNs

A routing algorithm is the pivotal and core issue in network communication. Traditional networks often use distributed routing algorithms that lead to difficulties in controlling network routes and accessing information concerning global topology. A software-defined network (SDN) is a new network framework that separates the network control plane from the forwarding/data plane. SDNs can access global topology through SDN controllers and make forwarding decisions based on flow tables. In this paper, we propose a box-covering-based routing (BCR) algorithm using a renormalization method that is applied to research the fractal dimensions of large-scale networks. We divide the entire SDN network into some subnets using a box-covering method, find the shortest path in every subnet and between subnets, and embed the proposed BCR algorithm code inside the SDN controller. We then design a testbed based on the Ryu controller and the Mininet platform for this algorithm. The results show that the proposed BCR algorithm has good low-latency performance and is suitable for a large-scale SDN.