Towards distributed hierarchical SDN control plane

This paper presents a concept for hierarchical distributed control of SDN networks. The proposed architecture is based on a heterogeneous control plane with a hierarchical structure that offers a general framework for building non-classical SDN deployments. This control plane organizes a group of controllers nodes, into a hierarchy, with each tier containing one or more interconnected controllers. The hierarchical approach is intended to improve scalability and increase service flexibility by distributing functionality between multiple controllers. A proof-of-concept implementation using the Floodlight SDN controller platform is described, and performance results demonstrating basic feasibility are given.