Distributed SDN for Mission-Critical Networks

Mission-critical networks now interconnect data enters, enterprise, customer sites and mobile entities. They thus must be resilient, adaptable and easily extensible. The emergence of Software-Defined Networking (SDN) protocols, which enables to decouple the control plane from the data plane, opens up new ways to architect such networks. In this paper, we propose DISCO, an extensible Distributed SDN Control plane able to cope with the distributed and heterogeneous nature of modern mission-critical networks. DISCO controllers manage their own network domain and communicate with each others to provide end-to-end network services. This inter-controller communication is based on a lightweight and highly manageable pub-sub mechanism used by agents to self-adaptively share aggregated local and network-wide information. We implemented DISCO on top of Floodlight, an Open Flow controller, and the AMQP protocol. We demonstrated how DISCO's control plane dynamically adapts to heterogeneous network topologies while being resilient enough to survive to disruptions and attacks and providing classic functionalities such as end-point migration. The experimentation results we present are organized around two use cases: inter-domain connectivity disruption and migration of a virtual machine.