Proactive failure recovery in OpenFlow based Software Defined Networks

Software Defined Networking (SDN) is a network architecture that decouples the control and data planes. SDN enables network control to become directly programmable and the underlying infrastructure to be abstracted from the network services. The foundation for open standards based software defined networking is the OpenFlow protocol. The OpenFlow architecture which is originally designed for Local Area Networks (LANs), doesn´t include effective mechanisms for fast resiliency. But metro, carrier grade Ethernet networks and industrial area networks have to guarantee fast resiliency upon network failure. This paper experiments the link protection scheme that aims to enhance the OpenFlow architecture by adding fast recovery mechanisms in the switch and the controller. This is achieved by enabling the controller to add backup paths proactively along with the working paths and enabling the switches to perform the recovery actions locally. As this avoids controller intervention during recovery, the recovery time solely depends upon the failure detection time of the switch. As this will be less compared to the switch-controller round trip time, this gives better results. The performance of the system is evaluated by finding the packet loss and switch over time and comparing it with the current OpenFlow implementations. The system performs reasonably better than the existing systems in terms of switch over time. However the number of backup path entries increase relatively.