A Novel Fault Tolerance Mechanism for Software Defined Networking
Wael Hosny Fouad Aly · 2017
Software Defined Networking (SDN) is a new network design paradigm. SDNs depend on decoupling thecontrol plane from the forwarding plane atthe network switches. SDNs use logically centralized controllers that are responsible for directing the forwarding decisions to the connected switches. In this paper, we design a new model to provide fault tolerance using feedback control to SDNs based on load balancing schemes. The model is called load balancing to support fault tolerance using feedback control for SDNs (LBFTFB). LBFTFB improves the resistance to cascaded failures. Cascading failures cause an enormous increase in the load of the surrounding controllers as a subsequence of the failure of a certain controller. On SDN controller failures, the LBFTFB distributes the load on the failed controller among thesurrounding controllers based on a defined feedback control policy. The LBFTFB model reduces the cascading failure problem when compared to HyperFlow model which is considered as a reference model. The HyperFlow model is a distributed control plane for OpenFlow. HyperFlow model suffers from a dramatic increase in the load of the surrounding controllers as a consequence of the failure of a certain controller. This is an ongoing research. Tentative emulation results are promising and show that the LBFTFB model outperforms the reference model for cascading failures by 14% in terms of packet loss and 17% in terms of packet delays