Traffic Load Balancing Using Software Defined Networking (SDN) Controller as Virtualized Network Function

Abstract

SDN and NFV are collaboratively recognized as the most promising bearing for flexible programmability of network control functions and protocols with dynamic usage of network resources. SDN provides the abstraction of network resources over well-defined APIs to achieve underlying topology-independent multiple tenant networks with required QoS and SLAs. NFV paradigm deploys network functions as software instances, namely, VNFs on commodity hardware using virtualization techniques. In this way, virtual IP functions, such as load balancing, routing, and forwarding or firewall, can operate as VNF in a cloud with a positive outcome in network performance. In this paper, we aimed to achieve traffic load balancing by using a virtual SDN (vSDN) controller as a VNF. With vSDN, when there is uneven and increased load, secondary vSDN controllers can be added to share this load. The need of secondary vSDN is determined and a copy vSDN with exactly the same configurations as original vSDN is created, which operates accurately and shares traffic load balancing tasks with an original vSDN controller. Both vSDN controllers are independently placed in the cloud with transparency assuring that every client in the network is familiar with the existence of the newly created secondary vSDN controller. We experimentally validated the load balancing in Fat-Tree topology using two vSDN controllers in a Mininet emulator. The results showed 50% improvement in average load, 41% improvement in average delay, and considerable improvements in terms of ping response, bandwidth utilization, and throughput of the system.