Implementation of Server Load Balancing in Software Defined Networking

Abstract

Network management is very painful and tedious process in large networks having hundreds of switches and routers. Software Defined Networking (SDN) is a new way for creating, designing and managing networks which aims to change this current undesirable situation. The main idea of SDN consists in logically centralizing network control in a SDN controller, which controls and monitors the behavior of the network. In this paper we developed an SDN application that performs server load balancing. The Main problem with traditional load balancer is that they use dedicated hardware. That hardware is very expensive and inflexible. Network Administrators cannot write their own algorithms since traditional load balancers are vendor locked. Therefore to solve these problems, we created SDN application which turned simple OpenFlow device into powerful load balancer. There are already certain existing load balancing algorithms in SDN but main problem with all these algorithms is that every request and return message has to pass through the load balancer. It introduces unnecessary latency. To solve these problems we implemented direct routing based load balancing algorithms. In Direct Routing, the load balancer is not involved in the return message from the web server to the client. It means server responds directly to client bypassing the load balancer thus improving performance.