Congestion control in software defined network

In recent time, the Software defined networking has become quite popular. OpenFlow protocol separates the network control from forwarding devices so it offers flexible and expansible functionality for networks. A large number of modules or applications has been developed for the SDN controller to fully utilize the flexibility and scalability of Software defined networking over traditional networking. Load balancing is one of the applications that is implemented in SDN. To balance the load on any node system needs to be sure that the destination node should be trusted. In case of load balancing, a node can also be labeled as trusted or not trusted when certifying migration request [24] [28]. This type of implementation can be implemented by SDN properties. As the applications increases day by day, communication between controller and the switches are also getting increased. Number of packets transmitting between the controller and switches increases as the number of applications are increased in the controller. In congestion control module the controller has to update itself very frequently by sending and receiving query response packets to get updated about the congestion state of switches. In this paper a congestion detection module has been modeled so that packet transmission between controller and switch can be reduce. This proposed method is executed on mininet and floodlight controller and analyze how to reduce those packets and provide the bandwidth of link between controller and switch to other applications. Results show that bandwidth utilize by the congestion control module is getting low.