Abstract
This paper focuses on challenges and research issues of decision maker for solving complex problems having multiple subjective and conflicting choices for SDN Controller, which select multiple properties of the controller for better efficiency of network equipment eventually increasing network throughput and having less delays and cost saving. Making the network migration toward SDN in seamless and giving better results for the users. Throughput for the network can be increased by having centralized controller and no processing at network elements like switches and better traffic management thereby decreasing the latency as less as possible. SDN will helps to improve centralized visibility as all the underlying open flow switches are connected to controller, all switches can be configured from SDN controller without accessing individual switches. This research will help how we select the best possible SDN controller which in result will help reduce the complexity of a network, price of implementation and maintenance of the network, empower scalability, less hardware and software requirements, less technical resources requirements, centralized visibility, hassle free traffic engineering, high availability of network.