QoS functionality in software defined network

Quality of Service (QoS) in networking is a way of managing the network resources effectively. QoS has been widely used in traditional network and can also be implemented in Software Defined Network (SDN). Software Defined Network is a new network paradigm that decouples the control plane from the data plane in the network and thus create a network that is scalable, dynamic and easily manageable. QoS in SDN can be used to control the network bandwidth, latency and throughput. This paper presents the QoS functionality in SDN and uses OpenFlow protocol, OpenvSwitch and QoS application built on top Ryu controller. It also shows the use of tools such as iperf in testing the throughput and sflow in visualizing and monitoring the network at large.