With the growing interest in Software Defined Networking (SDN) and thanks to the programmability provided by SDN protocols like OpenFlow, network application developers have started implementing solutions to fit corporate needs, like firewalls, load balancers and security services. In this paper, we present a novel solution to answer those needs with usage control policies. We design a policy based management framework offering SDN network security policies. This approach is used to enforce performance requirements (e.g., to ensure a certain level of network connectivity). A top-down approach is proposed, in order to refine the policies into the appropriate network rules, via the OpenFlow protocol. Finally, we implement the solution with an availability service use case and we provide a set of experiments to evaluate its efficiency.