A generic framework to support application-level flow management in software-defined networks

Software-Defined Networking (SDN) provides a highly flexible flow management platform through a logically centralized controller that exposes network capabilities to the applications. However, most applications do not natively use SDN. An external entity is thus responsible for defining the corresponding flow management policies. Usually network operators prefer to control the flow management policies, rather than granting full control to the applications. Although IP addresses and port numbers can suffice to identify users and applications in ISP networks and determine the policies applicable to their flows, such an assumption does not hold strongly in cloud environments. IP addresses are allocated dynamically to the users, while port numbers can be freely chosen by users or cloud-based applications. These applications, like computing or storage framework, use diverse port numbers which amplifies this phenomenon. This paper introduces higher-level abstractions for defining user- and application-specific policies. These policies are then automatically mapped to OpenFlow rules by retrieving flow-based information of active users and applications in real-time. We implemented this framework and evaluated its practicality by measuring the underlying overhead.