High Level Policies in SDN

Policies for network traffic handling define packet routes through networks, enforce required quality of service, and protect networks from security threats. When expressing a policy, one needs to characterise the traffic to which the policy applies by traffic identifiers. Low level traffic identifiers, such as IP addresses and port numbers, are available in each packet. Indeed, low level traffic identifiers are perfect for data plane routing and switching. However, high level traffic identifiers, such as user name and application name, are better for the readability and clarity of a policy. In this paper, we extend software defined networks with high level traffic identifiers. We propose to add additional interface to SDN controllers for collecting traffic meta data and high level traffic identifiers. The controller maintains a database that maps high level traffic identifiers to a set of flows defined by low level traffic identifiers. SDN applications can apply policies based on both high level and low level traffic identifiers. We leave the southbound protocols intact. This paper provides two examples of High Level SDN paradigms – Application-Aware Networks and Identity-Aware Networks. The first paradigm enables policies depending on application names and characteristics. The latter allows policies based on user names and their roles.