Mitigating Elephant Flows in SDN-Based IXP Networks

Internet Exchange Points (IXPs) play a key role in the Internet architecture, enabling cost-effective connections among multiple autonomous systems (ASes). The management of IXP networks includes the activity of taking care of elephant flows; they represent a small number of the total flows of an IXP, but have high impact on the overall network traffic. Managing elephant flows involves adequate identification and eventually rerouting of such flows to more appropriate locations, to minimize the possible negative impact on the other (mice) flows. Elephant flow management becomes even more important in SDN-based IXPs that require controllers to have a consistent view of the underlying network to allow fine-grained adjustment. In this paper, we propose, develop, and evaluate a recommendation system to suggest alternative configurations to previously identified elephant flows in an SDN-based IXP network. In our solution, the IXP operator can define templates that ultimately define how elephant flows can be rerouted to achieve a specific objective. We demonstrate that our system can help IXP operators to mitigate the impact of elephant flows on the IXP network.