AdaFlow: Adaptive Control to Improve Availability of OpenFlow Forwarding for Burst Quantity of Flows

The Software-Defined Networking (SDN) separates the control plane from the data plane to increase the flexibility. In the data plane, the unavailability of data forwarding is a common problem preventing a switch from configuring a new arrival flow into its flow table. When the burst flows arrived at the switch, the flow table can be consumed, causing the unavailability occurred. However, the problem is more complicated than in Internet due to the limited channel bandwidth for detecting the table usage. Hence, we propose a transparent core layer in the controller. The mechanism of the layer improves the availability in such way, configuring switches adapting to arrival patterns of flows to prevent the resource of switch exceeding its limit. This paper introduces the design and mechanisms of the layer as well as their algorithms. We further use a real flow trace from a Internet core router to evaluate the performance of layer. By emulating on on miniNet-HiFi, the results demonstrate that the layer can smooth the burst flows without making the flow table exceeding its size, without the layer, the switch lost 8% ingress flows. Meanwhile, the control throughput is lowered by 25.8% than before.