FlowBroker: A Software-Defined Network Controller Architecture for Multi-Domain Brokering and Reputation

Software defined networking (SDN) provides great flexibility by decoupling the control and the data planes, allowing for the implementation of new and innovative network control plane experiments. Presently, the reference implementation for SDN architecture is reliant upon a single controller to push flow rules to all SDN-enabled switches in the network, creating a performance bottleneck and single-point of failure in large networks. To provide a scalable yet efficient solution to distributed SDN network management, we propose FlowBroker, a hierarchical brokering agent layer which manages and coordinates among distributed SDN controllers, where each controller is charged with the flow-rule maintenance of the switches in its managed domain. This paper proposes the FlowBroker architecture as a collaborative multi-domain approach to load balancing and network performance enhancement in software-defined networks. Moreover, we introduce distributed machine learning agents to allow controllers to evaluate which brokers are more advantageous than others, from a performance-based reputation perspective. Simulation results show that the FlowBroker architecture, with broker-based collaborative load-balancing and controller-based distributed reputation, can significantly increase the network performance of a multi-domain software-defined network. FlowBroker yields significant reductions in traffic loss, end-to-end delay and maximum link utilization when cooperative brokering and reputation are utilized.