A novel multi-controller flow schedule scheme for Fat-tree architecture

OpenFlow is currently the most commonly deployed Software Defined Network (SDN) technology. Some deployments designed with multi-controller OpenFlow have better scalability than standard OpenFlow. However, these deployments are not optimized for the Data Center Network (DCN), the cross-controller communication and routing may be inefficient. In this paper, we present the communication mechanism design and implementation of optimized multi-controller OpenFlow for the Fat-tree through three aspects: partition scheme, routing algorithm and cross-controller communication. The result shows that our design performs well in terms of bandwidth and latency.