关键词: 软件定义网络（SDN）, 控制域, 负载均衡, 谱聚类算法

Abstract: By dividing the WAN (wide area network) into several SDN (software defined networking) control do-mains with smaller scale and balanced number of nodes, the service capability of the controller can be improved. However, there are still many challenges in determining of SDN control domains optimal number and partitioning of SDN control domains according to the SDN network topology. In this paper, a mechanism of determination and partition of SDN control domains is proposed. It uses the spectral clustering algorithm to solve the problem of determination and partition of SDN control domains with the target of balancing the controller load. Firstly, SDN control domains determination mechanism is designed based on eigengap spectral clustering algorithm to determine the optimal number of control domains. Then, SDN control domains partition mechanism based on normalized Laplacian matrix eigenvector is designed to make the number of switch nodes in each control domain relatively balanced. Finally, the simulation results show that the mechanism of determination and partition of SDN control domains proposed in this paper can determine the optimal number of control domains, and the relative balance of the number of switch nodes in each control domain can be achieved by partitioning SDN control domains.

Key words: software defined networking (SDN), control domains, load balancing, spectral clustering algorithm