SDN中一种基于多级流表的功能组合方法

软件定义网络（Software-Defined Network，SDN）中的网络应用往往需要实现多种功能以满足上层业务需求，而如何对运行在控制器上的功能模块进行编排以完成数据包的多功能组合处理是一个仍待解决的问题.针对该问题，本文提出基于多级流表的功能并行和串行组合方案；其次，提出与任意多级流表交换机相适配的功能组合算法；最后，在Ryu控制器中添加功能组合模块并基于NetFPGA-10G节点完成了功能组合的原型实现.仿真实验与结果表明，与现有功能组合方案相比，所提功能组合方法降低了流处理时延及表项存储开销.

A Function Co mposition Method of Software-Defined Network Based on Multiple Tables

Network applications in Software-Defined Network (SDN)are always required to implement several func-tions to meet the network service demands,but how to arrange the function modules running on SDN controller to achieve multiple function packet processing is a problem to be solved.To compose the network functions,we introduced parallel and sequential composition schemes based on multiple tables;secondly,we put forward functional composition algorithms that can adapt with any multiple-table openflow switches;finally,we devised and implemented a Ryu-based control module which is used to do the function composition.Experimental results show that the method can reduce the storage cost and processing delay effectively compared with the existing schemes.