OpenFlow网络冗余控制报文消除机制研究  

Eliminating Redundant Control Messages in OpenFlow Networks

作　　者：左青云[1] 陈鸣[1] 丁科[1] 邢长友[1] 张国敏[1] 许博[1] 

机构地区：[1]解放军理工大学指挥信息系统学院,南京210007

出　　处：《计算机研究与发展》2014年第11期2448-2457,共10页Journal of Computer Research and Development

基　　金：国家"九七三"重点基础研究发展计划基金项目(2012CB315806);国家自然科学基金项目(61379149;61070173;61103225)

摘　　要：OpenFlow网络数据平面将未匹配流表的数据包发送给控制器,其中的无连接突发流量将产生冗余控制报文,对网络性能造成不良影响,而目前的OpenFlow协议并未对此进行处理.研究了在控制平面和数据平面分别消除冗余控制报文的方法 ERCMC(eliminating redundant control messages on the control plane)和ERCMD(eliminating redundant control messages on the data plane),分别在NOX和Open vSwitch上进行实现,并进行性能评价.实验结果表明,ERCMC方法能够消除冗余控制报文,但增加了额外的处理开销;ERCMD方法在减少冗余控制报文数量的情况下能够减小控制器和OpenFlow交换机负载.The data plane of OpenFlow networks sends packets which don＇t match any flow entry to the controller, and in such case connectionless burst traffic is encapsulated as control messages, until the data plane receives a response message from the controller. This process produce redundant control messages for both the control and data planes, which influences the performance of the entire network. However, current OpenFlow protocol doesn＇t give definite explanation or handle this problem. In this paper, we propose two approaches of eliminating redundant control messages on the control plane （referred as ERCMC） and on the data plane （referred as ERCMD）. ERCMC constructs latest packet in message view （referred as LPMV） on the controller to mark the latest packet-in messages, so as to eliminate redundant control messages on the control plane. ERCMD adds marks directly on the data plane, so that the burst packets are directly buffered and never encapsulated as control messages. We implement these two approaches in NOX and Open vSwitch respectively, and evaluate the performance of the two approaches. The results of our experiments show that ERCMC can eliminate redundant control messages, but it will add extra processing overheads; ERCMD can not only eliminate redundant control messages, but also alleviate the load of the controller and OpenFlow switches.

关 键 词：OpenFlow网络 OpenFlow协议 控制报文 UDP流 控制器 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]