SDN中的网络拓扑发现

Network Topology Discovery in SDN

随着网络负载的不断增大,传统网络体系架构已难以适应时代需要。为了解决传统网络面临的问题,一种新型的网络体系结构——软件定义网络(saftware defined networking,SDN)应运而生。数据平面和控制平面的分离是这种新型网络体系架构的主要特点。为使SDN能够方便快捷地配置和管理网络,需要控制器能够实时地获取网络状态信息,尤其是拓扑信息。因此,拓扑发现模块是SDN重要的组成部分。首先,介绍了SDN的相关原理以及拓扑发现方法;然后,对传统的方法提出了改进,通过向交换机加入新的规则,减少与控制器之间的消息传递数量,在原有功能的基础上降低网络的负载,达到提升网络性能的目的。

With the increasing load of the network,the architecture of traditional network is difficult to adapt to today’s needs.To solve the problems faced by the traditional network, a new network architecture named software defined networking （SDN） is supported.The separation of data plane and control plane is the main feature of this new network architecture.In order to facilitate the configuration and management of SDN, the controller needs to be able to obtain real-time network status information, especially topology information.Therefore the topology discovery module is an important part of SDN.The paper introduces the relevant principle and topology discovery method of SDN at first. And then the paper puts forward improvement on the current method of topology discovery.By adding new rules to the switch, the amount of messaging between the controller and the switch can be reduced. And the load of the network can also be reduced.So the method can improve the network performance.