软件定义网络中的动态负载均衡与节能机制  

Dynamic Load Balancing and Energy Saving Mechanism in Software Defined Networking

作　　者：鲁垚光 王兴伟 李福亮 黄敏[2] LU Yao-Guang;WANG Xing-Wei;LI Fu-Liang;HUANG Min(College of Computer Science and Engineering,Northeastern University,Shenyang 110169;College of Information Science and Engineering,Northeastern University,Shenyang 110819)

机构地区：[1]东北大学计算机科学与工程学院,沈阳110169 [2]东北大学信息科学与工程学院,沈阳110819

出　　处：《计算机学报》2020年第10期1969-1982,共14页Chinese Journal of Computers

基　　金：国家重点研发计划项目(2019YFB1802802);国家自然科学基金项目(61572123,61872073);教育部-中国移动科研基金项目(MCM20160201)资助.

摘　　要：软件定义网络(Software Defined Networking,SDN)作为一种新型的网络范式,解决了网络协议臃肿、网络创新困难等问题,但仍面临着诸多挑战如负载均衡与节能.为了应对这一挑战,本文设计了一种动态机制用以解决SDN面临的负载均衡与节能问题.首先,本文提出SDN负载均衡与节能机制的框架.整个框架分为流量监测机制、路由和流调度机制、OpenFlow协议部分和基础设施部分.其中,流量监测机制负责监控网络近似实时的状态,实现数据流级别的流量测量;路由和流调度机制负责在对即将休眠或可能出现拥塞的链路进行流调度;OpenFlow协议负责控制平面和数据平面之间的交互;基础设施部分在转发数据的同时负责数据流路径快速地安装和更新.其次,本文设计了一种基于网络整体流量和数据流速率变化的动态轮询算法,实现了以较小的开销获得流级别的流量测量.然后,本文提出一种基于链路偏好的随机路由算法和两种流调度算法以实现SDN的动态负载均衡与节能.在路由算法中,本文综合负载均衡与节能两个因素,将链路利用率映射为链路的偏好,根据链路的偏好对链路上的流量进行调控,进而使得数据流在路由阶段就能实现负载均衡与节能.这种映射关系随着网络的流量以及链路的利用率动态变化,体现了路由机制良好的动态性.此外,两种流调度算法实现对网络中拥塞链路和空闲链路的流调度,进而达到均衡网络负载和节能的目的.最后,基于Ryu控制器和Mininet平台对SDN中的动态负载均衡与节能机制进行了仿真实验.实验结果表明,本文设计的机制在实现负载均衡的同时最高可节能25%左右,并且在链路平均利用率和能效等多个指标上,明显优于对比机制.As a new type of network paradigm,Software Defined Networking(SDN)decreases the complexity of network and improves the power of network innovation,but still has many challenges especially the load balance and energy saving.Therefore,a dynamic mechanism to solve the problem of load balancing and energy saving in SDN is proposed in this paper.Firstly,the framework of load balancing and energy saving mechanism for SDN is proposed.The framework includes many function modules,including traffic monitoring,routing and flow scheduling,OpenFlow protocol and infrastructure.Among them,traffic monitoring aims at monitoring the near-real-time network status,and achieving traffic measurement at the level of flow;routing and flow scheduling aim at scheduling the flows for the links that may enter into sleep mode or encounter congestion;OpenFlow protocol aims at guaranteeing the communication between the control plane and the data plane;infrastructure provides the basis for data transmission,and at the same time aims at quickly installing and updating the data flow paths.Secondly,a dynamic polling algorithm based on the change of the whole network traffic and flow rate is designed for traffic monitoring,which could measure the traffic at the level of data flow with a low cost.Then,this paper proposes a random routing algorithm based on link preference and two flow scheduling algorithms to achieve dynamic load balancing and energy saving for SDN.In the routing algorithm,with the consideration of both load balancing and energy saving,the link utilization is converted to link preference,according to which the traffic on link is controlled,so that load balancing and energy saving can be achieved at the stage of routing.This relation between link utilization and preference can be adjusted dynamically to match network traffic or link utilization,reflecting the dynamic advantage of this mechanism.In addition,two flow scheduling algorithms perform flow scheduling on congested and idle links in the network,thereby achieving the purpose o

关 键 词：负载均衡 节能 软件定义网络 链路偏好 流调度 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]