基于OpenFlow的SDN控制器关键技术研究

在SDN当中,控制器是重要的核心,对于底层转发设备,能够更好的进行控制和管理,将网络资源调用提供给上层应用。在SDN系统的运行当中,重要的基础和前提就是可扩展性、高效性、可靠性。在运营商网络当中,具有协议复杂、相对封闭、信息海量、规模庞大等特点,同时对网络的稳定性、可靠性等,都有着很高的要求。但是,传统的SDN控制器在实际应用中,难以很好的满足运营商网络的可靠性、高效性等要求,因此,需要对基于OpenFlow的SDN控制器关键技术进行研究。     

基于OpenFlow的SDN可靠性综述

软定义网络(SDN)是一种新型的网络架构,其将控制平面和数据转发平面分离,并为网络管理提供了可编程的接口,简化了网络管理。随着基于OpenFlow的SDN技术在现实中的广泛应用,其所存在的问题也凸显出来,可靠性就是其中的一个重要方面。文中针对基于OpenFlow的SDN在可靠性方面存在的问题,分析总结了导致OpenFlow网络失效的因素,将网络失效划分为控制器、链路和节点失效,并归纳出相应的解决方案,探讨了未来基于OpenFlow的SDN在可靠性方面的研究方向与趋势。     

基于OpenFlow的SDN网络中路由机制研究

首先介绍了SDN技术产生的原因、技术架构及其关键部件,然后分析了SDN网络和现有网络在路由互通,以及SDN网络内部如何最大限度利用网络传输资源等问题,提出了虚拟路由器的思想,并给出了详细的解决方案和主要实现过程。     

SDN控制平面的研究和分析

SDN是一种新型网络架构,其控制平面和数据平面相分离的思想,使得网络的运维、管理更为简单。控制平面作为SDN的控制核心,是整个SDN网络的关键所在。由于SDN控制器市场产品繁多,同时由于单控制器控制平面存在着可扩展性、可靠性等问题,研究组织和机构也纷纷提出了不同的分布式控制平面解决方案,这对SDN初学者和研究者造成了极大的困扰。为解决这个问题,文章详细介绍了当前主流的控制器,对控制器的各项参数进行分析,从而为研究人员和开发者选择控制器提供参考;并介绍了分布式控制平面设计方案,对分布式控制平面的研究方向做出了探讨。     

基于OpenFlow的SDN技术研究

作为一种新网络架构,SDN实现网络控制平面和数据平面分离,为未来互联网的发展提供一种新解决思路。文中简述OpenFlow与SDN技术的起源与发展,深入阐述SDN/OpenFlow技术的原理和技术标准,论述两大SDN标准制定组织ONF和OpenDayLight的发展现状,并给出SDN市场发展情况。     

基于OpenFlow的SDN测试技术的研究

当前,SDN产业蓬勃发展,特别是支持Open Flow协议的SDN交换设备得到了业界主流设备制造商的大力支持。然而,随着商用化应用的不断深入,SDN产业遇到了一些问题,如市场竞争紊乱、设备良莠不齐等。要推动SDN产业进一步向规范化和标准化的方向发展,就必须从测试工作入手,借鉴传统设备的测试经验,对SDN设备的测试方法和测试工具进行全面研究,找出符合SDN设备特点的测试技术。     

基于OpenFlow南向协议的SDN控制器性能测试方法及定量分析

随着软件定义网络(Software Defined Network,SDN)成为网络世界的新的范式转移,作为SDN网络的核心组件,控制器的性能得到了越来越多的关注。文章介绍了基于Open Flow 1.3这一南向协议的SDN控制器性能测试方法,并以某开源控制器为例,介绍测试结果的定量呈现方式和分析方法,为需要评估控制器性能的用户提供参考。     

基于园区网的SDN控制器设计研究

SDN网络将传统网络的控制平面和数据平面相分离的特点为未来网络的升级和演进提供了一种全新的思路。在SDN网络中,控制器具有举足轻重的地位,Open Flow则是其核心技术。文中根据园区网的特点和需求,设计了一款基于Open Flow的SDN控制器,可以实现对园区网的物理及虚拟网络管理并分析了基于园区网的SDN控制器性能。     

SDN技术在电信网络中应用的关键问题探讨

通过对软件定义网络(SDN)技术总体架构的分析,提出了SDN技术在电信网络中规模应用面临的4个方面的问题,包括数据平面构建问题、控制平面构建问题、与应用的整合问题以及如何在电信网络内平滑演进的问题。并参考业内主流的解决技术,给出了SDN技术应用在电信网络中的解决方案。     

基于SDN的服务链的设计与应用

随着信息技术的发展,互联网的发展日新月异.在互联网时代,人们的教育、娱乐和购物阵地已经转移,甚至工作方式也转移到网络平台[1].网络的稳定性、安全性成为大众关心话题,对网络维护提出了新的要求.本文将通过传统网络和以OpenFlow为核心的SDN服务链的对比研究,从而为实际网络部署提供有效参考.     

On Generality of the Data Plane and Scalability of the Control Plane in Software-Defined Networking

The control and data planes are decoupled in software-defined networking （SDN）, which enables both planes to evolve independently, and brings about many advantages such as high flexibility, programmability, and rapid implementation of new network protocols. However, in order to improve the scalability of the control plane at present, some control functionalities are added to the data plane, which is probably to impact on the generality of the data plane. The key challenge of adding control functionalities to the data plane is to strike a careful balance between the generality of the data plane and the scalability of the control plane. We propose some basic principles that both control and data planes should comply with, based on the evolutionary trend of SDN. Moreover, we take two approaches for reference according to the principles, viewed from the control messages in OpenFlow-based SDN. Our evaluations demonstrate that the approaches can maintain the generality of the data plane and improve the scalability of the control plane.     

SDN在IDC网络的应用方案研究

首先介绍了SDN的起源、概念及其对网络的影响。然后,详细阐述了IDC网络的使用需求,提出了基于SDN技术的解决方案,并通过对关键功能实现效果的对比,揭示了SDN技术在IDC场景下的优越性。最后,简述了SDN未来发展所面临的主要挑战。     

基于Mininet的SDN仿真与性能分析

SDN(Software Defined Network)是一种创新的网络构架,其核心理念是将控制平面和数据平面分离开来,将网络的管控集中到控制层面。OpenFlow作为南向接口标准提供了控制平面和数据平面分离的可能。文章从SDN的网络构架、SDN的硬件结构和OpenFlow协议对SDN进行了基本的分析,并采用mininet平台构建基于二层学习型交换机的简单防火墙,并对其进行仿真,交换机带宽测试值最高可达到1.09Gbps。     

A virtualized infrastructure to offer network mapping functionality in SDN networks

The separation of control and forwarding planes in software‐defined networking (SDN) networks is a key issue of the SDN technology. This feature and the existence of the SDN controller allow the developing of dynamic, adaptable and manageable networks, networks that require adequate services, and applications. However, the separation of these planes prevents the use of existing powerful tools that were coded considering traditional networks. In this paper, we make use of the potential of network virtualization (NV) technologies to propose the use of a virtualized infrastructure that makes possible the incorporation of these existing services and/or applications to an SDN network, without the need for programming additional and complex software modules in the SDN controller. Thus, in this paper, NV is not employed to develop a network managed by SDN but to broaden and give support to the SDN control layer. As an example, we describe the incorporation of nmap (a versatile and powerful tool widely used by security experts for network exploration) into the SDN framework. It is only necessary to develop a simple control plane service that thanks to the proposed virtualized infrastructure allows the inclusion of this powerful management application. The result offers the complete functionality of the nmap utility to the network administrators, who control the SDN network through the out‐of‐band control plane. In addition, a northbound REST API has been defined to offer the main functionality of the tool (host discovery, port scanning, and operating system detection) to the application layer.     

基于SDN的接入网安全解决方案设计

针对当前接入网中存在的主要安全问题,在总结分析现有的相应解决方案的基础上,结合SDN网络架构的特点及其相关技术,利用现有的安全机制,从组网安全的角度,提出一种基于SDN的接入网安全问题解决新方案,并详细描述了该方案的设计思想、总体架构及其通信流程。最后通过搭建实验环境进行测试,从而验证了该方案的可行性。     

基于SDN的量子密码通信网络设计与研究

软件定义网络(SDN)采用OpenFlow技术分离网络设备的数据平面和控制平面,实现灵活控制网络资源的目的。基于此,设计了量子密码通信网络模型,实现灵活控制密码通信网络整体量子密匙资源,确保了信息的安全传输。此外,提出了综合到端可用密匙和跳数的路由算法,提高了QKD生成密匙的有效利用率。由测试结果可知,通过基于SDN的量子密码通信网络及路由算法,可提高量子密匙资源利用率,提高网络性能。     

SDN特征剖析及典型应用介绍

通过与基于策略的网络管控、软交换等技术的对比,梳理了SDN技术源流,阐述了SDN体系结构及其包含的网络可编程、网络虚拟化等技术思想,剖析了其创新特征和对网络发展的意义;分析了SDN目前还缺乏清晰的商业模式、集中控制器存在状态收集和可伸缩性等问题,指出违背复杂系统管控规律所带来的局限性;介绍了SDN典型应用场景,说明SDN的适用范围主要是在局部自治网络中跨IP网、光网络、无线网络等层面进行一体化管控。     

Scalability of software defined network

With the development of software-defined networking (SDN),its scalability has become one of the most important issues of SDN.The features of SDN was studied which lead to its scalability problem when SDN was applied to large-scale network.The three main causes leading to scalability problem were discussed:control plane and data plane separation,logical centralized control and fine-grained flow control.Meanwhile,the studies which focus on the scalability of SDN from three aspects:scalability of performance,scalability of geographic and scalability of control was presented.Further,the studies on the performance evaluation of the scalability of SDN were introduced.Finally,the future work was discussed.     

Programmable virtual network instantiation in IaaS cloud based on SDN

A possible approach to cope with the diversity of future networks is to set up multiple isolated virtual networks on top of a single shared physical substrate, and each virtual network is customized to some specific purposes. However, in the current realization of virtualized infrastructure, the OpenStack infrastructure as a service (IaaS) cloud, whose isolation and programmability are limited in terms of scalability and performance. To overcome these limitations, we propose a solution based on software defined networking (SDN) which is composed of a centralized server and distributed agents. The server has complete view of the whole network substrate, and is responsible for the installation and management of virtual network through the distributed agents. Each agent has the local view of the substrate node. They can manage the local resources, dispatch and filter the inner- programmable virtual network (PVN) traffic based on MAC isolation which is more scalable than virtual local area network (VLAN) and more efficient than GRE. Our prototype implementation shows that this architecture is feasible and provides a better compromise between flexibility and performance than the solo centralized and distributed solutions.