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。     

基于OpenFlow的SDN控制平面可扩展性综述

OpenFlow发展之初,主要是为了校园网络研究人员设计其创新网络架构提供真实的实验平台,形成一种新的网络构架SDN。随着其应用范围的增加,遇到的问题逐渐显现出来,尤其是可扩展性方面。文中介绍了OpenFlow的产生背景、特点及发展现状,以及几种较为典型的SDN控制器模型和控制平面框架,并对SDN可扩展性方面遇到的问题及解决方案进行了分析,并概述了其今后的发展方向。     

基于OpenFlow的软件定义网络路由技术研究

文中主要探索了基于OpenFlow的软件定义网络（SDN）路由技术,旨在优化和提高网络管理效率。通过深入解读SDN的核心构架、OpenFlow协议的关键组成,并将其与传统路由进行对比,发现SDN提供了一个更加灵活和集中的网络管理机制。在路由决策、性能优化和故障恢复上,基于OpenFlow的SDN明显优于传统方法。由此可见,基于OpenFlow的软件定义网络路由技术不仅可以大大提高网络的运行效率,还能简化网络管理流程,为未来的网络技术发展指明方向。     

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。     

迎接SDN/OpenFlow网络测试的挑战

新出现的网络部署场景,例如超大规模数据中心内的虚拟化和云环境,都会使现有的网络技术和架构不堪重负。ONF执行总裁DanPitt描述了传统联网技术面临的3项关键挑战,即成本、敏捷性和设计。事实证明,联网的新方法,即所谓的软件定义联网(SDN)和相关的协议OpenFlow,能够应对这些挑战,并且解决更多的问题。然而,尽管SDN和OpenFlow具备巨大的潜力,但它们仍然会对包括网络测试在内的网络生态体系中的许多方面造成干扰。思博伦通信的《迎接SDN/OpenFlow网络测试的挑战》一文首先对SDN和OpenFlow进行了介绍,然后对其所带来的优势进行了阐述,最后对如何迎接SDN和OpenFlow网络测试的挑战给出了解决方案。     

基于OpenFlow的虚拟网实现研究

软件定义网络是一种数据和控制平面分离、软件可编程的新型网络架构及技术,控制平面使用以OpenFlow为代表的协议对转发平面进行集中式控制。SDN架构的这些特点能很好地满足了云计算对虚拟网络的集中化、标准化、自动化的配置管理要求。针对传统虚拟网络技术支持云计算平台的不足,提出基于OpenFlow的SDN技术设计虚拟网络的思路,论述了几种虚拟网络实现的原理与处理流程,并给出了模块化的软件设计及部分关键代码功能描述。     

SDN网络及其在流媒体领域的应用探索

一项新的网络技术正在声名鹊起,那就是SDN,即软件定义网络。SDN把网络系统的控制平面与数据转发平面进行了分离,使网络建设更加快捷、成本更低、利用率更高、维护更方便。这一新网络建设模式的出现,将给网络技术架构、网络建设带来一场新的变革,也将为流媒体网络建设和视频服务带来非常大的影响;本文从技术架构、优点与挑战、在流媒体业务中的应用,以及OpenFlow协议等几个方面对SDN做了较为详细的介绍。     

基于OpenFlow的网络虚拟化技术研究应用

从OpenFlow、SDN技术诞生至今,国内外研究机构在诸如部署完全可控、可定制网络实验平台、可编程虚拟化路由技术和NOX网络操作系统等方面取得了一定进展。对目前国内外基于OpenFlow技术的网络虚拟化领域的相关研究成果进行分析总结,将其与NFV技术进行简要对比,并对OpenFlow技术在未来科研实验领域更广泛的应用和研究方向进行展望。     

思博伦开发OFTest一致性测试套件

全球网络、服务和设备测试领域的领导者思博伦通信日前宣布,公司已经与印地安纳大学的SDN/OpenFlow研究机构——InCNTRE建立了伙伴关系,共同开发OFTest的一致性测试套件。OFTest是一种基于开放源代码的OpenFlow网络测试解决方案。当其与Spirent TestCenter OpenFlow性能测试解决方案结合在一起后,将有助于推动OpenFlow和     

对基于OpenFlow的SDN技术分析

基于OpenFlow的软件定义网络技术(SDN)技术可以为新的网络应用与未来互联网技术的发展提供支持。本文主要对基于OpenFlow的SDN技术的关键组件、系统架构、OpenFlow的运作模式、基于OpenFlow技术的应用进行了探究,并在此基础上论述了相关领域的研究重点与发展趋势。     

Stateful firewall‐enabled software‐defined network with distributed controllers: A network performance study

SummarySoftware‐defined network (SDN) is constructed by decoupling the control and data plane from the forwarding devices. The control plane operations are managed by centralized or distributed controllers, and the data plane operation is managed by respective forwarding devices. SDN provides an easy and efficient management solutions for software‐programmed consolidated middlebox in virtual machines. Additionally, SDN with centralized controller faces complications like scalability, network bottle neck, and single point failure. In this study, a stateful inspection firewall acts as a middlebox in distributed SDN‐controlled network. The controller is programmed with a failure detection and recovery mechanism to provide reliability and redundancy and enhance the overall performance of the network. The objective of stateful firewall on SDN architecture is to secure the network by monitoring the current connections and maintain its state information until the connection is active. In this paper, the performance of firewall‐enabled SDN with centralized and distributed controllers are measured, compared, and analyzed. The experiments are done using POX controller, and the results are verified by Mininet network emulation tool. The results show that the stateful firewall‐enabled SDN with distributed controller network improves the security, reliability, availability, and overall performance of the network. In the proposed SDN, average network throughput is improved by 43%, average network delay is reduced by 4%, average channel utilization is increased by 40%, average network overhead is reduced by 26%, and average network response time is reduced by 23%.     

浅谈软件定义网络中数据平面的通用性和控制平面的可扩展性(英)

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.     

软件定义网络中可靠性优化控制器的位置研究(英)

By decoupling control plane and data plane,Software-Defined Networking(SDN) approach simplifies network management and speeds up network innovations.These benefits have led not only to prototypes,but also real SDN deployments.For wide-area SDN deployments,multiple controllers are often required,and the placement of these controllers becomes a particularly important task in the SDN context.This paper studies the problem of placing controllers in SDNs,so as to maximize the reliability of SDN control networks.We present a novel metric,called expected percentage of control path loss,to characterize the reliability of SDN control networks.We formulate the reliability-aware control placement problem,prove its NP-hardness,and examine several placement algorithms that can solve this problem.Through extensive simulations using real topologies,we show how the number of controllers and their placement influence the reliability of SDN control networks.Besides,we also found that,through strategic controller placement,the reliability of SDN control networks can be significantly improved without introducing unacceptable switch-to-controller latencies.     

一种基于数据平面可编程的软件定义网络报文转发验证机制

针对软件定义网络(SDN)中OpenFlow协议匹配字段固定且数量有限,数据流转发缺少有效的转发验证机制等问题,该文提出一种基于数据平面可编程的软件定义网络报文转发验证机制。通过为数据报文添加自定义密码标识,将P4转发设备加入基于OpenFlow的软件定义网络,在不影响数据流正常转发的基础上,对网络业务流精确控制和采样。控制器验证采样业务报文完整性,并针对异常报文下发流规则至OpenFlow转发设备,对恶意篡改、伪造等异常数据流进行转发控制。最后,构建基于开源BMv2的P4转发设备和基于OpenFlow的Open vSwitch转发设备的转发验证原型,并构建仿真网络进行实验。实验结果表明,该机制能够有效检测业务报文篡改、伪造等转发异常行为,与同类验证机制相比,在安全验证处理开销保持不变的情况下,能够实现更细粒度的业务流精确控制采样和更低的转发时延。     

Nature‐inspired meta‐heuristic algorithms for solving the load balancing problem in the software‐defined network

The growth of the networks has difficult network management. Recently, a concept called software‐defined network (SDN) has been proposed to address this issue, which makes network management more adaptable. Control and forwarding planes are separated in SDN. The control plane is a centralized logical controller that controls the network. The forwarding plane that consists of transfer devices is responsible for transmitting packets. Because the network resources are limited, optimizing the use of resources in the networks is an important issue. Load balancing improves the balanced distribution of loads across multiple resources in order to maximize the reliability and network resources efficiency. SDN controllers can create an optimal load balancing compared to traditional networks because they have a network global view. The load‐balancing problem can be solved using many different nature‐inspired meta‐heuristic techniques because it has the NP‐complete nature. Hence, for solving load balancing problem in SDN, nature‐inspired meta‐heuristic techniques are important methods. However, to the best of our knowledge, there is not a survey or systematic review on studying these matters. Accordingly, in the area of the load balancing in the SDN, this paper reviews systematically the nature‐inspired meta‐heuristic techniques. Also, this study demonstrates advantages and disadvantages regarded of the chosen nature‐inspired meta‐heuristic techniques and considers their algorithms metrics. Moreover, to apply better load balancing techniques in the future, the important challenges of these techniques have been investigated.     

SDN/NFV‐based handover management approach for ultradense 5G mobile networks

With the great increase of connected devices and new types of applications, mobile networks are witnessing exponential growth of traffic volume. To meet emerging requirements, it is widely agreed that the fifth‐generation mobile network will be ultradense and heterogeneous. However, the deployment of a high number of small cells in such networks poses challenges for the mobility management, including frequent, undesired, and ping‐pong handovers, not to mention issues related to increased delay and failure of the handover process. The adoption of software‐defined networking (SDN) and network function virtualization (NFV) technologies into 5G networks offers a new way to address the above‐mentioned challenges. These technologies offer tools and mechanisms to make networks flexible, programmable, and more manageable. The SDN has global network control ability so that various functions such as the handover control can be implemented in the SDN architecture to manage the handover efficiently. In this article, we propose a Software‐Defined Handover (SDHO) solution to optimize the handover in future 5G networks. In particular, we design a Software‐Defined Handover Management Engine (SDHME) to handle the handover control mechanism in 5G ultradense networks. The SDHME is defined in the application plane of the SDN architecture, executed by the control plane to orchestrate the data plane. Simulation results demonstrate that, compared with the conventional LTE handover strategy, the proposed approach significantly reduces the handover failure ratio and handover delay.     

软件定义的无人机网络架构研究综述

软件定义网络（Software Defined Network,SDN）依靠着其集中控制、可编程性和数控分离等优点,能够有效解决无人机网络（Flying Ad Hoc Network,FANET）面临的任务拓扑高度变化、网络链路连接不稳定、网络安全防护脆弱以及应用程序的异构性等问题,极大地提升FANET的灵活性和可靠性。针对SDN架构与FANET的结合问题,描述了SDN的体系架构,并以SDN控制器部署方式为关注点分类别概括了近几年软件定义无人机网络（Software-defined Flying Ad Hoc Network,SD-FANET）的研究进展,重点阐述了结合移动边缘计算（Mobile Edge Computing,MEC）的SD-FANET研究现状,最后指出了SD-FANET的应用场景和一些具体的未来研究方向。     

Research on software-defined network and the security defense technology

Software-defined network (SDN) separated the traditional control plane from the data plane,formed a centralized controller,opened up the network programming interface,simplified network management,promoted network innovation and optimized network operation.However,SDN's “three-layer two-interface” architecture increased the network attack surface,resulting in many new security issues.The development,characteristics and working principle of SDN were first introduced,and the existing security problems from the application layer,the northbound interface,the control plane,the southbound interface,the data plane were summarized respectively.Secondly,the latest research progress and existing solutions were discussed.Finally,SDN current and future security challenges were summarized,and the future SDN security development direction was looked forward to.