SDN中一种基于多级流表的功能组合方法

软件定义网络（Software-Defined Network,SDN）中的网络应用往往需要实现多种功能以满足上层业务需求,而如何对运行在控制器上的功能模块进行编排以完成数据包的多功能组合处理是一个仍待解决的问题.针对该问题,本文提出基于多级流表的功能并行和串行组合方案;其次,提出与任意多级流表交换机相适配的功能组合算法;最后,在Ryu控制器中添加功能组合模块并基于NetFPGA-10G节点完成了功能组合的原型实现.仿真实验与结果表明,与现有功能组合方案相比,所提功能组合方法降低了流处理时延及表项存储开销.     

软件定义网络安全技术研究

随着网络规模的快速扩大及网络业务的多样化,原有的网络架构难以满足未来发展需要。软件定义网络(Software Defined Network,SDN)作为一种新兴技术,实现了控制面与数据面的解耦,能够提供网络的集中控制与流量的灵活调度,将引起通信领域的巨大变革。研究了SDN架构的特点及其面临的安全威胁;针对SDN安全技术研究现状进行了综述;从网络动态防御、软件定义监控和自身安全性增强3个方面提出了SDN安全技术的发展方向。在加强SDN自身安全性的同时提高了网络安全资源的动态调度能力。     

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。     

基于SDN的网络虚拟化仿真研究

软件定义网络的集中控制和可编程能力解决了传统网络虚拟化技术的弊端。为了进一步研究网络虚拟化技术,采用Mininet、OpenVirteX和Floodlight等软件,提出一种基于SDN的网络虚拟化仿真平台实现方案。总结了SDN网络和网络虚拟化特性,介绍了基于SDN的网络虚拟化仿真平台的系统架构,验证了其功能和隔离特性。提出的仿真平台为基于SDN技术的网络虚拟化创新提供了良好的平台支撑。     

SDN体系架构中元模型构建机制

微服务是现代应用架构的新方法,其特点在于将复杂的应用功能分解到离散、独立的服务中,以实现应用方案的解耦,并且各个服务可以单独开发、部署及扩展。应用的变化必然驱动着底层网络的变化,可重构基础网络体系架构旨在通过网络重构机制来弥补网络业务需求与网络基础传输能力之间的差距。融合可重构和软件定义网络技术,提出了一种SDN体系架构中元模型的构建机制,旨在将SDN体系架构中各层的服务以元模型的方式呈现,并且在借鉴AKF三维伸缩模型之后,提出了一种基于正交分解的元模型的构建方法。最后通过理论分析和开发实例,验证了基于正交分解的元模型构建方法的可行性。     

SDFAC：软件定义的流接入控制机制

SDN控制平面与数据平面分离的体系架构为实现细粒度的流管理以及灵活的中心化控制提供了基础。基于此,提出了一种软件定义的流接入控制机制SDFAC。首先从流的粒度对接入控制进行建模分析,给出了实现细粒度流接入控制所需要满足的条件;其次描述了SDFAC的基本框架和工作原理并设计了一种支持SDFAC功能的流鉴别协议;最后基于原型系统验证了SDFAC的可行性和可用性。     

基于SDN的卫星LTE融合网络及其性能仿真

软件定义网络技术SDN将网络控制功能与转发功能分离,使网络架构变得简明清晰。在简述传统卫星网络和地面LTE网络优势的基础上,概述卫星LTE星地融合网络,将SDN技术的核心思想引入卫星网络,提出基于SDN的卫星LTE融合网络架构,使用NS-3网络仿真软件实现对所提融合网络模型的仿真平台搭建,通过对不同场景下仿真数据的分析,评估所构建网络的性能,给出SDN卫星LTE融合网络的优势。     

基于OpenFlow技术的量子密码通信网络设计

软件定义网络(SDN)通过OpenFlow技术将网络设备的控制平面和数据平面分离开来,从而实现了对网络资源的灵活控制。文中设计了一种基于SDN的量子密码通信网络模型,实现了对整个密码通信网络中量子密钥资源的灵活控制,保证了信息传输的安全性。此外,还提出了一种同时考虑跳数和端到端可用密钥的路由算法,使得由QKD生成的密钥得到有效的利用。实际测试结果表明,基于SDN和所提出的路由算法,有效地利用了量子密钥资源,提高了网络的性能。     

面向数据中心异构SDN的网络协同编排平台设计与实现

软件定义网络（SDN）技术为高速发展的云计算提供了网络解决方案,而数据中心SDN的规模化部署必然带来SDN异构互通、统一管理和协同编排需求。在研究SDN异构互通、北向接口标准化和协同编排等关键技术及其发展现状的基础上,提出通过网络协同编排平台SDN Hub实现跨域、跨厂商、跨SDN控制器互通和互操作的方法,并给出了平台的方案设计和系统实现,最终实验结果证明,平台具备多控制器接入和异构资源池调度能力。     

SDN技术和产业分析及运营商应对策略建议

软件定义网络（SDN）提出了一种全新的网络设计理念,强调控制与转发的分离以及网络的可编程,实现网络架构的开放。SDN正和云计算一道重塑互联网网络模型和产业结构。介绍了SDN的基本概念、本质及特征,分析了SDN核心技术体系及其产业发展现状,从运营商视角探讨了SDN对未来网络的影响,并给出了相应的应用建议。     

Adaptive routing and wavelength assignment method based on SDN

Routing and wavelength assignment is an important resource allocation method of all-optical network.Aiming at the problem of traditional method combined with the new architecture,an adaptive multi-objective routing and wavelength assignment method based on SDN was proposed,which could realize the allocation of link resources of all-optical network through self-regulation.Based on the SDN service function chain model,service scheduling time and link service quality were taken as the scheduling objective,routing and wavelength assignment problem was constructed as the 0-1 integer programming problem,meanwhile,binary hybrid topology particle swarm optimization algorithm was used to optimize the network resources for optimal scheduling.The simulation results show that the proposed method is superior to the traditional classical algorithms in the test of recovery time,blocking rate and resource utilization.     

自治系统内IP子网和SDN子网的互联机制

SDN网络与传统IP网络的互联机制是当前学术界的研究热点,但现有解决方案并不能适用于所有应用场景。为此提出了一个基于OSPF协议的IMISA架构,在一个包含 SDN 子网（基于OpenFlow）和IP子网的自治系统范围内,通过给SDN控制器添加一个OSPF路由模块,利用OSPF协议交换各自的网络信息,最终实现了2种网络的互联。     

SDN based network resource selection multi-objective optimization algorithm

For the problem of coexistence of different resource utility objectives and mutual influence of resource selection strategies in the complex structure of software-defined network (SDN),an SDN based network resource selection multi-objective optimization algorithm was proposed.The optimization goals of resource providers and clients were taken into account in the algorithm,and a resource selection multi-objective optimization model was constructed.The model was further solved by the reference vector based multi-objective optimization algorithm.Simulation results show that compared with other algorithms,the proposed algorithm could quickly converge to the uniformly distributed non-inferior solution set,and balance the optimization objects of multi-party in SDN based resource access management.     

Emulating Software Defined Network using Mininet-ns3-WIFI Integration for Wireless Networks

SDN enables a new networking paradigm probable to improve system efficiency where complex networks are easily managed and controlled. SDN allows network virtualization and advance programmability for customizing the behaviour of networking devices with user defined features even at run time. SDN separates network control and data planes. Intelligently controlled network management and operation, such that routing is eliminated from forwarding elements (switches) while shifting the routing logic in a centralized module named SDN Controller. Mininet is Linux based network emulator which is cost effective for implementing SDN having in built support of OpenFlow switches. This paper presents practical implementation of Mininet with ns-3 using Wi-Fi. Previous results reported in literature were limited upto 512 nodes in Mininet. Tests are conducted in Mininet by varying number of nodes in two distinct scenarios based on scalability and resource capabilities of the host system. We presented a low cost and reliable method allowing scalability with authenticity of results in real time environment. Simulation results show a marked improvement in time required for creating a topology designed for 3 nodes with powerful resources i.e. only 0.077 sec and 4.512 sec with limited resources, however with 2047 nodes required time is 1623.547 sec for powerful resources and 4615.115 sec with less capable resources respectively.

     

自防御网络中客户端Agent的研究与实现

主要研究自防御网络计划中的网络准入控制功能。介绍自防御网络的概念、功能以及处于自防御网络最前端的部分-客户端Agent的功能;自防御网络系统的设计方法。重点介绍客户端Agent的设计以及其各个组成模块的功能、设计方法。最后搭建测试环境并进行测试,测试结果均达到预期的效果。     

Deep Learning Based Analog Beamforming Design for Millimetre Wave Massive MIMO System

Software-defined networking (SDN) is a new approach that overcomes the obstacles which are faced by conventional networking architecture. The core idea of SDN is to separate the control plane from the data plane. This idea improves the network in many ways, such as efficient utilization of resources, better management of the network, reduced cost, innovation with new evolution, and many others. To manage all these changes, there is a great need for an efficient controller to improve the utilization of resources for the better performance of the network. The controller is also responsible for the analysis and monitoring of real-time data traffic. There is a great need for a high-performance controller in networking industries, data centres, academia, and research due to the tremendous growth of distributed processing-based real time applications. Therefore, it is crucial to investigate the performance of an open-source controller to provide efficient traffic routing, leading to improved utilization of resources for the enhanced performance metrics of the network. The paper presents an implementation of SDN architecture using an open-source RYU SDN controller for the network traffic analysis. The proposed work evaluates the performance of SDN architecture based custom network topology for a node to node performance parameters such as bandwidth, throughput and roundtrip time, etc. The simulation results exhibit an improved performance of the proposed work in comparison to the existing default network topology for SDN.

     

Method for Overflow Attack Defense of SDN Network Flow Table Based on Stochastic Differential Equation

In order to avoid the overflow problem of network flow table caused by hackers attacking the network in the process of using the network, a method for overflow attack defense of SDN network flow table based on stochastic differential equation is proposed. In this method, the stochastic differential equation is first proposed, and the drift coefficient and diffusion coefficient of the equation are expanded and adjusted by Taylor. By using the limit theorem, the spillover attack of SDN network is weakly converged to an approximate two-dimensional Markov diffusion process, and the improved stochastic differential equation is obtained. Then, according to the stochastic nature of SDN network attack, the stochastic differential equation is transformed into an amplitude equation, which is based on the amplitude. The equation establishes a SDN attack detection scheme based on flow table statistics, which detects the spillover attacks of SDN network flow tables. Finally, according to the test results, it is proposed to use other switches instead of network flow table overflow switches to control the data upload rate, thus reducing the possibility of network crash and meeting the attack defense requirements of flow table overflow. The simulation results show that the proposed method has better detection performance and shorter running time, and can provide help for network security related work.

     

NFV业务链资源分配技术

SDN/NFV为运营商实现网络重构和架构演进提供了支撑技术,业务链及其组网技术是NFV的一个重要应用场景,相关的业务链资源分配问题是业界的研究热点。首先对业务链现状进行了梳理,重点分析了已有的资源分配机制和存在的问题,提出了一种业务链资源分配方案,充分考虑了对网络资源的优化利用,实现了VNF实例放置和业务链路径优化选择。实验结果表明,本方案具有更大的系统用户容量和更短的业务路径。     

Genetic algorithm‐based routing method for enhanced video delivery over software defined networks

Video streaming has emerged as a killer application in today's Internet, delivering a tremendous amount of media contents to millions of users at any given time. Such a heavy traffic load demands an effective routing method. In this paper, an effective routing method, named GA‐SDN, is developed based on software defined network (SDN) technique. To facilitate the researchers in this field to evaluate the video delivery quality over SDN, an evaluation framework and its associated source codes are provided. The framework integrates the H.264 Scalable Video coding streaming Evaluation Framework (SVEF) with the Mininet emulator. Through this framework, video processing researchers can evaluate their proposed coding algorithms in an SDN‐enabled network emulator, while network operators or executives can evaluate the impact of real video streams on the developing network architectures or protocols. Experiment results demonstrate the usefulness of myEvalSVC_SDN and prove that GA‐SDN outperforms traditional Bellman‐Ford routing algorithm in terms of packet drop rate, throughput, and average peak signal‐to‐noise ratio.