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。     

光传送网基于SDN的控制技术探讨

网络控制技术SDN正在进一步推动网络的可编程能力和开放性。SDN面向分组网络提出了控制架构和OpenFlow协议,但是并没有针对光交换提出成熟的控制方法。本文对比分析了潜在的传送网控制协议的优缺点,包括PCEP和OpenFlow,然后针对电路交换提出了针对OpenFlow的协议扩展方案,并探讨了光传送网络中基于控制器的潜在应用。     

华为发布协议无感知转发技术取得SDN技术重大突破

华为在软件定义网络（SDN）转发面技术上取得重大突破,首次在业界提出新的软件定义网络（SDN）转发面技术,命名为协议无感知转发（POF）,即转发硬件设备对数据报文协议和处理转发流程没有感知,网络行为完全由控制面负责定义。该技术作为对ONF OpenFlow协议的增强,拓展目前OpenFlow的应用场景,为实现真正灵活的可编程软件定义网络奠定基础。同时,华为还将于下周在美国举办的开放网络峰会上展示基于软件定义网络协议无感知转发（SDN POF）技术的设备原型样机。     

基于拓扑分域的光电混合网络控制研究

文中提出了一种将电层网络拓扑分域化的光资源提供方式,利用该思想设计了一种基于胖树网络的光电混合网络组网方案,结合软件定义网络架构与OpenFlow协议,设计并实现了网络控制器的连接管理、拓扑管理、流量监测模块。为解决传统网络设备不支持OpenFlow协议的缺陷,开发了一套基于Open vSwitch的网络设备代理,实现了OpenFlow协议与私有协议的转换,从而实现网络的统一化控制。最后对设计的方案进行了组网实验,实验结果表明,该方案能够有效地实现光网络与电网络的融合与协同工作,减轻电网络设备的工作负荷,提升网络整体性能;基于软件定义架构的网络体现出了良好的可编程特性,并能够实现网络资源的虚拟化和灵活调度。     

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。     

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     

思博伦发布集成式OpenFlow基准测试解决方案

全球网络、服务及设备测试领域的领导者思博伦通信日前宣布正式发布SpirentTestCenterOpenFlow，这将是业界第一种可同时提供协议仿真和高速以太网OpenFlow网络设备的流扩展能力及转发性能测试能力的解决方案。该解决方案能够必需的经验数据，用于确定OpenFlow网络设备和软件定义网络（SDN）应用是否能够在不影响用户体验的情况下实现真正的商业利益。     

OpenFlow网络测量分析系统的设计实现

OpenFlow网络目前缺少支持定量测量分析各种创新应用或机制的有效手段。以升级OpenFlow网络设备为具有本地日志功能的OpenFlow测量实体为基础,设计了一种基于集中式服务器控制测量实体进行分布式测量的机制,制定了其间的通信规程OpenFlow测量控制协议(OMCP),同时基于正则表达式、散列技术和可扩展的统计函数库等方式设计了一种分析测量日志的功能。原型系统的实验表明,OpenTrace服务器能够灵活部署和控制分布式测量任务,OpenTrace系统不仅能够定量地重现数据平面的数据流传输过程而且能够重现控制平面的控制事件交互过程,从而可为量化分析OpenFlow网络应用和新型机制提供广泛的性能数据。     

层次化软件定义光网络原型系统开发与试验演示

针对OTN的组网需求,提出了一种层次化的软件定义光网络控制结构,并采用商用OTN设备进行了试验测试和验证。本次试验在业界首次基于OpenFlow协议扩展实现了对多厂商OTN设备的统一控制管理,这种能力对于运营商在多厂商/多域网络环境中提供低成本、性能可控的端到端业务具有重要的价值。     

面向软件定义网络（SDN）的新型交换技术实验研究

本文主要内容是基于Mininet分别搭配POX和Floodlight的Linux实验测试平台,采用Python编程控制网络结构与控制器,并模拟多数据中心网络进行实验,通过Python编写网络拓扑结构,测试主机终端的带宽性能,最终使用Python脚本实现自动化测试节点、链路以及带宽等参数;使用FloodLight控制器对主机间的流表进行分析,深入理解OpenFlow协议。优化扩展了传统胖树结构的数据中心,测试数据结果相比传统结构测试更好;抓包分析建立OpenFlow流表的过程来更好的理解控制转发分离的思想。     

基于OpenFlow的未来互联网试验技术研究

对以OpenFlow为代表的基于可编程网络设备技术的未来互联网试验验证平台构建技术,以及OpenFlow自身的优势和不足进行了分析和研究,指出了OpenFlow是现阶段构建未来互联网试验验证平台的首要技术.     

New delay measurement method based on accurate timestamp in OpenFlow

At present,delay measurement methods in OpenFlow network have the disadvantage of excessive network resources and poor measurement accuracy.DeMon,an active mechanism to measure the delay of multiple paths between any two switch based on the controllable feature of individual traffic flow provided in OpenFlow was proposed.DeMon required only one probe packet to be send from controller,which was excepted to reduce the operational cost.Moreover,DeMon used OpenFlow switch instead of controller to get the timestamp of probe packet,making the measurement accuracy and stability have been greatly improved compared with other monitoring techniques in the OpenFlow network.     

基于OpenFlow网络的流媒体传输QoS的研究与设计

Open Flow是软件定义网络(Software Definded Network,SDN)的产物,是一种新型的网络结构,且发展十分迅速。但Open Flow网络的Qo S功能仍待优化,针对于Open Flow网络中流媒体传输Qo S的不足,在现有网络Qo S模式基础上提出了Open Qo S,它应用于Open Flow网络的控制器上,采用动态路由的方式,使得流媒体在网络端到端传输时,能够根据网络状况,动态改变路由路径,进而提高网络Qo S。最后,通过一个小的拓扑网络对本研究进行了试验验证。     

Research on the multicast mechanism based on physical-layer-impairment awareness model for OpenFlow optical network

A physical-layer-impairment (PLI)-awareness based optical multicast mechanism is proposed for OpenFlow controlled optical networks. This proposed approach takes the PLI models including linear and non-linear factors into optical multicast controlled by OpenFlow protocol. Thus, the proposed scheme is able to cover nearly all PLI factors of each optical link and to conduct optical multicast with better communication quality. Simulation results show that the proposed scheme can obtain the better performance of OpenFlow controlled optical multicast services.     

Moving target defense solution on network layer based on OpenFlow

In order to take an active part in network attack and defense,a moving target defense solution on network layer based on OpenFlow was proposed,using the flexibility of network brought by OpenFlow network architecture.On the network layer,through mapping the correspondent nodes’ addresses to pseudo-random virtual addresses in the LAN and mapping correspondent nodes’ ports to virtual ports,achieving the hiding of correspond nodes in the whole network and the information of network architecture.Researches verify the system’s effectiveness.Comparing with existing moving target defense solutions,the proposed algorithm can be deployed easily in the traditional network,and realize comprehensive protection of the corresponding in the whole network.     

Virtual networks: isolation, performance, and trends

Currently, there is a strong effort of the research community in rethinking the Internet architecture to cope with its current limitations and support new requirements. Many researchers conclude that there is no one-size-fits-all solution for all of the user and network provider needs and thus advocate for a pluralist network architecture, which allows the coexistence of different protocol stacks running at the same time over the same physical substrate. In this paper, we investigate the advantages and limitations of the virtualization technologies for creating a pluralist environment for the Future Internet. We analyze two types of virtualization techniques, which provide multiple operating systems running on the same hardware, represented by Xen, or multiple network flows on the same switch, represented by OpenFlow. First, we define the functionalities needed by a Future Internet virtual network architecture and how Xen and OpenFlow provide them. We then analyze Xen and OpenFlow in terms of network programmability, processing, forwarding, control, and scalability. Finally, we carry out experiments with Xen and OpenFlow network prototypes, identifying the overhead incurred by each virtualization tool by comparing it with native Linux. Our experiments show that OpenFlow switch forwards packets as well as native Linux, achieving similar high forwarding rates. On the other hand, we observe that the high complexity involving Xen virtual machine packet forwarding limits the achievable packet rates. There is a clear trade-off between flexibility and performance, but we conclude that both Xen and OpenFlow are suitable platforms for network virtualization.     

基于OpenFlow的SVC流媒体时延自适应分级传输方法

针对当前互联网流媒体传输的时延敏感性问题,提出一种基于OpenFlow的SVC（scalable video coding,可分级视频编码）流媒体时延自适应分级传输方法,该方法有效结合SVC流媒体可分级和OpenFlow灵活可编程的特性,在网络带宽受限和链路拥塞的复杂网络环境下,通过构建基础层和增强层2个独立路由,实现了动态网络下SVC流媒体分级自适应高效传输。仿真结果表明,该方法在提升SVC流媒体传输效率和质量,改善用户体验方面有重要作用。     

OSNR comprehensive-awareness model based lightpath control scheme in an OpenFlow controlled all-optical network

To enhance the communication quality of OpenFlow controlled all-optical networks, an optical signal-to-noise ratio comprehensive-awareness (OSNR-CA) model based lightpath control scheme is proposed. This approach transforms main physical-layer optical impairments into OSNR value, and takes this comprehensive OSNR value of the optical signal along the lightpath into consideration, when establishing the lightpath for the connection request using OpenFlow protocol. Moreover, the proposed scheme makes full advantages of the OSNR monitoring function in each node, and assigns the lightpath according to the comprehensive-OSNR value by extending messages of OpenFlow protocol, in order to guarantee the reliable establishment of the lightpath. The simulation results show that the proposed scheme has better performance in terms of packet loss rate and lightpath establishment time.