基于NetFPGA的硬件路由器的实现

路由器是网络架设中必不可少的构建组件,在路由器构成中重要的就是NetFPGA网络硬件平台。该硬件平台具有可重构性,并且模块化程度较高,更是一种开放型平台,用户能够根据所需构建多种网络应用。基于NetFPGA的硬件路由器就是在其平台上利用模块化思想完成路由器构建的方法,并对路由器进行了功能验证,证实其可行性和安全可靠性。     

基于NetFPGA的网络数据流量采集器

为解决基于软件的流量采集方法无法在高速网络环境下准确测量的问题,提出了一种基于NetFPGA的网络数据流量采集器,以达到实时在线的流量统计和采集功能。该系统采用模块化的架构设计,通过硬件实现功能的方式提高网络测量精度。实验结果表明,该系统能准确统计出网络中93%以上流量。     

RIP和OSPF路由协议在Click软件路由器中的实现

Click是一种模块化的软件路由器体系结构,基于该体系结构用户可以根据自己的需求搭建不同功能的路由器.针对Click软件路由器支持静态路由协议的局限性,引入模块化路由器软件协议栈XORP(eXtensible Open Router Platform),实现了动态路由协议在Click软件路由器上的扩展.通过搭建实验网络拓扑环境,验证了基于Click转发平台的两种不同的动态路由协议RIP和OSPF,并进行了相关测试和性能分析.实验结果表明,Click软件路由器的转发性能与Linux内核基本一致,但相比较而言,Click软件路由器具有灵活、可扩展、模块化等不可比拟的优势.     

一种向量网可编程交换机实现*

向量网是一种以向量地址为基础的新型数据通信网络。向量网硬件交换机的主要功能是根据向量地址转发向量数据包，是决定组网成本的重要硬件设备。提出一种完整的向量网硬件交换机设计，并在NetFPGA平台实现。结果表明，在完成功能的前提下，该方案可完全移植到Xilinx Spartan-3A系列的XC3S1400A芯片，其成本远低于同等性能IP网路由器。     

快速自适应调频机制及其在NetFPGA上的实现

降低网络设备能耗已经成为当前研究的热点.文中,作者设计了一种能够实时适应流量变化的动态自适应频率调整方法FASS,它能根据处理模块的负载,实时地调整模块的工作频率,从而有效降低模块的能耗.同时,作者通过修改NetFPGA的参考路由器设计,将FASS添加到数据包处理模块中来验证FASS的性能.马尔可夫模型分析结果和实际实验的测试结果表明,在仅增加可容忍的延迟的情况下,FASS在多种不同的负载情况下,都能有效地降低模块功耗.另外,作者的工作说明FASS可以应用于实际的物理设备中以实现节能.     

基于Click系统的IPv6模块化软件路由器

Click是一种新型模块化的软件路由器。以Click的体系结构为基础,文章论述了IPv6模块化软件路由器的组成,设计并实现了其原型系统,配置了Click文件,并进行了测试。     

DCT硬件实现的通用性探究

在分析了DCT的原理以及采用蝶形快速算法的实现方法的基础上,提出一种可以实现不同尺寸模块调用的方法.为了达到减少硬件实现上复杂度的目的,DCT处理器采用模块化的思想,将系统划分为不同的功能模块,这样在提高硬件电路通用性的同时增强了DCT在实际应用中的灵活性.使用Verilog HDL硬件描述语言进行参数化RTL级描述,在SUSE Linux环境下的NC-Launch软件上进行仿真验证.实验验证了所设计模块功能上的正确性.在应用中,本设计能提高硬件电路的通用性和DCT的灵活性.     

模块化可变形机器人控制系统设计与变形方法研究

介绍了模块化可变形机器人控制系统的整体结构．控制系统的硬件和软件均采用了模块化结构的设计,增强了整个系统的可扩展性和容错性．针对该机器人的机构特点提出了一种新的变形方法——协同变形法．实验验证了控制系统的有效性和协同变形法的优越性．     

支持ForCES的分布式IP路由器技术研究

从组成路由器的控制件和转发件两类基本模块来看,下一代的IP路由器需要做很大的改进。文章提出了一种分布式的模块化的路由器架构,讨论了控制件和转发件的实现机制,给出了Linux下的具体实现,并在最后构建了基于网络处理器的分离模块路由器。     

一种用于可扩展路由器的报文结构设计

路由器的发展需要可扩展路由器体系结构。本文设计和买现了一种用干可扩展路由器的报文结构。新的报文结构在方便实现路由器模块化，提高报文访问性能，减少模块问内存拷贝，实现报文结构容错性等方面具有显著优势。     

基于多样化业务需求的多态路由模型研究

针对结构固定僵化、功能单一的传统路由机制不能有效适应多样化业务需求这一问题,提出了一种路由功能与业务需求自适配的多态路由模型,为支持多样化业务需求提供个性化定制路由服务,并设计实现了多态路由原型系统。该系统采用可编程路由器软件开源控制平台Quagga、可编程NetFPGA -10G平台作为控制平面和数据平面,通过虚拟化技术以及灵活可编程的数据平面结构实现多种路由协议的共存,并基于NetFPGA-10G平台设计实现了多态路由原型系统。测试实验证明,多态路由系统在保证业务的服务质量方面有很大提升,支持业务定制个性化的路由服务路径,并且转发速率、丢包率以及传输带宽等性能都有提高。     

Online NetFPGA decision tree statistical traffic classifier

Classifying online network traffic is becoming critical in network management and security. Recently, new classification methods based on analysis of statistical features of transport layer traffic have been proposed. While these new methods address the limitations of the port based and payload based traffic classification, the current software-based solutions are not fast enough to deal with the traffic of today’s high-speed networks. In this paper, we propose an online statistical traffic classifier using the C4.5 machine learning algorithm running on the NetFPGA platform. Our NetFPGA classifier is constructed by adding three main modules to the NetFPGA reference switch design; a Netflow module, a feature extractor module, and a C4.5 search tree classifier. The proposed classifier is able to classify the input traffics at the maximum line speed of the NetFPGA platform, i.e. 8 Gbps without any packet loss. Our method is based on the statistical features of the first few packets of a flow. The flow is classified just a few micro seconds after receiving the desired number of packets.     

A new power profiling method and power scaling mechanism for energy-aware NetFPGA gigabit router

Today the ICT industry accounts for 2–4% of the worldwide carbon emissions that are estimated to double in a business-as-usual scenario by 2020. A remarkable part of the large energy volume consumed in the Internet today is due to the over-provisioning of network resources such as routers, switches and links to meet the stringent requirements on reliability. Therefore, performance and energy issues are important factors in designing gigabit routers for future networks. However, the design and prototyping of energy-efficient routers is challenging because of multiple reasons, such as the lack of power measurements from live networks and a good understanding of how the energy consumption varies under different traffic loads and switch/router configuration settings. Moreover, the exact energy saving level gained by adopting different energy-efficient techniques in different hardware prototypes is often poorly known. In this article, we first propose a measurement framework that is able to quantify and profile the detailed energy consumption of sub-components in the NetFPGA OpenFlow switch. We then propose a new power-scaling algorithm that can adapt the operational clock frequencies as well as the corresponding energy consumption of the FPGA core and the Ethernet ports to the actual traffic load. We propose a new energy profiling method, which allows studying the detailed power performance of network devices. Results show that our energy efficient solution obtains higher level of energy efficiency compared to some existing approaches as the upper and lower bounds of power consumption of the NetFPGA Openflow switch are proved to be 30% lower than ones of the commercial HP Enterprise switch. Moreover, the new switch architecture can save up to 97% of dynamic power consumption of the FPGA chip at lowest frequency mode.     

Improved parallelism and scheduling in multi-core software routers

Recent technological advances in commodity server architectures, with multiple multi-core CPUs, integrated memory controllers, high-speed interconnects, and enhanced network interface cards, provide substantial computational capacity, and thus an attractive platform for packet forwarding. However, to exploit this available capacity, we need a suitable software platform that allows effective parallel packet processing and resource management. In this paper, we at first introduce an improved forwarding architecture for software routers that enhances parallelism by exploiting hardware classification and multi-queue support, already available in recent commodity network interface cards. After evaluating the original scheduling algorithm of the widely-used Click modular router, we propose solutions for extending this scheduler for improved fairness, throughput, and more precise resource management. To illustrate the potential benefits of our proposal, we implement and evaluate a few key elements of our overall design. Finally, we discuss how our improved forwarding architecture and resource management might be applied in virtualized software routers.     

通过宽带路由器搭建FTP服务器

本文描述的通过宽带路由器搭建FTP服务器的方法是基于ADSL 路由器的上网模式,使用的硬件路由器产品是TL-R860/R860M.搭建FTP服务器是通过配置SERV-U软件,采用WIN XP操作系统作为运行平台.论文较为详细的介绍了服务器软件SERV-U安装配置.实验结果表明这种通过宽带路由器搭建FTP服务器架构的方法简单易学且易于控制.     

基于V4L2的无线视频传输系统的设计

提出了一种基于V4L2的无线视频传输系统的设计方法.路由器端和客户端的设计以S3C2440为硬件平台,以Linux操作系统为软件平台,以QT为图形化界面应用程序开发软件.将采集到的图像数据按MPEG-4标准进行编码,得到的码流通过路由器端中soft-AP构建的无线网络进行传输.客户端可实时地获得视频图像,从而实现实时视...     

硬件构件的形式化描述及其组装机制

针对构件化的路由交换平台设计,提出硬件基础构件的抽象模型及其内部处理流程的形式化描述,提取出顺序、并行、分支以及聚合4种原子组装机制,用于构建更高层次的复合构件,并推导出复合构件抽象模型及其处理流程的形式化描述,从而有利于抽象出更大粒度的构件用以组装复杂的硬件平台。     

基于路由器的开源嵌入式操作系统学习平台

摘要：针对现有嵌入式操作系统学习中存在的问题,设计了一种既适合基本理论学习,又可以进行高级开发实践的学习平台。通过对WRT54GL路由器硬件的简单改造,使其成为学习开源OpenWrt和Xinu操作系统的优秀平台。平台设计简单易行,简繁得当,费用低廉,是嵌入式操作系统学习的一个好的选择。