虚拟化平台下二层网络问题研究

云计算引入了”资源池”的概念,打破了单台服务器的限制,将数据中心中CPU和内存\板卡等资源整合起来,能够灵活地组合以满足用户需求.虚拟化技术是建设资源池的主要手段,虚拟化技术通过部署以Hypervisor和vCenter为代表的虚拟化软件,能大幅提高单台物理服务器的资源利用率。但随着虚拟化技术的引入,在单台服务器上虚拟出多个VM,无可避免的会造成网络层次增加,并由此引发出路由环路,广播风暴,单点故障,网络延迟、布线杂乱等各种问题。本文根据虚拟化平台建设过程中的一些经验,总结了虚拟化平台下网络架构需要注意的事项,并结合业界最新的技术趋势,探索虚拟化平台下网络的构想。     

超融合架构在运营商IT支撑系统建设中的应用

超融合架构是将计算资源和存储资源整合到同一套单元设备(如X86服务器)中,通过在物理服务器上运行虚拟化软件,在虚拟化软件上运行分布式存储服务供虚拟机使用. 分布式存储可以运行在虚拟化软件上的虚拟机里,也可以是与虚拟化软件整合的模块,除了虚拟化计算和存储,超融合架构还可以整合网络以及其它更多的平台和服务,将计算、网络和存储都集成在一个设备内,将计算资源与存储资源相融合,每个节点同时兼具提供计算资源与存储资源的角色,也就是“Infrastructure in a box”的理念,即“一箱即云”,是实现软件定义数据中心的终极技术途径.     

计算机网络安全中虚拟网络技术的应用

虚拟化抽象物理资源,消除物理设备局限性对信息处理的制约,尤其是在结合网络技术下,将大幅度增强虚拟化系统在信息处理上的广泛性、安全性、高效性以及可拓展性。在推动虚拟网络技术在计算机网络安全中的应用时,有必要在应用虚拟网络技术时,从网络层、设备层、软件层以及升级优化等方面强化计算机网络安全。     

网络功能虚拟化网络功能虚拟化:基于虚拟化的中间件盒子

基于虚拟化的中间件盒子的模型,采用x86架构的电脑硬件设备,依托虚拟化平台构建了一种集成了路由器、语音服务器、虚拟桌面等服务的虚拟中间件盒子。该虚拟中间件盒子采用了中间件盒子的概念,即在标准的服务器上运行开源的虚拟化平台,如XEN、KVM等,并运用网络功能虚拟化(NFV)的理念和软件定义网络(SDN)的理念进行控制管理,最终实现为每个组织、企业、个人提供虚拟通信网络服务(网络功能虚拟化)和虚拟运营服务。     

一种基础设施云系统——YUN

文章设计了一个虚拟化平台层——YUN系统,介绍了YUN系统的设计目标、系统架构及主要子系统的功能。YUN系统是一种基础设施云系统。YUN系统管理和虚拟化异构、分布的物理资源(包括服务器设备、网络设备、存储设备),并以即付即用的方式将这些资源按需提供给用户使用;通过虚拟化和网络技术,将操作系统功能边界扩展到网络侧,使得终端侧和网络侧能够在一个统一的架构内进行计算和资源的配置、调度、管理,实现网络化操作系统充分、合理地使用和共享网络系统内的资源。     

支持未来网络创新的可编程虚拟化路由器技术

未来互联网体系结构、协议、算法需要在试验网络中进行评估与验证。可编程虚拟化路由器是构建未来互联网试验床的核心设备。由可编程虚拟化路由器构建的试验床可以在一个物理网络上构建多个独立虚拟网络,实现不同体系结构并行实验验证。相比传统路由器,可编程虚拟化路由器需要具备虚拟化与灵活可编程的特点。文章给出一种支持未来网络创新的可编程虚拟化路由器平台——PEARL。PEARL具有可编程、虚拟化隔离与高性能的特点,可满足未来互联网试验床建设要求。     

测试虚拟网络：您准备好了吗

新一代数据中心建设和云计算是目前通信行业最热的技术,不论是各大设备厂商/软件厂商还是运营商都在对这一改变世界的技术进行深入的研究。这类技术无一例外地提到了＂虚拟化＂这个概念,虚拟化开始无处不在,虚拟设备、虚拟计算、虚拟应用还有虚拟化的网络。日益更新的虚拟化技术需要一种全新的测试方案去验证。而这种验证的方案是完全依照虚拟化网络的需求提出的,可以解决客户面对虚拟化时的茫然,提高客户对新技术全面掌控和选择能力,为客户部署新技术提供有力支撑。思博伦通信秦培荣所撰《测试虚拟网络：您准备好了吗》一文详细介绍了思博伦虚拟化网络测试解决方案——Spirent TestCenterTM Virtual。此解决方案基于业界领先的Spirent TestCenter平台上开发的第一个单一应用来验证虚拟网络架构性能、扩展和安全的测试解决方案,可供业内人士参考及应用。     

红帽：开放云平台，不以技术锁定用户

虚拟化作为云计算的核心技术,无论在服务器、网络还是存储方面都发挥了重要作用——将传统的静态物理资源转化为动态资源。红帽作为开源软件和产品以及提供全球性服务的主导开发商和提供者,很早就涉足IT虚拟化技术,于2007年正式发布了RHEV5,以及相关的管理平台,并在服务器虚拟化和网络存储虚拟化方面做了大量开源的工作。     

面向差异化业务请求的虚拟网络映射算法

网络虚拟化是克服当前网络僵化的重要方法,而资源分配是网络虚拟化实现的核心.为了解决业务差异性需求导致的物理网络资源分布不均,造成虚拟网络接受率下降的问题,提出面向差异化业务请求的虚拟网络映射算法.该算法首先定义反应节点和所连接链路资源比的节点饱和度,依此将虚拟节点映射在节点饱和度最接近虚拟网络请求的物理节点上,最后基于所映射的物理节点和节点饱和度约束,将虚拟链路映射在由物理链路组成的路径上.仿真结果表明该算法能够满足不同业务的差异化请求,具有较高的资源利用率和虚拟网络接受率.     

NFCloud:基于OpenContrail的NFV实践

网络功能虚拟化在云计算、虚拟化和SDN技术上运行虚拟的网络功能。对于数通领域的NFV平台,要能为物理网络提供多租户的服务,服务包括服务链和云主机两种模式。文章介绍的NFCloud,是在Opencontrail上进行扩充和改进的NFV平台,具有良好的适用性;并详细分析了NFCloud平台为应对服务提供商要求的高性能和高可用所面临的挑战和解决方法。     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first     

JOURNAL OF ELECTRONICS(CHINA)

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NEXT GENERATION WIRELESS NETWORKS–ESPECIALLY THE USE OF MILLI-MICROWAVE BANDS

The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave （ram-wave） frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.