中国联通下一代网络的实践与思考

文章介绍了中国联通的多业务统一网络平台,包括多业务服务质量(QoS)保障的融合的承载平台、融合的软交换核心控制架构、多业务QoS保障的城域综合业务网络和基于IPv6的网络承载技术.依据中国联通在下一代网络(NGN)方面的实践,文章对多业务统一网络平台的先进性、效果与效益进行了总结,并指出了存在的问题.文章指出:由于未来NGN技术将向基于IP多媒体子系统(IMS)的NGN方向继续演进,同时网络承载层技术将逐步从IPv4过渡到IPv6,因此中国联通将积极探索基于IMS的NGN网络架构与组网模式,努力开展面向IPv6的应用实验与推广工作,特别是移动IPv6业务的开发和推进.     

下一代网络的发展及其与IPv6的关系

下一代网络NGN是当今的研究热点，而作为与NGN发展密切相关的IPv6，将来必将取代IPv4。从NGN的概念出发，着重介绍了下一代网络（NGN）的网络结构、特点以及现阶段发展状况和今后发展趋势，并对NGN与IPv6的关系以及IPv6在NGN中应用的场景进行了详细的探讨。     

下一代网络（NGN）的发展及其与IPv6的关系

下一代网络NGN是当今的研究热点，而作为与NGN发展密切相关的IPv6，将采必将取代IPv4。从NGN的概念出发，着重介绍了下一代网络（NGN）的网络结构、特点以厦现阶段发展状况和今后发展趋势，并对NGN与Ipv6的关系以及IPv6在NGN中应用的场景进行了详细的探讨。     

ITU-TNGN和IPv6标准化、产业发展和可能的过渡方式

随着新业务和应用的出现,NGN和IPv6技术的发展和应用日益成为业界关注的焦点。本文对ITU-T NGN和IPv6的技术现状、标准化和产业化发展情况作了一个简单的介绍。文章还阐述了由IPv4网络向IPv6网络过渡的三种方式和运营商的可能选择。最后,文章对中国的以IPv6为基础的下一代互联网的发展进行了展望。     

IPv6测试研究与实践

从IPv6协议测试范围和测试方法两个方面对IPv6协议测试进行了研究分析,并从设备、网络和网站系统等3个方面探讨论了IPv6测试的规范和体系.基于近年IPv6测试领域相关成果,介绍了IPv6论坛的测试体系IPv6 Ready和IPv6 Enabled,以及全球在IPv6测试方面的实践和探索.     

承载网路由器IPv6测试分析

从IPv6测试内容入手,介绍了承载网路由器IM入网检测和运营商测试的情况,并提出了3个未来IPv6测试的关注点.     

下一代核心网络体系结构的分析与研究

作为真正完整的下一代网络解决方案,开放式、层次化结构的分组交换网络将成为NGN的承载各种业务的核心网络,IP协议将最终演化成为NⅡ和GⅡ的核心。下一代网的核心体系将是基于IPv6的骨干核心网络,能够在保持IP协议的简单性和自由性的同时提供综合的业务和QoS保障。但是,从IPv4到IPv6的过渡是一个非常复杂的过程,在向NGN理想网络模型的演进过程中,基于MPLS的IP核心网演进方案可用于运营级的大型IP骨干网络中,能够在骨干网络升级的同时建立IPv6核心的标签交换网络,是一种重要的NGN网络演进方案。     

NGN的IP承载方案

NGN是完全基于数据网络、特别是分组网络（IP网络）的IP承载网来实现语音业务及其他增值业务的开放平台.分析了NGN基于IP的承载方案：NGN对承载网的要求、NGN的承载方式、QoS保证及国内的著名应用介绍等.     

国内外NGN发展动向

业界对下一代网络（NGN）的概念持有不同的观点。根据国际上有关NGN的研究与行动，NGN包含以智能光网为核心的下一代光网络，以MPLS和IPv6为重点的下一代IP网络以及采用3G，4G的下一代无线通信网络等，在众多的NGN计划中，欧盟的NGN行动计划较为突出。首先对其使命、研究内容等进行了整体的介绍，在介绍了中国有关NGN的研究后，就NGN的网络功能结构如何以及美国有关建设下一代电话网的举措进行了阐述。最后对中国NGN的发展提出了殷切希望。     

IPv6在3G中的应用

随着IPv6标准的成熟和第三代移动通信(3G)的发展,在3G中承载数据业务的IP承载网采用IPv6将是必然的发展趋势.文章首先介绍了IPv6相对于IPv4的一些新特点,同时介绍了3G的体系结构,然后对IPv6的这些新特点在3G中应用的进行分析.最后总结了IPv6对3G发展的影响.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

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.     

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.     

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.     

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.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.