入侵检测系统IDS在网络安全中的具体应用

当今信息化时代,计算机网络技术在经济、社会、政治、军事、教育等诸多领域得到普遍应用,与此同时,网络安全问题也成为众多专家、学者关注的热点问题。入侵检测系统IDS在网络安全中的具体应用尤为重要,本文以入侵检测系统IDS在网络安全中的具体应用为切入点,首先分析了入侵检测以及入侵检测系统内涵,接着介绍入侵检测系统主要构成,对三种常见的入侵检测方法做了细致的阐述。     

3网络安全技术的发展趋势

防火墙、入侵检测系统是两个当今应用最为广泛的网络安全产品,文章通过介绍防火墙的模式转变、功能扩展、性能提高等一些基本层面的问题和入侵检测技术中的入侵检测系统（IDS）、入侵防御系统（IPS）的应用,论述了网络安全技术的发展趋势。     

网络安全技术的发展趋势

防火墙、入侵检测系统是两个当今应用最为广泛的网络安全产品,文章通过介绍防火墙的模式转变、功能扩展、性能提高等一些基本层面的问题和入侵检测技术中的入侵检测系统(IDS)、入侵防御系统(IPS)的应用,论述了网络安全技术的发展趋势.     

基于环境模拟的入侵检测系统测试方法

入侵检测系(IDS)已经成为保障网络安全不可缺少的环节,对IDS的评估和测试是验证IDS系统有效性的必要手段.讨论了入侵检测系统测试的目的和测试的性能指标,基于对现实网络环境的模拟,建立测试环境,并在此测试环境中搭建软件测试平台,阐述了对入侵检测系统进行测试的方法,最后结合实验给出了仿真测试的结果.     

为用户打造固若金汤的网络安全系统

凭借着对网络安全行业的深刻理解．曙光公司推出了曙光GodEye—HIDS主机入侵检测系统。根据采集数据源的不同，IDS可分为主机型IDS(Host—based IDS)和网络型IDS(Network-based IDS)两种。IDS作为主机型IDS产品．由于部署在被保护的主机上，所以它具备了其它安全措施所无法比拟的先天优势，HIDS从主机／服务器上采集数据．包括操作系统日志、系统进程，件访问和注册表访问等信息；NIDS则是直接从网络中采集原始的数据包，进行检测。HIDS的检测引擎称为“主机代理”；NIDS的检测引擎称为     

一种针对应用程序的嵌入式入侵检测系统

IDS(IntrusionDetectionSystem)是当前网络安全研究的热点。首先比较了当前各类IDS的优缺点,然后重点分析了针对应用程序的IDS,并给出了一种针对应用程序的嵌入式入侵检测系统的模型和实现方法。     

黑客攻击行为分析与网络安全管理平台的系统组成

介绍了黑客攻击的主要方式,提出了应急响应的对策,重点论述了入侵检测系统（IDS）和计算机取证技术,并对网络安全管理平台的构建和系统组成提出了自己的思路。     

入侵检测系统与标准化

入侵检测技术是网络安全的主要技术之一。本文阐述了入侵检测系统(IDS)的基本方法和分类,介绍了当前国内外入侵检测系统的标准化工作进展情况,最后展望了IDS标准化发展的方向。     

入侵检测系统(IDS)的发展

入侵检测系统(IDS)是一种不同于防火墙的主动保护网络资源的网络安全系统,是防范网络攻击的最后一道防线,是其它安全措施的必要补充,在网络安全技术中起不可替代的作用。本文首先给出了入侵检测的概念,并从两个角度对IDS进行了分类,指出了评估IDS的主要性能指标,接着介绍了IDS的发展过程,之后分析了IDS的研究状况和研究热点以及目前的IDS存在的问题,最后展望了IDS发展的方向。     

入侵检测系统的标准化

入侵检测系统(IDS)的标准化是必然要经历的阶段,标准化的制定有利于不同的IDS之间的协作,从而发现新的入侵活动;有利于IDS与访问控制、应急、入侵追踪等系统交换信息,相互协作,形成一个整体有效的安全保障系统.本文首先介绍了网络安全的重要性,并给出了防火墙和入侵检测系统的相关知识,指出了其中存在的问题,从而说明了入侵检测系统标准化产生的背景,接着介绍了国外已经存在的标准草案,之后着重分析了制定IDS标准的意义以及国内制定标准的可行性,最后展望了IDS标准化发展的方向.     

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.