一种可信计算环境下DAA协议实现方案

证明是可信计算从体系结构上保障网络服务安全的重要功能。文中介绍了TCG可信计算环境下的认证策略和以TPM为基础的直接匿名认证协议（Direct Anonymous Attestation,DAA）,分析了其特点,提出为了获得更好的应用性,对DAA协议进行基于ECC算法的扩展方案。经安全性分析证明,该方案在可信计算环境下只需有限的系统资源,可以有效提高可信网络接入的安全性与可管可控性。     

一种有效的WLAN可信匿名认证协议

选取扩展认证-安全传输层(EAP-TLS,Extensible Authentication Protocol-transport Layer Security)协议与直接匿名认证(DAA,Direct Anonymous Attestation)结合,简化了EAP-TLS中用户与服务器间相互证书的交换和认证,去掉冗余步骤,合并EAP-TLS中握手过程和DAA中匿名认证过程。将可信平台模块(TPM,Trusted Platform Module)引入无线局域网(WLAN,Wireless Local Area Networks),实现用户身份的匿名认证,减轻了EAP-TLS协议证书管理压力,不存在效率瓶颈,安全程度比EAP-TLS有所提高,能有效抵抗重放攻击、中间人攻击、拒绝服务(DoS,Denial of Services)攻击等安全威胁。     

基于TPM的Needham-Schroeder协议

论文针对Needham—Schroeder对称密钥协议存在的问题,提出了在参与协议运行的各个实体中嵌入可信平台模块TPM,利用TPM的保护存储等功能,实现对各个实体的本地保护;利用TPM的平台证实功能使得认证服务器与实体A、实体A与实体B在协议的运行中分别进行双向证实;由此对协议进行改进,增强了协议运行的安全性。     

基于椭圆曲线的隐私增强认证密钥协商协议

认证密钥协商协议能够为不安全网络中的通信双方提供安全的会话密钥,但是,大多数的认证密钥协商协议并没有考虑保护用户隐私.论文关注网络服务中用户的隐私属性,特别是匿名性和可否认性,规范了增强用户隐私的认证密钥协商协议应满足的安全需求,即双向认证、密钥控制、密钥确认、会话密钥保密、已知会话密钥安全、会话密钥前向安全、用户身份匿名、用户身份前向匿名、不可关联和可否认,并基于椭圆曲线密码系统设计了一个满足安全需求的隐私增强认证密钥协商协议.     

基于车载自组网的匿名认证机制

车载自组网中,车辆在进行相互通信时需要对收到的信息进行合法性验证,但同时又不希望自己的身份被泄露,从而导致了安全与隐私保护之间的问题。匿名认证是车载自组网中安全和身份隐私保护的关键机制,本文对现有的匿名认证方案进行了分类对比,分析了各个方案的优缺点。     

改进的移动计算平台直接匿名证明方案

分析了Ge等人提出的直接匿名证明方案的安全缺陷,指出该方案的认证协议在用于远程证明时不能抵抗重放攻击和平台伪装攻击。提出一种改进的直接匿名证明的认证协议,引入会话密钥协商机制,增强互认证功能。分析表明,改进方案在正确进行直接匿名证明的前提下,满足不可伪造性和匿名性,能够抵抗重放攻击和平台伪装攻击,协议性能满足移动计算平台的可信验证需求。     

面向轻量级物联网设备的高效匿名身份认证协议设计

针对现有方案中复杂安全原语不适合资源受限的物联网设备的问题,基于物理不可克隆函数（PUF）为物联网设备设计了一种轻量级高效匿名身份认证协议。通过形式化安全模型和ProVerif协议分析工具,证明该协议满足信息传输机密性、完整性、不可追踪和前向/后向保密等13种安全属性。与近几年认证方案的性能对比分析表明,该协议在设备端与服务器端的计算开销分别为0.468 ms和0.072 ms,设备存储开销与通信开销分别为256 bit和896 bit,高度适用于资源受限的轻量级物联网设备。     

一种具有阅读器匿名功能的射频识别认证协议

在射频识别(RFID)的应用中,安全问题特别是用户隐私问题正日益凸显。因此,(用户)标签信息的隐私保护的需求越来越迫切。在RFID系统中,标签的隐私保护不仅是对外部攻击者,也应该包括阅读器。而现有许多文献提出的认证协议的安全仅针对外部攻击者,甚至在外部攻击者的不同攻击方法下也并不能完全保证安全。该文提出两个标签对阅读器匿名的认证协议:列表式RFID认证协议和密钥更新式RFID认证协议。这两个协议保证了阅读器对标签认证时,标签的信息不仅对外部攻击者是安全的而且对阅读器也保持匿名和不可追踪。相较于Armknecht等人提出的对阅读器匿名和不可追踪的认证协议,该文所提的协议不再需要增加第三方帮助来完成认证。并且密钥更新式RFID匿名认证协议还保证了撤销后的标签对阅读器也是匿名性和不可追踪的。     

智能车载自组织网络中匿名在线注册与安全认证协议

随着智能交通系统(ITS)的建立,车载自组织网络(VANETs)在提高交通安全和效率方面发挥着重要的作用。由于车载自组织网络具有开放性和脆弱性特点,容易遭受各种安全威胁与攻击,这将阻碍其广泛应用。针对当前车载自组织网络传输中数据的认证性与完整性,以及车辆身份的隐私保护需求,该文提出一种智能车载自组织网络中的匿名在线注册与安全认证协议。协议让智能车辆在公开信道以匿名的方式向交通系统可信中心(TA)在线注册。可信中心证实智能车辆的真实身份后,无需搭建安全信道,在开放网络中颁发用于安全认证的签名私钥。车辆可以匿名发送实时交通信息到附近路边基站单元(RSU),并得到有效认证与完整性检测。该协议使得可信中心可以有效追踪因发送伪造信息引起交通事故的匿名车辆。协议可以让路边基站单元同时对多个匿名车辆发送的交通信息进行批量认证。该协议做了详细的安全性分析和性能分析。性能比较结果表明,该协议在智能车辆端的计算开销以及在路边基站单元端的通信开销都具有明显优势,而且无需搭建安全信道就能够实现匿名在线注册,因此可以安全高效地部署在智能车载自组织网络环境。     

基于属性的k次匿名大数据中心访问控制方案

在研究信息服务中心云存储用户的隐私保护问题时,基于属性的加密方案是一种前景看好的解决途径,它有效满足了匿名访问和数据加密等要求。然而,基于属性的加密方案只适用于对云存储服务中加密数据的认证访问。在云计算服务访问控制的环境中,部署这一方案是不切实际的。文章研究大数据中心云存储匿名访问控制的安全需求,介绍基于属性的访问控制方案构成,设计基于属性的k次匿名访问控制安全模型,描述方案的基本原理,给出方案的工作流程,并对方案的安全性和效率进行分析。     

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.