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1.
针对传统跨域密钥协商协议安全性不足问题,提出一种新的跨域量子密钥协商协议。在无证书密钥协商体系下,采用量子密钥协商与经典密码算法结合的方案,提高了协议适应现有通信网络架构的能力。密钥协商过程使用三粒子量子隐形传态,利用量子态不可克隆定理保障协商过程中密钥的安全性。与其他方案相比,本协议具有较高的量子比特效率,并且可以抵抗中间人攻击、重放攻击等多种内部和外部攻击手段。  相似文献   

2.
目前大部分基于身份的三方认证密钥协商协议都存在安全缺陷,文中在Xu等人提出的加密方案的基础上,设计了一种基于身份的三方认证密钥协商协议.该协议的安全性建立在BDDH假设基础上,经安全性分析,协议具有已知密钥安全,PKG前向安全,并能抵抗未知密钥共享攻击和密钥泄露伪装攻击,因此该协议是一个安全的三方密钥协商协议.  相似文献   

3.
现已存在的签名方案,大都是基于证书的密码体制或基于身份的密码体制提出的,不可避免的会存在证书的管理问题或密钥托管问题。基于无证书公钥密码体制的优点,结合申军伟等人的无证书代理签名方案,提出了一个基于无证书的具有指定验证者的代理签名方案。该方案除了能够避免密钥托管问题,能够抵制替换公钥攻击和KGC密钥攻击外,相比原方案还具有指定验证的特点,从而可以满足代理签名的一切性质,提高了安全性。  相似文献   

4.
认证协议的设计是目前车载自组网(VANET)安全领域的研究热点。现有的认证方案中普遍存在密钥托管带来的安全问题,以及使用计算量大的双线性对导致认证效率很低。针对以上问题,该文提出可证明安全的无证书批认证方案,方案中车辆的密钥由车辆自身和一个密钥生成中心共同生成,解决密钥需要托管给第三方维护的问题;方案的签名构造不使用计算量大的对运算,减少了计算开销;引入批认证来减少路边设施的认证负担,提高认证效率。基于求解椭圆曲线上的离散对数问题的困难性假设,在随机预言机模型中证明了该方案可以抵抗自适应选择消息和身份攻击,从而抵抗更改攻击和假冒攻击,并具有匿名性、可追踪性等特点。与现有方案相比,该方案实现了更高效的认证。  相似文献   

5.
《现代电子技术》2017,(13):87-90
主要研究随机密钥协商问题,针对Diffie-Hellman协议、SAKA协议和改进Lin协议、E-SAKA协议等存在的不具有认证功能和不能抵抗中间人攻击等缺陷,应用动态双向认证因子认证方法和非时间同步技术提出一种随机密钥协商协议,该协议适用于OTP动态口令系统设计,同时解决密钥协商过程中的动态认证和时间同步问题。最后,在标准模型下证明了方案的安全性。  相似文献   

6.
文章利用椭圆曲线上双线性映射的特性,分别提出了基于身份的双方密钥协商方案和三方密钥协商方案。通过较少的步骤,同时实现密钥协商和用户相互认证,其代价低于使用证书的密钥协商方案。文章最后对方案的正确性、安全性进行了简单分析。  相似文献   

7.
郑明辉  崔国华  祝建华 《电子学报》2008,36(7):1368-1372
 一个非认证的多方密钥协商协议不能对通信参与方和消息进行认证,它必须依赖认证的网络信道或其他的认证方法.分析了Horng在认证广播信道下提出的高效多方密钥协商协议,指出它不能抵抗内部恶意参与方发起的密钥协商阻断攻击,该攻击导致通信的其他诚实参与方不能正确计算出相同的共享密钥.提出了一种安全的多方密钥协商协议,在Horng协议中加入了消息正确性的认证方法,能够检测出组内恶意参与方,并在随机预言模型下证明了提出的协议能够抵抗密钥协商阻断攻击.  相似文献   

8.
分析了Kim等人提出的不依赖于双线性对运算的无证书两方认证密钥协商协议,指出该协议在公钥替换攻击下不满足基本伪装攻击安全性,并给出了一个具体攻击。针对该协议存在的安全性缺陷,提出了一个改进的无证书两方认证密钥协商协议。分析表明,所提出的改进协议能够有效地抵抗公钥替换攻击并满足一些必要的安全属性。  相似文献   

9.
罗东俊 《信息技术》2006,30(5):159-161
针对Diffie-Hellman密钥协商协议易受中间人(man in the middle)攻击的问题,提出了一种自证明身份的密钥协商协议,阐述了密钥交换原理,分析了其安全性和实现的关键技术。该协议将RSA与离散对数相结合,使通信双方在不需对方公开密钥证书,不需数字签名,也不需密钥分配中心(KDC)的条件下进行双向身份认证,并同时产生共享的会话密钥,具有一定实用价值。  相似文献   

10.
在无证书公钥密码体制下对一种多方可认证密钥协商方案进行了分析,指出该方案无法抵抗合法用户的扮演攻击和口令偶尔泄露导致的危机。分析了该方案存在漏洞的原因,并在此基础上给出一个改进的密钥协商方案。新方案引入密钥种子和口令进化机制解决了上述问题,同时消除了冗余消息,降低了用户占用的带宽。分析表明新方案的安全性更强。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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