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81.
《Information Security Journal: A Global Perspective》2013,22(4):182-190
ABSTRACT A password-based authentication is still the most prevalent authentication method because of its convenience and easy implementations. Since a password is transmitted via network, it has an inherent vulnerability of password exposure to an attacker. A one-time password system reduces the risk of a security breach even when a password is exposed to an attacker, because the password is only meaningful at a given time. A grid data security system uses a technology, GridOne?, which allows the use of a one-time password without requiring preinstalled hardware or software infrastructures, and it provides strong security over conventional password-based authentication systems. We analyzed the weakness of the grid data security authentication system and provide a suggestion to compensate for its vulnerability. 相似文献
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《Information Security Journal: A Global Perspective》2013,22(5):248-256
ABSTRACT A mobile ad-hoc network (MANET) is an autonomous system of mobile nodes connected by wireless links in which nodes cooperate by forwarding packets for each other thereby enabling communication beyond direct wireless transmission range. Example applications include battlefield communication, disaster recovery operations, and mobile conferencing. The dynamic nature of ad-hoc networks makes them more vulnerable to security attacks compared with fixed networks. Providing security in mobile ad-hoc networks has been a major issue in recent years. Most of the secure routing protocols proposed by researchers need a centralized authority or a trusted third party to provide authentication. This destroys the self-organizing nature of ad-hoc networks. Black Hole attack is one of the routing attacks that occur in MANETs. In this attack, a malicious node uses the routing protocol to advertise itself as having the shortest path to the node whose packets it wants to intercept. In this article, we propose an enhanced certificate based authentication mechanism, where nodes authenticate each other by issuing certificates to neighboring nodes and generating public key without the need of any online centralized authority. The proposed scheme uses Multicast Ad-hoc On Demand Distance Vector Routing (MAODV) protocol as a support for certification. The effectiveness of our mechanism is illustrated by simulations conducted using network simulator ns-2. 相似文献
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Toxic and Potent Chinese Materia Medica (T/PCMM) is a special and very important category of Chinese medicines. They have long been used in traditional medical practice and are being used more and more widely throughout the world in recent years. As there may be many fatal toxic effects caused by misusing or confusion of T/PCMM, their quality and safety control arouse increasing attention internationally. Researches on the accurate identification to ensure the safe use of T/PCMM are acquired; however, there are few reports on authentication. We are carrying out a series of studies on 31 T/PCMM originating from plants, animals, minerals, and secreta. In our previous studies, we proved that modern microscopic authentication is a simple, fast, effective, low cost, and less toxic method for identifying animal, seed, and flower T/PCMM. In the present study, we focused on the authentication of four kinds of mineral arsenicals, including orpiment (mainly containing As2S3), realgar (mainly containing As4S4), arsenolite, and arsenic trioxide (mainly containing As2O3). We examined the macroscopic and microscopic characteristics of the above minerals and found that they all can be easily identified and authenticated by using light microscopy coupled with polarized microscopy. Moreover, the authentication results for arsenolite and arsenic trioxide are confirmed by ICP‐MS analysis. We are sure that the morphological and microscopic characteristics indicated here are indispensable to establishing standards for these four mineral T/PCMMs. Microsc. Res. Tech. 74:1‐8, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
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通用移动通信系统采用3GPP认证与密钥协商协议作为其安全框架,该协议对GSM存在的安全隐患作了有效的改进.对3GPP认证与密钥协商协议进行安全性研究,分析其容易遭受4种类型攻击方式.为了解决上述存在的安全隐患,提出在位置更新与位置不变两种情况下的基于公钥密码学的认证与密钥协商协议,采用形式化的分析方式证明了所提出算法的安全性,并将该协议与已有协议在安全性方面进行了比较.结果显示,所提出的协议算法能够极大地增强3GPP认证与密钥协商协议的安全性. 相似文献
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基于口令的远程身份认证协议是目前认证协议研究的热点。2005年,Sung-Woon Lee等人提出了一个低开销的基于随机数的远程身份认证协议即Lee-Kim-Yoo协议,首先分析了此协议中所存在的安全性缺陷,随后构造了一个基于随机数和Hash函数,并使用智能卡的远程身份认证协议,最后用BAN逻辑对修改后的协议进行了形式化的分析,结果表明修改后的协议能够达到协议的安全目标。 相似文献
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提出一种基于H.264视频内容认证的半脆弱水印,该水印方案对视频内容恶意篡改敏感,而对于视频重编码等内容保持操作鲁棒。水印方案建立在视频压缩域上利用图像块之间不变的能量关系构建基于内容的特征码。由于DCT系数块能量主要集中在低频部分,所以用低频部分来生成特征码,用高频部分来嵌入水印。实验结果证明算法是有效的,并且较好地实现了篡改定位。 相似文献
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为了解决学生管理系统的安全性和效率问题,分析了已有系统的不足,提出了一个安全高效的学生综合管理系统的解决方案。该方案利用C/S结构安全中间件,进行SQL Server 2000安全设置弥补TDS(TabularData Stream)协议漏洞、与已有数据库系统数据共享等方法,保证了管理系统的可用性和有效性,克服了已有系统存在的安全性不高、效率低下的不足。基于PowerBuilder的前端和SQL SERVER 2000的后台的系统运行结果表明,该方案可行有效。 相似文献