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排序方式: 共有6815条查询结果,搜索用时 9 毫秒
941.
942.
Verification of Authentication Protocols for Epistemic Goals via SAT Compilation 总被引:1,自引:0,他引:1 下载免费PDF全文
Kai-Le Su Qing-Liang Chen Abdul Sattar Wei-Ya Yue Guan-Feng Lv and Xi-Zhong Zheng 《计算机科学技术学报》2006,21(6):932-943
This paper introduces a new methodology for epistemic logic, to analyze communication protocols that uses knowledge structures, a specific form of Kripke semantics over hostile networks. The paper particularly focuses on automatic verification of authentication protocols. Our approach is based on the actual definitions of a protocol, not on some difficultto-establish justifications. The proposed methodology is different from many previous approaches to automatic verification of security protocols in that it is justification-oriented instead of falsification-oriented, i.e., finding bugs in a protocol. The main idea is based on observations: separating a principal executing a run of protocol from the role in the protocol, and inferring a principal's knowledge from the local observations of the principal. And we show analytically and empirically that this model can be easily reduced to Satisfiability (SAT) problem and efficiently implemented by a modern SAT solver. 相似文献
943.
研究了视频误码的语法/语义检测、相关性检测方法和错误掩盖方法,分析了AVS的技术特性。在此基础上提出了一种基于AVS的错误两步检测法和基于图像编码帧类型(I,P,B)的自适应错误掩盖方法。实验结果表明,两步检测法能对AVS码流中的错误进行准确定位,自适应错误掩盖方法对图像的恢复效果显著。同时该方法不中断解码器,不影响解码器的实时解码速度。 相似文献
944.
945.
Minjie Xie 《中兴通讯技术(英文版)》2012,(2):25-33
Lattice vector quantization(LVQ) has been used for real-time speech and audio coding systems.Compared with conventional vector quantization,LVQ has two main advantages:It has a simple and fast encoding process,and it significantly reduces the amount of memory required.Therefore,LVQ is suitable for use in low-complexity speech and audio coding.In this paper,we describe the basic concepts of LVQ and its advantages over conventional vector quantization.We also describe some LVQ techniques that have been used in speech and audio coding standards of international standards developing organizations(SDOs). 相似文献
946.
从目前企业的安全体系和安全策略出发,本文设计了一套适用于目前多种企业应用的统一认证系统,使用LDAP标准协议管理用户信息,实现了统一管理、统一授权;采用了双因素认证服务器作为认证引擎,加强了身份认证的强度。 相似文献
947.
948.
Untraceable electronic cash is an attractive payment tool for electronic-commerce because its anonymity property can ensure the privacy of payers. However, this anonymity property is easily abused by criminals. In this paper, several recent untraceable e-cash systems are examined. Most of these provide identity revealing only when the e-cash is double spent. Only two of these systems can disclose the identity whenever there is a need, and only these two systems can prevent crime. We propose a novel e-cash system based on identity-based bilinear pairing to create an anonymity revocation function. We construct an identity-based blind signature scheme, in which a bank can blindly sign on a message containing a trustee-approved token that includes the user’s identity. On demand, the trustee can disclose the identity for e-cash using only one symmetric operation. Our scheme is the first attempt to incorporate mutual authentication and key agreement into e-cash protocols. This allows the proposed system to attain improvement in communication efficiency when compared to previous works. 相似文献
949.
Wireless sensor networks (WSNs) are vulnerable to security attacks due to their deployment and resource constraints.Considering that most large-scale WSNs follow a two-tiered architecture,we propose an... 相似文献
950.
Recently, several studies addressed security and privacy issues in vehicular ad hoc networks (VANETs). Most of them focused on safety applications. As VANETs will be available widely, it is anticipated that Internet services could be accessed through VANETs in the near future. Thus, non-safety applications for VANETs would rise in popularity. This paper proposes a novel portable privacy-preserving authentication and access control protocol, named PAACP, for non-safety applications in VANETs. In addition to the essential support of authentication, key establishment, and privacy preservation, PAACP is developed to provide sophisticated differentiated service access control, which will facilitate the deployment of a variety of non-safety applications. Besides, the portability feature of PAACP can eliminate the backend communications with service providers. Therefore, better performance and scalability can be achieved in PAACP. 相似文献