Secure Multi-party Computation has been a research focus in international cryptographic community in recent years. In this paper the authors investigate how some computational geometric problems could be solved in a c...Secure Multi-party Computation has been a research focus in international cryptographic community in recent years. In this paper the authors investigate how some computational geometric problems could be solved in a cooperative environment, where two parties need to solve a geometric problem based on their joint data, but neither wants to disclose its private data to the other party. These problems are the distance between two private points, the relation between a private point and a circle area, the relation between a private point and an ellipse area and the shortest distance between two point sets. The paper gives solutions to these specific geometric. problems, and in doing so a building block is developed, the protocol for the distance between two private points, that is also useful in the solutions to other geometric problems and combinatorial problems.展开更多
隐私保护集合交集(private set intersection,PSI)计算属于安全多方计算领域的特定应用问题,不仅具有重要的理论意义也具有很强的应用背景,在大数据时代,对该问题的研究更是符合人们日益强烈的在享受各种服务的同时达到隐私保护的需求....隐私保护集合交集(private set intersection,PSI)计算属于安全多方计算领域的特定应用问题,不仅具有重要的理论意义也具有很强的应用背景,在大数据时代,对该问题的研究更是符合人们日益强烈的在享受各种服务的同时达到隐私保护的需求.对安全多方计算基础理论进行了简要介绍,并重点介绍了目前主流的安全多方计算框架下2类PSI研究技术:传统的基于公钥加密机制,混乱电路,不经意传输的PSI协议和新型的云辅助的PSI协议,并对各类协议的过程、适用性、复杂性进行简要分析总结.同时,也对隐私保护集合交集问题的应用场景进行详细说明,进一步体现对该问题的实际研究价值.随着对该问题的不断深入研究,目前已经设计了在半诚实模型下快速完成上亿元素规模的隐私集合求交集协议.展开更多
随着物联网和大数据技术的发展,在计算机和手机上出现了大量分布式应用程序.然而现有的分布式数据处理方式已不能很好地满足用户对隐私保护的需求.隐私集合交集(private set intersection,PSI)协议作为一项典型的面向隐私保护的分布式...随着物联网和大数据技术的发展,在计算机和手机上出现了大量分布式应用程序.然而现有的分布式数据处理方式已不能很好地满足用户对隐私保护的需求.隐私集合交集(private set intersection,PSI)协议作为一项典型的面向隐私保护的分布式集合计算技术,允许各参与方输入其私有集合,共同计算集合的交集,且不泄露除交集以外的任何信息.PSI协议作为安全多方计算的一种重要应用,已被广泛应用于隐私计算领域,具有重要的理论和实践意义.首先介绍PSI协议的基本密码技术、敌手模型、安全证明、编程框架等基础知识;其次系统总结了构造传统PSI协议的设计框架:基于公钥加密体制的框架、基于混淆电路的框架、基于不经意传输的框架;随后介绍PSI协议核心的隐私集合元素比较技术工具:不经意伪随机函数、不经意多项式评估、布隆过滤器等;进一步地详细阐述了适应新型应用场景的PSI方案:基于云辅助的PSI、非平衡型PSI、基于阈值的PSI和多方PSI;最后总结并展望面向隐私保护的集合交集计算中亟待解决问题和发展方向.展开更多
The problem of two-party oblivious polynomial evaluation (OPE) is studied, where one party (Alice) has a polynomial P(x) and the other party (Bob) with an input x wants to learn P(x) in such an oblivious way that Bob ...The problem of two-party oblivious polynomial evaluation (OPE) is studied, where one party (Alice) has a polynomial P(x) and the other party (Bob) with an input x wants to learn P(x) in such an oblivious way that Bob obtains P(x) without learning any additional information about P except what is implied by P(x) and Alice does not know Bob's input x. The former OPE protocols are based on an intractability assumption except for OT protocols. In fact, evaluating P(x) is equivalent to computing the product of the coefficient vectors (a(0),...,a(n)) and (1,...,x(n)). Using this idea, an efficient scale product protocol of two vectors is proposed first and then two OPE protocols are presented which do not need any other cryptographic assumption except for OT protocol. Compared with the existing OPE protocol, another characteristic of the proposed protocols is the degree of the polynomial is private. Another OPE protocol works in case of existence of untrusted third party. Keywords oblivious polynomial evaluation, oblivious transfer, secure multi-party computation, information.展开更多
文摘Secure Multi-party Computation has been a research focus in international cryptographic community in recent years. In this paper the authors investigate how some computational geometric problems could be solved in a cooperative environment, where two parties need to solve a geometric problem based on their joint data, but neither wants to disclose its private data to the other party. These problems are the distance between two private points, the relation between a private point and a circle area, the relation between a private point and an ellipse area and the shortest distance between two point sets. The paper gives solutions to these specific geometric. problems, and in doing so a building block is developed, the protocol for the distance between two private points, that is also useful in the solutions to other geometric problems and combinatorial problems.
文摘隐私保护集合交集(private set intersection,PSI)计算属于安全多方计算领域的特定应用问题,不仅具有重要的理论意义也具有很强的应用背景,在大数据时代,对该问题的研究更是符合人们日益强烈的在享受各种服务的同时达到隐私保护的需求.对安全多方计算基础理论进行了简要介绍,并重点介绍了目前主流的安全多方计算框架下2类PSI研究技术:传统的基于公钥加密机制,混乱电路,不经意传输的PSI协议和新型的云辅助的PSI协议,并对各类协议的过程、适用性、复杂性进行简要分析总结.同时,也对隐私保护集合交集问题的应用场景进行详细说明,进一步体现对该问题的实际研究价值.随着对该问题的不断深入研究,目前已经设计了在半诚实模型下快速完成上亿元素规模的隐私集合求交集协议.
文摘随着物联网和大数据技术的发展,在计算机和手机上出现了大量分布式应用程序.然而现有的分布式数据处理方式已不能很好地满足用户对隐私保护的需求.隐私集合交集(private set intersection,PSI)协议作为一项典型的面向隐私保护的分布式集合计算技术,允许各参与方输入其私有集合,共同计算集合的交集,且不泄露除交集以外的任何信息.PSI协议作为安全多方计算的一种重要应用,已被广泛应用于隐私计算领域,具有重要的理论和实践意义.首先介绍PSI协议的基本密码技术、敌手模型、安全证明、编程框架等基础知识;其次系统总结了构造传统PSI协议的设计框架:基于公钥加密体制的框架、基于混淆电路的框架、基于不经意传输的框架;随后介绍PSI协议核心的隐私集合元素比较技术工具:不经意伪随机函数、不经意多项式评估、布隆过滤器等;进一步地详细阐述了适应新型应用场景的PSI方案:基于云辅助的PSI、非平衡型PSI、基于阈值的PSI和多方PSI;最后总结并展望面向隐私保护的集合交集计算中亟待解决问题和发展方向.
文摘The problem of two-party oblivious polynomial evaluation (OPE) is studied, where one party (Alice) has a polynomial P(x) and the other party (Bob) with an input x wants to learn P(x) in such an oblivious way that Bob obtains P(x) without learning any additional information about P except what is implied by P(x) and Alice does not know Bob's input x. The former OPE protocols are based on an intractability assumption except for OT protocols. In fact, evaluating P(x) is equivalent to computing the product of the coefficient vectors (a(0),...,a(n)) and (1,...,x(n)). Using this idea, an efficient scale product protocol of two vectors is proposed first and then two OPE protocols are presented which do not need any other cryptographic assumption except for OT protocol. Compared with the existing OPE protocol, another characteristic of the proposed protocols is the degree of the polynomial is private. Another OPE protocol works in case of existence of untrusted third party. Keywords oblivious polynomial evaluation, oblivious transfer, secure multi-party computation, information.
