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基于虹膜信息的身份签名方案 总被引:3,自引:0,他引:3
生物特征的应用集中在两个方面,一是传统的身份认证和识别技术,二是密钥的产生技术。该文研究了从虹膜信息中提取特征码,采用模糊方法从虹膜特征码中提取随机串并将其嵌入到椭圆曲线中等问题。以虹膜信息为基础产生公钥,提出了一种基于虹膜信息的身份签名方案。该方案引进两个密钥生成系统,可有效防止单个密钥生成系统随意伪造签名的缺陷,进一步提高系统的安全性和可靠性。在随机预言机模型下,该方案被证明在适应性选择消息和身份攻击下具有不可伪造安全,并能有效抵抗生日攻击。 相似文献
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标准模型下的基于身份签名方案大多数是存在性不可伪造的,无法阻止攻击者对已经签名过的消息重新伪造一个合法的签名,并且验证签名需要执行耗时的双线性对运算。为了克服已有基于身份签名方案的安全性依赖强和计算代价大等缺陷,提出了一个强不可伪造的基于身份服务器辅助验证签名方案,并在标准模型下证明了新方案在合谋攻击、自适应选择身份和消息攻击下是安全的。分析结果表明,新方案有效减少了双线性对的计算量,大大降低了签名验证算法的计算复杂度,在效率上优于已有的基于身份签名方案。 相似文献
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现有的广义指定验证者签名方案的安全性大都是在随机预言机模型下证明的,但是在该模型下的可证安全并不意味着在现实中是安全的.基于Zhang等人提出的无随机预言机模型下的短签名方案,提出了一个在标准模型下可证安全的广义指定验证者签名方案,其强不可伪造性基于k+1平方根假设和指数知识假设,证明了提出方案在选择公钥和选择消息攻击下是无条件不可传递的.方案的签名长度为1366 bits,比现有方案的签名长度要短. 相似文献
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Hierarchical identity-based signature(HIBS)has wide applications in the large network. However, the existing works cannot solve the trade-off between the security and efficiency. The main challenge at present is to construct a high efficient and strong secret HIBS with a low computation cost. In this paper, a new construction of HIBS scheme is proposed. The new scheme achieves the adaptive security which is a strong security in the identity-based cryptography. But our scheme has short public parameters and the private keys size shrinks as the hierarchy depth increases. The signature size is a constant and the cost of verification only requires four bilinear pairings, which are independent of hierarchy depth. Furthermore, under the q-strong computational diffie-Hellman problem(q-SDH)assumption, the scheme is provably secure against existential forgery for adaptive chosen message and identity attack in the standard model. 相似文献
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现有会话密钥可托管的ID-AKA(IDentity-based Authenticated Key Agreement)协议要么存在已知安全缺陷,要么是在随机预言模型下可证明安全.基于Boneh等人定义的安全陷门函数,提出一种会话密钥可托管的ID-AKA协议.在ID-BJM模型基础上,扩展定义了ID-AKA协议分析的标准安全模型.扩展模型将安全游戏划分为两个阶段,去除了随机预言机,能完备地模拟不同类型敌手的行为.在扩展模型下,新协议的安全性被规约为多项式时间敌手求解判定性BDH(Bilinear Diffie-Hellman)难题和判定性BDHI(Bilinear Diffie-Hellman Inversion)难题,具有可证明安全性. 相似文献
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异构签密可以保证异构密码系统之间数据的机密性和不可伪造性。该文分析了一个传统公钥密码(PKI)和身份密码(IBC)之间的PKI→IBC和IBC→PKI双向匿名异构签密方案的安全性,指出PKI→IBC方案和IBC→PKI方案均不能抵挡敌手攻击,敌手在获取密文前提下均可解密密文。为了增强安全性,该文提出一个改进的PKI→IBC和IBC→PKI方案,并在随机预言模型下基于计算性Diffie-Hellman困难问题和双线性Diffie-Hellman困难问题证明新方案满足机密性与不可伪造性。同时效率分析表明,所提方案具有更高的通信效率。 相似文献
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In this article, based on Chatterjee-Sarkar' hierarchical identity-based encryption (HIBE), a novel identity-based encryption with wildcards (WIBE) scheme is proposed and is proven secure in the standard model (without random oracle). The proposed scheme is proven to be secure assuming that the decisional Bilinear Diffie-Hellman (DBDH) problem is hard. Compared with the Wa-WIBE scheme that is secure in the standard model, our scheme has shorter common parameters and ciphertext length. 相似文献
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To satisfy the requirements of identity authentication and data possession proven in the cloud application scenarios,a provable data possession scheme with authentication was proposed.Based on data tag signature and randomness reusing,the proposed scheme could accomplish several issues with three interactions,including the possession proof of cloud data,the mutual authentication between user and cloud computing server,the session key agreement and confirmation.Compared to the simple combination of authentication key agreement and provable data possession schemes,the proposed scheme has less computation and interactions,and better provable securities.In the random oracle model,the security proof of the proposed scheme is given under the computational Diffie-Hellman assumption. 相似文献
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We propose and analyze two efficient signature schemes whose security is tightly related to the Diffie-Hellman problems in
the random oracle model. The security of our first scheme relies on the hardness of the computational Diffie-Hellman problem;
the security of our second scheme - which is more efficient than the first-is based on the hardness of the decisional Diffie-Hellman
problem, a stronger assumption. Given the current state of the art, it is as difficult to solve the Diffie-Hellman problems
as it is to solve the discrete logarithm problem in many groups of cryptographic interest. Thus, the signature schemes shown
here can currently offer substantially better efficiency (for a given level of provable security) than existing schemes based
on the discrete logarithm assumption. The techniques we introduce can also be applied in a wide variety of settings to yield
more efficient cryptographic schemes (based on various number-theoretic assumptions) with tight security reductions. 相似文献
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时控性加密(TRE)是一种被称为“向未来发送消息”的密码原语,接收方在未来指定时间之前无法解密密文。目前,大部分TRE方案采用非交互式单时间服务器方法,系统用户能够正常解密,依赖于单一时间服务器在预定解密时间计算并广播的时间陷门。如果单一的时间服务器遭受攻击,或被腐败,则容易直接威胁TRE的安全应用。因此,需要将1个时间服务器“分散”成多个。但已有多时间服务器TRE方案既没有给出安全性分析,也没有给出严格的安全性证明。为此,该文给出一种随机预言机模型下基于双线性迪菲·赫尔曼(BDH)问题的多时间服务器的TRE模型MTSTRE,构造出一种可证明安全的具体和通用方案,并严格证明所提具体方案在自适应选择明文攻击下是安全的。效率分析表明,与已有最有效的多时间服务器TRE解决方案相比,所提具体方案的计算效率也略有提高。 相似文献