An improved identity-based proxy ring signature scheme

Proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. In this paper, we point out that Lang‘s scheme is unreasonable and propose an improved Identity-based proxy ring scheme from bilinear pairings which is reasonable and overcomes the deficiencies of Lang‘s scheme. Our scheme can prevent the original signer from generating the proxy ring signature, thus the profits of the proxy signer are guaranteed. In addition, our scheme satisfies all the security requirements of proxy ring signature, I.e. Signer-ambiguity, non-forgeability, verification, non-deniability and distinguishability. As compared with Zhang‘s scheme, our scheme is a computational efficiency improvement for signature verification because the computational cost of bilinear pairings required is reduced from O(n) to O(1).     

An Improved Identity-Based Society Oriented Signature Scheme with Anonymous Signers

In this paper, we present an improved identity-based society oriented signature scheme with anonymous signers, which satisfies： （1） when members leave or join an organization, the public verification key and the signature verification procedure are unchanged; （2） a user participates in several organizations at the same time, her secret key is only related with her identity. However, no previous schemes have these two properties.     

An Identity-Based Strong Designated Verifier Proxy Signature Scheme

0 IntroductionIn 1996 ,Jakobsson, Sako and Impagliazzo introduced anew pri mitive called designated verifier proofs[1]. Suchproofs enable a prover Signy to designate who will be con-vinced by a proof .Furthermore,Jakobsson,Sako and Impa-gliazzo proposed a designated verifier signature. Designatedverifier signatures provide authentication of a message, with-out having the non-repudiation property of traditional signa-tures . They convince one-and only one-specified recipient thatthey are va…     

A New ID-Based Proxy Blind Signature Scheme

An identity-based proxy blind signature scheme from bilinear pairings is introduced, which combines the advantages of proxy signature and blind signature. Furthermore, our scheme can prevent the original signer from generating the proxy blind signature, thus the profits of the proxy signer are guaranteed. We introduce bilinear pairings to minimize computational overhead and to improve the related performance of our scheme. In addition, the proxy blind signature presented is non-repudiable and it fulfills perfectly the security requirements of a proxy blind signature.     

An efficient identity-based anonymous signcryption scheme

Signcryption is a cryptographic primitive that performs encryption and signature in a single logical step more efficiently than sign-then-encrypt approach. Till now, various kinds of signcryption schemes have been proposed. Among them, the requirement of signcrypter＇s privacy protection is needful in some practical applications. In this paper, a new identity-based anonymous signcryption scheme from hilinear pairings, which is the organic combination of identity-based ring signature and encryption scheme, is proposed. The proposed scheme is indistinguishable against the chosen ciphertext attack under the Decisional Bilinear Diffie-Hellman assumption in the random oracle model. Its unforgeability relies on the computational Diffieellman problem. Compared with the previous schemes, the new scheme is more efficient in computation.     

支持多中心聚合签名的实用性拜占庭容错改进方案

为了解决区块链共识机制中验证效率偏低问题,将聚合签名方法应用于共识过程中的消息验证,改变共识过程中传统的单签名验证方式,从而降低共识过程中的验证复杂性;为了解决密钥中心权限过大问题,结合分布式密钥生成技术实现多中心的密钥授权机制,使共识节点的密钥生成不再依赖于单可信中心,从而避免密钥托管问题;以实用性拜占庭容错方案为例,构造基于多中心聚合签名的拜占庭容错共识改进方案。仿真实验表明,相对传统的实用性拜占庭容错方案,所提方案效率更高。     

An identity-based scheme of fair exchange of digital signatures

Fair exchange of digital signatures is an important tool for signing digital contracts, e-payment and other electronic commerce actions. An ID-based scheme of fair exchange of digital signature is proposed in this paper. The protocol relies on a trusted third party, but is ＂optimistic＂, in that the third party is only needed in cases where one player attempts to cheat or simply crashes. The proposed scheme has properties of short signature, low computation and verification cost. It can realize exchange of digital signatures fairly and effic, iently. A key feature of our scheme is that it is identity-based, which needs no certificates and has a simple key management. To our best knowledge, this is the first identity based scheme of fair exchange of digital signatures.     

Efficient ID-Based Proxy Blind Signature Scheme

0 Introduction Ablind signature, primitively introduced by Chaum[1], plays a central role in cryptographic protocols such as e-voting,e-payment that require user anonym- ity[2,3]. Such a signature allows a user to obtain a signa- ture of a message in a wa…     

一种改进的基于身份和双线性对的环签名方案

Lin-Wu等人的使用双线性对构造的基于身份的环签名是不合理的,该文对Lin-Wu等人的签名方案进行修改,得到一个合理的使用双线性对构造的基于身份的环签名。     

无完全可信PKG身份签名的分层CES方案

针对管理型SaaS应用整体签批分层处理业务中隐私保护的需求,提出了一种无完全可信私钥生成中心（private key generator,PKG）身份签名的分层内容摘录签名（content extraction signature,CES）方案。采用分层摘录策略控制分片和签名摘录,基于身份签名克服了公钥基础设施证书管理复杂的问题,由租户和服务提供商的PKG独立生成用户私钥分量,在一定程度上克服了无完全可信PKG问题。分析表明,该方案具有用户私钥的私密性、CES的隐私性和不可伪造性,可推广应用于在线办公、在线图书销售等方面。     

基于身份的密钥隔离聚合签名

针对基于身份的聚合签名系统中密钥泄漏的问题,给出了基于身份的密钥隔离聚合签名的概念,同时提出具体的基于身份的密钥隔离聚合签名方案。该方案运用密钥隔离技术实现对每个签名者的私钥定时更新,在签名者密钥泄漏不可避免的情况下,减少了密钥泄漏带来的危害。此方案满足密钥隔离安全、强密钥隔离安全和安全密钥更新等性质,并且验证时只需要常数个双线性配对运算,大大提高了签名的验证效率。     

新的基于身份的代理盲签名方案及其应用*

代理盲签名技术是指由原始签名者授权的代理签名者在不知晓待签名的消息的具体内容的情况下完成签名的技术。代理盲签名技术可以保证消息的匿名性,将签名权外放,减轻签名者的负担,同时能保证签名的安全性,常被用于电子商务,电子现金交易和电子投票方面。提出了一个新的基于身份的代理盲签名方案,论证了方案的正确性和安全性,证实了该方案具有较高的效率,并阐述了其在电子现金领域的应用,尤其是在使用移动终端进行购物方面的应用。     

标准模型下基于身份的门限密钥隔离签名

为了减轻基于身份的签名系统中密钥泄漏所带来危害,运用Weng等的门限密钥隔离机制设计了一个基于身份的门限密钥隔离签名方案.所提方案的安全性证明是基于标准模型的,即不需要随机预言机.     

Identity-based ring signature scheme based on quadratic residues

Identity-based (ID-based) ring signature has drawn great concerns in recent years and many ID-based ring signature schemes have been proposed until now. Unfortunately, all of these ID-based ring signatures are constructed from bilinear pairings, a powerful but computationally expensive primitive. Hence, ID-based ring signature without pairing is of great interest in the field of cryptography. In this paper, the authors firstly propose an ID-based ring signature scheme based on quadratic residues. The proposed scheme is proved to be existentially unforgeable against adaptive chosen message-and-identity attack under the random oracle model, assuming the hardness of factoring. The proposed scheme is more efficient than those which are constructed from bilinear pairings.     

公平的基于身份的有向签名方案

 为了保护签名接收者的隐私,有向签名方案要求签名的验证必须得到接收者或签名者的合作.利用椭圆曲线上双线性映射的基于身份的密码体制,提出了一个公平的基于身份的有向签名方案.当签名者与验证者发生争议时,在二者的协助下,可信第三方能够进行公开验证签名.结果的分析表明,所提方案与同类方案相比签名长度更短并且通信代价更小.     

A New Threshold Signature Scheme Using Self-Certified Public Keys

To prevent active attack, we propose a new threshold signature scheme using self-certified public keys, which makes use of hash function and discrete logarithm problem. The scheme has less commutnication and computation cost than previous schemes. Furthermore, the signature process of the proposed scheme is non-interactive.     

无证书密钥隔离签名方案

由于移动互联网络的快速发展,如何保障签名过程中用户私钥在不安全的环境中不被泄露,成为倍受关注的问题。为了降低密钥泄露带来的危害,密钥隔离成为核心解决方法之一。文献[8]提出了一个基于身份的密钥隔离签名方案,并且在标准模型下证明了该方案的安全性。但在实际应用中文献[8]的方案是存在密钥托管问题的。为了弥补文献[8]中基于身份方案的不足,提出了一种无证书的密钥隔离签名方案。该方案不仅具有基于身份密钥隔离签名方案的核心功能,而且解决了基于身份密钥隔离签名方案中存在的密钥托管问题。     

一种被指定的多重代理签名方案

给出一种称为被指定的多重代理签名方案 .在这种新方案中 ,原始签名人可授权多个代理签名人 ,分散了代理签名人的签名权力     

A Signature Scheme with Non-Repudiation

Based on the Schnorr signature scheme, a new signature scheme with non-repudiation is proposed. In this scheme, only the signer and the designated receiver can verify the signature signed by the signer, and if necessary, both the signer and the designated receiver can prove and show the validity of the signature signed by the signer. The proof of the validity of the signature is noninteractive and transferable. To verify and prove the validity of the signature, the signer and the nominated receiver needn＇t store extra information besides the signature. At the same time, neither the signer nor the designated receiver can deny a valid signature signed. Then, there is no repudiation in this new signature scheme. According to the security analysis of this scheme, it is found the proposed scheme is secure against existential forgery on adaptive chosen message attack.