代理签名

Digital signature ; proxy digital signature ; discrete logarithmic problems ; elliptic curve discrete logarithmic problems ; elliptic curve digital signature algorithm

数字签名；代理数字签名；离散对数；椭圆曲线离散对数；椭圆曲线数字签名

We have the pleasure to inform you that we have given the company's procuration to Mr./Ms

我公司已将代理签名权授与…先生／女士，谨此奉告。

Ms … who has been with us for many years,to sign for our company per procuration.

现特告为我公司服务多年的…先生／女士已授权代理签名权。

To sign for our company per procuration.

现特告为我公司服务多年的程先生已授权代理签名权。

This paper proposes the identity-based proxy signature scheme using the conjugacy search problem in the braid groups which are believed to be hard problem,and its security is also analyzed.

介绍了辫群的基本概念、两个重要性质和辫群中的困难问题，在此基础上，利用辫群上的共轭查找问题构造了一个基于身份的代理签名，并对它的安全性进行了分析。

We formalized a notion of security for partial delegation with warrant proxy signature schemes, i.e., existentially unforgeability under an adaptive chosen-message attack and an adaptive chosen-warrant attack. We compare the new model with the previous formal models and identify their weakness.

重新给出了具有证书的部分代理签名的安全定义，即适应性选择消息攻击和适应性选择授权文件攻击下的不可存在性伪造，建立了形式化安全模型。

Analyses of two nominative proxy signature schemes proposed by Seo et al.(2003) and Huang et al.(2004) are given in this paper. The results show that neither the scheme has the property of strong unforgeability.

摘要该文分析了Seo等(2003)和黄振杰等学者(2004)提出的两个提名代理签名方案，指出这两个方案都不具备强不可伪造性。

First of all, this thesis points out that Qian-Cao-Xue\'s scheme (the first threshold proxy signature scheme from bilinear pairings) does not possess the property of strong unforgeability, presents two attacks and proposes an improved scheme which can resolve the security problem existing in their scheme.

本文主要研究了面向群体的数字签名中的代理数字签名、群数字签名及其应用，对一些数字签名的安全性进行了分析，设计了一些具有附加功能的数字签名。

S scheme which is a combination of Mambo et al.\'s proxy signature scheme and Zheng\'s signcryption scheme. Our analysis demonstrates that their scheme cannot guarantee strong unforgeability, strong identifiability, non-repudiation, and prevention of misuse.

他们的体制本质上是Mambo等人的代理签名体制和Zheng的签密体制的结合，安全性分析表明他们的体制不能满足强不可伪造性、强可识别性、不可抵赖性，也不能防止滥用。

The difference between this scheme and others proxy multi-signatures was that no all original signers authorized the proxy signer who could sign a message on behalf of original signers.Only a part of original signers delegated their signing power to the proxy signer,and others signed by themselves.This scheme satisficed the need when part of original signers couldn't sign by themselves.

与一般的代理多重签名不同的是，一组原始签名人不是都将签名权授予指定的代理签名人，仅有一部分原始签名人授权，其余的是自己行使签名权，即实现了一组原始签名人只有部分成员不能行使签名权的要求。

If you are unfortunate enough to the lovelorn, please tell me, I will help you out, really, please contact me!

如果你不幸失恋了，请告诉我，我会帮助你摆脱困境，真的，请联系我啦！

China's plan to cut energy intensity by 20 percent and pollutant discharges by 10 percent between 2006 and 2010 is a case in point.

中国计划在2006年到2010间降低20%的能源强度和减少10%的主要污染物排放，就是一个这样的例子。