【作者】 王娟；

【导师】 王晓峰；

【作者基本信息】 西安理工大学 ， 应用数学， 2007， 硕士

【摘要】 随着信息技术的高速发展和计算机网络技术的广泛应用,信息安全问题显得越来越重要,已经成为国内外计算机和网络应用领域普遍关注的热门研究课题。数字签名作为认证的主要手段,为信息安全提供了重要的技术支撑。群签名作为数字签名的重要分支,可以用来实现一些特殊的认证要求。本文对基于身份的群签名以及群签名中消息的机密性问题进行了深入地研究。主要工作如下:总结了群签名方案的发展历史和研究状况,并描述了群签名的定义、安全特性及其应用前景,同时对群签名的几种变体作了简要介绍。分析了基于身份的公钥密码系统的特点和基于身份的群签名方案。基于身份的公钥密码系统,虽然能够简化密钥的管理方式,但是系统必须无条件地信任私钥生成中心,这给基于身份的公钥密码系统的使用带来了限制。提出了一个无可信私钥生成中心的基于身份的指定接收者群签密方案。在该方案中,群签密者代表由n个成员组成的群对消息进行签密,只有指定接收者可以从群签密密文恢复出被签密消息的明文,从而验证群签密的有效性,并可以通过指定接收者进一步公开相关信息,转化为不泄露消息明文但可以被公开验证的群签名。该方案能够同时保证消息的机密性、可认证性和不可否认性。本方案为开放网络环境下的群体认证以及认证中的机密性提供了有效的解决方案。更多还原

【Abstract】 With the rapid development of information technique and the large-scale application of network technique, information security has been becoming more and more important, and is becoming a generally concerned research topic in domestic and international computer and network application field. As the main means of the authentication, the digital signature has provided an important technique for information security. As an important branch of the digital signature, group signature can achieve some special authentication requirements. In this paper, the identity-based group signature and the confidentiality of message in group signature are discussed. The main works are as follows:The research status and the development trend of the group signature are summarized. The concept, some secure properties and the applied foreground of group signature scheme are also described. At the same time, some variants of group signature are briefly introduced.The characteristics of identity-based cryptosystem and identity-based group signature scheme are analyzed. In general identity-based cryptosystem, the problem of key management can be simplified, but private key generator must be unconditionally trusted, which restricts the use of identity-based cryptosystem.An identity-based designated recipient group signcryption scheme without trusted private key generator was proposed. In the scheme, any member of the group can signcrypt on behalf of the group which is composed of n members. Only the designated recipient can recover the signcrypted plain message from the ciphertext to verify the validity of the group signcryption.The proposed scheme can also be converted into a group signature scheme with public verifiability by publishing the relevant information by the designated recipient, which does not disclose the plain message. Moreover, the confidentiality, authenticity and non-repudiation of message are guaranteed simultaneously. The proposed scheme provides effective solutions to group-oriented authentication and its confidentiality in open network.更多还原