【作者】 张沈斌；

【导师】 刘全；

【作者基本信息】 苏州大学 ， 计算机应用技术， 2011， 硕士

【摘要】 在互联网飞速发展的今天,随着办公自动化技术在政府和企业中的大量应用,自动化办公应用正变得越来越广泛,其高效、节约资源的优势也日益凸显。而在自动化办公中,如何保障电子文档的完整性、机密性、文档发送者身份的可认证性以及签署人的抗抵赖性成为亟需解决的问题。电子签章技术正是在此背景下提出的,并成为当前信息安全技术领域和计算机应用领域研究的热点和难点。本文研究并设计了基于数字签名与数字水印认证的电子签章系统。该系统将数字签名、易损水印、鲁棒水印相结合,基于数字签名与数字水印的认证机制,使用COM组件技术,实现了文档认证、身份认证,图章版权保护等功能。理论分析与实践证明,该系统具有较强的安全性、实用性、易用性。本文的主要研究内容包括以下三个方面:(1)在分析研究实现电子签章系统相关的数字签名技术和公钥基础设施(public key infrastructure,PKI)技术等的基础上,讨论了基于PKI体系的电子签章系统及其安全性。(2)介绍数字水印技术的理论基础,将数字签名与数字水印作比较,针对数字签名在保障电子签章系统安全性中的缺陷,提出了一种结合数字签名与数字水印的电子签章加密算法。实验结果表明,该算法对基于PKI体系的电子签章方案进行了改进,能大大提高电子签章系统的安全性,加大了对“电子图章”的版权保护。(3)针对电子签章系统中的电子签章证书签发管理系统与基于Office文档的电子签章应用系统进行了详细分析并提出了该系统的设计方案,最后给出了基于Word 2003与Excel 2003应用的具体实例。更多还原

【Abstract】 Today, the internet is developing rapidly, and with the office automation technology in a large number of government and enterprise applications, office automation applications are becoming more popular. The advantages of high efficiency and resource conservation are also increasingly prominent in the process of office automation. How to protect the integrity and confidentiality of electronic documents, how to confirm the identity of the document sender, how to prevent the signer deny the signature, these problems need to be solved. Electronic seal technology is proposed in the background of the above. Electronic seal technology now has become the hot and difficult point of the field of information security technology and computer applications.This paper researches an electronic seal system based on digital signature and digital watermarking. Combining with digital signatures, fragile watermarking, robust watermarking, the system is based on authentication mechanism. It used com component technology and implemented the function of the document authentication, identity authentication and seal copyright protection. Theory and practice proved that the system has improved significantly in the information security of electronic documents protection.The main research contents are concluded as follows:i. Analysis and researches digital signature and PKI technology with the relation of the electronic seal system. The electronic seal system based on PKI and the safety of the system is discussed.ii. The theoretical basis of digital watermarking technology is instructed. Compared with the digital signature and digital watermarking technology, in order to improve the safety of signature digital in the electronic seal system, an electronic seal encryption algorithm combining with digital signature and digital watermarking is proposed. The result of experiment shows that the algorithm has improved the safety of the electronic seal system and the function of protecting the copyright of the electronic seal is enhanced.iii. Electronic seal certificate management system and electronic seal system based on office document are analyzed and designed. The application of electronic seal system in Word 2003 and Excel 2003 is demonstrated.更多还原