基于数字水印和数字签名技术的电子签章系统的研究与设计-计算机软件与理论专业论文.docxVIP

I I 摘 要 本文提出了一种基于数字水印和数字签名技术的电子签章系统解决方案，在一定程度上解决 了电子签章系统的安全问题。 通过对目前多种流行的电子签章系统的研究和分析，发现大多数系统在开发时只是考虑到了 对文档的保护却忽略了对签章本身的保护，同时在要求高密传输的场合无法实现对接受方的身份 认证。在这样的系统中，签章很容易被伪造也就无法体现签章的权威性。针对该弊端，本文提出 了一种将结合数字水印脆弱性和鲁棒性特点的二层水印嵌入到签章系统和引入一种基于时间戳 的数字签名的方案，从而实现了文档唯一性、合法性、防接发双方抵赖性验证及对签章本身的合 法性和唯一性验证。在此基础上，以 PKI 技术为依托，设计并构建了一个集签章制作、签章应用 及签章服务功能为一体的通用电子签章平台，并对电子签章系统的各个功能模块和体系结构进行 了详细的说明，对系统涉及的应用接口和数据模式进行了详细的描述。 最后，给出了一个面向 Word 的客户端实例即通过 COM 组件技术将签章系统无缝接入到 Word 中，实现了对文档的签章和验章功能。实践开发表明，本文中提出的方案在一定程度上加 强了电子签章系统的安全性，为以后的研究提供了一种新的参考方法。 关键字：数字签名，数字水印，数字时间戳，电子签章，PKI II II ABSTRACT This paper puts forward a solution of electronic seal system, which based on digital watermark and digital signature, to some extent, solved the security problem of electronic signature system. Through researching and analyzing many popular electronic seal system, found that most of developers only considered document’s secures and ignored the protection seal itself. In the same time, most of the seal system cannot achieve the identity authentication between the receiver and sender in the occasion of g requirements of high transmission. In those systems, the signature is easy to be forged so the signature cannot reflect the authority of signatures’. This paper puts forward a method which combining the characteristics of the vulnerability and robustness of digital watermarking .In this paper we will introduce a method based on time stamp of digital signature scheme to fulfill the document uniqueness , legality, the validation and protect the both sides of the receiver’s legitimacy and uniqueness . On this basis, relying on PKI technology, design and construct a set seal production, which can support signature application and signature service function as one of general electronic signature platform, and to the electronic seal system modules and system structure, detailed description of the application of systems involve interface and data model in detail. Finally, we give an example for Word client through the COM c