Researches And Application On PKI And Digital Watermarking In The Electronic Seal System

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.