Research And Implementation Of Electronic Seal System Based On Digital Signature And Quadratic Residue

Along with the rapid development of the electronic commerce and electronicgovernment, the office automation becomes wider and wider. A lot of documents needtransferred by Internat/Internet, including some high secret ones. Research on electronicseal system with high security and efficiency has an important scientific and academicvalue. Moreover it has an important significance to the development of our nationalelectronic commerce and electronic government. However, electronic seal is still on thestage of research and development so far. Many technical problems such as higherefficiency, higher security and how to authenticate haven't been solved completely.This paper proposes one new electronic seal scheme, and designs and implements aelectronic seal system based on SHA-1 Hash function, the Elliptic Curve DigitalSignature Algorithm, and watermarking algorithm based on quadratic residue. It shoulddevote to the research of electronic seal. This system has a value of wide application andgreat perspective at the times when the network security gets great concerns.Firstly, this paper introduces the basic knowledge of electronic seal, includingresearch status home and abroad, main system models and key technologies.Secondly, it proposes one new electronic seal system based on digital signature andquadratic residue. Aiming at the problem that most seal system electronic document andseal picture don't integrate well, it carries out embedding, extracting and authenticationby using the watermarking algorithm based on quadratic residue. It also solves theproblem of integration between electronic seal and Word. It implements displaying sealvisually in the Word document.Finally, an electronic seal system is designed and implemented by selectingclient/server design structure. The basic functions are developed on the platforms ofVisual C++ 6.0 and Visual Basic 6.0, including the integration between electronic sealand Word application by using COM technology, and the integration between digitalsignature and Digital Image Processing.