Three Types Of New Digital Signature Scheme Study

The advance of computer and network technology accelerates fast development of theInternet. The Internet is affecting our life and work in all sides. The Internet provides us theconvenient and efficient information service, but at the same time, it brings us all kinds ofsecurity problems for its opening and sharing character. And the information securitybecomes more and more important. As an important technology of information security,digital signature acts more importantly in data integrity, privacy and undeniability. At thesame time, along with the wide use of information technology in business, finance and law,digital signature faces severe challenge.Group signature is a new digital signature technology proposed by D Chaum and E vanHeyst in 1991. In a group signature scheme, any member of the group can sign a messageanonymously in behalf of the group. In practice, the number of the group member oftenchanges, adding or deleting, and so it is an important problem in group signature applicationhow to add and delete a group member securely and efficiently. But in member revocationthere is no secure and efficient implementation scheme at present. The current scheme iseither insecure or correlates linearly with the number of members to be revocation.Traditional digital signature schemes only suit to one to one communication.Multi-signature is required when there is several subscribers. Digital signature based onXML is designed for the application of digital signature to XML document. XML documentcould easily be signed partly, and so favors to the implementation of multi-signature. Alongwith the multi-signature's development and XML technology's wide use, multi-signaturebased on XML has wide application prospect.In order to restrict the arbitrary diffuse of digital signature, Chaum and Van Antwerpenproposed undeniable digital signature concept. But undeniable signature can only be verifiedwith the original subscriber's cooperation. And in order to avoid the deficiency of undeniablesignature, Chaum proposed confirmer signature concept. In a confirmer signature scheme, asemi-trusted third party, called confirmer, takes on the confirmation and negation of aconfirmer signature, and can convert a confirmer signature to a common signature. But thecurrent confirmer signature scheme is either insecure or low efficient, and so it has littlefeasibility in application.This thesis researches respectively on group signature, multi-signature and confirmersignature, and proposes several new digital signature implementation schemes. The mainwork of this thesis includes the following aspects:(1) After deep research on group signature technology, this thesis proposes two groupsignature schemes, one based on DSA, the other based on RSA, and then analyzes theirperformances.(2) After deep research on multi-signature technology, this thesis designs amulti-signature scheme.(3) After deep analysis and research on the confirmer signature technology, this thesisproposes a new confirmer signature scheme based on RSA, and then gives analysis of itsperformance in detail.(4) Based on the technology of digital signature scheme discussed before, the thesisdesigns an electronic signature system, and applies it to the assets management system ofhigher education school, and then implements the digital signature in assets increasemanagement.