Research On Group Digital Signature And It's Application

As an important part of cryptography,digital signature technology has got extensive application due to its unique function to realize identity,authentication,data integrity prection and non-repudiation,particularly in large-scale network security systems communications and E-commerce. Digital signature have become indispensable to computer network security,to protect the reliability of data and to achieve safety certification.The main content of this paper is the research of the group member delete problem in group signature,and group signature's application.Our main works are given as follows:(1)Introduce theory of knowledge which is frequently used in cryptographyincluding:mathematical knowledge ;seurity assumptions in cryptography; symmetric cryptography and asymmetric cryptography;hash function and knowledge signature .(2)Give the formal definition of group signature.Summarize the main problem of the current group signature's work and the security requirement of a good group signature.Analys t.the security of the several important group signature.For the problem of group member delete,give the main problem.Prove two group signatures which have the funcation to delete member are not security.(3)Put the group signature into practice.Use the group signature and commit agreement to give a Sealed-bid Electronic Auction Scheme,analyst its security and efficiency.At the end of paper, envisage how to desigen the special group signature which can used in different circumstances.