A Copyright Protection System Based On Digital Signatures And Time Stamps

With the rapid development of science and technology,the image is spreading faster and faster on the network.The infringement is especially serious,which brings incalculable losses to the image creators.However,due to the difficulties of identification of image theft and the high cost of litigation,victims often choose to bear the image infringement,which also contributes to the proliferation of the phenomenon of image theft.Therefore,the research of copyright protection technology has become one of the key problems to be solved.With the help of digital signature technology,this paper constructs a convergable DSA signature scheme,proposes a time stamp based verifiable message delivery scheme,and applies it to image copyright protection system.The innovation of this paper is as follows:(1)In this paper,a convergable DSA signature scheme is proposed.The advantage of this scheme is that the signatures of multiple users on the messages are converged into a short signature in sequence.The verifier only needs to verify the converged signature,which greatly improves the efficiency of signature.The random value is regenerated by the method of Horngin the literature to reduce the complexity of modular inversion.Performance analysis shows that the signature efficiency of the scheme has been greatly improved.(2)Construct a time stamp based verifiable message delivery scheme.This scheme adds time stamp to the message digest and records its generation time.Then,by using encryption algorithm and combining with the convergable DSA signature scheme,a verifiable message delivery scheme based on time stamp is proposed.Under the premise of ensuring security,the encryption and decryption times of the message delivery scheme can be reduced by reducing the encryption and decryption times of the public and private keys of the receiver,and the execution efficiency can be improved by reducing the signature verification time combined with the aggregation signature.At the same time,the non-repudiation of the sender and the receiver can be prevented.Performance analysis shows that the security and calculation efficiency of the scheme have been further improved.(3)Design and implementation of image copyright protection system.In view of the defects and application mode of the existing digital image copyright protection scheme,based on the proposed verifiable message transmission scheme with time stamp,this paper designs and implements a digital image copyright protection system.The system can realize the functions of copyright registration,copyright ownership and evidence of rights protection,which has a good application prospect.