Research Of Digital Watermarking Protocol Based On E1Gama1Algorithm

With wide application of the digitalized and Internet technologies, digital contents can beeasily copied and distributed without distortion, which makes it necessary for digital works to havehigher requirements of copyright protection. Using encryption technology alone may be unable tomeet these requirements, and more and more researchers began to study the digital watermark. As ahot research topic, digital watermarking has the advantages of security, provability, imperceptibilityand robustness, and can provide an effective solution to copyright protection problems, realizingcopyright protection, piracy tracking and copy protection of digital products. However, digitalwatermarking technology is inadequate in fully protecting copyrights. A complete security systemneeds secure watermark technology protocol, as well as reliable watermark watermarkingtechnology.This thesis first introduces the concepts, properties and key technologies of digitalwatermarking. We analyze some representative digital watermarking protocols in the literature,explore their advantages and disadvantages, and then summarize the key design points of a digitalwatermarking protocol. By analyzing the interactive protocol of buyers and sellers, proposed byMemon and Wong, and other watermarking protocols, we explore in this paper the issues to beimproved, and propose an improved protocol based on cryptography and digital watermarking.Current digital watermarking protocols often require frequent involvement of buyers, assumebuyers’ knowledge of signature or watermark, and do not consider appropriate usage control ofdigital products. In light of these drawbacks, we propose a secure, practical and extensiblewatermarking protocol, by utilizing the homomorphism, commutative El Gamal encryptionalgorithm and the machine fingerprint-based copyright control scheme. Besides, this protocol alsoconsiders the interests of both buyer and seller to some extent, and improves user experience with atransaction model similar to the traditional one.On the basis of the proposed protocol, we propose a simpler and safer second-hand tradingprotocol, and design a digital watermarking-based DRM system model. In comparison with theDRM model based on encryption technology, this system model ensures the security of digitalworks and piracy traceability, hence achieves a good absence authentication of piracy.