Relational Database Based On Public Key Cryptography Watermarking Algorithm

With fast development of computer network,copyright protection of relational database is becoming the research hotspots.Copyright watermark can be embedded into database to solve these problems like muti-media digital watermark technology.Idea of public key knowledge is applied into database watermark and works are as follows:Firstly,the necessity and feasibility of introducing public cryptography into database watermarking is studied based on a systematic study on existing researches.Characters of applying asymmetry cryptogram in insetting,detecting and extracting pahses of database wateamrk are illustrated.Secondly,Chaotic public key based watermark algorithm is proposed by utilizing the permutation function of chaotic random public key.Chaotic sequence served as the private key of copyright watermark.It can be detected through permute public factor.In this way,secret information leakage of the wateamark is avoided.Next,public key algorithm based on RSA is presented.Security is guaranteed by the unilateralism,and we use the public watermark detection for large-scale protection with trusted third party.Watermark operation can be completed easily avoiding deceive availability. Experiment validates the robustness and feasibility of arithmetic.At last,correlation content of zero-knowledge in database watermark arithmetic based on public key cryptography is discussed.The database owner make the prover believe exist of the copyright watermarking without leaking corresponding knowledge of the key and give a conclusion.To sum up,the main contributions of this thesis include:demonstrating the necessity and feasibility of asymmetry watermark arithmetics based on public key cryptography in three aspects:chaos pubic key theory,RSA cryptogarm and the zero-knowledge.Analyses and experimental results show that the proposed algorithms have good performance.It has a nice forward in copyright protect of relational databases in pratice.