Research On Watermarking Relational Database Based On Nonnumeric Data

With the rapid development and wide application of the database and Internet, and the increasingly integration of them, the security problem of the database is getting more and more attention. How to prevent the diffusion of the unauthorized database's contents has become one of the key issues in the field of database security. At present, the technology of digital watermarking is such an effective method to protect the copyright of digital produces.Based on the analysis of the existing database digital watermarking methods a new database watermarking schema based on non-numerical attributes is brought forward and constructed in this paper, in which details such as the structure system, function system and detail design have been deeply studied as well. The main work and creative results are as follows:(1) Analyses different database watermarking method and summarizes the general method of watermarking insertion and detection based on non-numerical attributes.(2) By using of word similarity technology, designed and constructed a digital watermarking scheme for non-numerical attributes of database, and designed a model of the watermarking, the model is Composed of three parts:pretreatment process, the watermark embedding and watermark detection process.(3) For watermark embedding, plans the watermark embedding processes, it is divited into inserting site selection, watermark bit choice and the actual watermark embedding, and the design is completed the corresponding processing algorithms; through analysis of the embedding process simulation modify the parameters in the volume of data and the impact of watermark invisibility, the results show that the value of the data, the watermark embedded in the same capacity under this embedding algorithm is better than other similar algorithm.(4) For watermark detection, plans a watermark detection processing, it is divided into watermark bit location, watermark bit calculation and majority vote, and then completed the design of the corresponding processing algorithms. On the analysis of watermark detection algorithm and the ability to withstand various attacks, the watermarking algorithm simulation experiment results show that the watermarking algorithm has higher resistance to attack.