Relational Database Watermarking

Proving ownership rights on outsourced relational databases has become an important issue in today’s internet-based environments and in many content distribution applications. In this paper, we present a technique for proof of ownership based on the secure embedding of a robust imperceptible watermark in relational data. We formulate the watermarking of relational databases as an optimization problem and discuss efficient techniques to solve the optimization problem and to handle the constraints. Our watermarking technique is resilient to different watermark attacks because it uses a partitioning approach that does not require marker tuples. Our method overcomes weaknesses that are present in previously proposed watermarking techniques. Watermark decoding is based on mean of partitions and the bits decoded using majority voting algorithm. We implemented the conceptual algorithm of our watermarking technique and showed by experimental results that our technique is resilient to tuple deletion, alteration, and insertion attacks.