Robust optimal position detection scheme for relational database watermarking through HOLPSOFA algorithm

Nowadays, relational database watermarking is a challenging problem in many content distribution applications and internet-based application environments. The watermarking scheme for relational databases based on a hybrid algorithm, named as HOLPSOFA is proposed. In HOLPSOFA, the combination of Orthogonal Learning Particle Swarm Optimization and Firefly Algorithm is used. This new approach combines the advantages of Orthogonal Learning particle swarm optimization (OLPSO) and Firefly algorithm (FA), which can find the time-optimal solutions simultaneously. The overall relational database watermarking scheme consists of three stages, (1) Optimal location identification through HOLPSOFA algorithm, (2) Watermark embedding and (3) watermark extraction. The proposed HOLPSOFA algorithm is also compared with OLPSO and Firefly algorithm. The performance of the proposed watermarking method is analyzed through Mean Square Error (MSE) and normalized correlation (NC). Our extensive analysis illustrates that the proposed method is robust against various forms of database attacks, including insertion, deletion and alteration. Computer simulations show that the hybrid algorithm is very effective in diminishing different kind of attacks in terms of MSE and NC than existing algorithms.