An Effective Approach for Non-Numeric Relational Database Verification

With the large distribution of digital data, protecting their integrity becomes necessary and digital watermarking has been proposed as solution for protecting the content of relational database. Previous watermarking techniques mainly focus on the numeric database authentication by inserting watermark bits in digital data which may greatly degrade the data quality. In this paper, we present a distortion free approach to verify the integrity of a combined numeric and non-numeric relational database. The technique first partitions the database in different groups of square matrices, then the ASCII code of non-numeric data of group attributes are computed and used to generate the watermark. Security analyzes and experiments demonstrated that the proposed technique is resilient against malicious attacks and moreover the tampering can be detected up to group level.