An Exact Authentication Algorithm for Vector Geographic Data Based on Fragile Watermarking Technology

The fragile watermarking technique has been viewed as an effective method for content authentication, which not only can detect any modifications but also can locate the modified areas. In this work, an exact authentication scheme was developed to accurately detect malicious attacks while ensuring an exact location for the tampered area. Our innovative strategy uses the spatial relationships between elements of data points to establish links between elements and accurately remove vector data. Initially, our approach extracts the numerical coordinate values for the original fragile watermark. Then, the watermark information in accordance with quantitative data points embedded in the adjacent area are sorted. Furthermore, the extracted watermark and the original watermark are compared. During authentication, the extracted watermark and the original fragile watermark are compared depending on whether the authentication data are consistent with the fragile watermark. Thus, the modified positions are detected. Finally, many tamper attacks are applied and analyzed to test the fidelity and fragility of the algorithm by experiments. Our findings verify that the algorithm has an excellent performance for tamper detection, especially for deleting elements.