Scrambling Encryption Methods And Scrambling Performance Evaluation For Vector Geographic Data

Aiming at the characteristic and the security requirement of vector geographic data, this paper has dissected the definition, principle and classification system of scrambling encryption. Then on this basis, it has designed and realized the scrambling encryption algorithms for vector geographic data. Finally, this paper analyzed the scrambling performance parameter and evaluation methods. Furthermore, it makes a comprehensive comparison with the scrambling performance of different scrambling algorithms. The proposed scrambling methods in this paper, which has the characteristics of high working efficiency, reliable security, randomness and reversibility, can encrypt optionally not only from one single respect but also considering relationships, attributes and locations, and improve the theory and methodology of geographic information security. The main contents and conclusions are as follows:(1) Scrambling encryption principle for vector geographic data. Based on the characteristic and the scrambling encryption requirement of the vector geographic data, it studied the definition and principle of encryption, and established the classification system of scrambling encryption methods for vector geographic data.(2) Research about scrambling encryption algorithms for vector geographic data. Based on the scrambling principle, the paper focused on research of scrambling encryption schemes suitable for vector geographic data and the organization of these schemes. Based on the characteristics of vector geographic data, it devised and realized the scrambling encryption algorithm based on two-dimension and the scrambling encryption algorithm based on quasi affine transformation. These proposed algorithms are simple, efficient, safe, reversible, and have better scrambling effect because they had achieved overall scrambling among the different element groups. The processed data has the same organizational structure and data formats with the original data.(3) Research about scrambling performance evaluation method for vector geographic data. This paper focused on research of the evaluation method based on the theory of fuzzy to show the differences between neighborhood factors, and a blind-evaluation method that does not rely on the original data. Finally, prototype experiments and performance analysis have been realized for the methods. The experiments results show that the above parameters can express the scrambling performance for vector geographic data effectively.