基于序列密码的GIS矢量数据层次加解密方法

For now,there are the following shortcomings in the processing technology of GIS vector data content security: the low efficiency in encryption and decryption for GIS vector data, the slow transmission speed and low security of remote access to GIS vector data. In order to effectively balance the mass characteristics of GIS vector data, the progressive transmission requirements and safety protection for content of GIS vector data, this article refers to the thought of progressive encryption for multimedia data and multi-level security authorization, integrates chaotic stream ciphers technology with LOD ( Level of Detail ) technology, and now we have respectively got a deeper study on the LOD technology and stream ciphers technology in other applied fields. Based on this thought, the article processes the progressive transmission of GIS vector data based on LOD technology which implemented upon elements monotonic segmentation, so as to improve the transmission rate of GIS vector data by avoiding redundant data storage like as order-identity information; the article processes the hierarchical encryption for GIS vector data based on hierarchical key chains which constructed upon Hash function, so as to effectively improve the security of hierarchical encryption and decryption for GIS vector data; this article processes encryption and decryption for GIS vector data based on an encryption method of stream ciphers, so as to improve the processing efficiency of encryption and decryption for GIS vector data. And on the basis, a method of hierarchical encryption and decryption for GIS vector data is formed lastly, which can be used for progressive transmission and security hierarchical scheduling, and thus the method intends to realize rapid and efficient transmission and security access to GIS vector data in the field of geographic information system.