Transparent Encryption Characteristics Research On Digital Maps

With the rapid developemt of informationization process, the digital map has been widely used in the areas such as business, military and others. Its positions and functions in the information war have continued to increase for its characteristics of accurate positioning,easy operation and convenient update. However, the practicability and efficiency of encryption about digital map are not well, so the digital map has always been facing the security problems of illegal copying, malicious tampering and man-made leaking. For the security peoblems of the digital map,this paper in-depth studies encryption technology to seek for more efficient, practical and secure encryption scheme about digital map characteristics data.The main content of this paper is to design the digital map characteristic data transparent encryption scheme, and protect the digital map data security. First, this paper puts forward some improvement suggestions of Logistic Map, and treats it as digital map characteristic encryption algorithm. The Characteristic encryption algorithm is the core encryption algorithm of digital maps, and the procedure of the encryption algorithm is that the required key stream is brokem into parts and it is generated by using several Logistic chaotic maps in a sequential iteration way, and each Logistic Map associates by ciphertext. The key stream not only has the features that which are sensitive to the initial conditions, long cycle and excellent randomness, but also enhances sensitivity of key stream plaintext state deviation,so the randomness of the keystream has been further improved. At the same time, this paper applies RSA encryption algorithm to design key encryption scheme to protect the key information. Alfer that, on the basis of in-depth analysis of digital map data characteristic files,this paper takes the type of data Shapefile shp file attributes coordinate file and dbf file for example, and designs two encryption schemes which combined with the characteristic encryption algorithm, to protect the safety of spatial digital map data and attribute data. At the same time, the encryption scheme designs file filter driver in the kernel model, so the encryption scheme realizes automatic encryption and decryption operations without affecting the user's normal operation.Finally, under the laboratory environment, this paper respectively examines the transparent encryption scheme for digital map from the three aspects of function, efficiency and safety. The digital map transparent encryption scheme has realized the function of encryption of digital map through the experiment test. The characteristic encryption algorithm generates excellent randomness key stream which can be seen from the statistical data, so the encryption algorithm guarantees the security of encryption.