网络环境下地图的混沌加密实用算法

Practical Map Encryption Algorithm Based on Chaos System Under Network Circumstance

针对地图的存储特性 ,提出了一个混沌序列加密算法 该算法首先用单向Hash函数把密钥散列为混沌映射的迭代初值 ,混沌序列经过数次迭代后才开始取用 ;然后将迭代生成的混沌序列值映射为ASCII码后与地图数据逐字节进行异或运算 考虑到实际计算中的有限精度效应 ,随步长改变混沌映射参数 采用实际的地图数据 ,经与DES及A5算法的比较表明 ,该算法效率高、保密性好。

Concerning the storage characteristics of digital map, a chaotic sequence encryption algorithm is presented. The user's key is first hashed as the seed of chaotic mapping by a Hash function. After several iteration steps, the chaotic sequences are mapped to ASCII codes, and using the ASCII codes to one by one XOR every byte of the map data. In order to avoiding the localization of the finite precision, we change the parameter of the chaotic mapping with step length. Comparing with DES and A5 algorithms, computing results show that our algorithm is fairly good in efficiency, security and simplicity.