A bit chain from the chaotic orbit is generated, and the position at which a plaintext block appears in the chain is found.Then record the number of iterations of the chaotic map as the cipher block.

• 即以混沌系统的控制参数和初始点为密钥，迭代混沌映射以便产生一个比特链，在该比特链中搜索明文分组，记下迭代次数作为密文分组。