Sequence cipher realization device and sequence cipher realization method thereof

The invention relates to a sequence cipher realization device and a sequence cipher realization method thereof. The method comprises the following steps: firstly, generating a sequence source by adopting Galois-structure nonlinear feedback shift registers designed based on mixing and diffusion parts as a sequence source drive; and then, after the registers load keys, initialization vectors and constant parameters completely, carrying out idle operation for a certain number of beats, carrying out nonlinear operation on an output of the diffusion unit so that the output is taken as a key stream sequence, and carrying out exclusive or operation on the key stream sequence together with a plaintext sequence to form a ciphertext. According to the sequence cipher realization device and the sequence cipher realization method thereof disclosed by the invention, relatively less operation and hardware cost can be used; through combined use of the mixing unit and the diffusion unit, after multiple times of iterations, a