基于FCSR的双滤波密钥流生成器

当前，由于还没有一个适于一般目的的流密码国际加密标准，流密码的设计与分析引起了广泛关注。在以前的流密码的设计中多采用线性反馈移位寄存器（LFSR）作为基本的部件。然而由于LFSR本身的线性性，基于LFSR的流密码备受攻击，进而相继出现了一些替换部件，例如T函数，带进位的反馈移位寄存器（FCSR）等等。文中给出了一个新的基于FCSR的密钥流生成器。理论分析表明该密钥流生成器具有高度的安全性。NIST统计测试表明该密钥流生成器的伪随机特性是理想的。

FCSR-based Keystream Generator with Double-Filters

Since there are no general-purpose international stream cipher encryption standards,much attention has been paid to the design and analysis of stream cipher.Previously,the linear feedback shift register (LFSR) has been widely used as a basic design component.However,quite a few LFSR-based proposals have withstood cryptanalysis for its inherent linear structure.As a result,some alternative constructions have been proposed,such as T function,Feedback with Carry Shift Registers (FCSR) and so on.In this paper,a novel FCSR-based stream sequence generator is proposed.Theoretic analysis shows that the proposed keystream generator has high security.And the NIST statistical test indicates that the pseudo-random properties of this novel keystream generator are realtively ideal.