Journal of KIISE:Computer Systems and Theory (한국정보과학회논문지:시스템및이론)

Korean Institute of Information Scientists and Engineers (한국정보과학회)
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On the Characteristic and Analysis of FCSR Sequences for Linear Complexity

선형복잡도 측면에서 FCSR의 이론절인 특성 및 분석 연구

  • Published : 2005.10.01
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Abstract

We have derived the linear complexity of a binary sequence generated by a Feedback with Carry Shift Regiater(FCSR) under the following condition: q is a power of a prime such that $q=r^e,\;(e{\geq}2)$ and r=2p+1, where both r and p are 2-prime. Also, a summation generator creates sequence from addition with carry of LFSR(Linear Feedback Shift Register) sequences. Similarly, it is possible to generate keystream by bitwise exclusive-oring on two FCSR sequences. In this paper, we described the cryptographic properties of a sequence generated by the FCSRs in view of the linear complexity.

유한체 GF(p)에서 r=2p+1이 2-솟수이고, p에 대한 2의 위수 m을 가질 때, $q=r^e,\;(e{\geq}2)$를 연결정수로 갖는 FCSR의 생성된 출력 수열에 대한 선형복잡도를 구한다. 또한, 합산 난수 발생기(Summation Generator)는 LFSR의 출력 수열을 정수 합산하여 키 수열을 발생한다. 이와 유사하게 두개의 FCSR의 출력 수열을 상관관계에 안전한 비트별 논리합(bitwise exclusive-oring)을 이용한 이진 난수열 발생기를 제안하고, 선형복잡도 측면에서 출력된 수열의 암호학적 특성을 살펴본다

Keywords

References

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