• Title/Summary/Keyword: linear feedback shift register

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Generalization of Galois Linear Feedback Register (갈로이 선형 궤환 레지스터의 일반화)

  • Park Chang-Soo;Cho Gyeong-Yeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.1 s.307
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    • pp.1-8
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    • 2006
  • This thesis proposes Arithmetic Shift Register(ASR) which can be used as pseudo random number generator. Arithmetic Shift. Register is defined as progression that multiplies random number D , not 0 or 1 at initial value which is not 0, and it is represented as ASR-D in this thesis. Irreducible polynomial that t which makes $'D^k=1'$ satisfies uniquely as $'t=2^n-1'$ over. $GF(2^n)$ is the characteristic polynomial of ASR-D , and the cycle of Arithmetic Shift Register has maximum cycle as $'2^n-1'$. Galois Linear Feedback Shift Register corresponds to ASR-2-1. Therefore, Arithmetic Shift Register proposed in this thesis generalizes Galois Linear Feedback Shift Register. Linear complexity of ASR-D over$GF(2^n)$ is $'n{\leq}LC{\leq}\frac{n^2+n}{2}'$ and in comparison with existing Linear Feedback Shift Register stability is high. The Software embodiment of arithmetic shift register proposed in this thesis is efficient than that of existing Linear Shift Register and hardware complexity is equal. Arithmetic shift register proposed in this thesis can be used widely in various fields such as cipher, error correcting codes, Monte Carlo integral, and data communication etc along with existing linear shift register.

Gradual Encryption of Image using LFSR and 2D CAT (LFSR과 2D CAT를 이용한 단계적 영상 암호화)

  • Nam, Tae-Hee;Kim, Seok-Tae;Cho, Sung-Jin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1150-1156
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    • 2009
  • In this paper, we propose the gradual encryption method of image using LFSR(Linear Feedback Shift Register) and 2D CAT(Two-Dimensional Cellular Automata Transform). First, an LFSR is used to create a PN(pseudo noise) sequence, which is identical to the size of the original image. Then the created sequence goes through an XOR operation with the original image resulting to the first encrypted image. Next, the gateway value is set to produce a 2D CAT basis function.The created basis function multiplied with the first encrypted image produces the 2D CAT encrypted image which is the final output. Lastly, the stability analysis verifies that the proposed method holds a high encryption quality status.

Image Encryption using LFSR and CAT (LFSR과 CAT을 이용한 영상 암호화)

  • Nam, Tae-Hee;Kim, Seok-Tae;Cho, Sung-Jin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.05a
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    • pp.164-167
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    • 2009
  • In this paper, we propose the image encryption using LFSR(Linear Feedback Shift Register) and 2D CAT(Two-Dimensional Cellular Automata Transform). First, a LFSR is used to create a PN(pseudo noise) sequence, which is identical to the size of the original image. Then, the created sequence goes through a XOR operation with the original image to convert the original image. Next, the gateway value is set to produce a 2D CAT basis function. Using the created basis function, multiplication is done with the converted original image to process 2D CAT image encipherment. Lastly, the stability analysis verifies that the proposed method holds a high encryption quality status.

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IMAGE ENCRYPTION USING NONLINEAR FEEDBACK SHIFT REGISTER AND MODIFIED RC4A ALGORITHM

  • GAFFAR, ABDUL;JOSHI, ANAND B.;KUMAR, DHANESH;MISHRA, VISHNU NARAYAN
    • Journal of applied mathematics & informatics
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    • v.39 no.5_6
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    • pp.859-882
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    • 2021
  • In the proposed paper, a new algorithm based on Nonlinear Feedback Shift Register (NLFSR) and modified RC4A (Rivest Cipher 4A) cipher is introduced. NLFSR is used for image pixel scrambling while modified RC4A algorithm is used for pixel substitution. NLFSR used in this algorithm is of order 27 with maximum period 227-1 which was found using Field Programmable Gate Arrays (FPGA), a searching method. Modified RC4A algorithm is the modification of RC4A and is modified by introducing non-linear rotation operator in the Key Scheduling Algorithm (KSA) of RC4A cipher. Analysis of occlusion attack (up to 62.5% pixels), noise (salt and pepper, Poisson) attack and key sensitivity are performed to assess the concreteness of the proposed method. Also, some statistical and security analyses are evaluated on various images of different size to empirically assess the robustness of the proposed scheme.

New Polyphase Sequence with Good Nonperiodic Autocorrelation Property (우수한 비주기 자기상관 특성을 갖는 새로운 다중 위상 부호열)

  • 문경하;홍윤표;최기훈;송홍엽
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7C
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    • pp.915-920
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    • 2004
  • In this paper, we propose the new polyphase sequence with the best nonperiodic autocorrelation property in the viewpoint of the merit factors, which are important criteria for a nonperiodic autocorrelation property. We propose the general implementation of a polyphase sequence generator over an integer residue ring by using a linear feedback shift register(LFSR), in addition, we analyze the linear complexities of polyphase sequences based on the proposed implementation method.

On the non-linear combination of the Linear Fedback Shift Register (선형 귀환 쉬프트 레지스터의 비선형적 결합에 관한 연구)

  • Kim, Chul
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.9 no.2
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    • pp.3-12
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    • 1999
  • We introduce feedback registers and definitions of complexity of a register or a sequence generated by it. In the view point of cryptography the linear complexity of an ultimately periodic sequence is important because large one gives an enemy infeasible jobs. We state some results about the linear complexity of sum and product of two LFSRs.

A Study on a Binary Random Sequence Generator with Two Characteristic Polynomials (두개의 특성 다항식으로 구성된 이진 난수열 발생기에 관한 연구)

  • 김대엽;주학수;임종인
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.12 no.3
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    • pp.77-85
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    • 2002
  • A Research of binary random sequence generator that uses a linear shift register had been studied since the 1970s. These generators were used in stream cipher. In general, the binary random sequence generator consists of linear shift registers that generate sequences of maximum period and a nonlinear filter function or a nonlinear combination function to generate a sequence of high linear complexity. Therefore, To generate a sequence that have long period as well as high linear complexity becomes an important factor to estimate safety of stream cipher. Usually, the maximum period of the sequence generated by a linear feedback shift register with L resistors is less than or equal to $2^L$-1. In this paper, we propose new binary random sequence generator that consist of L registers and 2 sub-characteristic polynomials. According to an initial state vector, the least period of the sequence generated by the proposed generator is equal to or ions than it of the sequence created by the general linear feedback shift register, and its linear complexity is increased too.

A Study on the Cryptographic Properties of FCSR Sequences (FCSR 난수열의 암호학적인 특성에 관한 연구)

  • 서창호;김정녀;조현숙;김석우
    • The KIPS Transactions:PartC
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    • v.8C no.1
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    • pp.12-15
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    • 2001
  • 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.

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Design of an LFSR Multiplier with Low Area Complexity (효율적인 공간 복잡도의 LFSR 곱셈기 설계)

  • 정재형;이성운;김현성
    • Journal of Korea Society of Industrial Information Systems
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    • v.8 no.3
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    • pp.85-90
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    • 2003
  • This paper proposes a modular multiplier based on LFSR (Linear Feedback Shift Register) architecture with efficient area complexity over GF(2/sup m/). At first, we examine the modular exponentiation algorithm and propose it's architecture, which is basic module for public-key cryptosystems. Furthermore, this paper proposes on efficient modular multiplier as a basic architecture for the modular exponentiation. The multiplier uses AOP (All One Polynomial) as an irreducible polynomial, which has the properties of all coefficients with '1 ' and has a more efficient hardware complexity compared to existing architectures.

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A Study of Security and Privacy and using Hash Lock Approach in Ubiquitous environment (유비쿼터스 환경에서 해쉬 락 기법을 적용한 보안과 프라이버시에 관한 연구)

  • Choi, Yong-Sik;John, Young-Jun;Park, Sang-Hyun;Han, Soo;Shin, Sung-Ho
    • 한국HCI학회:학술대회논문집
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    • 2007.02a
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    • pp.790-795
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    • 2007
  • 최근 유비쿼터스 컴퓨팅에 대한 연구가 활발히 진행되고 있으며 유비쿼터스 컴퓨팅의 실현을 위한 핵심기술로서 RFID 시스템에 대한 연구가 활발히 진행되고 있다. 유비쿼터스 환경에서 RFID 시스템이 사용자의 편리함을 가져다 주는 장점이 있는 반면, 이로 인해 사용자의 프라이버시가 침해 당할 수 있는 문제점 또한 가지고 있다. 본 논문에서 사용자 인증 알고리즘은 새로운 해쉬 함수를 사용하고 그리고 메시지 암호화를 위한 스트림 암호기는 LFSR(Linear Feedback Shift Register)을 사용한다.

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