Questions tagged [shift-register]

Shift registers are at the heart of cryptography and error-correction. In cryptography they are the main tool for generating long pseudorandom binary sequences which can be used as keys for two communicating parties in symmetric cryptography. Practically all military cryptography makes use of them.

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Linear Feedback Shift Register Taps

Linear feedback shift register tap charts are availale for registers of length 3 to 168. Does anyone have a chart for register lengths from 168 to 256 or beyond?
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Question about obtaining a keystream from a linear-feedback shift register

For a homework question we are obtaining a keystream from a LFSR and I am slightly confused on which digits are used as the key. For example I have this table here, ...
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How to build a lsfr based on sequence $s_i = s_{i-1} + s_{i-4}$? [closed]

How do I know where my XOR gates go? What does the F2 stand for here? Also the next task is to generate the sequence (with initialisation vector $s_0 = 1, s_1 = s_2 = s_3 = 0$) until it becomes ...
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Cryptanalysis of a feedback shift reigister with an S-box

I’m just getting started on learning cryptography and here is a problem from exercises about which I'm totally confused: This is a 32-bit feedback shift register to encrypt some message. The register ...
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Shift-rotating random number generator

Let $\omega$ denote the set of non-negative integers. For $n\in\omega\setminus\{0\}$ define the rotation function $$\text{rot}_n:\{0,1\}^n \to \{0,1\}^n$$ by $x \mapsto x'$ where $x'_k = x_{k+1}$ ...
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