Showing Posts For XOR

Frequency Analysis on Repeating-key XOR

Repeating-key XOR is a simple, yet good exercise to learn how structure betrays secrecy. I’ll walk through the basic idea behind the encryption and how it can be broken: the intuition, the practical steps I thought of. I’ll also add a mention to a simple cipher I built months back, the Bit Flip Cipher and why the same weakness applies.

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Bit Flip Cipher: My First Attempt at Making a Cipher

A few months back, I found myself with an idea: what if I tried making my own cipher, just for fun? I hadn’t studied cryptography at all at that point, but I wanted to see how far I could go. That’s how Bit Flip Cipher came into existence.

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Fibonacci LFSR: How it works and How to Attack it

The Fibonacci Linear Feedback Shift Register is a classic example of a simple pseudo-random generator. It is often introduced in the study of stream ciphers and cryptanalysis because, while it can produce long pseudo-random sequences, its linearity also makes it vulnerable to attacks.

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