Caesar cipher and letter frequency: A statistical solution

• Matheus da Silva Santos IFMT

DOI: https://doi.org/10.5753/eri-mt.2024.245839

Abstract

This work explores the use of letter frequency analysis in solving substitution ciphers, using the Caesar cipher as the basis of the study. Using a combination of literary texts and musical lyrics, an algorithm was developed to normalize characters and calculate the frequencies of each letter. From the comparison between the frequency observed in a cipher text and the expected frequencies, it was possible to decipher the message by statistical approximation. The results demonstrate that statistical analysis is an efficient and practical solution for breaking simple ciphers.

Keywords: Caesar Cipher, Programming, Statistics

References

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