Pro Cryptography and Cryptanalysis: Creating Advanced Algorithms with C# and .NET

© Marius Iulian Mihailescu and Stefania Loredana Nita 2021

M. I. Mihailescu, S. L. NitaPro Cryptography and Cryptanalysis https://doi.org/10.1007/978-1-4842-6367-9_23

23. Text Characterization

Marius Iulian Mihailescu¹   and Stefania Loredana Nita¹

(1)

Bucharest, Romania

 

In this chapter, we will analyze two important metrics for cipher and plaintext analysis: the chi-squared statistic and searching for patterns (monograms, bigrams, and trigrams). When working with classic and modern cryptography, text characterization as technique is a very important part of the cryptanalysis bag of tricks.

Chi-Squared Statistic

The chi-squared statistic is an important metric that computes the similarity percent between two probability distributions. There are two ...