Cryptology Quotes

“The strength of a cryptographic system usually has less to do with its design than with the way people tend to use it. Humans are the weak link. Instead of changing keys or passwords at regular intervals, we use the same ones over and over, for weeks or months or years. We repeat the same words (such as "secret") at the start of multiple messages, or repeat entire messages multiple times, giving codebreakers a foothold. We choose key phrases that are easy to guess: words related to where we live or work, our occupation, or to whatever project we're working on at the moment. A couple of human mistakes can bring the safest cryptographic system in the world to its knees.”
― Jason Fagone, The Woman Who Smashed Codes: A True Story of Love, Spies, and the Unlikely Heroine who Outwitted America's Enemies

“Some rich men go in for art collections, gay times on the Riviera, or extravagant living, but they all get satiated. That's why I stick to scientific experiments, spending money to discover valuable things that universities can't afford. You never get sick of too much knowledge”
― George Fabian

“The first step was usually very simple: count the letters in the cryptogram. In English, the most frequently used letter is E, the most frequent two-letter group is TH, and the most fre-quent three-letter group is THE. So if you count the letters in the ciphertext and the most common letter is B, it might stand for E, and if the most common three-letter group is NXB, it might stand for THE.

You can count other things in a cryptogram, like the total number of vowels and consonants, and how often particular let-ters or groups of letters appear before or after other letters. All of these counts give hints to the hidden structure. A frequency count can also reveal if the plaintext was written in English, German, French, Spanish, or some other language, because the frequency of letters in a language is like a unique signature. The most common six letters in German, starting with the most common, are E, N, I, R, T, S. In French, E, A, N, R, S, I. In Spanish, E, A, O, R, S, N.”
― Jason Fagone, The Woman Who Smashed Codes: A True Story of Love, Spies, and the Unlikely Heroine who Outwitted America's Enemies