Flaw in the Enigma Code - Numberphile on HackerTube: recommended by 4 Hacker News commenters across 4 separate months, 2013–2025.
explainer · evergreen
Numberphile's Dr James Grime explains the flaw in the Enigma machine, namely that a letter could never be encrypted to itself, and how that helped the Allies break the code. It touches on the Bombe and Alan Turing.
HN points to it as a short, clear explanation of why Enigma was breakable and how search-space elimination works.
“Numberphile gives a nice, succinct explanation”
4 Hacker News comments link this video. Each one links back to its thread.
There's the entertaining bit in the film The Imitation Game (the breaking of Enigma code by Alan Turing) where they realised that a weakness was the daily weather report always containing the words "weatherreport" and "heil bloody hitler" (with obvious addition!) [link] or longer version: [link] Also a more proper explanation: ▶ this video
in “Encryption made for police and military radios may be easily cracked” · View on HN
none of it is "brute force", GNFS is a process that rapidly excludes numbers from the search space that cannot be the answer, in principle similar to the way they broke enigma. numberphile has a great video on that one ▶ this video Also, taking the OP as a "worse case", afaik: 512bit = $8 so 1024 = 8^2 = $64 2048 = 8^2^2 = $4,096 4096 = 8^2^2 = $16,777,216 noting $8 for 512 seems very expensive to me.
in “Cracking a 512-bit DKIM key for less than $8 in the cloud” · View on HN
In this case, a more relevant example from World War II might be the exploitation of flaws in the Enigma machine, namely: 1) the re-use of common phrases in weather reports, and 2) the fact that a letter could not be encoded as itself in the ciphertext, providing a mechanism of contradiction that drastically sped up elimination of possible settings [link] Numberphile gives a nice, succinct explanation ▶ this video
in “Forthcoming book seeks to visualise, locate and expose many numbers stations” · View on HN
Some people might like this from Numberphile which describes the flaw in the enigma machine that British code breakers used to eventually break the code. ▶ this video
in “The Enigma Machine: How Alan Turing Helped Break the Unbreakable Nazi Code” · View on HN