Showing posts with label Codebreaking. Show all posts
Showing posts with label Codebreaking. Show all posts

Friday, January 02, 2009

A Crypto Problem

My #3 Son was reading Poe's The Gold Bug and so he and I were discussing solving crypto puzzles. My son mentioned the letter frequencies Poe gave and I said Poe was wrong. So I asked him if he was sure he remembered it correctly. My son said he was sure he remembered it correctly and got the book out to prove it. Of course I had read Poe many years ago, but I didn't remember the letter frequencies Poe gave. Here are the letter frequencies Poe gave in order from most common to least as:

e a o i d h n r s t u y c f g l m w b k p q x z

In Linotype usage the frequencies are:

e t a o i n s h r d l u c m f w y p v b g k q j x z

and like any good crypto puzzle solver let me put them one on top of the other:

e a o i d h n r s t u y c f g l m w b k p q x z
e t a o i n s h r d l u c m f w y p v b g k q j x z


Do any of you have an explanation for the differences at least among the most common letters? Was he trying to make it harder for his readers to solve the crypto puzzles he often published?

Should you care to read or re-read the story here is an on line version of The Gold Bug from Project Gutenberg. And here is a paperback version: The Gold-Bug and Other Tales.

Cross Posted at Classical Values

Sunday, October 28, 2007

The Enigma Variations

I have been watching Mind of a Codebreaker - video instead of blogging. I should be ashamed of myself, but I am not. It is a fascinating story about how the British broke the German codes. Ultimately it is also the story of the World's First Programmable Electronic Computer. It had 1,500 valves. What we in America call tubes. An amazing story. If you have the time and bandwidth well worth it. I have studied this subject from a number of different aspects over the years since I first read a book called The Ultra SecretThe Ultra Secretand I must say this is one of the best technical expositions of the Enigma story I have yet come in contact with. The part about "cribs" is very interesting. Until I read a book on Enigma technology a few years back I had never seen a good explanation of "cribs". The video covers the essence of "cribbing" very well.