“This telegram must be closely paraphrased before being communicated to anyone”

Post by [deleted] » Sun, Aug 31, 2025, 2:57 PM UTC

jameshart wrote: post #9

vertnerd wrote: post #6

This is a familiar concept from reading about WW2 spy stuff (Between Silk and Cyanide, for example, which I highly recommend). But what REALLY intrigues me is the typeface of the letter with its upper-case 'E' used in place of 'e'. What's up with that?

That is peculiar. Brief internet search turned up a Reddit post where someone had a sample of typed text with the same odd typography: https://www.reddit.com/r/typewriters/s/f2CIY0TCm3 The suggestion that it may have been a striker from a bilingual - cyrillic typewriter that was mixed in is an interesting possibility; someone transcribing diplomatic telegrams in WWII may indeed have need of access to Cyrillic typewri…

Post by maxbond » Sun, Aug 31, 2025, 3:03 PM UTC

jameshart wrote: post #19

eszed wrote: post #14

Earlier quoted context omitted.

No. As explained in the SO answer, the worry is that the enemy will have been able to decrypt one or the other of your messages, at which point the identical underlying plaintext will help them crack the second cypher.

‘Crack the cipher’ in this case most likely meaning: figure out the daily code word key you are using for that cipher. If they have already gained the ability to decrypt today’s messages from station A in cipher A, and can therefore recover the plaintext of those messages; if they then find a message of the same length sent from station B in cipher B they can guess that that might be the same message, reverse enginee…

Post by dtgriscom » Sun, Aug 31, 2025, 3:04 PM UTC

xtiansimon wrote: post #8

Interesting. I liked the explanations in the accepted answer. This rule especially,“Never repeat in the clear the identical text of a message once sent in cryptographic form, or repeat in cryptographic form the text of a message once sent in the clear.” As a child I learned about codes from a library book. Fascinated with one-time pads, I convinced a friend to try a correspondence. We exchanged a few messages, and th…

Post by macintux » Sun, Aug 31, 2025, 3:11 PM UTC

gametorch wrote: post #13

Tangentially related — sending everyone in a company a slightly different document can help catch the person leaking confidential documents to the press.

Post by ants_everywhere » Sun, Aug 31, 2025, 3:23 PM UTC

vertnerd wrote: post #6

This is a familiar concept from reading about WW2 spy stuff (Between Silk and Cyanide, for example, which I highly recommend). But what REALLY intrigues me is the typeface of the letter with its upper-case 'E' used in place of 'e'. What's up with that?