I was looking at some Enigma messages for some random reasons, and I wondered if there were ever issue pulling the correct words out the strings of characters of if there was a protocol for it. For instance, here is a decoded message from here:


As one can easily see, the words are just chained together, and therefore, strange things can happen. An example I came up with in English:


Which could be "kids exchange" or "kid sex change".

Were any protocols in place to protect against a vague message in Enigma or any other plain text encryption system?

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    $\begingroup$ I think there should be some strict rules about this. I wonder does anybody translate them from German. Here there is a mentioning about the encoding of space by X. $\endgroup$
    – kelalaka
    Jul 10 '19 at 14:01
  • $\begingroup$ @kelalaka That insertion of X must be it. XX is end of line, etc. $\endgroup$
    – b degnan
    Jul 10 '19 at 19:48
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    $\begingroup$ @kelalaka cryptomuseum.com/crypto/enigma/files/schluessel_m.pdf section 28; however, this still doesn't prevent something strange from happening as it's at the discretion of the operator. $\endgroup$
    – b degnan
    Jul 10 '19 at 19:59
  • $\begingroup$ That is a nice finding there. I'm using google translate... $\endgroup$
    – kelalaka
    Jul 10 '19 at 20:03
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    $\begingroup$ @kelalaka My family's language is German, so I could fight through it. That font is something else though. So J is quotes, XX is colon and X is spaces, but I don't know the other words. I'll have to dig into it when I have more time. $\endgroup$
    – b degnan
    Jul 10 '19 at 20:07

On page 5 of the document you linked in the comment it says the following in section 22:


Es werden ausgedrückt:

Punkt durch x, Doppelpunkt durch xx, Fragezeichen durch ud, Komma durch y, Trennungsstrich, Bruchstrich, Bindestrich durch yy, Klammer durch kk. Satzzeichen sind im allgemeinen nicht entbehrlich, Schlusspunkt ist nicht einzusetzen. Da Satzzeichen im Interesse der Kürzung des Spruches gestrichen werden, ist im Wortlaut auf Unmissverständlichkeit sorgfältig zu prüfen.

(My) Translation to English:


To express are:

Dot by x, colon by xx, question mark by ud, Comma by y, hyphen, line break, hyphen in words by yy, bracket by kk. Punctuation marks are generally not dispensable, the final dot is not to be used. The punctuation marks shall be deleted in the interest of shortening the sentence, the wording shall be carefully checked for unambiguity.

In section 28 there's also a short overview:

\begin{array}{|c|c|} \hline j - j & Highlighting \ signs \\ \hline x & Dot \\ \hline y & Comma \\ \hline ud & Question \ mark \\ \hline xx & Colon \\ \hline kk - kk & Bracket \\ \hline qu & Square \\ \hline grqu & Big \ square \\ \hline fpkt & Time \\ \hline sm & nautical \ mile \\ \hline yy & Hyphen, \space Line \ break, \space Hyphen \ in \ words \\ \hline \end{array}

So, as we can see, there's no special procedure to prevent vague messages. I would even argue that this could have been done intentionally, because the German language can have (very) long words and if you know the length of certain words it might be easier to decrypt a message.


Handwritten text on pages 23 & 25:

??? = The parts I can't quite read

Gestrichen ??? Ergänzende Anweisung [Befehlsnummer / Datum] gef. / gez. [Unterschrift]


Discarded ??? Additional instruction [Number of command / Date] private / signed [Signature]

I guess there was a command released that these instructions are not to be followed as written in this book. The soldier then crossed these pages out and signed it. "gef." is probably an abbreviation for "gefreiter" and is a rank in the military that can be compared to the English rank of private or soldier.

It could also be that it's "gez." (instead of "gef.") which would mean "signed" followed by the soldier's signature.

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    $\begingroup$ Thank you. As an aside, my mother spoke to me all through my childhood in German, I didn't know "question mark", and most of the punctuation words. That document was almost like a cyphertext even though I could talk to grandma. I was an interesting exercise. $\endgroup$
    – b degnan
    Jul 11 '19 at 10:24
  • $\begingroup$ Also, Alek, can you make out the handwritten text in pages 23 and 25. I'm curious why the section are crossed out. $\endgroup$
    – b degnan
    Jul 11 '19 at 12:51
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    $\begingroup$ @bdegnan Extended my answer, unfortunately it was really hard to read the handwritten text. $\endgroup$ Jul 11 '19 at 13:25
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    $\begingroup$ Thank you. This is all very interesting from a historical perspective. $\endgroup$
    – b degnan
    Jul 11 '19 at 13:59

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