Page 215 - The Secret War in the Italian front in WWI (1915-1918)

CHAPTER TEN

The information that can be inferred from the report shows that when allowed to communicate
via radio, in particular Austrian small stations and combat units used code and ciphers of
different types, even extremely simple ones . Some of those are described in the next pages
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based on the appendices of Section R’s report and on other sources.
Only in few cases, a clear indication of the usage time frame is given for codes and chiphers
shown in the document. An attempt to identify the relevant periods for some of the remaining
ones will be carried aut thanks to the contents of radio decrypted telegrams shown, as
examples, in the report.

square Tables and cIPher dIscs

Sacco’s notebook includes several references to Austrian substitution-based ciphers, both
mono-alphabetic and poly-alphabetic. Line 2 of the list written in August of 1916 mentions
a key alphabetical cipher of the Austrian army, evidently a substitution cipher because the
word ‘transposition’, generally added in that case, is missing.
On the other hand, the abovementioned communication to the Allies explains: “various types
of codes and square tables (used by the Austrians A/N) are well known. A square table with
an alphabets number ranging from one to thirty is used with keys”. The table shown in the
document looks like a Vigenère table, with 30 lines and 30 columns, where ä, ö, ű and the
question mark are added to the 26-letter alphabet (see picture 10.4).
The report also comprises a specimen of Austrian cryptogram ciphered by the same 30x30
table and decrypted by identifying the key, which was the word hoesterreich, with the first
“h” omitted on purpose in the first position of the sequence. The dispatch is shown in Annex
B (picture B1).
In brief, there is no doubt that the Austrian Army, for a long time during the war, had been
using this kind of ciphers, initially mono-alphabetic, then poly-alphabet with short keys,
remarkably like the Pocket Military Cipher, which had been so harshly criticized.
Such encoding can also be obtained through disks or rulers adequately designed . Since
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the beginning of the war the Austrian army extensively exploited, across several levels of
command, encoding and decoding disks designed after the one Leon Battista Alberti had
created four centuries earlier and which they called Bolton Chiffrenrad or Zirkularscheiben.
These were in metal, but also in cardboard or paper with ordered or disordered alphabets .
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A disk with ordered alphabets on both rims did not guarantee any further secrecy in comparison
to a regular Vigenère table, especially when used with short keys. Messages coded by a disk
where one of the alphabets is disordered, as it is the metal disk shown in picture 10.5, result
more difficult to decrypt . This disk has the external rim divided into 30 parts, including a
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disordered alphabet with the letters ä, ö and ű, while the same alphabet but in the orderly form
is stamped on the internal mobile rim. The disordered alphabet allows to generate a group

33 On the other hand, J. Prikowitsch, (op.cit. p.406 – 418) also describes some bulky, usually two-part Codebücher that were
presumably used by High Commands, perhaps rarely for radiocommunications. In the Codebücher identified by Roman
numerals from XV a XVIII, the ciphering groups comprise 5 figures. In the category, identified by Greek letters from Gamma
to Lambda, the code groups were made up of letters from the Latin alphabet, which amounted to 8 in the last Lambda edition
(September 1918). Finally, F, G, and M are two-part codes with code groups of 5 figures.
34 With a chipher disk, the encoding is performed, for instance, by rotating the inner disk until the key letter coincides with
a fixed reference and by reading the ciphered letter on the outer rim that corresponds to the plaintext letter on the inner disk.
35 J. Pricowitsch, op. cit. p.422, 431.
36 The disk was shown of a temporary exhibition at the War Museum of Mauthen, Carinthia. The Author is indebted with
Filippo Sinagra for the photography.

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