Page 217 - The Secret War in the Italian front in WWI (1915-1918)

CHAPTER TEN

to other more sophisticated
procedures .
38
In his book, Andreas Figl
does not explicitly say that
the Austro-Hungarian army
used ciphers derived from the
Vigenère table during WWI:
yet he affirms that in that period
those systems were considered
reliable by the armed forces of
several countries because “they
guaranteed sufficient security
although under specific
circumstances”, therefore
“their application can seem
admissible still today” .
39
It should be noted that
in operational situations
occurring on the front-
line during combat, the
conditions Figl alludes to,
such as the application of
above-mentioned methods
in manipulating the Bolton
Chiffrenrad with disordered
alphabets or even the frequent
change of long keys, could
only happen under favourable
circumstances.
10.5 Austro-Hungarian encoding and decoding disk used during WWI
(from F. Sinagra book)

38 For example, the Kerckhoffs method can be applied to all poly-alphabetic systems with a short key. Sacco also describes
other more complex decrypting systems (ibidem, p. 172 – 185).
39 A. Figl, Systeme des., op. cit, p.84. The Author presents an example “adopted for subordinate units and that started being
used in the 1890s”.

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