Page 210 - The Secret War in the Italian front in WWI (1915-1918)

THE SECRET WAR ON THE ITALIAN FRONT IN WWI (1915 – 1918)

recovery operations . However, the
14
KOD was still used by submarines
even after September 1916 .
15
To understand the structure the KOD
series, reference can be made to the
fourth version (KODVIER) entered
service in 1918, with a first page
indicating 1916 as the year of the
earliest book printing (picture 10.1).
Therefore, subsequent versions were
developed by adding and replacing
items in the original version .
16
The KOD comprises approximately
300 pages and 25,000 terms. It is
paged, as Red and Mengarini codes,
adopting code groups of five figures:
three of them represent the page
number, two figures between 00 and
99 identify words or figures on each
page. Alternatively, the code groups
can be made up of pronounceable
words of ten letters, with six of
them corresponding to the page and
four to the word on each page. The
pronounceable word is assembled 10.1 First page of Austro-Hungarian navy’s KODVIER
by adding to the part of the word
reported at the bottom of the page (see picture 10.2), four letters included in a single table that
converts the two-figured numbers corresponding to the terms on every page. For instance, the code
group that corresponds to the word “Abhang” (slope) in picture 10.2, can be 48220 or alternatively
“caccialeon” if the word “leon” corresponds to number 20 in the conversion table . This table
17
varies from a version of the code to the next one or more frequently.
From the type of key sent by Sacco to the Italian navy, one can infer that the radio telegrams in
question were encrypted with groups of five figures to which the number 39842 was added or
subtracted (‘additive’ key).
When the Austrians changed the numerical key, Lieutenant Pellerani, serving at the Navy
Headquarters of the Venice area, referred to the Cryptographic Unit “for the analysis of the results

14 Nikolaus Sifferlinger: Le intercettazioni radio austro - ungariche e inglesi nel Mediterraneo durante la Prima Guerra
Mondiale, in “La Guerra Navale 1914 - 1818”, editors A. Rastelli e A. Massignani, G. Rossato, Ed., Novale, Valdagno, 2002.
p. 160 e s. The author of the article referred to documents in the English archives describing, amongst other things, the codes
the Italians recovered from the wreck of the U24 submarine.
15 In case the KODEIN had been used, Sacco had also identified the changes made to the second edition of the code.
16 The Austro-Hungarian navy released several versions of the code up to the sixth (KODSECHS), by using different over-
encoding methods (J. Pricowitsch, op. cit., p.453).
17 The article by N. Sifferlinger mentioned in a previous note explains that this ciphering method was called ‘46’. During the
war, the Austrian navy used other methods by breaking up the five basic figures in a different manner (e.g.: 1+2+2) and then
by over-encoding each group with groups of letters to obtain words of ten letters. In addition, the KODEIN differs from the
basic version KOD mainly due to the inversion of numbering in the left-side column on each page (99 to 50 instead of 50 to
99) and to the changed page numbering.

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