Page 303 - The Secret War in the Italian front in WWI (1915-1918)

CHAPTER THIRTEEN

rules for new cIPhers desIgn and usage
The implementation of D and R codes aims also to restricting only to non-confidential
communications the several codes and ciphers proliferating within the Armies and their depending
units, often for multiple usage: in telephony, as well as for optical signalling, geo-telegraphy, and,
sometimes, radiotelegraphy.
Some of them - mostly low secrecy systems - were the likely reason why Austrian decrypting
activities continued until the last months of 1918. For example, the 3 Army introduced in early
rd
April and modified in September a Cifrario per collegamenti a mezzo di radiotelegrafia, geofonia,
eliografia e bandiere (Code for radiotelegraphy, geophony, heliography and flags), including a list
of sentences organised by sectors such as “attack and defence”, “artillery”, “losses”, “prisoners”,
etc. each with its corresponding two-letter code groups . This one-part code did not meet the
24
fundamental cryptologic requirement, not least because it had to be entirely replaced in the case of
capture. However, surprisingly it remained in use for about five months without any modification.
For these reasons, the Cryptographic Unit was induced to issue rules that all combatant units had
to follow in designing ‘home-made’ systems. After excluding paged and other codes previously
widespread among the Armies, the new regulations stated that “the match between plaintext items
and code groups must be completely arbitrary: any more or less regular sequence would hinder
the secrecy of the cipher itself” .
25
In short, the D code was the model to follow even for the number of homophones required for the
most common letters and syllables. Moreover, the words to be included in the new deliveries had
to be “chosen starting from the telegraphic texts already transmitted, dealing with subjects similar
to those foreseen for the code application” .
26
The ‘centralised control’ established for each new and old cipher spurred controversy with some
Headquarters of the Armies, which invoked the need to use simpler codes, especially for telephone
calls. The Headquarters, 3 Army argued that it was impossible to use the D and R codes, or other
rd
similar numerical codes for phonograms, and insisted on maintaining systems identical to those
described above and mainly concealed languages . The debate in this regard with the Intelligence
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Service lasted until the end of the war.

13.3 THE EFFECTIVENESS OF THE ITALIAN “RADIO INTELLIGENCE”

ausTrIan radIcal changes
As previously mentioned, in March 1918, the Austrian army officially resumed radio transmission
and repealed previous restrictive instructions, issuing new rules for correspondence and coding
applicable to wireless stations assigned to higher echelons down to Divisions.
A renewed confidence on the usefulness of radio communications based on the experiences of the
previous battles and/or the ‘push’ by the German allies may have influenced the decision to abandon

24 AUSSME, Series B4, env.521.
25 Intelligence Service, Norme per l’uso e la compilazione di cifrari (Rules for use and compilation of codes and chiphers),
Circolare, no. 45 RT, 25 luglio1818, AUSSME, Series F2, env.45.
26 This criterium was applied to the ‘Divisional Code’ based on statistical analysis conducted since early 1917 on a large set
of dispatches exchanged among Divisions.
27 Headquarters, 3 Army, Linee e comunicazioni telefoniche, (Lines and telephone communication), letter no. R.I. 2892, 26
rd
August 1918, AUSSME, Series E2, env.89.

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