Page 321 - The Secret War in the Italian front in WWI (1915-1918)

CHAPTER FOURTEEN

with arranging it. The logs of Section U of the Intelligence Service confirmed the inter-allied code
was distributed in March 1918 .
16
Sacco was proud abut the commission received to create the I.A. code. In referring to the alleged
reorganisation of the Italian Encoding Service by the Allies claimed by Gylden, he stated that the
collaboration of the Italian Cryptographic Unit with the French and the British had been “strictly
limited to the exchange of enemy keys, except for the drafting of the inter-allied code, which we
took care of” .
17
The I.A. - a two-part code with three-letter code groups, which could be grouped in pairs in
telegrams -was changed frequently, as required to prevent breaking attempts. For instance, in June,

the Chief Inspector of the STM requested Section R to create a new inter-allied radiotelegraphic
code in three languages to replace the one in service , and about a month later, two allied liaison
18
officers, one French and one British, visited Section R “to agree on some changes to the I.A.
code” .
19
I.A. resisted to cryptanalysis, as proved by the lack of mentions by Austrian sources and by its
inclusion the among the unbroken Italian cryptographic systems, according to the statements made
by Austrian analysts captured at the end of the war .
20

hIgh coMMands codes

The new editions of the Blue and Special codes, announced in July 1918, did not see the light
during or after the conflict, since replaced by the SI code for the communication among High
Commands, with later addition of the Grey Tables.
However, the old codes were finally and completely dismissed only on 5 October, at the same time
of the new Grey Tables official adoption, as per written order of the Chief Inspector of the STM,
where he established that:

NO radiotelegraphic stations shall accept radio-telegrams to be transmitted with a 5-digit
encoding that carry the indications ‘Special’, ‘Blue’, ‘Green’. Of the telegrams with 5-digit
group encoding, only those fully encoded with the indication ‘GREY’ can be accepted and
transmitted by radio stations without further encoding .
21
After the events described in the previous chapters, which led to the creation of the new SI at
the beginning of 1918, the latter was gradually adopted outside the correspondents with the
Intelligence Service . The prior availability of the SI code down to the Infantry and Cavalry
22
Division Headquarters allowed the distribution of the new Grey Tables to all the units included in
the address list shown in picture 14.3.

16 Section U logss, 14 March 1918, AUSSME, Series B1, 101 D, Vol.360d.
17 L. Sacco, Manuale, op. cit. p. 309.
18 Chief Inspector STM, Logs, 14 June 1918, AUSSME, Series B1, 105S, Vol.91.
19 Section R logs, 23 July 1918, AUSSME, Series B1, 101 S, Vol. 321d. The two officers were the French Captain Plattard
and the British Lieutenant Fleure.
20 Intelligence Service, Attività dei Reparti crittografici, op. cit. Actually, in one of the sheets with pencil notes probably taken
by Ronge himself and kept together with his memoirs, the annotation C.I.A appears. It probably referred to the inter-allied
code, but its bare mention does not imply the code had been broken.
21 Chief Inspector STM Logs, Service Order no.29, October 2, 1918, Telegrammi da trasmettere per radio (Radio Telegrams
to be transmitted by radio), AUSSME, Series B1, 105 S, Vol. 92.
22 Based on the logs of Sections R and U of the Intelligence Service, the changes to the SI code occurred on 5 April, 23 May,
and June 1918, while in September the grey tables were distributed.

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