General der Nachrichtenaufklärung Training Referat (Nachrichten Dolmetscher Ersatz und Ausbildings Abteiling) was the training organization within the General der Nachrichtenaufklärung (GDNA), the military signals intelligence agency of the Wehrmacht during World War II. Initially established from May 1941, it continued teaching until September 1944. Until 1942, the work of the Training Referat was not fully exploited and only a small beginners course was taught.
Training operations During World War II, the Oberkommando der Wehrmacht suffered from an acute shortage of cryptanalyst personnel, and it was found that the practice of pushing forward groups of cryptanalysts to key areas behind the front, did not of itself provide adequate signals intelligence, particularly as the front lines were getting further away from Berlin.
As a result, Commanders of forward intercept units were allowed to create their own cryptanalysts teams. Two difficulties were encountered in this connection; firstly, a lack of technical knowledge, and secondly the entry into the cryptographic service of personal who were untrustworthy from the security point of view. In two cases in KONA 2 in Smolensk personnel were unearthed who were guilty of espionage. As a result of this a security vetting for all security, translators and cryptanalysis personnel was introduced.
Once the forward cryptanalysis units had been set up, and eventually became the Long Range Intelligence Company (NAZ), they were attached to various Close Range Intelligence Company (NAK) which coordinated intelligence and forwarded the raw flow of intercepts into the Signal Intelligence Evaluation Centre (NAAS). It was agreed to allot the NAZ units investigation of forward lines of communication traffic which could be solved in the field. In 7/VI remained, however, responsible for all army cryptanalysis work and concentrated on the most difficult and unsolved procedures.
As a personnel establishment for these forward cryptanalysis units, it was found necessary to have two or three linguists and one to three mathematicians. Such personnel were trained at a six weeks' course by In 7/VI. 200 cryptanalysts were trained successfully and included such individuals as Major Dr Hentze, Lieutenant () Lüders and Lieutenant Schubert. The results of this work in 1941 and 1942 was to enable In 7/VI to concentrate on research into more difficult procedures.
Training classification
Training of signal recruits The Signal Intelligence Replacement and Training Battalion () was located in Frankfurt, was responsible for the training of German Army Signal recruits. It had control over Signal Intelligence Replacement and Training Companies in each Service Command District () where basic training and some training in signal matters were given to the recruits.IF-250, Page 2 In time of peace, basic training lasted one year, signal training being taken up after the first three months. During the war, the time of basic training was shortened in order to place more troops more quickly in the field. Recruits were trained in direction-finding, teletype operation, and simple field codes, and they were sent out into field units.IF-250, p. 3 No special courses were conducted in the Replacement and Training Companies.
Training of signal technicians Most of the signal technicians were trained in specialist academies of various sorts. Academies for carrier frequency, switchboard operators, repair men, etc., were established by the Army and Division and Corps Signal Battalions and at Army Signal Depots. Instructors were mainly non-commissioned officers who had experience in the field.
Training of specialists The Signal Interpreter Replacement and Training Battalion () was relocated in Saint-Avold in March 1944 and relocating back to a garrison in Halle in 1944. This battalion was responsible for the training of signals interpreters who were to be employed in signal intercept units for radio and wireless monitoring. The battalion was divided into three companies: company one was for Romance languages, company two for Slavic languages, and company three for training of Germanic languages. For matters of administration, the battalion was divided into the following 5 platoons:
Cadre platoon () comprising cadre personnel and instructors in military and intelligence technical matters. Instructor platoon () comprising teachers and members of the instructor group. Training platoon ()comprising the students who were under instructions in some language. Alert platoon () comprising men who have passed their final examination and who are expecting to be sent into action. Pool () comprising newcomers waiting for their entrance examination.
A rough estimate of the personnel shows that in 1944, there were about 350 to 400 men attending the various languages classes. After the courses which lasted 6 weeks, the men were given a final examination. According to the results of this examination, they were assigned to one of the three following categories:I-96
{| class="wikitable" |+ Courses by categories |- ! Personnel categories ! Comment |- | S – Speakers () | These were people who spoke well and were able to make themselves understood, but who did not master the language in speaking and writing correctly. |- | U – Translators () | These were people who mastered the foreign language in writing, but were only fair in speaking. |- | D – Interpreters () | These were people who spoke and wrote the foreign language correctly and fluently and whose general education was up to a corresponding standard.
Employment was assigned according to the category to which each person was assigned.
For persons of category S, a special course in monitoring Allied radio communication was organised at Leipzig for English speaking personnel only. The course consisted of three weeks daily instruction in the following subjects:
USA and British organisation of signal units. USA and British radio sets used at all levels. USA and British radio call signs. USA and British authorized abbreviations. USA and British message forms. USA and British fixed station and net operational methods. USA and British Army terminology.
Each of the subjects was taught for one hour a day and had a brief examination. In most cases, the lectures were conducted in English to facilitate practice in this language.
Training of signals officers The Army Signal Academy located in Halle () conducted the course for officer candidates of the Signal Corps.IF-205, p. 5 Emphasis here was in the first months evenly divided between technical and military subjects. The officer candidates were selected by their commanders in the field after having proved themselves in combat or in outstanding work in their specialty. All enlisted men were eligible, although the racial origin evidently played some part in the selection. One prisoner, for instance, states that he was not allowed to become an officer candidate, because of his Jewish grandmother.IF-127, p. 1
After their selection, the men were given a four weeks course in tactics, Army regulations, customs, technical subjects. Those who passed this preliminary course were sent to the Armed Forces Signal Troop Academy () where they were trained for three months in Signal Corps work.IF-250, p. 6 From there they were sent into the field for a probation period as leaders of platoons. During this period of training, Colonel Grube states, many of the candidates lost their lives. A final three months at the Signal Academy in Halle brought, with graduation, the rank of Leutnant (second lieutenant).
Training of cryptanalysts Nothing is known of the training of Army cryptanalysts before 1939. Major Mettig, the commander in charge of cryptanalysis unit, stated while in interrogation after the war, that when the KONA regiments moved into the field in 1939, no cryptanalysts were available to decipher enemy codes and ciphers. Colonel Kunibert Randewig, the commander at that time of all traffic intercept, or listening stations in the west, however, was able to procure a number of cryptanalysts from the Feste around Berlin, and to this force he added a few mathematicians and linguists. As a result, when the German offensive began in April 1940, the KONA units had a moderate supply of cryptographic personnel. The early war years clearly showed that additional personnel were needed. A Training Section in In 7/Vi was established under the leadership of Kuehn, but Mettig stated that the work in the unit was not fully exploited until 1942. The Training Section was located at Matthäikirchplatz 4 in Berlin until November 1943, when it was moved with the rest of the Agency to Jüterbog because of the Allied bombings. In November 1944, the Training Section 7 of In 7/VI became Referat 5 of Group IV of the GDNA. The training academy consisted of about 20 officers with 120 men, and about 12 women who worked as stenographers.IF-127, p. 2
The course, which lasted 10–12 weeks ran during the morning and for two to three afternoons per week. Instruction was verbal and by blackboard. A brief history of cryptography was studied from a syllabus, and included a general picture of the methods of encipherment, details of various means of encipherment and decipherment. During the remaining afternoons, the students evidently specialized in whatever field to which they were to be assigned. One prisoner of war, Gerd Coeler, stated that during the afternoons, he studied English military terms and abbreviations, including the history and organisation of the British Empire and the geography of England. Corporal KarrenbergI-166 outlines the course given for those who were specializing in Russian cryptanalysis. Participants were selected from the personnel of the Signal Interpreter Replacement and Training Battalion, that understood the Russian language. After the most capable interpreters had been selected they were given a course in Russian cryptography, which included all types of Russian systems. For practice in this course actual Soviet military intercepts were used, to gradually accustom the men to Soviet field problems.
The German Army Cryptography Course The course consisted of the following:
Substitutions methods A simple substitution, or more accurately a mono-alphabetic substitution ciphers is a generalisation of the Caesar cipher where there can be any permutation of the alphabet. For the simple substitution cipher there are 26! possible keys, which is huge, but even then, the cipher insecure.
After methods of solution were demonstrated on the blackboard, each student was given practice problems, based on clear English text, to solve for themself. The SKYO machine, syllabic codes and code books were also dealt with at this stage. Of these, the British War Office Code was treated in greater detail and based on this, students were explained the general methods of breaking the recipher and the methods to reconstructing a code book.
A A clear symbol, e.g. letter, figure, syllable, word, is replaced by a cipher symbol
Simple substitution with standard alphabet a) Alphabetic simple polyalphabetic cipher
{| class="wikitable" |+ Simple Alphabetic |- ! scope="col" | Method? ! scope="col" | Result |- !colspan=1 style="text-align: left; background:LightSteelBlue" |Clear alphabet |style="text-align: left;" |ABCDE...... |- !colspan=1 style="text-align: left; background:LightSteelBlue" |Cipher alphabet |style="text-align: left;"|DEFGH......
Example of enciphering;-
{| class="wikitable" |+ Results |- ! scope="col" | Method? ! scope="col" | Result |- !colspan=1 style="text-align: left; background:LightSteelBlue" |Clear |style="text-align: left;"|BAD DAY.. |- !colspan=1 style="text-align: left; background:LightSteelBlue" |Cipher |style="text-align: left;"|EDC CD...
b) Simple substitution cipher with standard alphabet
{| class="wikitable" |+ Standard Alphabet |- ! scope="col" | Method?