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Military and intelligence history mostly dealing with World War II.

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    I added information in the Jellyfish article. Specifically the reasons for changing the landing sites for the airborne operation on D-day and the effect of the daily change of internal settings for the SZ42 on Bletchley Park’s operations.

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  • 10/23/12--00:36: US Military Strip Ciphers
  • The US Armed forces made extensive use of the strip ciphers M-94 and M-138 in the 1930’s and during WWII. Although authors focus on the SIGABA machine initially only a handful of these were available.  In late 1941 there were around 10.000 M-94 devices, 1.500 M-138 strips and 120 SIGABA. It would take years to build large numbers of cipher machines and during that time it was the strip ciphers that had to hold the line.

    Overall about 10.000 M-94 cylinders and 17.000 M-138 strip ciphers were built from the 1920’s till 1944.

    The strip ciphers have gotten little publicity but their use was vital for the US forces in WWII, especially in the period 1941-43. The M-94 cylinder was used at division level and was eventually replaced by the M-209 cipher machine. The M-138 (and M-138-A) was used for high level messages by military units and diplomatic attaches. During the war it was replaced by SIGABA but It continued to be available as an emergency system till the 1960’s.

    The M-94 cylinder

    US reports refer to M-94 as a cylinder cipher while the Germans called it strip, same as the M-138. The cryptographic principle was identical for both systems.

    The M-94 was composed of a central spindle on which 25 cylindrical alphabet wheels were inserted. The daily key specified the order of inserting the wheels. Then the user spelled out the message on one line by turning the wheels and chose the cipher text from another line.

    The inventors of the cylinder cipher were Thomas Jefferson, Commandant Etienne Bazeries of the French Army, Captain Parker Hitt, USA and Major Joseph Mauborgne, USA.

    The M-94 was officially adopted in 1921 and used till 1943 when it was replaced by the M-209 cipher machine. It was undoubtedly a system of limited security but the official history SRH-366 says: ‘It is very easy for us to condemn old devices in the light of later knowledge, and the M-94 looks childishly simple to us now, but let nobody underestimate the good purpose that it did serve at a period when something better than the old Cipher Disk and Playfair were badly needed.

    The same report says that about 10.000 M-94 devices were procured from 1921 to 1941.

    The M-94 was used extensively in the interwar period. The Navy version was called CSP-488. In 1929/30 it was issued to military and naval attachés. In 1939 units of the Coast-Guard received it. US Army and Army Airforce units used it extensively in the period 1941-43. In 1943 it was declared obsolete.

    The M-138 strip cipher

    The same cryptographic principle was used by a flat strip device utilizing alphabet paper strips. This consisted of an aluminum frame (or later wooden/plastic) with room for 25 or 30 paper strips. Each strip had a random alphabet. The daily key specified the strips to be inserted and the order that they were to be inserted in.

    The plaintext was written vertically at the first column by rearranging the strips. Then another column was selected to provide the ciphertext.

    Compared to the M-94 the M-138 had the advantage that paper strips were much easier to construct and use than the metal cylinders.

    The first flat strip system adopted by the US Army was the M-138 in 1934. It used 25 paper strips. The positions for the paper strips were called ‘channels’.

    It was soon replaced by the M-138-A which was a 30 channel system. The first major procurement took place in 1940 with an order for 550 devices. Mass production began in 1942 and the lack of aluminum forced the authorities to use panels built out of plastic and wood. These were given the code designations CSP-845 for plastic and SIGWOWO for wood. The plastic version did not prove satisfactory because heat caused the warping of the panel. The wooden version also proved problematic due to friction of the paper strips on the board. The procurement numbers were 5.000 for CSP-845 and 2.000 for SIGWOWO.

    In September 1943 the aluminum shortage was overcome and production of the aluminum version was resumed. Immediately 8.000 were ordered. This order made it possible to recall all plastic and wooden versions.

    Total production from 1935 till 1944 was for over 17.000 units.

    Civilian authorities like the State Department, the Office of Strategic Services, the Treasury Department, the Manhattan Project and others used the M-138-A.

    The strip system was also shared with foreign allies such as Brazil, Canada, Costa Rica, France, UK, Italy, Philippines and the USSR.

    Security of strip ciphers

    The security of the strip ciphers is summarized in SRH-366: ‘The cryptographic strength of the disk or strip cipher lies in the variable factors which it provides, namely, encipherment by a number of different, sliding, mixed alphabets and a possibility of 25 different letters for each letter of plain text. The cryptographic weakness of the strip or disk cipher is the constancy of the interval between the letters of any one plain-text alignment and the letters of its cipher text generatrix ; it is this inherent characteristic which serves as the wedge for all cryptanalytic recovery of this type of system. All security improvements of the device itself and of methods of using it have been designed to prevent cryptanalytic establishment of this constant factor.

    The standard security measures for the M-138-A system were the change of the strips every couple of months and the daily use of 30 strips out a larger number (50-100 depending on the link).

    From 1939 50-100 alphabet strips were supplied to each user. Out of these 30 were chosen each day.

    Initially there were only 50 available rearrangements for the strips. This meant that during the period of use some days would have the same strip ‘key’. This was changed from August ’42 when a different arrangement was provided for each day.

    From 1939 till mid 1942 the alphabet strips were generally replaced after six months. From January ‘42 a change every quarter and later bimonthly was instituted. By August ’43 the strips were changed each month. This important change was first introduced in many systems in August ’42.

    Message length was limited to 100 5-letter groups.

    During the war these measures were not enough and two important security procedures were adopted.

    Split generatrix

    The standard procedure was for the user to arrange the strips so that the plaintext message is written in the first column. Then another column is selected as the ciphertext (generatrix). This was changed by having the user select a different cipher column for the first 15 letters and another one for the next 15.

    This procedure was used for CONFIDENTIAL messages from January ‘42 till July ‘43 when channel elimination was adopted for both CONFIDENTIAL and SECRET messages.

    Channel elimination

    The M-138-A had 30 positions in the panel for the paper strips. These panel positions were called channels. In order to increase security 5 of these channels were kept empty. A different set of strips were removed for each message, based on an elimination table. The table specified which of the 30 channels in the panel would be empty.

    The procedure broke up repetitions in the cipher text. From January ’42 it was required for all SECRET messages.

    It was first introduced in some army networks in 1939 and until early 1942 only one elimination table was provided for each network. From January to August 1942 the same channel elimination table was in effect for three months, same as the strips. From August ’42 both the channel elimination table and the strips were changed monthly.

    As a result of security studies in September ’44 a new variable elimination procedure was adopted. The new system allowed for up to 5 channels (not necessarily 5) to be eliminated each time.

    German exploitation of US strip ciphers

    M-94 cylinder

    The Germans intercepted US traffic enciphered with the M-94 and solved the system cryptanalytically.

    The German Army’s signal intelligence agency OKH/In 7/VI created a USA section when the US entered the war against the Axis. Head of the department was Dr Steinberg a member of the mathematical research department. Initially the main effort was to identify the US wireless networks, the call signs and the cipher systems used. The main cipher system used by the Americans at that time was the M-94 cylinder.

    The 25 alphabet wheels were supposed to be used in a different order each day but some links used them in the same order for longer periods of time. Dr Steinberg and dr Luzius solved the system by using IBM/Hollerith equipment to find repeats. These always occurred on a distance of 25. According to Luzius: ‘having identified 20 to 30 passages of cypher text as being in depth, they could then solve each column as a simple substitution, and in this they were considerably assisted by stereotyped openings. They solved most of the traffic on this system, but he thought that the contents were generally relatively unimportant. As instances of its use, he quoted meteorological traffic from Greenland and Air Force traffic in the Caribbean’.

    Ironically they found instructions for the M-94 in a Berlin library after they solved it cryptanalytically.

    From spring ’42 traffic from the US to Africa, Ireland, Britain, Caribbean area, Iceland and Greenland was read. Mettig, head of the Army agency in 1941-43, says that in 1942 the contents had to do with transfers and promotions.

    The USAAF Northern route ferry traffic (indicator URSAL) was also exploited by the Luftwaffe’s Chi Stelle from summer ’42 till December 1943.

    M-138 strip cipher

    A US strip system used in the Pacific area in 1942 (indicator DUPYH) was received from the Japanese and read for a year by the German Navy’s B-Dienst. TICOM report I-197 states that it was read thanks to the compromise of the strips and the ‘eliminator tables’, which would make it a flat strip system.

    A USAAF M-138 link was solved by Voegele, chief cryptanalyst of the Luftwaffe in the West.

    The USAAF Southern Route ferry traffic strip system with indicator CENEB was read from November ’42 till 1943 when channel elimination was employed.  This strip originally used the split generatrix system. From ‘European Axis Signal Intelligence in World War II’ vol2:

    According to Dr. Ferdinand Voegele, Chief Section B, of the Signal intelligence Agency of the Air Force High Command (OKL/LN abt 350), a strip cipher of the United States Army Air Force South Atlantic Ferry Command was solved before 1943. He wrote:

    ‘It was quite evident from the cipher text that there was a break after each 15 letters.... Accordingly an analysis was made on the basis of groups of 15 letters with the assistance of I. B. M. machines. A depth of 80 passages of parallel construction was needed to reconstruct the 100 strips, 30 of which were valid in any one day.... The system was read as long as it was used. In 1943 a new difficulty presented itself. While 30 strips were still valid on any one day the encipherer could arbitrarily remove any five of the strips to encipher any one message... . After-about six weeks; some of these messages were also deciphered. However, at the same time the volume of this type of traffic began to decline so that finally the analysis work had to be discontinued.’

    Techniques employed by Voegele and his assistants are not known. Decipherment by about six weeks of some of the later messages, when strip elimination was employed, may have been accomplished by the skilful use of cribs. It is interesting to note that soon after strip elimination had been introduced, ‘the analysis work had to be discontinued’.

    This report makes it seem like Voegele is making excuses when he says that the traffic declined considerably. The truth is that the traffic was actually reduced. The Brits had become aware through Enigma decrypts that this traffic was intercepted and forwarded to Berlin so they naturally assumed that it was being exploited currently. They notified the Americans so that the strips were changed and some of the traffic was sent through an RAF system.


    The Germans had more success with the M-138-A used by the State Department.

    Sources: SRH-366 ‘History of Army Strip Cipher devices’, TICOM reports I-12, I-76, I-78, I-112, I-113, I-119, I-127, I-154, I-197, I-211, ‘European Axis Signal Intelligence in World War II’ volumes 1,2,4,5  , ‘The Achievements of the Signal Security Agency (SSA) in World War II’, ‘German analysis of converter M-209 - POW interrogations’, ZIP/D-S/G.9 ‘Enemy success with US strip ciphers’,  Wikipedia (for the strip pics)

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    This short but very interesting book covers the USAAF strategic bombing effort in WWII. The author looks into the beginnings of strategic bombing in WWI, the interwar theories and the history and performance of the US Army Airforce bombers in the European and Pacific theatres.

    There are separate chapters for the planes used, the bombs, the bombsights, the aircrews, the campaigns and the postwar bombing surveys.

    The author is highly critical of the theory and practice of strategic bombing in WWII. The interwar bombing theories of Douhet, Mitchell and Trenchard were superficially attractive to politicians and military officers. Instead of sending hundreds of thousands of young soldiers to fight in the trenches a country could invest in a large bomber force that could quickly attack the enemy’s population and industrial centers. According to the prophets of airpower these attacks would lead to the collapse of the enemy’s economy and mass panic would force the government to surrender. These theories were based on the principles that:

    1). The bombers would always get through to their targets.

    2). The bombers would have no difficulty in locating and bombing the targets.

    3). The civilian population would be predisposed to mass hysteria in the event of bombing.

    In WWII these preconceptions were proven false. The use of radar meant that the course of bombers could be correctly estimated and fighters vectored to meet them, it proved to be extremely difficult to locate ground targets and the civilians of the Axis countries continued to work despite the bombing campaigns.

    Undoubtedly the promoters of airpower must have realized these problems but they were more interested in ensuring that their airforces would rise to become a separate branch of the armed forces.

    The greatest part of the book deals with the USAAF effort and looks into the equipment and personnel used. The strategic bombers were the B-17, B-24 and B-29.

    The author is not afraid to criticize icons of US airpower. The B-17 was developed in the early ‘30’s and by the 1940’s was lacking in terms of performance. The RAF found it ‘uneconomical in relation to the crew and technical maintenance required’. It could not carry the bomb load of newer models and its bomb bay could not carry large bombs used against hardened targets.

    The B-24 was a new aircraft but its ‘Davis wing’ was a source of problems. On the one hand it provided low drag at cruising speed and did not compromise high speed performance. However above 20.000 feet it was prone to high speed stalls and its design made it practically impossible to successfully ditch the plane in case of an emergency .

    The B-29 was the most expensive bomber produced by the US. However its problems in the field were legendary. Eventually more were lost to accidents than by enemy action.

    These planes were supposed to be able to defend themselves through heavy defensive armament and close formation flying. Over Europe the German fighter defenses inflicted heavy casualties and thus fighter escort was required. This role was performed by the P-47, P-38 and P-51 fighters. The P-47 was a very heavy plane, affecting its acceleration and climb rate. However at high altitude it was a good performer. The twin engined P-38 performed well in the Pacific but in Europe it had serious engine problems at high altitude. Eventually the fighter that would change the airwar would be the P-51 due to its unprecedented range and its excellent flying performance.

    Bombing targets from 20-30.000 feet using unguided bombs was, to put it mildly, slightly inaccurate. The chances of the bombs dropping close to the target were minuscule (according to a USAAF study ~1.2% for a single B-17 flying at 20.000 feet to hit a factory sized target). This reality was compounded in Western Europe by the cloudy weather that made precision bombing impossible most days. Highly developed bombsights like the US Norden proved to be useless in W.Europe because of the clouds and smoke. In response to this problem the British H2S radar sight was used but its accuracy was even lower than the optical types.

    Under these conditions locating targets was very difficult and accurately bombing them almost impossible. The USAAF compensated by using large numbers of bombers in every mission so that some would hit the target. However the cost of building and operating such forces was huge.

    The human cost of the bombing campaign was also very expensive. Bomber crews had little chances to survive their 25 missions (increased in 1944). In the first half of 1944 the casualty rate was 89%. Casualties finally went down in the second half of ’44 when the Luftwaffe could not effectively attack the bomber groups due to attrition and lack of fuel.

    At the end of the war the USAAF organized a detailed study of the German and Japanese economies and the effects that strategic bombing had on them. Famous economists, like Galbraith, were part of the teams that did the analysis. The results showed that German war production increased during the war despite the bomber offensive. In fact the year that production peaked was 1944 despite the huge Anglo-American effort. The separate RAF study came to similar conclusions.

    Galbraith was critical of the US bombing survey and wrote in ‘A Life in Our Times’: ‘But strategic bombing had not won the war. At most it had eased somewhat the task of the ground troops who did. The aircraft, manpower and bombs used in the campaign had cost the American economy far more in output than they had cost Germany. However our economy being much larger we could afford it.’

    Overall this is a very interesting and outspoken analysis of the USAAF strategic bombing effort in WWII.

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    The site Master of Homeland Security has posted the 100 best sites on national security. This weblog is included in the list as number 15. Not bad for an amateur historian like myself!

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  • 11/01/12--02:05: Update
  • I added information on Emile Bollaert, Pierre Brossolette and Forest Yeo-Thomas in German counterintelligence operations in occupied France.

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    During WWII Sweden was neutral but maintained close economic relations with Germany. The German signal intelligence agencies were interested in Swedish communications and they tried to solve their diplomatic and military systems.

    The Swedish diplomatic traffic was mainly enciphered with Hagelin cipher machines. The Germans analyzed the traffic but according to postwar reports could not solve it (although one message of 5.000 words may have been solved).

    The military traffic was intercepted and decoded successfully by a unit in Halden, Norway. This was outstation Halden (Aussenstelle Halden). This unit belonged to Feste 9 (Feste Nachrichten Aufklärungsstelle -Stationary Intercept Company) but was attached to the Halden Police battalion for administrative purposes. It was commanded by Lieutenant Thielcke.

    The systems solved by the Germans were:

    1). SC2 - Slidextype system, read in May ’43.

    2). SC3 - 3-letter field code without reciphering, read in April ’43.

    3). SC4 - 3-letter alphabetical code without reciphering, read in June ’43.

    4). SRA1 and SRA5 - Grille/Stencil systems. First broken in the spring or summer of ’43.

    5). SM-1 (Schwedische Maschine 1) - version of the Hagelin C-38. This was solved on operator mistakes and ‘depths’. Some details are given by Luzius, an expert on Hagelin cipher machines at the German army’s signal intelligence agency:
    7. He was then asked whether they had achieved any other successes with this type of machine. He recalled that the Hagelin had been used by the Swedes, in a form known as BC-38. This was similar to the M-209, but with the additional security feature that, whereas with the American machine in the zero position A = Z, B = Y, etc., In the Swedish machine the relationship between these alphabets could be changed. He could not remember whether it had changed daily or for each message. He himself had worked on this machine and had solved a few messages. It had been an unimportant sideline, and he could not remember details; he thought that it had been done by the same method, when two messages occurred with the same indicators. This had only happened very rarely.

    The people of Aussenstelle Halden were not successful with all the Swedish codes. According to ‘European Axis signals intelligence’ vol4 the high level grille HCA and the ‘large’ Hagelin (probably a version of the Hagelin B-211) were not solved.

    The solution of the tactical codes and the C-38 allowed the Germans to build up the Swedish army’s OOB. Why were the Germans so interested in the army’s dispositions? It seems that in 1943 they contemplated an attack on Sweden.

    Sources: European Axis signals intelligence’ vol4, CSDIC/CMF/Y 40 - 'First Detailed Interrogation Report on Barthel Thomas’, TICOM reports I-55, I-64, I-211, ‘Hitler’s war’

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    During WWII the radio traffic of Soviet units was one of the most reliable sources of information for the German Command. Through traffic analysis and D/F the numbers and location of units could be identified. In cases where the messages themselves could be decoded the Germans could anticipate enemy attacks.

    In the first years of the war in the East the Germans could read practically all the Soviet codes. In the period 1943-45 however the SU upgraded its cryptologic security. The top level 5-figure code was enciphered almost exclusively with one time pad and the insecure 4-figure codes of the OKK type were replaced with SUV tables.

    This meant that the work of the Germans codebreakers became much harder. However they were helped in their work by a serious error in the Soviet Union’s radio security. Special units controlled by the Soviet High Command (assault, engineers, artillery, supply) did not follow the strict protocols of the standard military formations nor did they use secure codes. These errors allowed the Germans to circumvent the new Soviet procedures.

    By monitoring the traffic of the GHQ units assigned to large Soviet formations their concentrations and movements could be followed.



    Source: FMS P-038 ‘German radio Intelligence’

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  • 11/09/12--03:52: Update
  • Added information on the Christie suspension and made some corrections in WWII Myths - T-34 Best Tank of the war.

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    In my piece on the compromise of OSS codes during WWII it was stated that Allen Dulles occasionally used diplomatic ciphers when his own systems where overloaded.

    In 1943 the Germans were apparently able to read his messages enciphered on the M-138-A strip cipher. The question is whether this was an OSS strip set or the special set used by the embassy in Berne for diplomatic traffic.

    Report SRH-366 ‘History of Army Strip Cipher devices’ says that the Army Signal Intelligence agency provided M-138 strips for OSS use in 1944.

    This would mean that the system exploited by the Germans in 1943 was probably the diplomatic strip.

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  • 11/16/12--01:00: Update
  • Added information and made some changes in A who’s who of German signals intelligence.

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    As I’ve mentioned before the internal Soviet radioteletype network was intercepted during the 1930’s and 1940’s by the Germans and postwar by the Americans.

    The intercepted plaintext traffic concerned economic and military matters and was of vital importance in finding out what was happening inside the Soviet Union.

    However the Russian Fish intelligence was definitely a case of quantity over quality. This is clearly mentioned in several TICOM reports and matches the American assessment during the early cold war period.

    Alexis Dettmann, head of cryptanalysis at the German Army’s cryptanalytic centre in the East -Horchleitstelle Ost, says in TICOM DF-112:

    The monitoring and deciphering of internal radio traffic was not an assignment of army signal intelligence units but necessarily messages of internal networks were solved and worked on. Special offices in the former German army were occupied among other things with the reception of messages of Baudot circuits, the value of the results however belonged in a different sector. Even in the years 1938/39 a relatively simple devise was constructed which made it possible to reproduce directly on typewriters the Baudot messages which in part ware transmitted by high-speed transmitters. The results from the point of view of content in no wise corresponded to the expectations. Of the entire traffic monitored at great expense at best 10% was useful for economic leaders while military-political matters constituted hardly 1%.. The major portion of these messages was like the content of the long distance telephone messages and contained private or business affairs. It was learned that all these circuits were not only monitored and controlled by the NKVD but in many cases were directed by it, and that in all probability the GUP-NKVD was also responsible in large measure for the issue of cryptographic material for internal radio traffic.’

    Otto Buggisch, a member of the cipher machine department of the German army’s signal intelligence agency, gives the same percentage in TICOM I-58:

    Further on Russian Baudot – B. says that one Dipl. Ing. Gramberg came to group IV with him from In 7/VI (Army Signal Intelligence) and was used to translate the intercepted clear text in Russian Baudot. ‘’ 90% of it was unimportant’’.

    The relative lack of importance of each individual message was also recognized by the Americans. According to NSA history ‘The Invisible Cryptologists: African-Americans, WWII to 1956’:

    ‘The ASA. effort to exploit Russian plaintext traffic began in 1946 with the part-time assignment of several linguists to the target. At that time, however, the Agency's emphasis was on the translation of encrypted messages, and the employment of scarce Russian linguists on plain text was judged to be unwarranted. Later, in May 1947, the effort was revised at the Pentagon. Individuals without security clearances or with partial clearances would sift through volumes of messages and translate all or parts of those determined to have intelligence value. Placed in charge of this group was Jacob Gurin, an ASA Russian linguist who had immigrated to the U.S. with his parents at the age of three.


    From the Agency's inception under William Friedman, its business was the breaking of codes and ciphers. Once the underlying text was revealed, individual messages were translated, and, after a reporting mission was established, selected ones were published on 3" x 5" cards. While individual decrypted messages could be extremely valuable, plaintext messages were most often preformatted status reports that were insignificant when considered singly. Jack Gurin was convinced that if these messages were assembled and analyzed in the aggregate, they could yield valuable information on Soviet defense capabilities.


    For both the Germans and Americans the limited value of single messages was leveraged by the huge intercept volumes.

    FMS P-038 ‘German Radio intelligence’ says: ‘At the experimental station the volume of recordings, which were made available to the cryptanalysis and evaluation sections of the Armed Forces Cryptographic Branch and the Evaluation Control Center of OKH, averaged ten million transmissions a day.

    Information on the  Anglo-American interception is available in NSA history ‘On Watch: Profiles from the National Security Agency’s past 40 years’:

    In addition to manual Morse, the Soviets were using a good deal of [redacted] among others. The Soviet plaintext problem was a SIGINT success story from the beginning, from the design of electro-mechanical processing equipment that could handle each new Soviet development to the painstaking analysis of the intercepted communications. A joint American-British effort against these communications in the nineteen-forties led to high intercept volume and new engineering challenges in the face of proliferating Soviet [redacted] techniques.

    At one time the United States and Britain together were processing as many as two million plaintext messages a month, messages containing everything from money orders to birthday greetings. The production task was awesome, with analysts manually leafing through mountains of page copy, meticulously screening millions of messages. [redacted] The investment paid off, leading, to an encyclopedic knowledge of what was going on in the Soviet Union. Over 95 percent of what the United States knew about Soviet weaponry in the nineteen-forties came from analysis of plaintext radioprinter traffic. Almost everything American policy makers learned about the Soviet nuclear energy and nuclear weapons programs came from [redacted] radioprinter traffic, the result of fitting together thousands of tiny, selected pieces of the jig saw puzzle.’


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  • 11/20/12--01:22: Update

  • Added Stein, Hasenjaeger, Aumann, Weber, Witt, Schultze and Grunsky in German mathematicians in the cryptologic service.

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    The wireless transmission of imageswas used by WWII participants for military purposes and by their news agencies. However radio-fax communications could be intercepted…

    During WWII the Soviet Union had several radio-facsimile stations. Their transmissions were intercepted by the German signal intelligence agencies OKH/GdNA Group VI and Wa Pruef 7/IV. According to postwar reports they contained ‘hand-written communications, typewritten texts, drawings, and weather maps’ and ‘technical diagrams and charts’.

    This wasn’t the last time that radio-fax communications of communist countries were compromised. According to Matthew M. Aid’s ‘The secret sentry’, p142 after the USS Pueblo was captured by the North Koreans in 1968 a USAF listening post in Japan intercepted its top secret documents being transmitted on the Pyongyang-Moscow radio-facsimile link.

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    There is a file at NARA called SOVIET UNION, SURVEY OF THE RECORDS OF THE BAND I (NR 3708 CBTM13 20293A 19420201).

    It is a German estimate of Soviet industrial production in 1942. I assume that some of the information on this report comes from monitoring the internal radio and radio-teletype traffic between industrial centers.

    It would be interesting to compare the data on this report (and others like it) with the ‘official’ numbers from Soviet/Russian sources. Unfortunately I could only copy the first pages of this large report (~300 pages):


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  • 11/28/12--02:25: New hacking scandal

  • It seems that the Americans were able to hack into the French President’s office. Oh mon dieu!

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    In the 1930’s the main goal of the communist regime in the Soviet Union was the rapid industrialization of the country. New factories were built all over the country and farmers were brought in to work in them. The need for specialized labor also attracted some foreign engineers who were facing unemployment in their own countries due to the Great Depression.

    A small group of foreigners who immigrated to the Soviet Union during that period were the ‘true believers’ in communism.

    One of them was John Scott, son of radical economist Scott Nearing. Scott left the United States, that was at that time trapped in the Great Depression, and went to the Magnitogorsk area of the Urals in 1932.

    Magnitogorsk had huge metal deposits and factories were built to exploit those resources. The communist regime was sparing no expense in importing the best foreign machinery and in attracting experienced engineers from abroad. Scott was able to participate in the industrialization of an agricultural society and in his memoirs he gives the reader a very clear view of what it was like to live and work in the Soviet Union of the 1930’s.

    The everyday life was brutal. Accommodations were poor, fuel and food lacking and the work was very dangerous with people being injured or killed every day. The main problem was the lack of trained personnel. All the workers were peasants who had left their villages in search of a better life as factory workers. Some were hostile to the communist regime but the majority was happy to have left the fields and they spent their limited free time learning to read and write. Those who had already mastered the basics studied engineering.

    Progress was hampered by the purges of the 1930’s and the search for imaginary spies and counterrevolutionaries.

    An interesting aspect of the book is the analysis of the industrial centers in the Urals. According to Scott the decision to invest huge sums in the Ural industries had primarily a military character since they would be safe from invaders.  He calls these centers in Nizhny Tagil, Sverdlovsk, Chelyabinsk, Magnitogorsk, Perm, Ufa, Zlatoust, Berezniki, Solikamsk, Bashkortostan, Orsk and other areas  ‘Stalin’s Ural stronghold’.

    Overall this is a unique book in the sense that the writer participated in one of the greatest social and economic experiments of the 20th century. Since the book was written in 1942, at a time when the Soviet Union was still in danger of military defeat, one wonders if the analysis of the Ural stronghold was meant to inform Anglo-American policy makers of the Soviet Union’s economic power and resilience.

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  • 12/02/12--23:30: Update
  • Time for some new TICOM reports:

    I-54 ‘Second interrogation of five members of the RLM/Forschungsamt’ - 1945

    I-82 ‘POW Interrogation report Dr Werner Liebknecht of Wa Pruef 7 of the Heereswaffenamt’ - 1945

    I-100 ‘Report by Uffz. Herzfeld of NAAST 5 (Gen. d. NA) on the Work of the Italian Referat of In 7/VI’ - 1945

    I-212 ‘Interrogation of George Ruckheim’ - 1949

    Available from my Google docs and Scribd accounts.

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  • 12/06/12--02:51: Typex operational procedures
  • A file in HW 40/89 ‘Investigation into POW reports that German Sigint authorities exploited TYPEX (British cypher machine)’ has details on the use of the Typex cipher machine.

    Specifically the introduction of new rotors, detachable rotor cores (called inserts) and the rewirable reflector (called plugboard in the report):

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  • 12/09/12--02:51: Update
  • I added a lot of new information in WWII Myths - T-34 Best Tank of the war.

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    At the start of WWII and for most of the conflict the standard crypto system used by the British for high level messages was the codebook enciphered with subtractor tables. Both the Foreign Office and the military services relied on these Cyphers for their most important traffic.

    The War Office Cypher was the Army’s universal high-grade codebook (4-figure) and carried traffic between Whitehall, Commands, Armies, Corps and, later, divisions. There were different sets of enciphering tables for each geographic area (Home Forces, Middle East, etc)

    The Germans captured two copies of the WOC in 1940. One during the Norway campaign and the other near Dunkirk. The compromise of the code allowed them to focus only on stripping the cipher sequence. This was achieved by taking advantage of ‘depths’ (messages enciphered with the same numeric sequence).

    From early 1941 the German Army’s signal intelligence service was able to read messages from the Middle East theatre. A considerable number of messages were read during the Cyrenaica offensive of General Wavell. In the summer of ’41 Tobruk was encircled by Rommel’s forces and had to rely strictly on radio communications. Since the WOC was used many of the messages could be read. In late ’41 a message from Tobruk indicated that their Typex machine was in need of repairs.

    During 1941 the WOC decodes provided intelligence on the enemy’s strength, OOB and movement of units in the M.E. Theatre. For example an Enigma message decoded by Bletchley Park in October ’41 gave a summary of the increase in British ground strength in Egypt and the tank strength estimate was so accurate that the War Office was very concerned.

    The British knew that the WOC was in enemy hands and could be exploited but they had no alternative than to keep using it. Security was upgraded in late ’41 and from early ’42 the German success was hindered but not eliminated.

    The Germans continued to read some WOC traffic till summer ’42, when the intercept company NFAK 621 was captured in N.Africa. The files of that unit revealed to the Brits that many of their systems were compromised and they immediately took action to change them. From then on the WOC-ME would be secure.

    This was not the end of the German solution. According to Herzfeld, an army cryptanalyst, the WOC used by Home Forces in Britain was solved in 1943. Some traffic of January and February ’43 was read but success ended in March.  It was at this time that the subtractor tables were replaced by the new stencil cipher which proved to be unbreakable.

    Overall the solution of the War Office Cypher in the M.E. Theatre in 1941-42 was an important achievement for the German side and a serious defeat for the British.

    Sources: ‘Intelligence and strategy: selected essays’, ‘British intelligence in the Second World War’ vol2,  TICOM reports I-51, I-113, IF-107, CSDIC SIR 1704-The organization and history of the Cryptologic service within the German Army’, CSDIC/CMF/Y 40-'First Detailed Interrogation Report on Barthel Thomas’, ‘European Axis Signal Intelligence in World War II’ vol1 and 4, , Cryptologia article: ‘Brigadier John Tiltman: One of Britain’s finest cryptologists’

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