Sunday, January 29, 2012

Normandy 1944 – What-if scenarios and the Fortitude deception

An interesting question that pops up on the internet is if the Germans could have defeated the Allied landings in Normandy. People like to talk about deception plans, Hitler sleeping until noon, Rommel not having command of the Panzer divisions etc etc etc .These discussions are very simplistic and come to the conclusion that if only Hitler hadn’t done x or y things would be different. They also seem to forget that apart from Normandy there were also the  Southern landings.

I think that by simply looking at the strength of German and Allied forces in Normandy on 6 June ’44 we can come to a definite conclusion regarding the outcome of that battle.

Source for the map: British intelligence in the Second World War vol3 part2
The German units as seen on the map are :
243 ID :  11,529 - 14 Marder 38 and 10 StuG III assault guns
709 ID : 12,320 - 9 7.5cm Pak 40 A/T gun on tracked chassis

716 ID : 7,771 - 10 7.5cm Pak 40 A/T gun on tracked chassis
711 ID : 7,242
352 ID : 12,734 - 14 Marder 38 and 10 StuG III assault guns
91 :  7,500
21 Pz Div : 16,297 - 112 Pz IV tanks
Also in the area was Flak–Sturm-Regiment 1 equipped with 8.8cm flak guns :  ~ 3.000
Plus various small units : ~ 7,000 plus ~80 French tanks
Total strength :  ~ 85,000
Armored vehicles : 112 Pz IV, 67 self propelled guns and ~80 obsolete French tanks. Sum: 259.

Mobile units close by  are :
12 SS : 20,516 – 164 AFV
 Pz Lehr : 14,699 – 237 AFV
However these units did not fight on the first day of the invasion.
[Source: Normandy 1944: German Military Organization, Combat Power and Organizational Effectiveness ,p28]

Now regarding Allied strength user RichTO90 has posted the hard numbers on Axis History forum.

Total strength : 150.000
Armored vehicles : 922
Those numbers are for 6 June only.
In the entire western theatre the Germans had about 2,000 tank and Stug vehicles  [Source: Panzertruppen vol 2 1943-1945 ,  Sturmgeschutz & Its Variants ].
The Germans managed to get more than 922 AFV’s to Normandy on 29 June ’44 ( accumulated AFV strength committed: 1,124),[Source: Normandy 1944: German Military Organization, Combat Power and Organizational Effectiveness  ,p414]
So what is there to discuss? I haven’t even mentioned the Allied domination of the air and the sea. There is no way that the German forces could have defeated the invasion.
Now another argument is that if the Germans hadn’t been deceived by Allied deception plans they would have concentrated their forces in Normandy and won the battle. I don’t understand that scenario. If the Germans concentrated all their forces in one place, before the invasion, the Allies would attack in another.
A smarter version of this is that the Germans could have won if they had quickly moved all their forces to Normandy, especially their mighty reserve held in the 15th Army area in anticipation of the real invasion. This ‘’reserve’’ was supposedly not used thanks to a hugely successful deception campaign. A detailed look into this affair requires a separate essay so here i will just briefly mention some facts:
All these mythical reserve forces disappear if one looks at the actual German divisions in the area. Out of the four operational mobile divisions in the West (21Pz ,12 SS , 2nd Pz , Pz Lehr) three were close to Normandy and only one near Calais ( 2nd Pz) . That unit was also ordered to Normandy on 9 June ’44.
The Flak Korps was a mobile unit with powerful armament that had four regiments. Three were in the Somme Estuary and one in Normandy. On 6 June the other three were also ordered to Normandy.
Obviously the Germans were tricked by the Allies to hold their forces back...
The mighty reserve that would have allegedly thrown the Allies to the sea was actually made of the divisions behind the northern coast of France. These were the 84, 85,326,331 and 182 divisions. The last two were not operational as they were refitting /reforming. The rest had 28,363 men. That’s not the end of the argument as the other units of 15th Army could theoretically contribute mobile groups to Normandy but I’ve never seen anyone even try to calculate if/how that could have happened. My advice to people who think that the allies won through deception is buy these books:  Normandy 1944 , D-day deception  .
Another argument is that the Germans had a million troops in the West and the Allies only landed 150.000 in Normandy so they should have won. However the total strength of the German forces on an entire continent has no meaning when we look at a specific area. Unfortunately the Germans had not yet discovered Star Trek type teleporters so they would have to find a way to move their forces from one area to the other. The only way was by foot, by truck and by rail. Military units can move simple soldiers by foot but their heavy equipment cannot move itself .German units in the West were woefully short of trucks so that option was limited ,[Source:Feeding Mars: The Role of Logistics in the German Defeat in Normandy, 1944].And for some reason the Allies thought it would be a good idea to bomb the French rail network. Strange people those Allies...
So where am i getting at? There’s no point in discussing what-if scenarios in cases when the disparity of forces is too great. The Allies won thanks to their own efforts not due to Hitler’s mistakes or Rommel’s or mystical deception plans.

Saturday, January 28, 2012


I uploaded files :

HW 40/180 ‘’PERS Z-S, the Diplomatic Decryption Bureau of the German Ministry of Foreign Affairs: reports and POW interrogations’’ ( 44 Mb , 124 pages )

HW 40/181 ‘’PERS Z-S, the Diplomatic Decryption Bureau of the German Ministry of Foreign Affairs: reports and POW interrogations’’ ( 37 Mb , 113 pages )

The following TICOM reports can be found in them :

HW 40/180 :  I-27 , I-22 , I-1

HW 40/181 : I-208 , D-78 , D-53 , I-103 , D-16 , I-63

Tuesday, January 24, 2012

Compromise of Soviet Diplomatic code – more clues ?

In this post I had a look at the possible compromise of Soviet Kod26 during WWII.

Recently I stumbled on to more information:

From ‘’The Secret History of MI6’’ by Keith Jeffery , p500 :

One early, and perhaps disturbing, result of this was the news from SIM officers in October that their cryptographic section had previously broken the 'diplomatic cyphers' of United States military attaches, the 'Russian confidential cypher', and those of Turkey , Yugoslavia, Greece, Portugal, Egypt, Brazil and Belgium. The results had been 'passed to Germans and Hungarians' who could 'now presumably decypher all above cyphers'.

SIM was the Italian Army’s Intelligence Agency – Servizio Informazioni Militari .Was the ‘’Russian Confidential Cypher’’ the Soviet diplomatic Code? How could the Italians have solved it ? They were not known for their cryptanalytic capabilities. Did they take photos of the code book and tables like in the case of the American ‘’Black’’ code ?

It just so happens I have that report from HW 40/132 ‘Decrypts relating to enemy exploitation of US State Department cyphers, with related correspondence’.

Notice that the officer who received it has marked the ‘Russian’ and requested a re-check. Perhaps  it was a mistake. Then again there are other clues.

From ‘’Deadly Illusions’’ by Costello and Tsarev , p399-400  :

Among other important items of intelligence in SENIOR'S report relayed by KENT was the possibility that the Germans would resort to unconventional forms of warfare. It also gave the precise whereabouts of the Fuehrer's headquarters on the Eastern Front and significant information about important leaks in Allied communications:

.... The Germans possess the USSR's diplomatic cypher, which was captured in Petsamo, however, the cypher has reportedly not yet yielded to the extent that there is an opportunity to decypher any large volume of Soviet documents....

This was one of the  messages  sent in November 1941 by the ‘’Senior’’ network of the Rote Kapelle , operating in Berlin.

So what can we conclude from this information ?

The Germans had captured diplomatic code 26 in the  Petsamo consulate in summer 1941 , however in order to decode messages they would need to strip the additive pads .These were only used once so the system was unbreakable.

is it possible that by having the codebook and receiving photos of the additive book from the Italians the Germans managed to decode Soviet diplomatic traffic ?

Monday, January 23, 2012


I uploaded file GERMAN ANALYSIS OF CONVERTER M-209 - POW INTERROGATIONS ,found in NARA (NR 3946 ZEMA13 15123A)

Sunday, January 22, 2012


I uploaded file CSDIC SIR 1717 - Consolidated report on information obtained from the following PW : Erdmann , Grubler , Hempel , Karrenberg , Schmitz , Suschowk in the Ticom folder  .

Saturday, January 21, 2012

German codebreakers vs Enigma

During WWII the commercial Enigma cipher machine was used by the Croat State of Ante Pavelic and the Armed forces and Diplomatic corps of Switzerland. In both cases the Germans were interested in knowing the content of the messages.

For Croatia it was the need to keep a close eye on an ally in the Balkans. Switzerland on the other hand was a neutral state but since many agents and diplomatic missions operated on Swiss soil it was only natural that the Germans would want to learn its secrets.

The Croat Enigma was used by both military and civilian authorities, so it was attacked by the  Army signals intelligence agency  Inspectorate 7/VI and  by OKW/Chi. In both cases solution rested on knowing the wiring of the rotors plus cribs (known plaintext in the cipher text).Things were easy as the Croats did not change the ringstellung often . (Ringstellung:The ring setting, the position of the rotor wiring, relative to the alphabet rings ,Source: Rijmenants, Dirk(2010) 'Enigma Message Procedures Used by the Heer,Luftwaffe and Kriegsmarine',Cryptologia)

The Swiss Enigma was harder to break as the wiring of the wheels was changed upon receiving the machines. The military traffic could not be decoded due to few messages. The diplomatic traffic however was decoded successfully by OKW/Chi and the Forschungsamt.

Let’s take a look at the available information :

Croat Enigma  :
From EASI vol4 -Army High Command Signal Intelligence Service ,p171-2
When the German government established the puppet government of Croatia in 1941, the Croats were given the commercial model of the Enigma for use by their Army and Secret Police. The traffic of these units was read by the Balkan section currently without any delay.

From TICOM I-92 ‘’Final Interrogation of Wachtmeister Otto Buggisch’’ , p2-3
2. Solution of Croat Enigma. This was not an outstanding cryptanalytic achievement. The machine used was the K model, with three wheels and no stecker. The machines were made for the Croats by the firm of KROSKY and KRUGER, Berlin, which gave the wirings promptly to OKW/WNV in about 1941 or 1942. A single key was used throughout the entire Croat Army and area, and this consisted only of a list of 100 settings for a period of a month. As far as Buggisch knew the Ringstellung stayed always at AAA, and the wheel order at 1, 2, 3. Just to make sure, the Germans paid for one of the first keys used, and with this decoded traffic were able to establish stereotypes and solve almost 100% from the first.
The solutions were done entirely by hand with wiring charts, assuming a pet beginning (one third of all messages began with "MINORS") and assuming the left hand wheels and Umkehrwalz unmoving (only one notch per wheel as in the commercial model). The Croats also had pet indicators and so would furnish depths in case this method did not work. The setting was indicated directly by a two digit number unenciphered, so that the settings wore solved almost as fast as they came, and the traffic read currently from then on. Buggisch did not recall the contents in detail. 90% of it was uninteresting; there were some interesting messages about actions against Tito
Buggisch said the Germans had considered equipping the Croats With the military Enigma, as they did for HUNGARY,  ROUMANIA , FINLAND and ITALY (and JAPAN, he thinks) in about 1942. However, they decided acainst this as they believed the corrupt CROATS would go right on selling the keys to British agents, while they, the GERMANS, would have to pay as well instead of solving free. (The possibility of a BRITISH solution obviously did not occur to Buggisch during this discussion of the K model.)

Swiss Enigma :
From EASI vol 4 -Army High Command Signal Intelligence Service , p163
80. Work on Swiss, Spanish , Portuguese ,Brazilian traffic - From 1941-1944 –the French section of In 7VI had subsections for Swiss, Spanish, Portuguese, and Brazilian traffic. As Kuehn stated, however, the volume of traffic was always extremely small and unimportant .Buggisch, one of the chief cryptanalysts of In 7/VI, worked with Kunze of the Foreign Office on the solution of the Swiss Enigma (the Commercial Enigma) although they worked out a theoretical solution of the machine, the theory was never applied at In 7/VI to Swiss traffic because the volume did not warrant the effort.Moreover, easy solution of the traffic was precluded by the fact that the Swiss did their own wiring of the Enigma wheels and changed these frequently.

This refers to the Enigma used by the Swiss army. For the diplomatic version :

From EASI vol2 – Notes on German high level cryptology and cryptanalysis ,p76 :
39. Swiss Enigma rotor wirings were solved by cribs; other Enigmas were compromised - The Swiss diplomatic Enigma ("K' type) was read regularly, probably by the Signal Intelligence Agency of the Supreme Command Armed Forces (OKW/Chi), although Dr. Huettenhain, who revealed this solution, did not state definitely that it was his agency which accomplished it. The Swiss changed their Enigma rotor wirings every three months, but the changes were not effected on the Berne-Washington link at the time they were made on the Berne-London link. As a result duplicate messages sent by the Swiss to Washington and to London during the periods of changeover provided the "break' necessary: to learn the new wirings.
The Croat enigma, used for both diplomatic and military traffic, was read regularly by Inspectorate 7/VI (In 7/VI). This was no credit to the cryptanalysts involved, however, as their problem was particularly easy:
 (1) they had obtained the rotor wirings from Konski and Krueger (Berlin) who made the rotors;
(2) there was no end-plate plugging involved;
(3) the rotor orders were not changed by the Croats;
(4) the "ringstellungen' (devices enabling the notches and alignment indicator letters to be "slid' in relation to the rotors) remained fixed; and
(5) there were only 100 initial rotor alignments used by the Croats each month.
An excellent treatise on Enigma ("K’’ type) solution was found in the files of the Foreign Office Cryptanalytic Section (Pers Z S). It involved obtaining many messages in depth, reading these messages by solving the successive (monoalphabetic) columns of superimposed text, and then applying the resultant cribs to recovering the wirings of the rotors.These methods are well-known to Anglo-American cryptanalysts.

From EASI vol7 - Goering’s Research Bureau ,p87 :
Swiss Systems.
Swiss Enigma Machine. Paetzel stated that the Swiss Enigma  was formerly broken for a while, but only when it was Improperly used. The same internal settings  were used for a long time. After the inner settings changed we did not have any more solution. At first we reconstructed  the wheels from cribs and from the fact that the inner settings remained the same. In his 1941 Report Dr Brandes of Pen ZS mentions solution of the Swiss Enigma. Apparently the FA furnished Peps ZS with a partial solution which Dr Kunze was able to complete.Thereafter there was an exchange of keys between the two agencies.

From EASI vol3 - Signal Intelligence Agency of the Supreme Command Armed Forces , p68 :
There was apparently a separate desk for Swiss traffic headed by First Lt. Kunze. Traffic enciphered on the Swiss Enigma vas regularly read. Huettenhain said that the wiring was changed every three months, but the changes at Washington were not made at the same time as those in London. Cribs thus provided by the Washington Traffic for the London traffic made it possible to solve the London wirings.

From EASI vol6 - The Foreign Office cryptanalytic section ,p32 :
Switzerland. Generally speaking, all Swiss diplomatic systems were read except the Enigma cipher machine. That, too, was read for a time in 1941. The codes were chiefly three-letter books, usually bi-lingual, enciphered with a series of substitution tables. New wirings of the Enigma were solved by cribs every three months. Subsequent messages were recovered from message texts.

The American and British codebreaking agencies also attacked the Swiss Enigma using the same methods as the Germans. It seems however that the results did not justify the effort as the content of the messages was not interesting:
By the fall of 1943, American cryptanalysts were reading Swiss Enigma traffic on the Berne-Washington circuit, and by 1945 they had general access to all circuits. The intelligence product, however, was modest. Traffic usually dealt with trade, prisoners of war, the repatriation of internees, and Swiss protection of 'enemy' interests in belligerent states. While appreciating the opportunity to monitor Swiss imports for evidence that goods were transshipped to Axis countries, American intelligence ultimately concluded that 'the intelligence value of most messages in Swiss systems is low'.

Friday, January 20, 2012


I added new information in article A who's who of German signals intelligence. Specifically the German meteorological service and the Postal Ministry.

Monday, January 16, 2012

Soviet speech scrambers

Apart from codebooks and ciphers machines the major powers of WWII also used speech privacy systems to protect their sensitive radiotelephone communications.

The American A-3 device, built by Bell Telephone Laboratories , was used for the link London-Washington. Unfortunately for the Allies it was solved by two German teams .One working for the Army Ordnance, Development and Testing Group, Signal Branch – Wa Pruef 7 and the other working for the Post Office.

The successor of A-3 was the SIGSALY device which offered absolute security. The drawback was the huge size of the equipment .According to the  NSA  website it weighed 55 tons !

The Germans used devices similar to the A-3 but did not consider them secure (for obvious reasons). Michael Pröse mentions the Siemens & Halske   ’’Kleiner Leitungsverzerrer GK III’’ [Source: Pröse dissertation ,p172] .During the war they tried to develop a secure system but did not go beyond prototypes.

The Soviet government was also concerned about the security of its voice communications. According to an article in Agentura in the late 30’s they developed a scrambling device called EU-2 which used speech inversion. A more secure system was developed by ’42, the Cobol-P. 

German Signals intelligence units in the East intercepted those radiotelephone conversations and according to Karrenberg scientists at Wa Pruef 7 were able to solve them at will  up to 1943. It seems to me that this Soviet device, which the Germans called  X, must have been the EU-2 or one of its modifications.

In 1944 however a new scrambling device was introduced which proved secure. The Germans called this X2. Again by comparing with the  Agentura article it seems they were referring to the Cobol-P. By the end of the war however their research had identified the principle of the Soviet device (time division scrambling with wobble inversion) and they may have reconstructed some conversations according to Huettenhain.

Time to take a closer look at all this information.

1). From EASI vol2 – p73,

37.Early Russian ciphony was solved by analysis of spectrograms

Radio telephone conversations between Moscow, Leningrad; Irkutsk, Alma Ata and Tcheljabinks, involving Russian Army and People's Commissariats, up until 1943, were enciphered by two simple methods which were said to be easily solvable by German engineers at  the Army Ordnance, Development and Testing Group, Signal Branch.(Wa Pruef 7), according to Corporal Karrenberg, of the Signal Intelligence Agency of the Army High Command (OKH/GdNA) .These two methods of Russian enciphering were:

a. Inversion, employing superimposed modulation of several audio frequencies; and,

b. Distortion, by artificial raising of amplitudes of speech harmonics.

German scientists were able to solve these two simple enciphering methods by recording the enciphered speech, making spectrograms from the recordings, and analyzing them .Evidently the voice engineers could see the results of the inversion and distortion, on careful inspection, and could readily identify the frequencies and methods used for encipherment. They tried it: only a few times, according to Karrenberg, but were successful at will. At the beginning of 1944, however, the simple enciphering methods were dropped by the Russians, radio telephone traffic networks themselves were changed, and no further entry was gained by the Germans. Dr. Buggisch of the Signal Intelligence Agency of the Supreme Command, Armed Forces (OKW/Chi) studied spectrograms of this later unsolved Moscow-Madrid radiophone traffic at the Army Ordnance, Development and Testing Group, Signal Branch Laboratories (Wa Pruef 7) where he became convinced that Russian ciphony then involved time scrambling, with the length of the individual time segments being 10 milliseconds each, and a  synchronizing pulse occurring every .6 second. The number of "pickup heads" used by the Russians to obtain this time, scrambling was reported in one interrogation to be three and, in another to be four. German engineers were unable to learn any more than this from the spectrograms. They could reconstruct fragments of speech, they thought, but "the validity of the solution did not satisfy Dr. Huettenhain's critical sense," when shown to him. Dr. Huettenhain, who consulted with Dr. Buggisch, believed that some form of one-time strip might have been used to key the time transposition, as he could find no: period whatever in the encipherments.

2). From EASI vol4,p44

The four independent Stationary Intercept Companies assigned to work on the eastern front had the following assignments. To Feste 11 was assigned coverage of high-frequency traffic on the Red Army and the NKVD. Originally, this Feste was located at Winniza, latterly at Kiev. The other two Feste, 7 and 8, concentrated an special Russian traffic. Feste 7 was the Russian Baudot reception station at Minsk. In 1942-43 it was moved to Loetzen where it became part of Section 4 or the HLS Ost and continued to intercept Russian Baudot traffic. Feste 8 was the former Army intercept station at Koenigsberg. After 1942, this station concentrated on Russian wireless telephone traffic called by the Germans Russian X-traffic. Attempts were made to pick up this traffic by equipment developed by Army Ordnance, Signal Equipment Testing Laboratory (Waffenpruefung, abbreviated Wa Fruef 7). The channels monitored ran east of Moscow; the traffic was mainly economic. From 1942 to 1944, this traffic was successfully recorded; but after 1944 the Russians scrambled their wireless telephone traffic, and after unsuccessful efforts to intercept this scrambled type had been made, the monitoring was dropped.

3). From TICOM I-213 ''Report on interrogation of Alfred Muche'' ,p3
Russian Systems. 
17. MUCHE himself never worked on Russian systems but he stated that they were first recorded and worked on in 1944 by a party headed by LOTZE. In February 1945 MUCHE was visited in hospital by LOTZE who told him that the Russian system had been broken and that basically it was a TIGERSTEDT system ( =TDS), with wobble inversion. MUCHE could not remember, or was never told, the number of TIGERSTEDT heads involved; he thought it might have been seven. He did not know the period of the TIGERSTEDT key, or even if it had one.

4). From I-31 ‘Detailed interrogations of Dr. Hüttenhain, formerly head of research section of OKW/Chi, at Flensburg on 18-21 June 1945’, p12

5). From TICOM I-2 ‘Interrogation of Dr. Huettenhain and Dr. Fricke at Flenshurg, 21 May 1945’, p2




Saturday, January 14, 2012

Exploding telephone poles in the Eastern front

One of the systems employed by the German forces for their telephone/teletype communications was the drehkreuz lines. When used together with frequency carrier equipment they carried a large number of voice and teletype channels.

However in the Eastern front there was a serious problem for German wire communications. The Soviet partisan movement attacked the telephone poles daily, especially in the area of Army Group Centre.

In order to protect their communications the Germans used strong points , pursuit detachments and  telephone poles filled with explosives. Once someone tried to cut them down the explosives went off.

The last measure  had the expected result but only for a while. The partisans overcame the problem by forcing villagers who lived nearby to cut the poles.

Source: Foreign Military studies : P-132  ’’Signals Communications in the East – German experiences in Russia’’ – 1954  ,p219-20 (available in the fold3 site)

Wednesday, January 11, 2012

British Air Forces in France - May 1940

In May 1940 the following RAF forces were stationed in France :

BAFF - British Air Forces in France :

 AASF - Advanced Air Striking Force: a bomber force within range of German industrial targets

 RAF component: whose mission was to provide reconnaissance and fighter cover to the British expeditionary force.

Their numerical strength (serviceable aircraft available) :

AASF :  Bombers -126

              Fighters - 28

RAF component:  Bombers - 55

                             Fighters -  57

                             Army cooperation - 76

Total : establishment - 408

            serviceable – 342

Although the numbers seem small it is actually a significant contribution from the RAF. The BAFF is 38% of serviceable RAF combat aircraft.

The problem for the RAF is that it is simply too small to fight on even terms with the Luftwaffe in the Battle of France.

Source : AIR 22/32 ‘’War Room Daily Strength Returns’’


I uploaded file RAF Strength 1939-45 ( Fighter,Bomber,Coastal Commands) in the TICOM folder .It contains pics of strength returns for said Commands for January, May and September of each year during 1939-45.

I also included Fighter Command returns for June, July and  August 1940 ( Battle of Britain).

Source is  AIR 22 ‘’Air Ministry: Periodical Returns, Intelligence Summaries and Bulletins’’

Monday, January 9, 2012

Another clue of German success with Purple ?

Looking around in my reports I noticed something interesting :
From TICOM I-64  "Answers by Wm. Buggisch of OKH/Chi to Questions sent by TICOM’’ , p3

3. Liaison with the Japanese 

Use of the "Verbindung" led B. promptly into along discussion of Jap systems in particular and diplomatic systems in general, but when we finally pinned him down to crypt relations he said he did not know about OKW--but had never heard of any-- and as for OKH he was sure that there had never been any Japs around in the flesh or any liaison he knew of. The previous discussion of systems got onto some interesting ground.
B. thinks Steinberg (of 209 fame) solved some Jap machine traffic which was difficult but not so hard as Enigma. B. thinks it was traffic of the Jap Military Attache. HUETTENHAIN told B. that the Japs were using Enigma in their traffic to TOKYO--or so B. remembers. Later he said Enigma was used almost 100% on all diplomatic links at the end of the war, and we checked him back and asked if he did not mean that the Germans used Enigma to TOKYO, not the Japs. He said he thought it was both, again from hearsay. HUETTENHAIN had al told B that the diplomatic traffic was Enigma with some element of the key, Stecker he thought, changed from message to message.

The Japanese may have been using the Enigma T but certainly not on all of their links. This version also lacked a steckerboard so Huettenhain’s alleged comment seems odd.

Is Buggisch’s testimony another clue of possible German success with the Purple cipher machine? Was that the machine that Steinberg solved? 

Thursday, January 5, 2012

WWII Myths – Weak Panzer Divisions after 1940

This myth is mentioned by Guderian, the famed Panzer General in his memoirs :

After the campaign Hitler ordered a considerable increase in the number of panzer and motorized infantry divisions. The number of panzer divisions was soon doubled, through this involved a halving of the tank strength of each division. Thus the German army, though doubling its nominal strength in armored divisions, did not acquire double the number of tanks, which was after all what counted.

Source: Panzer Leader, p138

So the idea is that in order to create more mobile divisions, quickly, the stupid Hitler ordered half the tanks to be taken from the existing units thus weakening them.

France May 1940

Number of Panzer Divisions: 10

Number of Panzer Regiments: 16 – All units have two except 6,7,8,9 Panzer divisions.

Number of tanks with Panzer Divisions: 2,582 –  258 per div

Operation Barbarossa 1941

Number of Panzer Divisions: 17

Number of Panzer Regiments :  17 – One per Division

Number of tanks with Panzer Divisions: 3,266 – 192 per div

Total AFV strength for Barbarossa was : 3,266 tanks in Pz Div plus 250 stugIII plus 135 Panzerjager I plus 340? tanks in four Panzer Abteilung =  ~ 4,000

So what happened was that indeed units lost a Panzer regiment but this did not necessarily mean that strength was affected by 50% . If we look at the compositions of the tank force the difference is even more striking.

In France tanks that are incapable of frontline service (the Pz I and Pz II) constitute 57% of the tank force.

In operation Barbarossa the same types constitute only 27%.

In summer 1941 Germany has not only more Panzer divisions than she did a year ago but they are vastly better equipped. The only downside, compared to 1940, is that each unit has 25% less tanks.


Guderian was exaggerating . Because he was a legendary soldier he gets off with a warning.

Tuesday, January 3, 2012

Last minute compromise of operation Dragoon

In summer 1944 the Western Allies invaded France. The first operation was codenamed Overlord and took place on 6 June ’44 in the Normandy area.

Operation Dragoon followed on 15th August ’44 in the South of France.

In my post on French Hagelin cipher machines , there was a statement by cryptanalyst Buggisch of the Army’s Signal Intelligence agency Inspectorate 7/VI , [Ticom I-92,p3] : ‘’ ……. Buggisch spoke especially of the successful solution of C36 in 1943, on de GAULLE traffic to CORSICA. He also said that the Southern France landings were largely given away as to date and strength of force by broken C36 traffic.’’

Buggisch was telling the truth. From HW 40/7 ‘’ German Naval Intelligence successes against Allied cyphers, prefixed by a general survey of German Sigint’’ , p29 :

In the Mediterranean area the Germans continued to derive a certain amount of information from low grade French traffic. On 11th August, 1944 a German Army B reports seen in Special Intelligence quoting a Free French signal, thought to be made in Hagelin, which gave details of the allocation of shipping space for the eminent Allied landing in Southern France. The time lag in issue was only about 10 hours, and on the basis of this B-report the German Admiral commanding South coast of France was warned on 14th August of the probability of a landing in his area in the near future .


I added some new information in article : German success with high level codes of the Big Three .

Specifically info on the Soviet Army’s OKK code and NKVD 4-figure

Sunday, January 1, 2012

Soviet 5-figure codes

The highest level code used by the Soviet military was the 5-figure codebook enciphered with Blocknot (book where each page had a random sequence of numbers, organized in numbered rows and columns).

There were two main categories of  Blocknots :

1.     The Individual in which each table of random numbers was used only once (at least that was the theory).

2.     The General in which each page of the Blocknot was valid for one day. The security of the additive sequence rested on the choice of different starting points for each message.

German success with the 5-figure code is mentioned by the following people :

1.     Huettenhain ,chief cryptanalyst of OKW/Chi

2.     Mettig , Head of In. 7/VI from November 1941 to June 1943; Second in command of OKW/Chi from December 1943 to April 1945.

3.     Lingen ,high ranking officer of Luftwaffe signals intelligence

4.     Fenner , chief at Division B of OKW/Chi (Cryptanalysis).

5.     Dettman , head of cryptanalysis  at Intercept Control Station East (HLS Ost); later head of the Russian section of Army Signal Intelligence.

6.     Marquart , cryptanalyst of Army Signal Intelligence .From 1944 head of  hand cipher research.

7.     Buggisch  ,cryptanalyst of Army Signal Intelligence (Inspectorate 7/VI)

8.     Werther , cryptanalyst of Luftwaffe signals intelligence. Expert on Soviet codes.

9.     Gerlach , probably signals officer (not clarified in the FMS report)

I’m going to write a detailed essay about all this in the future but for know I’d like to give the general details on the Soviet codes . The most detailed source is Ticom report DF-112 (available in the Ticom folder)  written by Alexis Dettmann .He calls all these code-systems ‘’operational and tactical code of the supreme command of the RKKA for army and airforce’’. Traffic was heavy during the Soviet-Finnish war and from summer ’41 onwards ( ~ 300 messages per day).

From pages 184-6 and 190-2 :

1.     Original designation unknown. Used from Aug'39 to Dec'40 .General additive mostly used. When 3 messages used same additive it was read in part, later completely.

2.     011-A .Used from Jan'41 to Oct'41.Read before capture. Captured June'41. 15%-25% read.

3.     023-A. Used from Oct'41 to Mar'42. Captured after put into use. Success when same sequence was reused .Often as many as 60 messages per day  ( 20% ) . Individual additive sometimes used incorrectly.

4.     045-A. Used from Mar'42 to Mar'43. Initially broken so fragments could be read. Then captured summer'42.Success similar to 0-23A.Increased use of one-time pad (individual blocknot) .Readability decreasing.

5.     062-A.Used from Mar'43 to Mar'44. Captured after put into use. Success similar to 0-23A.Increased use of one-time pad .Readability decreasing.

6.     091-A.Used from Mar'44 to May'45 (at least).Captured after put into use. Ever decreasing success. Rare use of general additive. Enciphered indicators.

General comments:

The continuity of success from 1939/40 to 1944 is impressive. Each successive code was broken and in addition a copy was captured, which meant that when the additive was stripped all sequences could be translated into words.

Success was achieved not only against the General pads but also against the Individual ones. According to Marquart the Russian cipher clerks reused the last pages when supplies were running low.

Was the success rate good or bad? Dettman gives no figure for the first code .For codes 2 and 3 he gives 15-25% and for 4 and 5 says similar but decreasing. The last one, 091-A, seems to have been rarely read. Most of the sources mention great success in the period 1941-Spring ’43. Mettig also mentions the solution of the 5-figure code after spring ’43 as one of the major achievements of the Army Signal Intelligence Agency. Given traffic of 300 msg per day and a percentage of 10%-20% we get 30-60 high level messages per day and 900-1.800 per month. Lingen says 1,000 were intercepted and in some cases up to 300 decoded each day during ’41-’43.Perhaps he is referring to the combined output of OKH,OKL and OKW.

For comparison’s sake the Allies considered the breaking of the Tunny teleprinter as one of their greatest cryptanalytic achievements. The success rate: ~5% from 4th quarter ’42 to 3d quarter ’44 and 8% overall. [Source: General Report on Tunny ]

Still the low percentages were tolerated since the decodes contained high level information.

However there is a general trend of diminishing results. Initially the Russians use almost exclusively General pads but in 1944/45 they use Individual pads for almost all the messages. That is not the only security measure hindering the Germans. According to Mettig in spring ’43 the traffic is ‘’split by Front’’ and external indicators are enciphered. Also it seems that initially the 5-digit groups forming the additive sequence were taken from the pad in only one way ( left to right and top to bottom) but later they could be taken in any number of ways. These difficulties forced the Germans to make extensive use of Hollerith/IBM equipment for cryptanalysis.

Both Lingen and Dettman state that cryptanalysis gave the Germans valuable information about the concentration of enemy forces. Lingen mentions specifically about the 5-figure code: ‘’They contained complete lists of losses of men and material, the combination of several scattered and virtually annihilated divisions. In them was reported the status of the troop units, supply, regroupings of units of all branches and impending actions’’. [Source: Ticom DF-292 ,p39].

The solution of the highest level Soviet code was an impressive achievement which has not been recognized by historians.

Did the Soviet authorities learn of the German success? Was that the reason for the increased use of Individual pads? Or was the use of General pads an anomaly caused by problems in printing and distributing the Individual pads during the war?

Another more interesting question is what success (if any) did the Russian codebreakers have with German high level codes? So far there is no information of possible cryptanalytic success with the Enigma and the cipher teleprinters.

A more detailed essay will follow with information from a large number of Ticom reports.
Update: More information on the Soviet military’s enciphered 5-figure code is available in Compromise of Soviet codes in WWII.