Misplaced Pages

#145854

75-569: K37 may refer to: K-37 cipher machine ; see Otto Buggisch HMS  Veronica  (K37) , a corvette of the Royal Navy Junkers K 37 , a German mail plane Piano Concerto No. 1 (Mozart) , by Wolfgang Amadeus Mozart Potassium-37 , an isotope of potassium Rio Grande class K-37 , an American steam locomotive Tōfutsu Station , in Hokkaido, Japan [REDACTED] Topics referred to by

150-468: A solution while sitting idle in a French port. The solution was, in fact, childish and consisted of nothing more than a study of the theoretical working equation of the machine. Jaeckle had talked his way into the SKL and had talked a lot about getting a section of 200 men to work on the machine. Actually he had been exposed quickly and had been sent back to sea after three or four months. Buggisch considered this

225-537: A 10 letter crib . The work remained purely theoretical as no traffic from this machine was ever received. In November 1941, Buggisch was transferred to In 7/VI in Berlin, working at the French specialist section, located at Matthekirchplatz 4. Posted there until August 1942, he worked on a variety of problems, including The unit included Dr Kunze of Pers Z S , working on French diagonal write-out transposition ciphers used by

300-560: A clue as to the routes. A variation of the route cipher was the Union Route Cipher, used by Union forces during the American Civil War . This worked much like an ordinary route cipher, but transposed whole words instead of individual letters. Because this would leave certain highly sensitive words exposed, such words would first be concealed by code . The cipher clerk may also add entire null words, which were often chosen to make

375-456: A columnar transposition where the read-out is by rows instead of columns. Columnar transposition continued to be used for serious purposes as a component of more complex ciphers at least into the 1950s. A single columnar transposition could be attacked by guessing possible column lengths, writing the message out in its columns (but in the wrong order, as the key is not yet known), and then looking for possible anagrams . Thus to make it stronger,

450-468: A cryptographic device constructed by Eric Tigerstedt . In Autumn, Buggisch's attachment to WA Pruef 7 was suspended, and he was transferred from AgN/NA to OKW/Chi Chi IV Analytical Cryptography (German: Analytical cryptanalysis ). This move was specifically designed to enable him to attend the Chi conference in Berlin at the instigation of Major General Wilhelm Gimmler , (German: Chef Ag WNV ). Gimmler

525-407: A cylinder of the same diameter as the encrypting cylinder. Using the same example as before, if the cylinder has a radius such that only three letters can fit around its circumference, the cipherer writes out: In this example, the cylinder is running horizontally and the ribbon is wrapped around vertically. Hence, the cipherer then reads off: In a route cipher, the plaintext is first written out in

600-413: A double transposition was often used. This is simply a columnar transposition applied twice. The same key can be used for both transpositions, or two different keys can be used. In the following example, we use the keys JANEAUSTEN and AEROPLANES to encrypt the following plaintext: " Transposition ciphers scramble letters like puzzle pieces to create an indecipherable arrangement." The colors show how

675-612: A grid of given dimensions, then read off in a pattern given in the key. For example, using the same plaintext that we used for rail fence : The key might specify "spiral inwards, clockwise, starting from the top right". That would give a cipher text of: Route ciphers have many more keys than a rail fence. In fact, for messages of reasonable length, the number of possible keys is potentially too great to be enumerated even by modern machinery. However, not all keys are equally good. Badly chosen routes will leave excessive chunks of plaintext, or text simply reversed, and this will give cryptanalysts

750-483: A keystring of "432143." Plaintext columns with unique numbers are transcribed downward; those with recurring numbers are transcribed left to right: A disrupted transposition cipher further complicates the transposition pattern with irregular filling of the rows of the matrix, i.e. with some spaces intentionally left blank (or blackened out like in the Rasterschlüssel 44 ), or filled later with either another part of

825-735: A mathematical dissertation titled On the Rarity of Equations with Affect (German: Über die Seltenheit der Gleichungen mit Affekt) which was supervised by Udo Wegner at the Technische Universität Darmstadt . During the war, Buggisch held the military rank of a sergeant in group 7/VI at OKW/Chi. From May 1940 to July 40, Buggisch was posted to a Wireless Telegraphy (abbr. W/T) Listening Interpretation Station (colloquially Out-Station or Intercept station) of Army Group C in Bad Schwalbach , Bad Kreuznach , Saarbrücken . Buggisch

SECTION 10

#1732905184146

900-407: A mechanical system of producing a transposition cipher used by the ancient Greeks . The system consisted of a cylinder and a ribbon that was wrapped around the cylinder. The message to be encrypted was written on the coiled ribbon. The letters of the original message would be rearranged when the ribbon was uncoiled from the cylinder. However, the message was easily decrypted when the ribbon recoiled on

975-587: A periodic adder, or subtractor of length 11. In the other, it was ordinary transposition, the transposition key being obtained from a key word which itself was taken from the code and shown by an indicator group. Both systems were being read from the winter of 1939 to the end of the Battle of France in June 1940. Buggisch also worked on analysing the diagonal write-out transposition ( Transposition cipher ), C-36 cipher machine These were simple field codes. From 20 July 1940, he

1050-411: A permutation cipher) is a method of encryption which scrambles the positions of characters ( transposition ) without changing the characters themselves. Transposition ciphers reorder units of plaintext (typically characters or groups of characters) according to a regular system to produce a ciphertext which is a permutation of the plaintext. They differ from substitution ciphers , which do not change

1125-402: A sequence of "5,2,1,4,3,6" and cross out the 5th field of the matrix, then count again and cross out the second field, etc. The following example would be a matrix set up for columnar transposition with the columnar key "CRYPTO" and filled with crossed out fields according to the disruption key "SECRET" (marked with an asterisk), whereafter the message "we are discovered, flee at once" is placed in

1200-576: A transposition cipher. These include: The third method was developed in 1878 by mathematician Edward S. Holden and New-York Tribune journalists John R. G. Hassard and William M. Grosvenor who managed to deciphere telegrams between the Democratic Party and their operatives in the Southern states during the 1876 presidential election and thus prove facts of vote buying , influencing the 1878-1879 congressional elections . A detailed description of

1275-636: A very foolish incident altogether. In the first two months of 1944, Buggisch conducted discussions with colleagues on cypher problems and the teleprinter T43, which was the new secure model first discussed in spring 1943 while he was staying in Köthen During the first half of 1944, he conducted research into the weaknesses of the Naval Emergency Key along with Kapitän zur See, Captain at sea Beegemann and Fregattenkapitän Frigate captain Singer. He studied

1350-518: Is different from Wikidata All article disambiguation pages All disambiguation pages Otto Buggisch Buggisch graduated from the Ludwig-Georgs Gymnasium (LGG) in Darmstadt in 1928. He studied pure mathematics and physics and the subsidiary subject applied mathematics at the Technische Universität Darmstadt . In 1938, Buggisch was promoted to Dr. rer. nat. with

1425-414: Is often combined with other techniques such as evaluation methods. For example, a simple substitution cipher combined with a columnar transposition avoids the weakness of both. Replacing high frequency ciphertext symbols with high frequency plaintext letters does not reveal chunks of plaintext because of the transposition. Anagramming the transposition does not work because of the substitution. The technique

1500-412: Is particularly powerful if combined with fractionation (see below). A disadvantage is that such ciphers are considerably more laborious and error prone than simpler ciphers. Transposition is particularly effective when employed with fractionation – that is, a preliminary stage that divides each plaintext symbol into two or more ciphertext symbols. For example, the plaintext alphabet could be written out in

1575-458: Is read off columnwise to give the ciphertext: If multiple messages of exactly the same length are encrypted using the same keys, they can be anagrammed simultaneously. This can lead to both recovery of the messages, and to recovery of the keys (so that every other message sent with those keys can be read). During World War I , the German military used a double columnar transposition cipher, changing

SECTION 20

#1732905184146

1650-561: The Enigma Uhr device. Another device which was created to increase the security of Enigma was the Lückenfüllerwalze , or gap-filling wheel, that was built by Fritz Menzer . This was a device for varying turnover of wheels by means of adjustable plugs on the perimeter. The effort to improve the Enigma was a result of the implications of what was known Der Fall Wicher or Case Wicher . This

1725-829: The Ludwig-Georgs-Gymnasium , the preparatory course for foreign students in Darmstadt (1966–1969), and finally as a postgraduate student at the Mathematics Institute of the TH-Darmstadt (1969–1972). Immediately after the war, he was interviewed extensively by the interrogators of the Target Intelligence Committee (TICOM) regarding his work. A large part of the available information about him and his activity comes from these interrogations. These investigations were originally classified as TOP SECRET, but with

1800-565: The Wehrmacht . The B211 code was worked on with Denffer and Hilburg later in the summer. Buggisch worked in the section until August 1942, until a reorganization of the specialist desks of Section VI was undertaken. A few mathematicians left for Section IV of Inspectorate 7. Buggisch transferred to the newly formed cipher machine specialists section, conducting extensive investigations into Cipher Machine 41 (German: Schlüsselgerät 41 ). Buggisch subsequently worked on call sign 's and research into

1875-498: The Army Enigma, looking for weaknesses in that system. He examined the machine, and specifically looked for compromise of the key through message settings and looked at the question of the possibility in principle of breaking cyphers by means of statistical analysis on enormous amounts of machinery to drive During this period Buggisch's team conducted research into the field-rewirable reflector, (German: Umkehrwalze D ) which lead to

1950-743: The Croatian Enigma. From about August 1943, Buggisch worked on a captured specimen of converter 209 from Italy. During the course of 1943, the Inspectorate 7/VI was renamed to the Signal Intelligence Section of the Department of signals of the General Army Office (German: Amtsgruppe Nachrichten/Nachrichten Aufklaerun ). In October 1943, the office moved to Jüterbog . In the winter of 1943, Buggisch worked with Doering, whose specialty

2025-701: The M40 device, designed by Fritz Menzer , finding it moderately secure but it was never actually used. The M40 device was the forerunner of the Cipher Machine 41 (German: Schlüsselgerät 41 ), but the motion of the wheels was found to be not so irregular. During September 1940, Buggisch was transferred to a Soviet (Russian) specialist section. They worked on a 4-figure code ( Olowo ) and 5-figure codes, creating practice messages. In October or November 1940, Buggisch transferred to an intercept station in France. In January 1941, he

2100-666: The Old Realgymnasium Darmstadt (1938) and at the Stefan George Gymnasium in Bingen (1938–39). In May 1939, he was first called to the pioneers . Although not a member of the Nazi party, in 1943, he was appointed as a secondary school teacher (German:Studienrat) [possibly to teach the children of Nazi officials] that was held during his military service. In April 1946 he was released from prison. From 1948 to 1966, he taught at

2175-430: The best manual ciphers known". The Rail Fence cipher is a form of transposition cipher that gets its name from the way in which it is encoded. In the rail fence cipher, the plaintext is written downward and diagonally on successive "rails" of an imaginary fence, then moves up when it gets to the bottom. The message is then read off in rows. For example, using three "rails" and a message of 'WE ARE DISCOVERED FLEE AT ONCE',

2250-541: The chair at these conferences. Four different subjects were covered, with a day allotted to each. These were: Buggisch attended only the first session. In January 1945, Buggisch conducted three lectures, on ciphony, at the OKW/Chi. This was followed by a visit to the town of Ebermannstadt , and the Feuerstein Castle laboratory, to become acquainted with the proposed German ciphony systems. Buggisch worked to determine

2325-449: The ciphertext humorous. In the middle of the 17th century, Samuel Morland introduced an early form of columnar transposition. It was further developed much later, becoming very popular in the later 19th century and 20th century, with French military, Japanese diplomats and Soviet spies all using the principle. In a columnar transposition, the message is written out in rows of a fixed length, and then read out again column by column, and

K37 - Misplaced Pages Continue

2400-493: The columns are chosen in some scrambled order. Both the width of the rows and the permutation of the columns are usually defined by a keyword. For example, the keyword ZEBRAS is of length 6 (so the rows are of length 6), and the permutation is defined by the alphabetical order of the letters in the keyword. In this case, the order would be "6 3 2 4 1 5". In a regular columnar transposition cipher, any spare spaces are filled with nulls; in an irregular columnar transposition cipher,

2475-536: The cryptanalysis of a German transposition cipher can be found in chapter 7 of Herbert Yardley's "The American Black Chamber." A cipher used by the Zodiac Killer , called "Z-340", organized into triangular sections with substitution of 63 different symbols for the letters and diagonal "knight move" transposition, remained unsolved for over 51 years, until an international team of private citizens cracked it on December 5, 2020, using specialized software. Transposition

2550-497: The de Gaulle delegation in Senegal . At the beginning of 1942, Buggisch's signals unit was disbanded and he was transferred to a company called 4 Company, Evaluation Company was formed with Major Mettig in command In the summer of 1942, Buggisch was working with Doering on the first detailed investigation of cypher teleprinters , the T52 models T52a to c, that were to be extensively used by

2625-460: The decoding of the work being done by means of the method developed earlier by Denffer. It was discovered to be transposed . Likewise more B-211 messages appeared but the theoretically worked out procedure did not result in a decode. During the summer of 1943, Buggisch works with Luzius and Rudolf Kochendörffer on the Crib problem with converter 209 ( M-209 ), which had been captured from Italy. This

2700-542: The double Playfair . In November 1942, Buggisch started work into research of Cipher Machine 39 (German: Schlüsselgerät 39 ) that was being proposed for use by the Kriegsmarine . By the summer of 1942, Buggisch had been assigned to work full-time on the cypher teleprinter T52 with Doering. Buggisch and Doering worked on versions a, b, c of the teleprinter, as well as the SZ40 rotor stream cipher machine. The B-211 code

2775-748: The double transposition cipher was used by Dutch Resistance groups, the French Maquis and the British Special Operations Executive (SOE), which was in charge of managing underground activities in Europe. It was also used by agents of the American Office of Strategic Services and as an emergency cipher for the German Army and Navy. Until the invention of the VIC cipher , double transposition

2850-477: The encipherment process can render the entire ciphertext meaningless. However, given the right conditions - long messages (e.g., over 100–200 letters), unpredictable contents, unique keys per message, strong transposition methods, and so on - guessing the right words could be computationally impossible without further information. In their book on codebreaking historical ciphers, Elonka Dunin and Klaus Schmeh describe double columnar transposition (see below) as "one of

2925-419: The encrypter writes out: Then reads off: (The cipher has broken this ciphertext up into blocks of five to help avoid errors. This is a common technique used to make the cipher more easily readable. The spacing is not related to spaces in the plaintext and so does not carry any information about the plaintext.) The rail fence cipher follows a pattern similar to that of the scytale , (pronounced "SKIT-uhl-ee")

3000-569: The first few months of World War One. Since transposition does not affect the frequency of individual symbols, simple transposition can be easily detected by the cryptanalyst by doing a frequency count. If the ciphertext exhibits a frequency distribution very similar to plaintext, it is most likely a transposition. In general, transposition methods are vulnerable to anagramming —sliding pieces of ciphertext around, then looking for sections that look like anagrams of words in English or whatever language

3075-410: The grid, and the ciphertext is written down the columns of the grid in the order given by the letters of the key. The plaintext appears on the rows. A partial decipherment of the above ciphertext, after writing in the first column: In a variation, the message is blocked into segments that are the key length long and to each segment the same permutation (given by the key) is applied. This is equivalent to

K37 - Misplaced Pages Continue

3150-503: The higher and highest Soviet Army command. Soon after the beginning of Operation Barbarossa , several copies of the code were captured along with their recypher tables but with most of them out of date by that point, with the Soviets changing them frequently, but not yet daily. Owing to the already mentioned special characteristic of the first three elements of the code groups it was particularly easy to line them up. In this way, depth of 8–12

3225-508: The keys infrequently. The system was regularly solved by the French, naming it Übchi, who were typically able to quickly find the keys once they'd intercepted a number of messages of the same length, which generally took only a few days. However, the French success became widely known and, after a publication in Le Matin , the Germans changed to a new system on 18 November 1914. During World War II,

3300-463: The leftover spaces. The resulting ciphertext (the columns read according to the transposition key) is "WCEEO ERET RIVFC EODN SELE ADA". Another form of transposition cipher uses grilles , or physical masks with cut-outs. This can produce a highly irregular transposition over the period specified by the size of the grille, but requires the correspondents to keep a physical key secret. Grilles were first proposed in 1550, and were still in military use for

3375-439: The letters are scrambled in each transposition step. While a single step only causes a minor rearrangement, the second step leads to a significant scrambling effect if the last row of the grid is incomplete. As an example, we can take the result of the irregular columnar transposition in the previous section, and perform a second encryption with a different keyword, STRIPE , which gives the permutation "564231": As before, this

3450-415: The message. The ciphertext is then read off as: In the irregular case, the columns are not completed by nulls: This results in the following ciphertext: To decipher it, the recipient has to work out the shape of the enciphering grid by dividing the message length by the key length to find the number of rows in the grid. The length of the grid's last line is given by the remainder. The key is written above

3525-597: The newly formed Signals Recce Abteilung (abbr. Signals), with all personnel who worked in In 7/VI being subordinated into that unit. The Russian cipher specialist section was again subordinated to the Intercept station, with the unit moving to Loetzen . Between July 1941 and November 1941, while at Loetzen, Buggisch worked on 5-figure material, specifically the OK40 code and the K37 machine. The OK40

3600-439: The newly formed machine specialist section. Buggisch conducted an investigation into Cypher Device 41 known as Schlüsselgerät 41 . Buggisch stated that Device 41 was Fritz Menzer's idea, and the technical side was worked on by Wa Pruef 7/IV . Buggisch also worked on Call signs and weaknesses in the double Playfair cipher. In November 1942, Buggisch began research into the security of the naval version of Cypher Device 41. In

3675-479: The passing of time they can now be viewed publicly. Otto Buggisch wrote homework , specifically a report for TICOM that described in detail, the Schlüsselgerät 39 device and the use of Hollerith and other specialist machinery in the solution of Hagelin traffic. Otto Buggisch is mentioned in the following TICOM documents: Transposition cipher In cryptography , a transposition cipher (also known as

3750-409: The plaintext because there are many combinations of letters and words. By contrast, someone with the key could reconstruct the message easily: In practice, a message this short and with a predictable keyword would be broken almost immediately with cryptanalysis techniques . Transposition ciphers have several vulnerabilities (see the section on "Detection and cryptanalysis" below), and small mistakes in

3825-492: The plaintext or random letters. This method (attributed to Gen. Luigi Sacco ) starts a new row once the plaintext reaches a column whose key number is equal to the current row number. This produces irregular row lengths. For example, The columns are then taken off as per regular columnar transposition: TPRPN, KISAA, CHAIT, NBERT, EMATO, etc. Another simple option would be to use a password that places blanks according to its number sequence. E.g. "SECRET" would be decoded to

SECTION 50

#1732905184146

3900-563: The plaintext was written in, and solving the anagrams. Once such anagrams have been found, they reveal information about the transposition pattern, and can consequently be extended. Simpler transpositions often suffer from the property that keys very close to the correct key will reveal long sections of legible plaintext interspersed by gibberish. Consequently, such ciphers may be vulnerable to optimum seeking algorithms such as genetic algorithms and hill-climbing algorithms . There are several specific methods for attacking messages encoded using

3975-473: The position of units of plaintext but instead change the units themselves. Despite the difference between transposition and substitution operations, they are often combined, as in historical ciphers like the ADFGVX cipher or complex high-quality encryption methods like the modern Advanced Encryption Standard (AES). Plaintexts can be rearranged into a ciphertext using a key , scrambling the order of characters like

4050-448: The same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=K37&oldid=1107805567 " Category : Letter–number combination disambiguation pages Hidden categories: Short description

4125-448: The shuffled pieces of a jigsaw puzzle . The resulting message is hard to decipher without the key because there are many ways the characters can be arranged. For example, the plaintext "THIS IS WIKIPEDIA" could be encrypted to "TWDIP SIHII IKASE". To decipher the encrypted message without the key, an attacker could try to guess possible words and phrases like DIATHESIS, DISSIPATE, WIDTH, etc., but it would take them some time to reconstruct

4200-431: The spaces are left blank. Finally, the message is read off in columns, in the order specified by the keyword. For example, suppose we use the keyword ZEBRAS and the message WE ARE DISCOVERED. FLEE AT ONCE . In a regular columnar transposition, we write this into the grid as follows: providing five nulls ( QKJEU ), these letters can be randomly selected as they just fill out the incomplete columns and are not part of

4275-579: The spring 1943, Buggisch conducted general investigations into the small technique TECHNIK Hagelin machine. The Swedish firm, A.B. Cryptograph , Stockholm produced an early type of Hagelin machine known as TEKNIK. One example of the BC 38 device was received from the Wa Pruef 7/IV unit, together with the statement that Boris Hagelin was working in America. The BC38 was a Swedish Hagelin machine. An engineer called Voss, who

4350-505: The spring. Later, he conducted lectures on theory, specifically discussing depth problems, X and W methods. Towards the end of the year, in November 1943, Buggisch had a discussion with Korvettenkapitän Jaeckle. He has become acquainted with Jaeckle in 1943, when Jaeckle who was an ordinary Naval Signals Officer, had managed to get hold of a model of the M-209 cipher device and had worked out

4425-487: The theoretical foundations of an Allied ciphony apparatus from the captured Mustang a/c restored to working order by the German Aeronautical Research Institute by engineer Vegemund, who described its working to Buggisch. The investigations begun at Wa Pruef 7/IVe could not be carried very far owing to the general disorganization then beginning and the fall of Germany. Before the war, he taught at

4500-551: The war and revealed nothing to their German interrogators. Finally, in late 1943, early 1944 when the war had turned against Germany they had volunteered the information that the Enigma device had been broken by Polish cryptanalysts several years before the war, confirming German suspicions. During this period Buggisch was attached to the Communications Experimental Station, located in a cave in Staats . The station

4575-498: Was German knowledge, or supposed knowledge, that the Enigma cipher machine and therefore its own key processes, were not secure and had already been read by the Allies. The Fall Wicher was the knowledge that was received from two Polish officers being held in a concentration camp who had been captured in France in 1940. The two officers had been repeatedly interviewed in the intervening years of

SECTION 60

#1732905184146

4650-574: Was a German spy in Sweden, had informed Germany that the US was planning to adopt a Hagelin idea. Buggisch and his team had investigated the Hagelin machine for security weaknesses. Buggisch also conducted research into Enigma machine 39 during this period. He also started work on a future German Standard Cypher teleprinter standard. French C36 messages appeared in the 5-figure Charles de Gaulle code traffic again, with

4725-664: Was also machine ciphers, on Russian cypher teleprinters, i.e. the Russian Fish device, cribs and supposed results of the device from the Forschungsamt . He also worked on the Enigma specifically crib problems, Bigram systems. On the Converted 209, he worked on column separation (German: Spaltentren-nung ). He also conducted continued research on the C36 messages, looking at messages with complicated enciphering techniques, which were solved in

4800-454: Was attacked individually. A variant form of columnar transposition, proposed by Émile Victor Théodore Myszkowski in 1902, requires a keyword with recurrent letters. In usual practice, subsequent occurrences of a keyword letter are treated as if the next letter in alphabetical order, e.g., the keyword TOMATO yields a numeric keystring of "532164." In Myszkowski transposition, recurrent keyword letters are numbered identically, TOMATO yielding

4875-447: Was generally regarded as the most complicated cipher that an agent could operate reliably under difficult field conditions. The double transposition cipher can be treated as a single transposition with a key as long as the product of the lengths of the two keys. In late 2013, a double transposition challenge, regarded by its author as undecipherable, was solved by George Lasry using a divide-and-conquer approach where each transposition

4950-507: Was often obtained, so that the recipher could easily be stripped by well known methods. The K37 was the Russian Crystal cipher machine, that worked on the same principle as the B211 cipher, but a more primitive cipher. The K37 machine was different from the B211 in lacking the (German: Surchiffreur ) or German: Ueberschluesseler , a sort of Enigma wheel by which the path of the current

5025-517: Was part of the Army Ordnance Branch, department WA Pruef 7, Section IV, Referat A from June 1944. He worked on the mathematical treatment of ciphony systems. During this period Buggisch also worked almost exclusively on Russian X ciphony device. He also worked on the T52 teleprinter frequency Undulator device. Later work was the theoretical investigations into the construction of Tigerstedt keys, from

5100-561: Was posted and attached to an intercept station in Berlin at 29/30 Bendlerstrasse , where there were other specialist sections for interception of Russian and Balkan traffic. During this period, he undertook the completion of two works on the C-36 Cipher machine, while working with the team which included Erich Hüttenhain , the chief cryptanalyst of OKW/Chi and Fritz Menzer , the hand and machine cipher designer and inventor. Buggisch also studied

5175-405: Was studied in detail, using traffic collected from two years before. A theoretical solution to the B211 code was developed by the group and back traffic was actually solved. However, the method did not work in practice when B211 traffic was again encountered. Buggisch did not mention any other solutions. In August 1942, Inspectorate 7/VI were again under reorganization. Buggisch was transferred to

5250-453: Was subordinated to Hauptmann Walter Mettig, a signals officer, who became second-in-command of OKW/Chi . Together with his colleague, the mathematician, Wolfgang Franz , they initially worked on French Army cipher systems before and during the Battle of France . These were the F90, F110 ciphers, known by their German designations and were based on 4-figure codes. In one case the recipher consisted of

5325-563: Was the Chief Signals Officer and Chief of the Armed Forces Signal Communications Office. The Chi conference took place over a period of three months from November 1944 through January 1945. Gimmler had insisted on them, although the mathematician Erich Hüttenhain who also worked an OKW/Chi, was against them, and felt it was a waste of time to gather formally to hear reports. In spite of this, Hüttenhain held

5400-511: Was the first key recovery from a crib. Major Lechner was head of Section Inspectorate 7/VI. During this period Buggisch conducted conferences with OKW/Chi regarding security studies on the BC38 device, which was the Swedish Hagelin cipher machine, on the Enigma cipher machine and on the cypher teleprinter with Karl Stein and with Gisbert Hasenjaeger . During the summer Buggisch worked on and broke

5475-471: Was the official Russian designation for the Soviet (Russian) 5/F or 5-figure operational code. It contained 25,000 groups namely all the five-figure numbers and only these, in which the first three figures were all simultaneously odd or simultaneously even. For recyphering the add [subtractor] or 300 5/F groups were in general use by the Soviets. The code was used from about the end of June 1941 to September 1941, by

5550-631: Was transferred to the Balkans specialist section that was directed by Rudolf Bailovic . Buggisch worked on the Greek 5-figure transposition cipher. Two memoranda were issued concerning the JUGO – SLAV code. Around 1 February 1941, all cryptanlysts including Buggisch were transferred from the Intercept station to the Inspectorate 7 unit, later called the General der Nachrichtenaufklärung . In June 1941, Buggisch moved to

5625-408: Was turned to another channel at one point, crossing over and exchanging positions with another path instead of continuing parallel. Buggisch called this the X effect, and stated it greatly complicated cryptanalysis , as it was hard to tell when it was being employed in place of the parallels. A model was captured in 1941. Analysis by Buggisch and Herbert von Denffer found that it could be solved on

#145854