66:
1583:
420:
128:
485:
394:
473:
461:
501:
25:
197:
1602:
model had been modified with the old reflector replaced by a thin rotor and a new thin reflector. Breaking Shark on 3-rotor bombes would have taken 50 to 100 times as long as an average Air Force or Army message. It seemed, therefore, that effective, fast, 4-rotor bombes were the only way forward.
706:
This table shows how the internal wiring connects the right side of the rotor (with the spring-loaded contacts) to the left side. Each rotor is a simple substitution cipher. The letters are listed as connected to alphabet order. If the first letter of a rotor is
634:, are used to change the position of the alphabet ring relative to the internal wiring. Notch and alphabet ring are fixed together. Changing the ring setting will therefore change the positions of the wiring, relative to the turnover-point and start position.
1594:
The introduction of the fourth rotor was anticipated because captured material dated
January 1941 had made reference to the development of a fourth rotor wheel; indeed, the wiring of the new fourth rotor had already been worked out.
484:
1378:
Swiss Army Enigma machines were the only machines modified. The surviving Swiss Air Force machines do not show any signs of modification. Machines used by the diplomatic service apparently were not altered either.
472:
1367:
One of the modifications consisted in modifying the wheel stepping on the Swiss Army machine. The slow, left-hand wheel was made stationary during operation while the second wheel stepped with every key
504:
The scrambling action of the Enigma rotors shown for two consecutive letters — current is passed through the rotors, around the reflector, and back out through the rotors again.
1480:
In the following examples you can observe a normal step sequence and a double step sequence. The used rotors are (from left to right) I, II, III, with turnovers on
385:. Understanding the way the machine encrypts requires taking into account the current position of each rotor, the ring setting and its internal wiring.
1363:
In 1941 it became known to the Swiss that some of their Enigma traffic was being read by the French. It was decided to make some design modifications.
490:
The left side of an Enigma rotor, showing the flat (plate) electrical contacts. A single turnover notch is visible on the left edge of the rotor.
1704:
1387:
The single turnover notch positioned on the left side (plate connector side) of the rotor triggers the stepping motion by engaging the
1598:
On 1 February 1942, the Enigma messages began to be encoded using a new Enigma version that had been brought into use. The previous
659:
As mentioned before these encodings only happen after the key is pressed and the rotor has turned. Tracing the signal on the rotors
368:
1374:
The stationary but rotatable left-hand wheel was meant to make up for the missing stecker connections on the commercial machine.
572:
When a rotor has stepped, the offset must be taken into account to know what the output is, and where it enters the next rotor.
1391:
of the wheel to the left. Later rotors had two turnover notches. The table below lists the turnover notch point of each rotor.
506:
Note: The grayed-out lines represent other possible circuits within each rotor, which are hard-wired to contacts on each rotor.
522:
As an example, let us take rotor type I of Enigma I (see table below) without any ring setting offset. It can be seen that an
38:
511:
No letter can map to itself, a cryptographic weakness caused by the same wires being used for forwards and backwards legs.
478:
The right side of a rotor, showing the pin electrical contacts. The Roman numeral V identifies the wiring of the rotor.
174:
109:
87:
52:
80:
1603:
Encoding mistakes by cipher clerks allowed the
British to determine the wiring of the new reflector and its rotor.
1555:— right rotor steps, takes middle rotor (II) one step further, which is now in its own E—notch position
1577:
1675:
398:
361:
224:
1371:
The third wheel and the UKW would step in the normal fashion with Enigma stepping for the third wheel.
149:
140:
44:
74:
1719:
780:
354:
286:
234:
91:
737:
The reflector is also known as the reversing drum or, from the German, the
Umkehrwalze or UKW.
145:
341:
259:
249:
239:
1561:— normal step of right rotor, double step of middle rotor, normal step of left rotor
8:
1620:
1582:
244:
1689:
1669:
663:
is therefore only possible if a key is pressed while the rotors were in the position
1699:
264:
1599:
1587:
382:
271:
204:
1713:
1388:
519:
The effect of rotation on the rotors can be demonstrated with some examples.
419:
1659:
281:
1694:
127:
276:
569:. Notice that the wirings are connected as a loop between two letters.
254:
1664:, Kew, Richmond, Surrey, TW9 4DU: National Archives, Reference HW 25/2
1469:
If rotor steps from Z to A, or from M to N the next rotor is advanced
393:
1088:
460:
318:
1590:(M4) which was introduced for U-boat traffic on 1 February 1942.
500:
397:
Detail of rotor internal structure and wiring on display at the
381:
This article contains technical details about the rotors of the
1355:
Technical comments related to Enigma modifications 1939-1945.
637:
The ring setting will rotate the wiring. Where rotor I in the
196:
1492:. It is the right rotor's behavior we observe here (turnover
323:
311:
306:
301:
296:
291:
727:; such looped wiring is only the case with the reflectors.
602:
With the rotors I, II and III (from left to right), wide
1549:— right rotor (III) goes in V—notch position
1516:— right rotor (III) goes in V—notch position
1522:— right rotor takes middle rotor one step further
1458:
If rotor steps from Z to A, the next rotor is advanced
1447:
If rotor steps from J to K, the next rotor is advanced
1436:
If rotor steps from V to W, the next rotor is advanced
1425:
If rotor steps from E to F, the next rotor is advanced
1414:
If rotor steps from Q to R, the next rotor is advanced
678:
With the rotors I, II, III (from left to right), wide
549:
In the case of the reflectors, in this example Wide
546:. Notice that every letter is encoded into another.
553:is taken (Reflector B in the table below) where an
1711:
1475:
362:
388:
1382:
53:Learn how and when to remove these messages
369:
355:
16:Technical details about the Enigma machine
1642:
1640:
175:Learn how and when to remove this message
110:Learn how and when to remove this message
1581:
499:
495:
392:
73:This article includes a list of general
1712:
1637:
701:
1657:
1646:
1661:The History of Hut 8 1939–1945
121:
59:
18:
13:
1567:— normal step of right rotor
1543:— normal step of right rotor
1528:— normal step of right rotor
1510:— normal step of right rotor
694:will produce the encoded sequence
618:will produce the encoded sequence
445:spring-loaded ring adjusting lever
79:it lacks sufficient corresponding
14:
1731:
1683:
667:and the ring settings are all on
575:If for example rotor I is in the
407:Exploded view of an Enigma rotor
34:This article has multiple issues.
483:
471:
459:
418:
195:
126:
64:
23:
1578:M4 (German Navy 4-rotor Enigma)
1571:
625:
514:
42:or discuss these issues on the
1613:
641:-position normally encodes an
399:US National Cryptologic Museum
1:
1606:
1202:M3 & M4 Naval (FEB 1942)
1186:M3 & M4 Naval (FEB 1942)
1170:M3 & M4 Naval (FEB 1942)
649:, with a ring setting offset
595:enters the next rotor in the
591:. Because of the offset this
653:-02 it will be encoded into
7:
1476:Normalized Enigma sequences
430:marking dot for "A" contact
139:to comply with Knowledge's
10:
1736:
1575:
1358:
1343:ABCDEFGHIJKLMNOPQRSTUVWXYZ
1327:RDOBJNTKVEHMLFCWZAXGYIPSUQ
1311:ENKQAUYWJICOPBLMDXZVFTHRGS
1297:FVPJIAOYEDRZXWGCTKUQSBNMHL
1283:YRUHQSLDPXNGOKMIEBFZCWVJAT
1269:EJMZALYXVBWFCRQUONTSPIKHGD
1253:FSOKANUERHMBTIYCWLQPZXVGJD
1237:LEYJVCNIXWPBQMDRTAKZGFUHOS
1221:ABCDEFGHIJKLMNOPQRSTUVWXYZ
1195:FKQHTLXOCBJSPDZRAMEWNIUYGV
1179:NZJHGRCXMYSWBOUFAIVLPEKQDT
1163:JPGVOUMFYQBENHZRDKASXLICTW
1147:VZBRGITYUPSDNHLXAWMJQOFECK
1131:ESOVPZJAYQUIRHXLNFTGKDCMWB
1115:BDFHJLCPRTXVZNYEIWGAKMUSQO
1099:AJDKSIRUXBLHWTMCQGZNPYFVOE
1081:EKMFLGDQVZNTOWYHXUSPAIBRCJ
1065:ABCDEFGHIJKLMNOPQRSTUVWXYZ
1039:QWERTZUIOASDFGHJKPYXCVBNML
1020:IMETCGFRAYSQBZXWLHKDVUPOJN
1001:EHRVXGAOBQUSIMZFLYNWKTPDJC
982:ZOUESYDKFWPCIQXHMVBLGNJRAT
963:PEZUOHXSCVFMTBGLRINQJWAYDK
944:ABCDEFGHIJKLMNOPQRSTUVWXYZ
918:QWERTZUIOASDFGHJKPYXCVBNML
902:QYHOGNECVPUZTFDJAXWMKISRBL
886:JVIUBHTCDYAKEQZPOSGXNRMWFL
870:NTZPSFBOKMWRCJDIVLAEYUXHGQ
854:JGDQOXUSCAMIFRVTPNEWKBLZYH
838:ABCDEFGHIJKLMNOPQRSTUVWXYZ
814:UQNTLSZFMREHDPXKIBVYGJCWOA
795:HQZGPJTMOBLNCIFDYAWVEUSRKX
773:DMTWSILRUYQNKFEJCAZBPGXOHV
754:ABCDEFGHIJKLMNOPQRSTUVWXYZ
719:. This does not mean that
413:Three rotors in sequence
409:
406:
389:Physical design of rotors
190:The Enigma cipher machine
1674:: CS1 maint: location (
1586:The German Navy 4-rotor
1383:Turnover notch positions
1228:Model Name & Number
1072:Model Name & Number
951:Model Name & Number
925:German Railway (Rocket)
909:German Railway (Rocket)
893:German Railway (Rocket)
877:German Railway (Rocket)
861:German Railway (Rocket)
845:Model Name & Number
761:Model Name & Number
152:may contain suggestions.
137:may need to be rewritten
821:Commercial Enigma A, B
802:Commercial Enigma A, B
682:, all ring settings in
606:, all ring settings in
94:more precise citations.
1700:ultraenigmawirings.htm
1591:
711:, this means that the
630:The ring settings, or
587:which is wired to the
508:
401:
1658:Mahon, A. P. (1945),
1585:
1534:Double step sequence:
686:, and start position
610:, and start position
583:enters at the letter
503:
496:Rotor electrical view
396:
1625:www.cryptomuseum.com
235:Polish Cipher Bureau
746:
702:Rotor wiring tables
1592:
1334:M4 R1 (M3 + Thin)
1318:M4 R1 (M3 + Thin)
742:
565:is returned as an
509:
402:
1473:
1472:
1353:
1352:
1323:Reflector C Thin
1307:Reflector B Thin
781:Commercial Enigma
557:is returned as a
542:is encoded as an
526:is encoded as an
467:
466:
379:
378:
185:
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167:
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141:quality standards
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1501:Normal sequence:
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1225:Date Introduced
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1069:Date Introduced
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948:Date Introduced
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922:7 February 1941
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906:7 February 1941
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890:7 February 1941
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874:7 February 1941
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858:7 February 1941
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842:Date Introduced
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758:Date Introduced
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715:is wired to the
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439:wire connections
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90:this article by
81:inline citations
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1695:enigmabombe.htm
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1621:"Enigma wiring"
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225:Breaking Enigma
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86:Please help to
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1684:External links
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1600:3-rotor Enigma
1588:Enigma machine
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579:-position, an
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100:December 2014
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1690:enigvar2.pdf
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1649:, p. 62
1628:. Retrieved
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1572:Fourth rotor
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1479:
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1293:Reflector C
1279:Reflector B
1265:Reflector A
1257:Spring 1942
1241:Spring 1941
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744:Rotor Wiring
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723:is wired to
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632:Ringstellung
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626:Ring setting
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451:finger wheel
442:pin contacts
427:notched ring
380:
214:
171:
158:January 2022
155:
146:You can help
136:
106:
97:
78:
50:
43:
37:
36:Please help
33:
731:Terminology
680:B-reflector
604:B-reflector
282:Herivel tip
277:Banburismus
92:introducing
1647:Mahon 1945
1630:2022-06-09
1607:References
1576:See also:
684:B-position
608:A-position
599:position.
255:Cyclometer
75:references
39:improve it
1705:g-312.zip
1349:Enigma I
1122:Enigma I
1106:Enigma I
690:, typing
614:, typing
150:talk page
45:talk page
1714:Category
1670:citation
1217:Rotor #
1154:M3 Army
1138:M3 Army
1089:Enigma I
1061:Rotor #
1046:Swiss K
1027:Swiss K
1008:Swiss K
989:Swiss K
970:Swiss K
940:Rotor #
834:Rotor #
750:Rotor #
645:into an
561:and the
538:, and a
319:PC Bruno
1403:Effect
1368:stroke.
1359:Swiss K
410:
333:Related
240:Doubles
88:improve
1400:Notch
1397:Rotor
1260:M4 R2
1249:Gamma
1244:M4 R2
148:. The
77:, but
1331:1940
1315:1940
1233:Beta
1199:1939
1191:VIII
1183:1939
1167:1939
1119:1930
1103:1930
1085:1930
818:1924
799:1924
783:A, B
777:1924
696:EWTYX
692:AAAAA
620:BDZGO
616:AAAAA
342:Ultra
324:Cadix
312:Hut 8
307:Hut 6
302:Hut 4
297:Hut 3
292:Bombe
260:Bomba
250:Clock
245:Grill
1676:link
1488:and
1466:Z+M
1430:III
1339:ETW
1175:VII
1111:III
1032:ETW-
1013:UKW-
994:III-
914:ETW
898:UKW
882:III
530:, a
287:Crib
1565:BFY
1559:BFX
1553:AEW
1547:ADV
1541:ADU
1526:ABX
1520:ABW
1514:AAV
1508:AAU
1496:).
1441:IV
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1159:VI
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975:II-
866:II
807:III
688:AAA
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448:hub
1716::
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1668:{{
1639:^
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655:K
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639:A
597:J
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577:B
567:A
563:Y
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370:e
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