Talk:Enigma machine

From Wikipedia, the free encyclopedia

Featured article star Enigma machine is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Wikipedia community. If you can update or improve it, please do.
Main Page trophy Enigma machine appeared on Wikipedia's Main Page as Today's featured article on October 13, 2004.
WikiProject on Cryptography This article is part of WikiProject Cryptography, an attempt to build a comprehensive and detailed guide to cryptography in the Wikipedia. If you would like to participate, you can choose to edit the article attached to this page, or visit the project page, where you can join the project and see a list of open tasks.
WikiReader Cryptography It is intended that this article be included in WikiReader Cryptography, a WikiReader on the topic of cryptography. Help and comments for improving this article would be especially welcome. A tool for coordinating the editing and review of these articles is the daily article box.
WikiProject Spoken Wikipedia There is a request, submitted by (unknown), for an audio version of this article to be created.

See WikiProject Spoken Wikipedia for further information.

The rationale behind the request is: "Previously requested".

See also: Category:Spoken Wikipedia requests and Wikipedia:Spoken articles.
This article has been selected for Version 0.5 and the next release version of Wikipedia. This Engtech article has been rated FA-Class on the assessment scale.


Portal:Germany
 Germany Portal
This article is within the scope of WikiProject Germany, an attempt to build a comprehensive and detailed guide to articles related to Germany on Wikipedia. If you would like to participate, please join the project.
Featured article FA This article has been rated as FA-Class on the Project's quality scale.
(If you rated the article please give a short summary at comments to explain the ratings and/or to identify the strengths and weaknesses.)
Germany To-do:

To-do list for Enigma machine:

 edit - history - watch - refresh
  • Overview the various indicator procedures (now covered: pre WW2 procedure and WW2 wehrmacht/luftwaffe) Any other know procedure welcome
  • Expand subsections on Enigma components in "Description" section
  • Add inline references

Contents

[edit] Enigma Rotor Details

Please see the enigma rotor details page discussion.

[edit] PBS doc and three letter message setting. clarity?

I seem to remember from the PBS documentary on the subject that the three letter rotor setting was sent only in the army and airforce versions of the code, but in the naval enigma, the three letter setting was not sent, but was determined by codebooks, and that made it more difficult to break, needing the capture of codebooks to do it. Does someone else remember the same? --AN


AN:
Indeed the Navy Engima was harder to break from the beginning and throughout. It encrypted the intial settings in a way that the Army, Air Force, Abwehr, and SD Enigma operating procedures did not. And, indeed, captured material from U-boats, weather trawlers, and the small vessel Krebs in the Loftein Islands helped considerably with the Navy Engima.
As well, the operator selected three letter start position setting (sent twice in succession) was not used in the Navy. Even the Army abandoned it relatively early on. My memory is that the Poles had to cope with that, among other things, before it became obvious they'd have to throw in the towel.
Yep, the Navy procedure was different from quite early on. The doubled three-letter indicator procedure was abandoned by the Army and Air Force nets in May 1940 (except for a Norwegian key, apparently). The Poles had already handled an earlier change of indicator procedure before the war; more precisely, instead of using a "ground setting" to encrypt the indicator twice, they chose their own initial setting, and sent it along with the message in the clear. This stymied the Polish techniques (the "characteristic" method) for only a month or two, and they quickly responded with the Bomba and the Zygalski sheets. What really stopped them (while they were in Poland) was the introduction of two new wheels and the increasing of the number of plugboard connections; or maybe it was that they got invaded ;-) Anyway, once the British had punched them a larger collection of perforated sheets they could carry on in France. — Matt 12:58, 13 Aug 2004 (UTC)
So the PBS documentary is correct, but if it implied that the Army, Air Force, or Navy Enigma procedures remained the same for very long it is essentially wrong.
Hope this helps.
ww

[edit] Enigma and disambiguation

We need to make Enigma a disambiguation page.

Recommend moving to Enigma machine

(related comments squeezed together by Mulad, May 29, 2003)

This has been done. — Matt 05:48, 29 Jul 2004 (UTC)
The "band" is now Enigma (musical project), but i'm not quite prepared to confusing things by fixing your now double-redirected link to it, OK? --Jerzy(t) 00:10, 2004 Nov 16 (UTC)

[edit] German name

I've just noticed that this article doesn't mention *anywhere* that Enigma isn't the real name of the machine, it was a name given to it by one of the groups that tried to crack it. I'll try and track down the real German name, but I'm posting this in case anyone happens to know it without needing to look it up. --AW

Poking around the web, I've found references that indicate the German name for the Enigma machine was "Schlüssel M". This may be specific to the naval version of the machine; it's not clear to me if other versions had a different name.
See, e.g.:
[1]
[2]
Ortonmc 20:29, 8 Sep 2003 (UTC)
Adam:
I've just noticed your comment about the name Enigma. Sorry it took me so long. It's my understanding that the name actually was chosen by Scherbius (or someone at the firm) and the product was offered commecially under Enigma (or some German name meaning Enigma). After Scherbius's death, the firm essentially went broke and was reorganized under the name (spelling is shakey, this is from memory) Heimsoth and Reinke. This version of the company continued in operation till the end of the War. Enigma machines (there were many variations) were eventually made by several firms, including the Olympia typewriter company (!) as production demands increased beyond what H&R could manage.
On the cryptanalysis side, the British Post Office (the Bell System of Britain) (in particular the Dollis Hill Works) made various bombes (akin to the Polish designs of the '30s) and assorted other code breaking machinery (eg, the Heath Robinsons and the Collossi) for the people at Bletchley Park, while in the US, NCR (and some others) made several bombe variants for Army and Navy (in quantities that astonished the British), and late in the war made quite a few special purpose machines (generically called RAM -- but not meaning random access memory, that came later) for both Army and Navy and (shortly after the War) for the ASA which resulted from the merger of the Army and Navy former girls' schools. The individual names for these things are quite varied, and I haven't yet come across an account of which one was what and built when.
Hope this helps. See Bamford's Puzzle Palace and Body of Secrets, and Budiansky's Battle of Wits for additional info and pointers into the literature.
ww

[edit] Algebraic representation of Enigma action

I'm trying to figure out how to express the action of the Enigma machine algrebraically. As far as I can determine, the situation is as follows:

The wiring of each rotor is a fixed permutation pi, chosen from a set of 5 permutations labelled I, II, ..., IV. The rotational position of the rotor i is represented as a power ki of a cyclic permutation c of order 26 ("A"c = "B", "B"c = "C", ..., "Z"c = "A"). The action of a single rotor on a letter x is by the permutation x.(c-ki pi cki).

The three rotors in sequence form the composition p

p = (c^{-k_1} p_1 c^{k_1})(c^{-k_2} p_2 c^{k_2})(c^{-k_3} p_3 c^{k_3})

The reflector r is a permutation which is a derangement of order 2 (i.e., x.r ≠ x, and r2 = 1). The plug-board is another permutation b, also of order 2. To encode a letter x, we then apply the permutation

x.(bprp − 1b − 1) = x.(bp)r(bp) − 1

Note that we have that (b p)r(b p) -1 is also always a derangement of order 2, since it is conjugate to r.

An additional possible complication, not present in the military Enigma, is that the keys/bulbs might be initially wired to the procession of rotors in a number of ways, for example through a permutation g. This would result in a permutation (b g p)r(b g p) -1; but in the miltary Enigma, g is the identity.

The values of ki alter after each digit is encoded; this appears to be controlled by two initial settings: for each rotor, there is an offset ti between the letters written on the outer ring and the actual encoding ring; and there is the initial rotor position or message key given as a letter ai. If we comine these two values, zi = (ti - ai) mod 26, we obtain as base value z = z1 + z2*26 + z3*262. Then we can calculate ki above for the encoding pattern of the nth digit of the message, with each ki being a digit of the number (z+n) base 26.

Is this correct? Chas zzz brown 03:04 Mar 23, 2003 (UTC)

Almost correct (for a 3-rotor WWII German military machine, etc); the only problem is that the sequence of the ki is slighly different to how you describe it. The Enigma rotors do not step quite like an automobile odometer; sometimes the second rotor steps twice consecutively. — Matt 21:19, 7 Sep 2004 (UTC)
Chas:
Have also just noticed your request for comment. You are attempting an interesting problem, but an indeterminate one. The German government (Army, Gestapo, Abwehr, SD, Navy, ...) Enigmas were not one machine; the commercial one may have been. For instance, at least one Abwehr Enigma used 4 rotors -- but had no plugboard. The first Navy Enigmas had no plugboard but used 3 out of 5 rotors. The first Army Enigmas distributed only three rotors initially; moving to match the Navy's use of 3 out of 5 only later. The Army Enigmas either started out with plugboards or added them very early, I can't remember which. The Navy's 4th rotor wasn't actually a full rotor but a simplified half rotor (which may or may not have been the same as the Abwehr's 4th rotor, I have no info) and didn't appear until well into the War. And there were at least two 'sizes' of plugboards.
So you see that there can be no one algebraic discription of 'the' Enigma as there were several Enigmas. Perhaps the most interesting project would be a description of the early Army Enigma that Rejewski broke; it certainly has pride of place cryptanalytically.
ww

[edit] Rejewski and Enigma manuals

According to Simon Singh in the codebook the term enigma actually appeared in the title of both the manuals in agent asch's posession that the spy codenamed 'rex' photographed.

I am not sure that rejewski never found out about the manuals as the article currently states. it was my understanding from reading the codebook that the manuals asch had access to were instrumental to rejewski constructing his bombes. i cant find my copy of the book but could someone check this fact?

User:jy 21:18, 22 Dec 2003 (UTC)

jy,
My memory of the sequence is that Rejewski was not even told of the material the French had gotten from Asch and passed to the Poles until he had made the fundamental conceptual breakthrough in 32/33. Thereafter, I suspect that they were given whatever material was available to increase the efficiency of their efforts. But I can't recall reading that exactly.
Hope that helps.
ww
ok ive just flicked through the code book again. singh gives the impression that rejewski began the work without the manuals of Schmidt (Asch). He made substantial efforts toward cracking the cipher but he required the manuals in order to 'access replica enigma machines'. singh essentially says no messages were decoded until after the french handed over the manuals and these were instrumental to rejewski's progression
Jy

[edit] General thoughts

At Ww's suggestion, I (someone unfamiliar with cryptography, except for Singh's excllent book) gave this a look to see how it looks to us amateurs. :-) Looks good, actually. Early on in Operations, though, several references are made to a picture that doesn't seem to be there. If the picture referenced is the one at the top of the article, it should be moved.....but actually, it's hard to see the details in that picture that are being referred to in the Operations Section. Is a large pic available?

In the "Basic Cryptanalysis" section, I think you take too much time trying to cover cryptanalysis in the abstract....I start to wonder what all this has to do with Enigma. I'd cut a lot of it, and focus on the cryptanalysis done on Enigma (I think it's right to note a couple of principles that people should consider when reading, but really if you think they'll need to know about cryptanalysis, I'd just drop a link to that article).

The description of Enigma's method of encoding is hard to follow....though I think it's well written. But it's such a complex scheme that I had trouble following it (and I've read Singh's book at least twice). I think a diagram would be useful -- I would encourage one of you crypto fanatics to do it in a drawing program somehow. Singh has great diagrams, as I recall, which are of course copyright, but I think if we could build something like that for illustrative purposes here, it would be great -- certainly it helped me understand his book.

Also, in a couple of places the text feels like it's been edited over a few too many times. For example, you make casual reference to "Ultra" before explaining what Ultra was, probably because that paragraph has been cut and added to many many times. I'd suggest someone go through very carefully and make sure that codenames and cryptographical terms are explained at their first mention, and that the style is generally fluid. I think the article generally reads well, though -- not a big deal.

Finally, in the middle I start to swim in the expanse of text. I think a few more carefully placed headers would help me see the structure of the article more clearly, and move through it more efficiently as a reader. I hope no one thinks my ideas are a criticism of some excellent work here -- this is a great article! But I'm trying to help out with a little peer review. If you need me to explain any of this, feel free to drop me a note, or leave a response here. Keep up the great work! Jwrosenzweig 20:39, 15 Apr 2004 (UTC)

[edit] Requested article: Bombe (Wikispam)

Hi, I'd love to read an article about the bombe used to break the Enigma, and not having the prerequisite knowledge have offered an exciting ψ5 bounty for the author in the hope that I can entice someone else to do the work for me... — Matt 17:58, 16 Apr 2004 (UTC)

Matt, Just the thought of w 5 has me antsy. I'll add it to my list of pending work. Actually, you're right about interesting. The Poles (mostly Rejewski, Zygalski, and Różycki as I follow it) first developed something called a cyclometer, and only then the bomba proper. But they never had the resources (these things were being built by a little machine shop operation partially owned by one of the BS folks (Antoni Palluth?); and some of their personnel were captured by the Germans who seem to have failed to use their renowned methods on them, else they would have learned Enigma had been broken), and BP had larger and faster bombes built. Note name change! When the need for speed increased still more, the Brits were up against resource limits and so after much political wrnagling back and forth, the USA and USN both designed and had built much larger bombes (probably shortened in the inimitible American fashion in at least some instances to bombs) by, among others, the National Cash Register Corp in Dayton. They flew, though with persistent mechanical troubles (brushes fail to work properly at surface speeds in excess of some -- apparently troublesome) limit. It was the threat of these machines that seems to have settled the political wrangling twixt BP (and their masters in SIS/UK) and the assorted (also wrangling amonst themselves) American crypto outfits.
What I'm just drooling to know though, is whether bomba were actually named from a sort of ice cream dish in Poland? Or (say it ain't so!!) just the noise them made (a sort of ticking apparently) while they ran. Never have heard a credible answer to that one.
ww 19:21, 18 Apr 2004 (UTC)

[edit] Comments

Common name: the name used in the under the cover instruction refers to the machine as a "lamp box" which makes sense because of the function of the lights when the keys are held down. The instuctions refer to the long-term maintenance of the machine, the electrical contacts tend to oxidize with no use and using the machine, sometimes forcefully depressing the keys abrades the contacts to keep the machine functioning. The German and its English translated instruction are easily obtained from my files or from the Web. Do not disregard the oval Enigma logo, that was the company's.

--enm 14 May 2004, 11:00 PDT

P.S. http://frode.home.cern.ch/frode/crypto/simula/index.html has the product logo which shows its name (Enigma). 14 May 2004, 11:30 PDT

[edit] General thoughts

Generally a very nice page, well written, but it speaks more about cracking Engima than the machine itself. The naval historian Norman Polmar and others have written a few other interesting things.

The shear numbers are worth knowing. Something between 100,000 to 200,000 Engimas were manufactured (and variants were used until 1990).

Budiansky is good for the numbers of Turing Bombes and Colossi: about 300 and 1-2 dozen, and some visible (in the USA) and rebuilds of each at Bletchley Park, UK.

Polmar in his Spy Book, encyclopedia also noted that the US Army apparently purchased an Enigma for about $250 about 1928 or 1929 and decided against using them. If this is true, numerous questions arise like what the final disposition of this machine was? Did Herbert Yardley ever encounter this machine? And more.

The plugboard, the Steckerboard, was thought by the German Army to add an additional level of security (it didn't), so it was added and that won the contract and begat the mass manufacturing.

I just noticed this comment, sorry. I seem to remember that the stecker was between keys and rotor, but there is no essential difference if it was between rotors and lamps.
Actually, the plugboard did add some security, as it effectively (in modern crypto terms) increased the key length. It increased an attacker's difficulty in determining the correspondence between keys and the first rotor and as a practical matter this was significant. This made a simple approach infeasible and was one of the reasons Dilly Knox (later of BP) was able to break commercial Enigma (presumably model D) but not the German Army version. He was not using Rejewski's inspired mathematical approach, nor his felicitous guess that the Germans would be (rather dimly/dumbly) methodical in assigning keys to intial rotor positions. ww 14:39, 21 Jun 2004 (UTC)

The design of the machine made certain that a letter did not map to itself. This was one of the design flaws which enabled Rajewski to get a toe hold at reducing the combinatorics.


--enm 14 May 2004, 11:12 PDT

[edit] Triton

I have some doubts about "a U boat mistakenly transmitted a messsage using Triton before it was due to be implemented. Realising the error, they re-transmitted the same message using pre-Triton 3 rotor Enigma". The Triton system let the fourth rotor be operated in a fixed position so that it could communicate with three rotor Enigmas, notably those which continued to be used by the weather service. Did the submarine really use a different machine or did it just lock out the fourth rotor? Jamesday 02:00, 21 Jun 2004 (UTC)

My memory of this is that the new 4 (or 3.5 if you want to be picky) rotor machines were distributed as possible (ie, when a U-boat or other candidate got back in) and the conversion was to have happened on the morning of such and such a day. Someone on one of the boats had the new machine, but mistakenly used it in 4 rotor mode prior to the effective date and then repeated encryption of the same plaintext in the works_like_the_3_rotor machine compatibilty mode after they realized what they'd done. This was a large crib for BP. Hope this helps. ww 14:29, 21 Jun 2004 (UTC)

[edit] JN-25 Fabrications

Hi All:

I'm not really a Wiki contributor, but I have writings online and Wiki folk have ported some of them to the Wiki. I have a crypto document and parts of it ended up in Wiki, courtesy of Matt. I was checking them over and got to prowling around for more crypto data for the next revision of my document.

I notice on the Enigma page comments that some stories about British penetrations of Japanese codes were fabrications. This rang a bell. In an early release of my own document, I had commented that there were conspiracy theories that the British had cracked JN-25, knew the Japanese were about to attack Pearl Harbor, and withheld the information to bring the US into the war.

This sounded preposterous on the face of it and I pretty much said so, but then I got a really flaming message from a Britisher over it, who vectored me to a page (I think it was the Bletchley Park website) that said the British *had* cracked JN-25. No details. It had the sound of something Tony Sale might say -- I respect Sale's knowledge and find him a good source of information, but he's got a bad case of "flag fever".

"OK, now I'm confused." What, I ask myself, did the British really know about Pearl Harbor? Now the Wiki article on the Enigma suggests that stories about British penetration of Japanese codes were to an extent a fabrication. That would simplify life for me (and give me a bit of satisfaction relative to my Yankophobic friend from the UK).

Any details or references on this matter? Comments would be appreciated.

Greg Goebel

Greg, JN-25 was introduced near the end of the 30s. It was a superencyphered code, originally a one book code, using Latin letters (and, I therefore presume, Romaji), and served as the highest level JIN command and control channel. There had been some success in breaking pre-Pearl Harbor JIN codes/cyphers by the Americans and I suppose others (as for instance in association with the Panay incident in which intercepted/decrypted traffic made clear the attack (by JIN Naval aviators) was not, as publicly claimed, a mistake), but there was little Fleet level traffic since most Japanese military activity was on land, and in any case, in China. If you have courier or mail or blinker light communications, you don't need radio, much less encrypted radio. Some progress was made against pre 12.41 versions of JN-25 (some sources claim that as much as 10% of message traffic in mid 41), but lacking sufficient depth, progress was slow. In 40(?) sometime, there was an agreement amongst the Dutch, British, and US to cooperate on Japanese communication cryptanalysis. No credible source of which I'm aware (specifically not including Stinnett in Day of Deceit (2000) -- his grasp of cryptanalytic reality at the time is distinctly limited (see Talk:Attack on Pearl Harbor for some comments)) claims more progress than that against any JN-25 version before 7.12.41. In any case, there was issued a new version of JN-25 on 1.12.41 and everyone was forced back to the start line. With more traffic available starting on the 7th (JIN operations now encompassed major areas away from the home islands -- SE Asia, the Philippines, etc -- and radio was required) the combination of USN Stations Hypo (Hawaii see Joseph Rochefort), Cast (Philippines), and OP-20-G (Washington), together with Hong Kong, Singapore (probably with some support from Bletchley Park), and Batavia made progress against the new version of JN-25. By spring of 42 it was clear some major new JIN operation was in the works, and by late May (just in time!) enough had been figured out about it (mostly from decrypted JN-25 traffic) that setting up the ambush at Midway became possible.
See Battle of Wits by Budiansky (US author), Station X and the Emperor's Codes(?) by Smith (?) (UK author), and Combined Fleet Decoded by Prados (US author) for mostly sensible more complete, and reflecting relatively recently available, information. Note that Prados' account, though valuable, is somewhat scattered amongst a larger story. A perusal of Harry Hinsley's books also will turn up (if memory serves) some commentary on British crypto operations against the Japanese. Henry Clausen's book about his investigation near the end of the War is also relevant in that he talked to just about everyone, carried an astonishing authorization brief from Stimson, and reports no evidence of anyone reading anything other than diplomatic codes/cyphers. However, note that there are two structural problems (at least) with any argument that JN-25 was not readable prior to 7.12.41. First, information release (some material is still classified in the UK or US, though that has been easing in the last decade or so) making older references less than complete (and, sometimes innocently, misleading, eg some of the claims in Farago's work) and, second, it's not possible to prove a negative proposition. Believers can still claim that the information (ie, that JN-25 was fully read prior to 7.12.41) is still classified and that the lack of evidence means nothing.
There have been various claims made about the state of US/UK/Dutch information prior to 7.12.41 (from various sources). The claims began as early as 8.12.41 (in a recorded comment made by a Congressman, Guy Gillette), and at least initially were politically motivated. Later on was added to the politics in some cases, a little understanding that some Japanese codes or cyphers had been broken, but not much understanding of the context.
In particular, it is sometimes said that Purple decryptions foretold Pearl Harbor -- not so, as the Japanese Foreign Office was out of the militaristic loop in control of Japan in part because they were thought to be insufficiently hard nosed. And that JN-25 (or other systems) had been broken -- by the British, or Dutch, or someone. The most credible of these is probably Rusbridger's book, but his source (ie, R Nave's diaries of the time) doesn't support his claims, so its credibility is rather strained as a result. Stinnett claims that JN-25 (which he calls 5-num) was broken by OP-20-G in part because they had produced a manual for its cryptanalysis. This lacks credibility since much depth is required for such a cryptanalysis, the method to be used could be understood prior to being able to apply it, and not very much traffic was available prior to the end of 41 to apply such a method. And there are assorted claims that US crypto (or signals traffic analysis) had the attack force located and tracked across the Pacific after it left the Kuriles (eg, Toland in Infamy). Some of Toland's informants went public and disputed his account of their experience (eg, Ogg who was Seaman Z, if my memory of the pseudonyms is correct) and the two strains of they knew in Washington from the Dutch seem to have little behind them, as nearly as I can make out. Nonetheless, there have been History Channel documentaries citing such 'evidence' of foreknowledge. They get seen by far larger numbers than read any of the more plausible accounts, which helps keep the foreknowledge conspiracy pot a-boilin'.
I trust this helps some. If not, we probably should continue this (ie, support for your research) in email, as WP Talk pages aren't really meant for such things. My email address is usable from WP. ww 14:43, 29 Jun 2004 (UTC)

[edit] Clarification on JN-25 Fabrications

Sigh, as usual I failed to make the question specific enough.

To be a bit more specific: somebody put comments on the Enigma article about fabrications concerning British codebreaking operations. I am trying to find the person who made the comments and obtain a general idea of what statements were fabricated and who did the fabrications.

Do I believe that anybody had cracked JN-25 and knew about Pearl Harbor? The idea is silly on the face of it, and no persuasion is necessary on that count.

Greg, Oh well... The fabrications that were meant probably refer to Rusbridger and his book, and allegations that either derive from it or which have circulated independently in the hidden history of Pearl Harbor community. As nearly as I can make out, many (most?) of these are not easily traceable. You've heard about the 100mpg carburettor that GM (or Standard Oil, I can't remember which) bought up and put on the shelf, of course. Urban legends and their surburban and rural and seagoing counterparts are quite hard to trace. ww 14:05, 1 Jul 2004 (UTC)

[edit] comment on 28 July ver of todo list

This is a long article, though shorter than it was since much material was removed to Ultra. Several of the todo suggestions here have the effect of adding material which, though interesting, will not add to a reader's overall understanding. They are in significant respect a sort of inside baseball, of interest only to fanatics (in this case, cryptiacs, I suppose). Eg, Zygalski sheets (there was a different name used at BP, but I can't bring it up just now; Clifford?), Hervel tip, indicator systems, Banburismus, rodding, and so on. If these should be in WP, and I can certainly agree that they should be, they shouldn't be here, but rather in a separate article -- Breaking Engima or something similar. jwr's comment (above) is relevant, and definitive on this degree of detail, in this article, I think. He at least doesn't have a cryptiac's bias.

As for trimming the disclosure section, I think this is a different kettle of fish. (Not Lorenz fish either). There is a considerable degree of bumpfh in the available literature in and around Enigma, its nature, its operation, its cryptanalysis, and the uses and significance of its output. Some of this is from close participants (Winterbotham on the distribution side), (the story about the Polish underground's ambush of a truck carrying an Enigma -- in Gordon Welchman's Hut Six account and elsewhere), and so on. The reasons for this include governmental secrecy, staged release of information formerly secret, deliberate misinformation, ... Our Gentle Reader should be informed of this, as it is central to the subject, and knowledge of the subject. Just where and how this should happen is another question I think. This section is somewhat jarring as it is about Enigma from another perspective than the rest of the article, but how better to do this is not clear. We have a responsibilty to our Gentle Reader which requires something along these lines. We will not have a better example from contemporary crypto for, presumably, some years (decades) yet. ww 16:25, 28 Jul 2004 (UTC)

We need balance. There's something wrong if we have a page long section describing how the Enigma story was revealed and fail to mention the various methods used to break the Enigma by the allies; the story itself is more central than how the story was first told. I'm certainly not suggesting we have pages and pages explaining exactly how each individual method works, but an overview of the cryptanalysis is essential. We can't assume that the "Gentle Reader" is a layperson, or not interested, or anything of the sort. I suggest we add everything; sections which seem too detailed or minor will obviously suggest themselves as candidates for being summarised and split off into separate articles. — Matt 22:26, 28 Jul 2004 (UTC)

[edit] Need to clarify

Versions of Enigma were used for practically all German as well as much of the European Axis' radio, and often telegraph, communications throughout the war; even weather reports were encrypted with an Enigma machine. Both the Spanish during the Civil War and the Italians during World War II are said to have used one of the commercial models, unchanged, for military communications. This was unwise, for the British (and presumably others) had succeeded in breaking the plain commercial version(s) or their equivalents.
It is estimated that between 100,000 and 200,000 Enigma machines were constructed during World War II. The Japanese are said to have obtained an Enigma machine as early as 1937, although whether they were given it by their German allies, or bought a commercial version which, except for the plugboard and the actual rotor wirings, was essentially the German Army / Air Force machine, is disputed.

We should clarify language like "are said to" and "presumably". Particularly, can we say for certain that the Spanish and Italians used commercial Enigma during WWII? And did the Japanese obtain an Enigma machine as early as 1937? If we can't be certain, we should specify exactly who it is who has speculated along these lines. — Matt 03:18, 29 Jul 2004 (UTC)

Matt, On the question of whether the Japanese had an Engima machine, I have seen a picture of what is claimed to have been a Japanese-built Engima with the rotors arranged horizontally (ie, edge on) instead of face to face as in the Engima. Very nice workmanship apparently. Whether compatible with German military Enigma or not I haven't heard. And I have come across several mentions of Enigmas (presumed from context to be military ones) being shipped from Germany to Japan late in the war but sunk. The 'U-boat supply line' thing, if you remember. Ores and such were planned as well if my understanding is correct.
I think I would leave the 'said to' and 'presumably', weasel words though they may be, as more detailed (ie, credible) information is scarce on the ground I'm familiar with, and on the basis that there are rumors floating around (in much published material, not merely urban legend quality stuff) whose existence and content should be, at least inferentially, acknowledged. We should not leave the bushwa (well meant or not) accounts of this history unaddressed.
As for versions being used... SD, Army, Navy, Air Force, Abwehr, Italian Navy, all(?) in multiple networks, all used Engima of one sort or another. This is pretty heavy use of one (albeit variants and in multiple networks) machine. The claim is not cast in precise language and the authorial arts of allusion and such do have a place somewhere, in your view, do they not? They do in mine, as I regard the point to be understanding gained, not only hard information passed.
Finally, we are back up to 39K even after removals to Ultra. There's a limit to the amount of detail we can put in this article. I'm not quite sure where it is, but surely.... ww 16:11, 29 Jul 2004 (UTC)

[edit] Comments

I did not read the entire article, however I read a large majority of it and I would like to say that as far as grammar goes it is superbly written! Jaberwocky6669 03:33, Jul 29, 2004 (UTC)

J, We're getting there. Sort of. Fascinating to see that there are >= 6668 other Jaberwockys here on WP. ww 16:16, 29 Jul 2004 (UTC)
  • Lol, I just like to use the number because it makes the name completely senseless. By now I am sure we have 7,000+. Jaberwocky6669 00:31, Jun 26, 2005 (UTC)

[edit] French Enigma work

Matt, re your recent reversion in re French Engima work. Should be reversed.

After Poland fell and the Biuro folk were evacuated, they (Rejewski et al) were installed in Paris (and then after the Fall of France at PC Bruno (the British seem to have been reluctant to let them into BP -- but that's only a construal of mine from the odd comment here and there) and the French (under Bertrand) and BP proceeded to work together on Enigma. This was early days for post three_letter_indicator Army Enigma cryptanalysis and the Poles were the world experts at the time. Indeed the only experts anywhere, discounting any playing along by Divine observers. As Turing and crew got up to speed (and addressed Enigma aspects the Poles had taken a pass on, ie Naval Enigma), BP took on more and more of the strain, especially after PC Bruno was shut down. For a while there was a shared work schedule between Fr and BP (and I recall especially between BP and Bruno) and there are records of frustration at BP waiting for the French to (break into this or that was the basic issue I guess).

That France fell has distorted all our impressions of the contributions made before (and after, for that matter) by them. Gamelan is not an outstanding aspect of those contributions, of course, nor Petain nor the Vichyites generally, but... In this case, it is clear that the sequence was 1) nobody (Naval Enigma as Brits and French gave up on it), 2) Poles at the Biuro (between '32/33 and '39 for early Army Engima), 3) jointly French (in Paris and then PC Bruno w/ assistance from evacuated Poles) and BP (on Air Force and Army Engima), 4) after PC Bruno shut down BP alone (all Enigmas), until 5) US began to help at BP after the political pushme pullyou struggles died down, and then finally 6) as US bombes were built and delivered to BP and the girl's schools in Washington, BP and US.

Having reread this just now, I am struck by something I think I've never considered before. Were pre fighting Luftwaffe Engima operations as readable as they were later (relatively, anyway)? And did the Biuro have a run against them or any success? Was there any traffic to be read? Not much of the organizational variety as there were no forward bases prior to Sept 39, but surely there was some wireless traffic? There was Army wireless else the Biuro wouldn't have had much to work on. Or was it intercepted (tapped) telegraphic stuff? Do you know anything? Anyone??

Anyway, I trust this clarifies the motivation behind the edit I made to include the French? Will you restore, or shall I? ww 19:02, 29 Jul 2004 (UTC)

I've restored the "In France"; I queried it because I remembered that some mention of the Poles after Poland not being allowed to work on Enigma, and consigned to some lesser ciphers instead. It seems that they did, indeed, continue work on Enigma in France (I found a few references to an "Equipe Z" operating between 1939 and 1942 [3]) — Matt 22:22, 29 Jul 2004 (UTC)
Matt, An interesting reference you have turned up. It would appear from that that EquipeZ was in fact PC Bruno under a cover name. The dates and circumstances match well enough to make this plausible. But I've never heard the name before. More importantly however, they claim --for the first time I have ever seen -- that the Buiro had broken into German Naval Enigma, and furthermore that they did so before the break in the Army Enigma. This raises a few questions I'm currently ill equipped to investigate as my reference material is inaccessible for the moment.
Is this true, or another of the not so reliable factoids about Enigma and its history (and crypto history generally) that this site notes in its opening para?
If true, which Naval Engima is meant? The first version (adopted in '27(?)) did not use a stecker and was abandoned when the Army adopted its version some years later (with a stecker). My impression had been that this was due to efficiency (economies of scale in manufacturing I suppose), with perhaps some input from army crypto studies about increased security of the stecker version. But perhaps the primary concern actually was security?
The claim is made here that all three Polish musketeers were involved in the first break. This does not square with my memory of most (credible) accounts nor with my memory of Rejewski's own account. In those, the first break was made by Rejewski who was working independently and was done on the famous fundamental mathematical basis. Only then were the others called in. Furthermore, the first breaks into (whichever) Engima required additional clues which came from the message setting procedure (three operator chosen letters repeated twice) which was, it is my understanding, never used by the Navy at any time.
I contribute these questions for further study without, alas, answering them. Perhaps, if there is an embryonic urban legend here, we might scotch it early. Or, if true, improve our knowledge and WP content. ww 14:28, 30 Jul 2004 (UTC)

[edit] Comment from WP:FAC

If you're more worried about length, then maybe the article should be separated into one on the machine itself (which the article title is anyway) and one on the process of breaking the cipher. You guys seem to have a lot more material to go in, so it would be a shame to not do that just because this article should really only be about the machine anyway. - Taxman 20:53, Jul 29, 2004 (UTC)

Perhaps. There's a number of threads to the Enigma topic, and it is proving difficult to fit them all in: 1) A description of the workings and components of the machine; 2) A history of how the machine was developed and evolved, and who used it; 3) The techniques for codebreaking; 4) The history, people and results of the codebreaking (Ultra); 5) How the Enigma story was revealed 30 years (or more) later. As you suggest, perhaps we should stick primarily to 1) and 2) within Enigma machine, and evolve off the other parts into separate articles (I think User:ww also suggested splitting of the cryptanalysis details); of course, we should leave a paragraph or two for each of 3), 4) and 5) to summarise. Actually, maybe this comment should be on the Talk: page... — Matt 21:15, 29 Jul 2004 (UTC)

[edit] Nice work

Wow, nice work on this article at the end of the FAC process. Great details added and important extra info moved off to its own article. The diagrams are great. Keep working on the todo list, and I'm sure this will get even better. - Taxman 23:14, Aug 2, 2004 (UTC)

[edit] still Trouble in River City

I've recently noted that the 2005 Mathematics Calendar (they publish them early here in the US -- probably some kind of New World plot, of course) discusses (though briefly) the Enigma code from WWII. Sigh... ww 20:06, 30 Aug 2004 (UTC)

And we may note that some of P G Wodehouse's characters, whatever their other virtues, have troubles too. In Right Ho, Jeeves, there may be found a wire from Augustus Fink-Nottle in response to one from B W Wooster.

Cipher telegram signed by you reached me here. Reads 'Lay off the sausages. Avoid the ham.' Wire key immediately. Fink-Nottle

We may note here that the wire sent which evoked this was almost certainly not a either a cypher (which might require a key to understand, perhaps especially amongst Bertie's crowd) nor a code, for we are given the reasoning which produced it earlier in this work. But, not knowning that, as Fink-Nottle did not, it is unreasonable to assume it to by a cipher as these rarely produce intelligible (well, in this case the question is perhaps open...) output. This wire is, if anything clandestine, a code, and Fink-Nottle's request for the key was simply wrong. Fink-Nottle has here, erred in the same unfortunate sense as does the 2005 Mathematics calendar, and many articles here on WP. I've certainly not caught all misuse, I'm sure.

As for those in a quiver to learn the outcome of the Fink-Nottle wire, Bertie responded with

Also kidneys. Cheerio. Bertie.

Which clarifies all, of course. ww 19:35, 18 Sep 2004 (UTC)

[edit] Rejewski removal

(For context, here's my original edit summary: I don't think there's room to mention Rejewski here (else, it'd only be fair to mention Turing, and then...); also, Rejewski's attack depends on procedural flaws anyway) — Matt 12:38, 19 Sep 2004 (UTC)

Matt, I would disagree as user procedural errors were incidental to his use of maths in the initial analysis. His insight was able to use them, but was independent of them (though perhaps stimulated by them)

Not at all; procedural flaws and operator error were integral to Rejewski's recovery of the wiring — these were, specifically, the doubly enciphered indicator, the use of a global ground setting and the non-random choice of indicators. These factors were quite separate to weaknesses in the Enigma cipher itself. Rejewski exploited all these weaknesses by using theorems about the cycle structure of permutations. — Matt 12:38, 19 Sep 2004 (UTC)
Matt, Just noticed your comment. My memory of his work is different than yours seems to be. His application of group theory and pure math to Enigma analysis was not a result of operator or procedural errors on the part of the Germans. That was his particular contribution, and it covers him and his memory with cryptanalytic glory. That, having done such an analysis, one is faced with finding daily (weekly, monthly, .. I can't remember when they changed around) keys which is rather less ethereal proposition, for which perforated sheets (in the Zygalski implementation) and cyclometers and bombas (first editions) and so on are needed. Less historic distinction there, more workaday stuff, I suppose. ww 20:54, 16 Oct 2004 (UTC)
By procedural error, I mean the use of a flawed indicator system. By operator error, I mean the use of non-random indicators. Rejewski's method, as described by Rejewski, exploited both of these weaknesses. If you like, I can give you quotes from his paper. — Matt 22:08, 16 Oct 2004 (UTC)
Matt, We are here talking about different things. I am concentrating on the theoretical analysis by Rewjewski, and you are considering the problems of decrypting messages from particular networks (ie, procedural commonalities). I see no disagreement with what you've said, but with its scope. ww 19:54, 19 Oct 2004 (UTC)
No, I'm afraid I'm not talking about decrypting particular messages. I'm talking about the initial theoretical analysis by Rejewski, the one which used mathematical theorems about permutations and which he used to recover the wiring of the rotors. In particular, Rejewski — in his 1980 paper, "An application of the theory of permutations in breaking the Enigma cipher" — relates how he decomposes the permutation products AD, BE and CF into A, B, C, D, E and F. A mathematical theorem gets him close, enough to whittle down the choice to "several thousands or several tens of thousands [of] possible solutions". To complete the decomposition, he uses the fact that operators choose guessable indicators, such as the same letter repeated "lll". This was the operator error. The procedural flaw was to use doubly enciphered indicators at all (and a common ground setting); if this was not used, Rejewski's method wouldn't even have been applicable. The paper is available online, as well as some explanatory lecture notes, at Frode Weierud's pages: [4]. — Matt 22:44, 19 Oct 2004 (UTC)

I too have the impression that Rejewskis success was to a large extent the result of german mistakes. But then, R needed to exploit the fastest way into enigma for effiency reasons, which was enabled infrequent key change asf.. The enigma hardware could have been kept practically unbreakable, had the germans had operated it the best way. It was still attackable, but the effort against "best play" might have been higher than the allied could have mustered (without capture asf.). also Rejewski writes, the germans would have been better off with no message key at all, let alone repeated 2x3 key. I mean Rejewski had rather little practical choice, if he saw a flaw, he expoited it to the full, whether or not his reputation as a "pure mathematician" suggested a more scientific approach independent of op. flaws. 83.129.26.203 22:08, 30 Jan 2005 (UTC)

He deserves mention in prior to Turing fo rthis reason. Turing's insight in re Naval Enigma was also quite good, but was found in the midst of actual Enigma work. Rejewski was working in isolation, was first, and had no context within which to work. Comment?199.97.121.99 19:50, 18 Sep 2004 (UTC)

This is in the context of the lead section of the article. The lead section provides a summary of the rest of the article, and it's preferable to omit the details at this stage; we're simply providing the reader with a sweeping survey. If Rejewski dominated the story of the Enigma, it might be necessary to mention him in the lead section, but I think it's clear that, although his contribution was outstanding, he does not play this type of role. From this "distance", it suffices to say that the Germans used the Enigma, and the Allies broke it, and that this was significant. The details can wait till later.
Also, this article is primarily about the machine itself, the history, the different versions, a description of how the different parts fitted together, a formula describing the encryption. Cryptanalysis of the Enigma is our main article about the Enigma codebreakers, although we do have a (rather inadequate) summary section here in this article ("Breaking the Enigma — Ultra").
As an aside, regarding the relative "importance" of Turing and Rejewski, I'm not convinced such an analysis is profitable. Turing's primary Enigma "insight" was the Bombe, and this was used for most Enigma traffic, not just Naval. (His most prominent contribution to Naval Enigma was the "Banburismus" procedure.) Without Turing's Bombe, Bletchley Park wouldn't have read even a twentieth of the traffic that they did after May 1940 (when the double-indicator system was changed). — Matt 12:38, 19 Sep 2004 (UTC)
Matt, Again, I've just noticed this. And again, my memory diverges from yours. The Turing bombe design was indeed a considerable advance, but was nevertheless firmly based on Polish work. The diagonal procedure of Welchman was new however. But Turing's work on Enigma was not limited merely to a bombe design or Banburismus, but on the entire mathematical structure of the beast. Here he appears to have been following Rejewski in spirit if not in detail. I'm not very clear at all about how much of R's work at this level was passed on to BP. Turing was director of the Naval Enigma work in Hut (Six -- my memory persistenly reports this as the Naval Hut) and Welchman was his nr 2 when he came up with the diagonal business. Turing was more important, I think, than you suggest and in more ways. But R still made **the** breakthrough. ww
There is no evidence (as far as I'm aware) that the Turing bombe design was firmly based on Polish work. We can at best speculate as to what inspiration there might have been, but the end results — the attacks that the machines implement — have only superficial similarities...the name and the fact that they mechanise the finding of the rotor start position. But the cryptographic attack that they mechanise is completely different, and the actual machines are completely different. (It is hut eight). — Matt 22:08, 16 Oct 2004 (UTC)
Matt, Without access to my notes and materials, I will have to leave things as they are on this point. ww 19:54, 19 Oct 2004 (UTC)

[edit] Congratulations on being featured!

Soirry I could not help with this article, but it looks extremely good, and is a good ambassador article for wikipedia. Well done everyone, especially Matt. Rich Farmbrough 10:26, 13 Oct 2004 (UTC)

Cheers! You are, of course, very welcome to see if this article could be improved further (I'm sure it can), and there's a bunch of other World War II-era crypto pages that are in dire need of some attention if the subject tickles your fancy (see also World War II cryptography, *gulp*)...! — Matt 10:45, 13 Oct 2004 (UTC)

thanks to everybody who contributed to this awesome piece of work. i stumbled into the page on a lark yesterday, and it's been a blast for many hours. this and the related articles are top notch. thanks! SaltyPig 15:45, 22 Apr 2005 (UTC)

Thanks for the kind comments! — Matt Crypto 15:53, 22 Apr 2005 (UTC)

[edit] Backwards compatibility?

Were any of the various models backwards compatible? Or did units (and submarines, and ships) get upgraded and then somebody back at HQ had to remember which machine to use to transmit to them? Tempshill 17:23, 13 Oct 2004 (UTC)

There was some consideration for backwards compatibility. In particular, the four-rotor Naval Enigma, used by the U-boats, was designed so that if the fourth rotor was placed in one of the 26 positions then the machine operated exactly like a three-rotor machine. Still, HQ had to remember exactly who they were transmitting to — by the end of the war, there were a large number of networks each using completely different daily settings, even though the Enigma machines were the same. — Matt 22:56, 13 Oct 2004 (UTC)

[edit] SecurityFocus cite

On 01 Nov 2004, this article was cited in a SecurityFocus article on phishing. Securiger 06:49, 8 Nov 2004 (UTC)

[edit] Definition of 'offset' on rotors and ringsettings

I noticed that many people want to simulate the Enigma but are confused about how the ringsettings works exactly, the direction of the ringsettings (wiring), relative to the rotor and notch etc...

The Offset

As example, let us take rotor type I without any ringsetting offset. You can see that an 'A' is encoded as an 'E', a 'B' encoded as a K, and a 'K' is encoded as an 'N'. Notice that every letter is encoded into any another.

In case of the reflectors, we take Wide B where an 'A' is returned as a 'Y' and the 'Y' is returned as an 'A'. Notice that the wirings are connected each time as a loop between two letters.

When a rotor has stepped, you must take in account the offset to know what the output is, and where it enters the next rotor. If for example rotor I is in the B-position, an 'A' enters at the letter 'B' which is wired to the 'K'. Because of the offset this 'K' enters the next rotor in the 'J' position.

The ringsetting

The ringsettings or 'Ringstellung' are used to change the position of the internal wiring relative to the rotor. They do not change the notch or the alphabet ring on the exterior. Those are fixed to the rotor. Changing the ringsetting will therefore change the positions of the wiring, relative to the turnover-point and start position.

The ringsetting will rotate the wiring. Where rotor I in the A-position normally encodes an 'A' into an 'E', with a ringsetting offset B-02 it will be encoded into 'K'

As mentioned before these encodings only happen after the key is pressed and the rotor has turned. Tracing the signal on the rotors AAA is therefore only possible if a key is pressed while the rotors where in the position AAZ.

Rotor wiring tables

Rotors Kriegsmarine/Wehrmacht/Luftwaffe (3-rotor model)

I = EKMFLGDQVZNTOWYHXUSPAIBRC

II = AJDKSIRUXBLHWTMCQGZNPYFVOE

III = BDFHJLCPRTXVZNYEIWGAKMUSQO

IV = ESOVPZJAYQUIRHXLNFTGKDCMWB

V = VZBRGITYUPSDNHLXAWMJQOFECK

Rotors used by Kriegsmarine only (3-rotor M3 and 4-rotor M4 model)

VI = JPGVOUMFYQBENHZRDKASXLICTW

VII = NZJHGRCXMYSWBOUFAIVLPEKQDT

VIII= FKQHTLXOCBJSPDZRAMEWNIUYGV

Zuzatzwalzen or Greek rotors used by Kriegsmarine. To be inserted before thin reflectors only.

Beta = LEYJVCNIXWPBQMDRTAKZGFUHOS

Gamma = FSOKANUERHMBTIYCWLQPZXVGJD

Wide reflectors Wehrmacht/Luftwaffe

Reflector B = YRUHQSLDPXNGOKMIEBFZCWVJAT

Reflector C = FVPJIAOYEDRZXWGCTKUQSBNMHL

Thin reflectors Kriegsmarine

Reflector B Thin = ENKQAUYWJICOPBLMDXZVFTHRGS

Reflector C Thin = RDOBJNTKVEHMLFCWZAXGYIPSUQ

Drdefcom 18:34, 4 Dec 2004 (UTC)

Dr, Just noticed your magesterial info here. In a regular encyclopedia, this might be 'too detailed'. In WP, I think we need to find a place in one of the Enigma articles for this material. Ideas, anyone? Please keep in mind that, even in a WP table or some such, this is a lot of detail so I think we'll have to be careful to include it gracefully, whereever and however it's gets put in.
Great work, Dr! Thanks. ww 00:45, 10 Dec 2004 (UTC)
Thanks! Well, all ideas are welcome. I would suggest a new page with a very breef intro on enigma and why this page. For those who don't understand what the hell it is, we could direct then to Enigma. Anybody other ideas ?? Dirk 19:19, 10 Dec 2004 (UTC)
Brainstorming here, so bear with me! OK...On DES, we have DES supplementary material, which contains some reference material; maybe something like that could work for Enigma machine? It does occur to me, though, that a lot of information on this page verges towards being too detailed at times. This is not a problem as such (more an advantage!), but it suggests that we could apply "Summary style", which means we would factor out various sections into sub-articles, and replace them with summarised sections, so there could be a History of the Enigma machine to discuss the development of the various commercial and military versions. There could be a Technical description of the Enigma machine, or some such. There could be a Procedures for using the Enigma machine, as well, as we only include one out of many indicator schemes. — Matt Crypto 20:09, 10 Dec 2004 (UTC)

[edit] Table in progress

Rotor Wiring
I EKMFLGDQVZNTOWYHXUSPAIBRC
II AJDKSIRUXBLHWTMCQGZNPYFVOE
III BDFHJLCPRTXVZNYEIWGAKMUSQO
IV ESOVPZJAYQUIRHXLNFTGKDCMWB
V VZBRGITYUPSDNHLXAWMJQOFECK
VI JPGVOUMFYQBENHZRDKASXLICTW
VII NZJHGRCXMYSWBOUFAIVLPEKQDT
VIII FKQHTLXOCBJSPDZRAMEWNIUYGV
Beta LEYJVCNIXWPBQMDRTAKZGFUHOS
Gamma FSOKANUERHMBTIYCWLQPZXVGJD
Reflector B YRUHQSLDPXNGOKMIEBFZCWVJAT
Reflector C FVPJIAOYEDRZXWGCTKUQSBNMHL
Reflector B Thin ENKQAUYWJICOPBLMDXZVFTHRGS
Reflector C Thin RDOBJNTKVEHMLFCWZAXGYIPSUQ
Here's the storm in my (little) brain. The problem with the approach of sub-articles is that the article itself may not water down to a table of content. The mainpage should have enough information and story to catch te reader. Too much info isn't good, but too little neither. The difficult part then, is to select what, and how many there's to be send to the sub. Sending interesting pieces to the sub could harm the article. My my, it's difficult Dirk 10:28, 12 Dec 2004 (UTC)
Ay, there's the rub. Shakespeare said, or should have. The cryptiac group has been 'rasslin with this for some time. See for instance, the talk history at cryptography, at the WikipediaProject Cryptography, at secret sharing, and elsewhere. It is, I think, an eternal question for which the situation seems to preclude a definitive answer. Consider only the cypher v cipher spelling question!
Withall, and wherever it gets put, you're doing good work. Re congrats. ww 20:43, 16 Dec 2004 (UTC)
The subarticle on rotor details is a fact! Since I'm not that experienced in Wiki, i have a question: Maybe the "Enigma rotor details" can be 'part of the Enigma article' as shown in the blue box on the top right of the enigma article, but i have no idea how this is done...
PS: thanks to the person who changed the wiring table into a real table. Now I know how that works ;-) Dirk 12:16, 18 Dec 2004 (UTC)
Good stuff! The blue box is implemented using a "Template"; in the wikicode for Enigma machine at the top there's a little snippet {{EnigmaSeries}}. Basically, templates allow you to include one page directly into another; so in this case, the contents of Template:EnigmaSeries are copied into Enigma machine automatically by the Wikipedia software. So, whenever you see {{Foo}}, you can edit it by visiting Template:Foo; there's more detail at Help:Template. In this case, I've added an "edit this box" to make it a little easier. — Matt Crypto 15:06, 18 Dec 2004 (UTC)

[edit] History and movies

Why were my brief critiques of the two Enigma-related movies deleted? Citing, without due comment, fictional misrepresentations of history is tantamount to a tacit approval of disinformation. It's all right to say that an Enigma machine used in one of the movies is authentic—but not that the whole premise of the movie is a fabrication? Logologist 15:40, 8 Feb 2005 (UTC)

I removed them because I think it's too much detail for this topic; by all means include this information in the U-571 article or the Enigma (2001 film)/Enigma (novel) articles. It's OK to briefly cite notable examples of where Enigma crops up in fiction from time to time, but launching into reviews about the historical authenticity of this or that film seems — at least to me — to be drifting off-topic. Here, we're focused on details about a specific piece of electromechanical equipment. — Matt Crypto 16:03, 8 Feb 2005 (UTC)

[edit] reordering the "in combination with" section?

".. only their combination with other significant factors which allowed codebreakers to read messages: captured machines and codebooks, mistakes by operators, and procedural flaws. "

Most references I've read downplay the importance of captured gear and emphasize usage errors. Usage generally improved over the course of the war, but the codebreakers kept pace with the improvements and used their knowledge of usage patterns learned from previous breaks to help them get through process changes.

To this day, usage errors remain the primary way system designers hurt themselves with ciphers.

How about:

".. only their combination with other significant factors which allowed codebreakers to read messages: mistakes by operators, procedural flaws, and the occasional captured machine or codebook."

Thoughts? --Sommerfeld 22:45, 2005 Feb 10 (UTC)

Sounds good to me. The impression I get is that while captured material was useful for making entries into difficult systems (like Naval Enigma, for example), most of the day-to-day codebreaking was greatly eased by constant operator errors — predictable cribs, cillies, etc. — Matt Crypto 23:08, 10 Feb 2005 (UTC)
Done. --Sommerfeld 02:53, 2005 Feb 12 (UTC)

[edit] Surviving Enigmas

I saw survived Enigma in Museum of Science in Boston, Massachussets. Please someone add this info.

Thanks for the info; perhaps you'd like to add it to this wiki instead? There's too many Enigmas on display around the wolrd to list them all in this article. — Matt Crypto 18:17, 19 Mar 2005 (UTC)

[edit] Hi-res Photo

I just came across this article and noticed that the NSA photo is fairly low-res. I have uploaded a hi-res photo that I have released into the public domain at Image:EnigmaMachine.jpg, and also a labeled version at Image:EnigmaMachineLabeled.jpg. K. Sperling 01:52, 2005 Apr 15 (UTC)

Great photo, and thanks for taking the trouble with the labels! — Matt Crypto 02:15, 15 Apr 2005 (UTC)

[edit] Comment

re. the following 'sentence' in the first paragraph: "Allied codebreakers (see Biuro Szyfrów, Poland and Bletchley Park, England) were able to decrypt a large number of messages that were protected by the machine before being broadcast by radio".

I do not understand how the messages were 'protected' by the machine... Could someone explain, or clarify the sentence? Duncan.france 02:02, 30 Apr 2005 (UTC)

It would probably clarify the meaning of the sentence to replace "were protected by" with "had been enciphered on." logologist 04:12, 30 Apr 2005 (UTC)

[edit] Comment re. caption of image (1)

Caption starts: "Enigma encryption for two consecutive letters ...".

It might be useful to have an explanation of the greyed-out circuits in this illustration, e.g. (perhaps):

"The greyed-out lines represent possible circuits within each rotor, which are hard-wired to button contacts" (or are they bushes?) "on each rotor". Duncan.france 02:24, 30 Apr 2005 (UTC)

i think the recent changes are far too wordy, and even confusing/misleading. it's a diagram. would like to see it put back to 00:18, 2005 Apr 30. anybody interested enough can easily figure it out from the excellent article text, which the image is meant to illustrate, not replace. i was recently a first-time visitor, and i got it immediately -- probably better because there wasn't a bunch of extra text to parse. with the new text, i might actually have wondered briefly if the "A" always cycles between "G" and "C". SaltyPig 02:39, 2005 May 1 (UTC)

[edit] Enigma machine pic needed?

I think Image:Enigma1.jpg is not needed, as we already have plenty of images of the Enigma already. It's essentially a black-and-white version of the first picture — what additional information does it provide? Moreover, the image is non-free. I think the article would be better off without it. — Matt Crypto 17:44, 18 August 2005 (UTC)

It would be nice to have a pic of the Polish duplicate, though. I believe there is a Polish Enigma replica on display at the Polish Institute and Sikorski Museum in London. Next time I'm passing through I'll try and get a photograph that we can use. — Matt Crypto 19:35, 18 August 2005 (UTC)

[edit] Mathematical description

Isn't P = P − 1 (since the plugboard just swaps pairs of letters)? Also, permutations are normally written the other way, i.e. AB is "A after B", not "A then B", so both formulas should be reversed. --K. Sperling (talk) 11:30, 19 August 2005 (UTC)

Thanks for your formatting touches on this article! Yeah, P is its own inverse. I suppose I thought it would help people understand that it was going back through the plugboard "the other way" if I wrote the inverse sign, even though it's superfluous. Do you reckon we should change it? I believe you can write composition of functions in both left-to-right and right-to-left orders. The order in the article is the one used by Marian Rejewski in his paper on the Enigma, but we can certainly can write it the other way if you think it would be clearer for people. — Matt Crypto 11:50, 19 August 2005 (UTC)
Yeah you can of course write it both ways, and the left-to-right way is probably more intuitive for the casual reader. It does feel a bit odd if you're used to the way operators are stacked up in linear algebra though, which is right-to-left. Maybe we can expand the section a little, say that P = P − 1 etc., and link to some more of the relevant maths articles. I'll probably look into it next week. --K. Sperling (talk) 12:26, 19 August 2005 (UTC)

[edit] Enigma Uhr (clock)

I added the Wehrmacht & Luftwaffe procedures and a small piece about the Uhr. However, a nice free available picture of the Enigma Uhr (clock) would be nice. Anyone?Dirk 18:15, 29 September 2005 (UTC)

There's a couple on display at museums in the US: National Cryptologic Museum and the Museum of World War II, although the latter is not open to the general public. Maybe we should put a request up on the request for photos page (wherever that is!). — Matt Crypto 16:35, 19 October 2005 (UTC)
I've found one, courtesy of Austin Mills! — Matt Crypto 19:02, 5 January 2006 (UTC)

[edit] Inline references

This article was featured a year and a half ago, but now looks a little underreferenced by current Featured standards. It'd be good to liberally add inline cites. — Matt Crypto 18:15, 27 January 2006 (UTC)

[edit] Swiss Enigma K photo caption

What a superb article. Well done.

I would only suggest one small change: the word "submitted" in the caption for the Swiss Enigma K photo doesn't make sense; could it perhaps mean, "shipped" instead of "submitted"?

-elf

Thanks for your comments! I've tweaked the caption (and feel completely free to make your own alterations if you're so inclined). — Matt Crypto 13:40, 26 February 2006 (UTC)

Schussel is the German (Deutsche) word for key....or in this case cypher.

[edit] Wehrmacht addition of rotors -- when?

The article now claims that Wehrmacht Enigma procedures went to 3 of 5 rotors in December 1939. I suspect that this datum is wrong, if only because the Poles were having serious trouble near the beginning of that year, but can't remember the correct one. My references are not available, so I'll just suggest that it might have been 1938 instead. Maybe someone knows, right off the top of his/her head? ww 08:31, 14 March 2006 (UTC)

I'm afraid I can't tell you off the top of my head (maybe it means I have a life? maybe...), but Hugh Sebag-Montefiore gives the date as 15 December 1938. — Matt Crypto 08:42, 14 March 2006 (UTC)
December 15, 1938: see, e.g., bottom of Bomba (cryptography) article. logologist|Talk 06:20, 22 March 2006 (UTC)

[edit] Enigma key size

Does the following seem right?

Calculation of the number of inital settings would that be possible for an M4 enigma given 13 Stecker cables, 1 Each of the eight M4 Naval wheels (I-VIII), both of the UKW, and both of the greek wheels.

Wheel choice and position (main 3):  8 \times 7 \times 6=336
Wheel choice (greek) : 2
UKW Choice : 2
Ringstellung (all four wheels) 264 = 456976
Inital postiton (all four wheels) 264 = 456976
Number of combinations for Steckerbrett:\sum_{y=0}^{13} {\frac{\displaystyle{\prod_{x=1}^y {{ n - 2 \left ( x - 1 \right ) \choose 2}}}}{y!}}=532985208200576
Total: 336 \times 2 \times 2 \times 456976 \times 456976 \times 532985208200576=1495895333843842833367059922944
which is a key size of \log_2 (1495895333843842833367059922944)\approx96.9169239911

67.76.242.36 01:28, 7 June 2006 (UTC)

[edit] first sentence phrase

The first sentence included a link to some context, and immediately allowed a reader to understand some context even without following the link. A small, but useful virtue, hence the reversion. Reactions? ww 05:32, 2 July 2006 (UTC)

It was Poles who cracked the enigma machine, time to rewrite the history books.

Retrieved from "http://en.wikipedia.org../../../e/n/i/Talk%7EEnigma_machine_ac90.html"