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Colossus has been Rebuilt 279

Posted by CmdrTaco
from the no-not-the-one-in-sardia dept.
Max Driver writes "In celebration of D-Day, "Colossus", one of the earliest electronic code-breaking machines, has been rebuilt after ten years of effort by computer conservationists. Colossus was used to break the Lorenz cipher. This story is being reported by the BBC. Remarkably, the use of parallel processing (five tape channels) and short gate delay time (1.2 microseconds) allows the Colossus to match the speed of a modern PC."
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Colossus has been Rebuilt

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  • by Seumas (6865) * on Tuesday June 01, 2004 @08:23AM (#9302195)
    Phew. For a moment, I thought they were talking about this Colossus [imdb.com].

    An artificially intelligent supercomputer is developed and activated, only to reveal that it has a sinister agenda of its own
  • When I read the headline I thought it was about the Colossus of Rhodes!

    This is cool too :)
  • (sigh) (Score:5, Funny)

    by Lobo_Louie (545789) on Tuesday June 01, 2004 @08:24AM (#9302201)
    ... and the IRS still uses it to this day.
    • Not only that:

      [...] the use of parallel processing (five tape channels) and short gate delay time (1.2 microseconds) allows the Colossus to match the speed of a modern PC.

      ... but any day now some geek will announce that he's porting Linux to it.
  • Reminder: (Score:5, Informative)

    by JessLeah (625838) on Tuesday June 01, 2004 @08:26AM (#9302215)
    It only matches the speed of a modern PC at the single task it was designed for. Think of it as a very old, very interesting DSP. (I recall the stories on SlashDot about how the GPUs on modern ATI/nVidia cards are "many times faster than P4s"... well, yes, but you can't run Linux on them...)
    • by noidentity (188756)
      It only matches the speed of a modern PC at the single task it was designed for.

      Yeah, they're still trying to figure out how to make it crash as often.
      • They had to wait for Bill and Paul to "develop the first programming language [microsoft.com]" before that was even possible.
    • Re:Reminder: (Score:5, Informative)

      by Short Circuit (52384) <mikemol@gmail.com> on Tuesday June 01, 2004 @08:43AM (#9302295) Homepage Journal
      I recall the stories on SlashDot about how the GPUs on modern ATI/nVidia cards are "many times faster than P4s"... well, yes, but you can't run Linux on them...

      To elaborate:

      GPUs still only run at a couple of hundred of MHz, but their dedicated circuitry allows them to perform certain matrix calculations much faster than x86 chips currently do, even with vector instruction extensions like MMX and SSE/SSE2.

      Here are a couple of links to relevant articles. (1 [slashdot.org] 2 [slashdot.org])
      • GPUs still only run at a couple of hundred of MHz, but their dedicated circuitry allows them to perform certain matrix calculations much faster than x86 chips currently do, even with vector instruction extensions like MMX and SSE/SSE2.

        Which is why Apple [apple.com] and soon Microsoft [microsoft.com] with Longhorn (if they ever get around to shipping it) will be using graphics cards for a select number of display compositing tasks.

        It frees up the CPU, and can do it wayyy faster.

        -- james

        • Re:Reminder: (Score:3, Interesting)

          by Jeremy Erwin (2054)
          The quartz compositor treats each window's content, and each window as a openGL primitive. All Quartz Extreme requires is a certain amount of VRAM--32 is preferred, and the ability to support textures of arbitrary (not powers of two) height and width. As the Mac only supports a small number of video cards, this practically guarantees that a GPU will be available.

          But the GPUs in early nVidia and ATI cards are fixed function anyway-- useless for all except computing Transform and Lighting. Later models (GeFo
      • Which makes me wonder, if the dedicated instruction sets in your current GPU's were eventually to be included in a CPU, would this not be a major performance increase gaming-wise since it would eliminate the need for data to transfer through the PCI/AGP bus?

        Of course, the CPU's would have to be "gamer CPUs" since for standard non-gaming applications this would only be a lot of bloat.

        Isn't this somewhat akin to what 3dnow etc was supposed to be about?
        • You'd still need to transfer data through the AGP bus. More data than currently is done, in fact.

          Modern graphics cards assemble each frame from a collection of images, or textures, that are provided it. The GPU performs mathematical operations on these textures in order to orient them somewhere in the field of view.

          If you performed all of the operations on the CPU, you'd not only be taking up instruction cycles, you'd have to transmit entire frames through the AGP bus. 1600x1200x24bytes works out to ab
    • maybe... (Score:3, Informative)

      by lachlan76 (770870)
      I have seen a project to run programs on a gpu, with BrookGPU [stanford.edu].
      It would only be applicable for certain applications, but some of the things that a graphics card excels at (I think) are linear algebra, vector manipulation, and some other number-crunching activities.
      You can't run linux on it though, just programs written in Brook Stream language (an extension of ANSI C).
  • Just goes to show what can be done when you are clever about using what you have.
    • Neccesity is the mother of invention. If the fate of the world is at stake one can become very inspired.

      The challenge for each of us is to find a way to change the world with what we do.

      At the beginning of my career 14 years ago flying home from my first big interview I talked at length with someone on an airplane about a literature, travel, educational background etc. he summed up his career with "I sell sunflower seeds for human consumption" although someone needs to do it I suppose, sadly many of us sp

      • by Lodragandraoidh (639696) on Tuesday June 01, 2004 @09:55AM (#9302693) Journal
        If everyone did only what inspired them, alot of the unglamorous products and services we take for granted would not exist, and everyone's lives would be less for it (of course, I could do without my MTV, and the endless wasteland of product differentiation...)

        Some people don't have any aspirations beyond drinking beer and fishing, and no vision beyond determining what is for dinner. That is fine. Everyone has a purpose in the grand scheme of things, or if they don't, one will be issued to them at some point out of necessity. Perhaps raising children is their life's world-changing work, while their job is just that - a job to put food on the table. I know this might be a shock to you, but life does not have to center around your occupation; your occupation can be on the periphery.

        The really free, self actualized people are the ones living under the highway overpass in cardboard boxes. The rest of us do the best we can with what we have, and what necessity dictates.
  • good design (Score:5, Interesting)

    by millahtime (710421) on Tuesday June 01, 2004 @08:30AM (#9302237) Homepage Journal
    Remarkably, the use of parallel processing (five tape channels) and short gate delay time (1.2 microseconds) allows the Colossus to match the speed of a modern PC."

    This definitely shows you what a good design can do. WIth all the advancement I expected that thing to be slower than my TI-89 calculator.
  • A tragedy (Score:5, Insightful)

    by sql*kitten (1359) * on Tuesday June 01, 2004 @08:30AM (#9302239)
    From the article:
    After the war, most of the machines were scrapped to protect their sophisticated secrets.
    If the British Government hadn't been so short-sighted, the UK now would be the centre of the global computer industry. Aye, but they threw away aerospace too. Always, Britain invents, loses interest, and the rest of the world reaps the spoils.
    • Re:A tragedy (Score:5, Informative)

      by Polkyb (732262) on Tuesday June 01, 2004 @08:46AM (#9302311)

      I saw a documentary on this a few weeks ago... Apparently, all the parts that went into making the beasties was "borrowed" from British Telecom. After the war, they just gave the parts back.

      • Re:A tragedy (Score:4, Interesting)

        by meringuoid (568297) on Tuesday June 01, 2004 @08:51AM (#9302334)
        Apparently, all the parts that went into making the beasties was "borrowed" from British Telecom. After the war, they just gave the parts back.

        Reminds me of something I heard about the Manhattan Project, which was a similar exercise in rounding up every geek in the country and making them do cool secret stuff... Apparently they couldn't get the copper wire they needed for the electromagnets used in refining their uranium, so they just took all the silver out of Fort Knox and made it into wire. Melted the lot down after the war and put it right back, no harm done...

        Of course that makes me wonder what Auric Goldfinger was thinking of. America's loot stash is already radioactive! :-)

        • Re:A tragedy (Score:4, Interesting)

          by PapayaSF (721268) on Tuesday June 01, 2004 @01:33PM (#9305204) Journal
          You're almost right. They did get tons of silver (not all of it) to make electromagnets (not just wire), which were so huge and powerful that when turned on, people standing many yards away could feel the pull on the nails in their shoes and on their belt buckles!
    • Re:A tragedy (Score:5, Informative)

      by CdBee (742846) on Tuesday June 01, 2004 @08:46AM (#9302312)
      It was destroyed so other countries would never find out we could break their ciphers. It still needed to be secret after WW2
    • Re:A tragedy (Score:5, Insightful)

      by eggoeater (704775) on Tuesday June 01, 2004 @08:49AM (#9302328) Journal
      In one of James Burke's documentaries he talked about Britian basically "inventing" the fabric dying process (maybe in the early 1800s) but British industry never did anything with it. The Germans jumped on it and cornered the dying/fabric market, which bootstrapped their economy into the powerhouse it became until their defeat in WWI.
      So it does seem the UK has a track record here...
      • Britain invents, loses interest, somebody else commercialises, and then Britain still wins the war.

        How do those Brits do it?
        • Easy. Unless the invention is some major breakthrough in naval warfare the Brits don't loose interest.

          Since you need either boats or a well trained swim team to invade the UK they're good to go for the most part as long as they maintain naval superiority.

          That's why the battle for the Atlantic was so important.

        • Having a massive Empire providing income and troops didn't hurt.
    • OK, so we tossed away the computer, aerospace, and other industries.

      But look at the popularity of the ideas we exported; why, in central London a pub has a sign outside saying it was where the Communist Manifesto was launched, and offering themed lunches (borscht etc.) (oddly I can't remember a similar sign outside the hofbrauhaus in Munich). Who would have thought that would take off?

    • Re:A tragedy (Score:2, Interesting)

      by jdtanner (741053)
      Not the only thing us Brits have missed out on I'm afraid... The integrated circuit [bbc.co.uk] RSA encryption [theregister.co.uk] Doh!
    • Re:A tragedy (Score:2, Interesting)

      by Isofarro (193427)
      If the British Government hadn't been so short-sighted, the UK now would be the centre of the global computer industry.

      From the article, to get around the reliability of valves the solution with Colossus was to leave it on until the end of the war, so it would have been on from 1 February 1944 through to at least 15th August (surrender of the Japanese). That's a 18 month uptime.

      More uptime than the average Windows laden PC.

  • Free information. (Score:2, Insightful)

    by chuck54 (701897)
    This to me illustrates the need for free information. If information about this machine had been made public in the years after the war, we may now have been a good few megahertz ahead of our selves in computer technology.
    • Re:Free information. (Score:5, Interesting)

      by meringuoid (568297) on Tuesday June 01, 2004 @08:39AM (#9302279)
      If information about this machine had been made public in the years after the war, we may now have been a good few megahertz ahead of our selves in computer technology.

      I seem to remember hearing that a lot of Third World countries carried on using the German cryptosystems for a long time after the war, and that was why all the Bletchley technology was kept black - we rather liked being able to read everyone's mail. Don't know how true that is, though...

      IIRC, GCHQ also invented the RSA cipher years before it was discovered in the civilian world. Damn shame we didn't get to cash in on that one :-)

      • Re:Free information. (Score:5, Interesting)

        by ezzzD55J (697465) <slashdot5@scum.org> on Tuesday June 01, 2004 @09:11AM (#9302420) Homepage
        I seem to remember hearing that a lot of Third World countries carried on using the German cryptosystems for a long time after the war, and that was why all the Bletchley technology was kept black - we rather liked being able to read everyone's mail. Don't know how true that is, though...

        Well, there is something related here; Dennis Ritchie dabbles in cryptography [bell-labs.com]. He talks about cryptanalysis of the hagelin m-209b [iacr.org] crypto device (I bought one on ebay :)). They submitted their findings for voluntary review by the NSA before publishing, and Ritchie was visited by a "Retired Man" from the NSA. The relevant bit:

        He got a bit more specific about two things: the agency didn't particularly care about the M-209. What they did care about was that the method that Reeds had discovered was applicable to systems that were in current use by particular governments, and that even though it was hard to imagine that these people would find the paper and relate it to their own operations (which used commercially-available crypto machines), still... perhaps we should exercise discretion? It was certainly legal to publish, but publication might cause difficulties for some people in the agency.
        Full story in the first link.

        So, even though this has nothing to do with the UK and colossus/enigma/lorenz directly, it still is a similar story.

      • Brit RSA encrytion (Score:5, Interesting)

        by BlightThePower (663950) on Tuesday June 01, 2004 @09:41AM (#9302607)
        For more information see "The Code Book" by Simon Singh.

        It was developed by the superbly named Clifford Cocks, a at GCHQ in 1973 (IIRC thats three years before Rivest et al.) Apparently he thought it no big deal (completing an implementation of Ellis' original proof-of-concept practically overnight) and filed it away for further reference. End of story. Cocks is now chief mathematician at GCHQ; and given that he's probably intercepting this communication as I write, I dare say he will pop-up if what I've said is inaccurate!

        The true tragedy is obviously that RSA is called RSA, rather than the far more amusing "Cocks Encryption" or similar. The sheer weight of punnage (e.g., "Hard Cocks Encryption" anyone?) is a tragic is a loss to humanity IMHO.
        • Cocks is now chief mathematician at GCHQ; and given that he's probably intercepting this communication as I write, I dare say he will pop-up if what I've said is inaccurate!

          Well, yes, GCHQ have almost certainly logged this communication - as will Google in the not too distant future, so that's not so cloak-and-dagger... But I doubt the great man will actually turn up. More likely some large men will be coming around to explain to you why, if you're going to make fun of people's names, it's perhaps wise to

        • by Ernesto Alvarez (750678) on Tuesday June 01, 2004 @01:24PM (#9305041) Homepage Journal
          The interesting thing about britain's RSA was not the invention of the method itself. They knew it was theoretically possible to do public key encipherment early in the 1970s, but didn't know any functions that would be useful. They called this idea "Non-secret encryption".
          Then based on that model they discovered methods that were similar to RSA (Cocks, 1973) and Diffie-Hellman (Williamson, 1974).
          Apparently, even though they knew how to encrypt, they didn't realize that it could also be used as a digital signature scheme.

          The list of papers are:

          Basic theory:
          The possibility of secure non-secret digital encryption, J.H. Ellis 1970

          RSA:
          A note on "Non-secret encryption", C. C. Cocks 1973

          Diffie-Hellman:
          Non-secret encryption using a finite field, M. J. Williamson 1974
          Thoughts on cheaper non-secret encryption, M.J. Williamson 1976

          Historical:
          The history of non-secret encryption, J.H. Ellis 199?

          Those documents are in the gchq site, or somewhere near, but it is a PITA to search there (if you do, check both "non-secret" and "non secret", but I'd recommend google instead.
    • Re:Free information. (Score:3, Interesting)

      by raygundan (16760)
      Meh. That this device is "as fast as a modern PC" for the single task it was designed for is nothing particularly interesting. It is, as another reader pointed out, essentially just a large DSP. Just because a 400MHz GPU is many, many times faster than your 3GHz CPU at drawing pretty pictures, doesn't mean it's a better general purpose CPU. If you took all the millions of transistors in a P4 and made them all do NAND in parallel, you would have the world's fastest NAND gate, capable of doing a million n
  • Remarkably, the use of parallel processing (five tape channels) and short gate delay time (1.2 microseconds) allows the Colossus to match the speed of a modern PC

    Er, this is an obviously ridiculous statement. A modern PC is such an order of magnitude faster that it could probably run equations simulating the circuit behaviour itself and still run real time. Compare 1,000 values at 1MHz (which it probably isn't anywhere near in reality), and a slow tape data input (even with 5 of them), to 10 million trans

    • by DarkOx (621550) on Tuesday June 01, 2004 @08:45AM (#9302310) Journal
      Yes but you have to remember that it was built to do one specific thing. When you design something for a single use, you get to make all sorts of assumptions which will allow you to optimize very very much. My DVD recorder is probably hundreds of times slower then my Athlong 64 system yet no matter what software I use it records video smoother with fewer frame drops. On the PC something happens like it becomes neccecary to flush the disk buffer and it will drop a frame, its hardly perceptable but sometimes you can detect it. PCs are so universal that you get to make few if any assumptions and that means more processing time. I imagine if you tried to write software for this thing to say transcode mp3 files to odd or something riddiculus like that your PC would finish months before this machine does.
      • It doesn't say that it was cleverly designed to do a single purpose so that its as fast as modern processors. It says that its parallel tape drives were so fast that it can match modern processors. That is a ridiculous statement. Now, that doesn't mean that it isn't as fast as modern computers, but that it isn't because of the speed of the hardware.
    • Quite a few years ago there was an interview with one of the guys who worked on the Colossus. He stated that he had produced a machine code implementation of the task and ran it on the best PC he could find (may have been a PI or PII), expecting the PC code to run faster. He was surprised to find that Colossus was still much faster.
    • by MancDiceman (776332) on Tuesday June 01, 2004 @08:53AM (#9302346)
      Don't talk utter rubbish. You should be modded down for being a crank.

      This is custom hardware designed for the job. MHz and GHz don't come into it. If you don't believe me, consider why the processor on so many graphics cards is slower than the CPU in the machine, yet without it, the graphics would grind to a halt. A modern PC is a general tool - Colossus wasn't, and was specifically designed and built to break crypto as quickly as possible. Now, if you were to try and run Pong on it, fair enough, you'd find it incredibly slow... but that's not what it's there for. Colossus would however easily crack Enigma codes quicker than your over-clocked P4. And it probably doesn't have as many neon lights in it.

      Funny thing about slashdot - people seem to think they know all about hardware because they know the difference between a MHz and a GHz.
    • Yes, but the Colossus doesn't run XP
    • Add to that, the writers "modern PC" is a modern in 1996. Which was what? a 486?

      So while he may have been correct at the time the various parts of the project was underway, it's not true now.

  • The article mentions ENIAC, but not the Atanasoff-Berry Computer [iastate.edu] which pre-dated it, and which ENIAC was largely based upon.

    For more information, read "Atanasoff: Forgotten Father of the Computer [amazon.com]".

  • by fantomas (94850) on Tuesday June 01, 2004 @08:44AM (#9302304)
    The work has been done at Bletchley Park [bletchleypark.org.uk] by volunteers. Normally the Colossus machine is being rebuilt there and you can watch the guys working on it and ask them questions. I was at Bletchley Park (home of Station X, the UK codebreaking centre in World War 2) yesterday, brilliant, well worth a visit. It's run as a trust, by volunteers. They need your support. Bletchley Park receives no public funding. To date, the Trust has raised over 1 million in its fight for survival. A further 4.5 million is needed now to fund essential staffing, building refurbishment, infrastructure, planning and marketing costs. They are just about to lose 20 acres of the site to a private developer building a housing estate, and half the original Huts are falling down. The hut Alan Turing worked in has some of its windows covered with chipboard because the windows are broken and they don't seem to have the money to replace them. The paint is peeling and the wood is rotting, the wall round it has fallen over in parts.

    The code breakers in these small prefabricated huts probably shortened the war by two years and saved hundreds of thousands of lives. Surely us geeks can help save this site and remember their contribution? If you can't get there to volunteer, maybe use their online form and give them a small donation? Their website is going to be slashdotted at this rate, so how about slashdotting their intray with donations?

    • FWIW, the film ENIGMA [imdb.com] is a romanticized but entertaining thriller about another important, earlier (than Colossus), Bletchley Park decryption mechanism.
      • ...but if you get to Bletchley Park, for goodness sake don't mention the film U-571 [imdb.com] :-) the retired UK military people who are the tour guides get a bit twitchy that Hollywood makes out it was the US Navy and not the Royal Navy (UK) who grabbed vital code books from a sinking U-boat (which I think was actually U-110). (actually they are quite relaxed and happy to correct/ give more info , plus the U571 film makers donated a couple of huge u-boat props which are in the grounds of BP).
        • It was U110, captured by the crew of HMS Bulldog, complete with an Enigma machine and up-to-date codebooks (May 9, 1941). U559 and U506 were later captured with Enigma machines, the former by crew of HMS Petard (30 October, 1942), the latter by US Navy Task Force 22.3 (June 4, 1944)
    • by pjacobi (526409) <peter_jacobi@gmx.net> on Tuesday June 01, 2004 @10:41AM (#9303097)
      Often forgotten (outside Poland):

      The work on breaking Enigma started at the Polish Cipher Bureau with three Polish mathematicans Marian Rejewski, Henryk Zygalski and Jerzy Rozycki developing a mathematical model of its operation.

      At Bletchley Park, there is plaque commemorating this contribution.

      And the knowledge used was obtained by French intelligence, but only the Poles thought it possible to gain something out of it.

      Googling for Poland Enigma will give you a lot of sources.

      Or start here:
      http://www.paiz.gov.pl/oldpai/newsletter/an gielski /NR20.htm#Conquerors%20of%20Enigma
      http://www.awm .gov.au/news/codes.htm
      http://wings.buffalo.edu/i nfo-poland/web/history/W WII/enigma/U-571.shtml
  • by salmacis2 (643788) on Tuesday June 01, 2004 @08:46AM (#9302314)
    Colossus, and indeed the rest of the Bletchley Park operation was a tremendous example of war-time ingenuity.

    I would urge all UK-based \.ers to go and visit Bletchley Park as soon as possible. It's an amazing day out. It's just sad that the UK government doesn't appear to recognise the historical significance of BP and spend whatever is required to restore the site. Hut 6 and Hut 1, where most of the decoding was done are practically falling down these days.

    • by pklong (323451) on Tuesday June 01, 2004 @08:56AM (#9302361) Homepage Journal
      Oh great, a load of Slashdotters turning up. I can just imagine the poor guides when they ask the obligatory "Does anyone have any questions?".

      Also they had better rope off the area properly or for some reason the machine will print out "Visit my 1337 site goatse" or "First Post" constantly.
    • I would urge all UK-based \.ers to go and visit Bletchley Park as soon as possible. It's an amazing day out. It's just sad that the UK government doesn't appear to recognise the historical significance of BP and spend whatever is required to restore the site. Hut 6 and Hut 1, where most of the decoding was done are practically falling down these days.

      One of the few industrial donors to Bletchley Park has been - ummm - Siemens - who made Lorenz.

      So German industry understands the importance of Bletchley

  • by Anonymous Coward on Tuesday June 01, 2004 @08:49AM (#9302327)
    This is the real one! [wikipedia.org]. Ignore the other ones, this is the REAL wikipedia link. Verify it for yourself!
  • Make him faster, stronger.....
  • by Geiger581 (471105) on Tuesday June 01, 2004 @09:09AM (#9302410)
    The Colossi were not programmable (they just did precisely one thing rather well), so it may be hard to consider them computers in all possible senses. Konrad Zuse's Z3 (Wikipedia Link [wikipedia.org]) was also completed two years prior and was Turing complete, so it's hard to really give Colossus any credit other than the impact it had on the war.
    • Colossus wasn't the first computer, but I think it was the first all electronic computer, whereas the Z3 used physical relay switches.

      If you're after the first programmable computer then Charles Babbage's Difference Engine beat the Z3 by over 100 years (although he never actually finished building it the science museum reproduced it and it worked)
    • Two things - the Colossi were definitely programmable. I haven't got the reference handy, but there is an account of it in "Codebreakers: the Inside Story of Bletchly Park", where in the period between the end of the war and the decommisioning of BP some of the staff had fun programming the Colossi to do other computation tasks (such as print out the ten times table IIRC).

      Secondly, nobody realised (or, rather, proved) that the Z3 were Turing complete until 1998. Zuse had suspected it, but wasn't sure.
  • by Anonymous Coward on Tuesday June 01, 2004 @09:18AM (#9302453)
    One of my grad school professors wrote a detailed book on colossus as a project to keep him busy in retirement.

    "From Fish to Colossus: How the German Lorenz Cipher was Broken at Bletchley Park"

    by Harvey Cragon

    On amazon:

    http://www.amazon.com/exec/obidos/tg/detail/-/09 74 304506/qid=1086095280/sr=1-1/ref=sr_1_1/104-610257 7-9835954?v=glance&s=books

    I proofread an early copy of the book and it was quite interesting how the cryptanalysis was done and even more impressive what these people accomplished with technology that was, to quote Spock, not much removed from bearskins and stone knives.

  • by jdtanner (741053) on Tuesday June 01, 2004 @09:26AM (#9302509) Homepage
  • by Luigi30 (656867) on Tuesday June 01, 2004 @09:47AM (#9302641)
    Fatal error on tape0 - unknown error, paper exploded?
  • " Three months were spent re-drawing the machine using CAD (Computer Aided Design) software on a computer with a 486 processor."

    They could have saved 2 months by using a more recent machine.. ANYTHING...
  • by exp(pi*sqrt(163)) (613870) on Tuesday June 01, 2004 @11:20AM (#9303598) Journal
    I think the story goes something like this: a few years ago the team reproducing the Colossus set out by writing an emulator for the PC. It wasn't written that smartly and ran slower than the real thing. Now, several years later, that statement is being repeated more often than it should be. But I think that in the weak sense I have outlined it was once true.
  • Related stuff (Score:2, Interesting)

    by jarek (2469)
    Some of the stuff in the links below will be found in the Code Book. It's interesting stuff anyway.

    link1 [zen.co.uk]

    link2 [zen.co.uk]

    Happy reading.

    /jarek

  • Colossus has been Rebuilt

    Great! In time for the next X-Men movie too :-)
  • As others have mentioned, it's worth a visit. But go on a weekend, when the volunteers show up. I went on a weekday, and the tour guide was more into English country architecture than cryptography.
  • by Animats (122034) on Tuesday June 01, 2004 @01:02PM (#9304834) Homepage
    There were a number of devices in that era, Colossus included, that really weren't computers.
    • Harvard Mark 1 [maxmon.com] (1939 - 1944) - semi-programmable electromechanical computing machine.
    • Zuse Z3 [tu-berlin.de] (1938-1941) - small general purpose relay computer. Good architecture, but limited by relay speeds to a 5Hz (yes, Hz) clock. First floating point unit. No jump instruction, due to a low budget. The later Z4 (1945-1949) had jumps and conditional branches.
    • Atanasoff-Berry [iastate.edu] (1937-1942) Programmable, electronic arithmetic, binary, but memory was a rotating drum of capacitors.
    • Colossus (1944?) Special-purpose key-testing machine.
    • ENIAC [upenn.edu] (1943-1946) - plugboard-programmed tube machine. No general purpose memory, just registers. Tube ALU.
    • IBM 603 Electronic Multiplier [ibm.com] (1946) - first commercial electronic computing product. Punched card I/O, not truly programmable, but electronic multiplication and division.

    Most of these machines had electronic arithmetic units. The big problem was memory. There were no good memory technologies yet, and none of those machines had much memory. They all basically had a few registers, like a calculator. Each bit of memory required a relay, a tube, or a discrite capacitor and switchgear.

    Finally, the memory problem was solved. EDVAC [upenn.edu], (1947-1952), had 1K of mercury-tank delay line memory. This was a lousy main memory technology (you had to wait for the word you wanted to come around, like a disk), but allowed reasonable memory sizes. It was clunky, but at last, there was memory.

    With the memory problem partially solved, various groups started building machines. Pilot ACE, ACE, and IAS date from this period.

    The UNIVAC I (1948-1951) had it all - memory (1K words, in mercury tanks), console, tape drives, console typewriter, programmability, electronic arithmetic, a reasonable instruction set, and self-checking. It was built, sold, and used. UNIVAC I was the first of these machines that a modern programmer would consider usable.

    • CSIRAC [wikipedia.org] - (1949 - 1961) - digital computer, entire machine housed at melbourne museum [vic.gov.au] (victoria, australia) after service with CSIRO ( formerly called CSIR), Radio physics lab Sydney University finally residing at Melbourne University [mu.oz.au].

      Interesting facts [mu.oz.au] ...

      • approx 5th digital computer created


      • one of last original computers intact
        CSIR Mk1 or CSIRAC designed by team lead by Maston Beard and Trevor Pearcey for CSIR (CSIRO [csiro.au])
        primary store of 768 20-bit words
        magnetic drum 4,096 word capacity
        10ms access time
        clock

What ever you want is going to cost a little more than it is worth. -- The Second Law Of Thermodynamics

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