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Colossus has been Rebuilt

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."

18 of 279 comments (clear)

  1. Clever use of what you have... by jarich · · Score: 2, Insightful

    Just goes to show what can be done when you are clever about using what you have.

    1. Re:Clever use of what you have... by Analogy+Man · · Score: 2, Insightful
      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 spend more than half of our waking hours on occupations no more inspiring.

      --
      When the people fear their government, there is tyranny; when the government fears the people, there is liberty.
    2. Re:Clever use of what you have... by Lodragandraoidh · · Score: 4, Insightful

      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.

      --

      Lodragan Draoidh
      The more you explain it, the more I don't understand it. - Mark Twain
  2. A tragedy by sql*kitten · · Score: 5, Insightful
    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.
    1. Re:A tragedy by eggoeater · · Score: 5, Insightful

      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...

  3. Free information. by chuck54 · · Score: 2, Insightful

    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.

  4. Not really by Anonymous Coward · · Score: 0, Insightful

    I really put that down to two things:

    1) Most people in England still only have 486 computers
    2) He's talking about deciphering stuff off a paper tape, something a modern PC can't do at any speed
    3) An old guy bragging about life's accomplishments (which is okay).

    Don't get me wrong, this is a brilliant technical advance for the 1940's, but not even close to modern computer. This is really pandering to a British audience ("Look mates, at once time, we were the leaders in computer technology!")

    1. Re:Not really by Anonymous Coward · · Score: 2, Insightful

      Most people in England do not have computers based on 486s - I'd be surprised if it was more than 10%. I would suggest that low end P4s are in the majority

      He never said they did. He just said that this would be an explanation of the performance claimed.

      Any PC with a serial port can read a paper tape with a suitable paper tape reader attached (I've done this in the recent past)

      I think he was joking, and using this to explain why a modern PC would be slower than a 60 year old valve based machine.

      Better than a kid whinging on about things that he doesn't understand.

      He wasn't. You were. It was a joke post to explain something that is apparently not the case. Don't take it so seriously.

  5. A modern PC could emulate it in physics! by pslam · · Score: 2, Insightful
    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 transistors at 3GHz.

    Funny thing is so many people seem to think there's nothing odd about it.

    1. Re:A modern PC could emulate it in physics! by DarkOx · · Score: 3, Insightful

      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.

      --
      Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
    2. Re:A modern PC could emulate it in physics! by MancDiceman · · Score: 5, Insightful

      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.

  6. Support Bletchley Park by fantomas · · Score: 5, Insightful
    The work has been done at Bletchley Park 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?

  7. Wait! Wait! there's a pattern here by nounderscores · · Score: 1, Insightful

    Britain invents, loses interest, somebody else commercialises, and then Britain still wins the war.

    How do those Brits do it?

  8. Thats not what the article says. by Bill,+Shooter+of+Bul · · Score: 2, Insightful

    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.

    --
    Well.. maybe. Or Maybe not. But Definitely not sort of.
  9. Speed of a modern PC by exp(pi*sqrt(163)) · · Score: 2, Insightful

    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.

    --
    Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
  10. Re:Reminder: by gowen · · Score: 2, Insightful
    In a paragraph about the Altair 8800 you'd think perhaps the context of "For the Altair 8800" wouldn't need to be put into every sentence so some clueless /.er wouldn't try to take it out of context.
    No, you'd simply write "working on the Altair 8800 Bill and Bob made its first programming language".
    It's called clear, concise writing.
    --
    Athletic Scholarships to universities make as much sense as academic scholarships to sports teams.
  11. Re:Integrated CPU instructions by Short+Circuit · · Score: 3, Insightful

    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 about 44Mb per frame. At 24 fps, that's about one gigabit per second. That's an awful low refresh rate. Let's raise it to 56Hz. Now we're at 2.33Gb/s, more than normal PCI. Let's go for a smooth 85Hz: Now we're at 3.54Gb/s. Let's look forwards to higher resolutions, say, 3200x2400@85Hz: 14.17Gb/s. More than the latest HyperTransport revision can handle. By this time, you've already crowded out hard drive and network access. Your sound might be in trouble too.

    That's an awful lot of bandwidth. And don't forget the space on the CPU die, and cache pollution for other processes. And Memory latency, not to mention the fact that a lot of that memory could be used for other game data.

    That's not to say there wouldn't be advantages. You could also conceivably perform physics calculations like collision detection and simple FEA.

    All in all, though, it's more efficient to have a multiprocessor setup where specific tasks are run on specialized hardware.

  12. Re:The ARM bombshell by Panaflex · · Score: 2, Insightful

    Ever used a Zaurus or a iPaq( That's why it's called StrongARM )? How about a newer Palm Pilot?

    The ARM processor is a wonder of low power design!

    Perhaps I will crawl back into the cave and stare at the shadows...

    Pan

    --
    I said no... but I missed and it came out yes.