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Security Science

New Technique Could Trace Documents By Printer 287

An anonymous reader submits "From this article at Purdue News, 'Researchers at Purdue University have developed a method that will enable authorities to trace documents to specific printers, a technique law-enforcement agencies could use to investigate counterfeiting, forgeries and homeland security matters.' The neat thing is that they are exploiting the characteristics of the print process itself to identify the printer." <update> One of the folks e-mailed me to say that the HP LaserJet 9000dn was one of the big ones tested with.
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New Technique Could Trace Documents By Printer

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  • by FortKnox ( 169099 ) on Thursday October 14, 2004 @01:30PM (#10527089) Homepage Journal
    Sure, it sounds nice for the gov't to track down bad guys, but what if the technology to do this becomes public? Most of the /. population won't be able to pass notes to girls without them finding out who its from!!!
    • by Nom du Keyboard ( 633989 ) on Thursday October 14, 2004 @02:42PM (#10527840)
      Most of the /. population won't be able to pass notes to girls without them finding out who its from!!!

      Boy are you out of date. SMS, the only way to message in class.

  • Obviously (Score:5, Funny)

    by Donoho ( 788900 ) on Thursday October 14, 2004 @01:31PM (#10527099) Homepage
    They got the memo about cover letters on their TPS Reports.
  • Sorry but... (Score:5, Insightful)

    by mfh ( 56 ) on Thursday October 14, 2004 @01:32PM (#10527116) Homepage Journal
    The technique uses two methods to trace a document: first, by analyzing a document to identify characteristics that are unique for each printer, and second by designing printers to purposely embed individualized characteristics in documents.

    Sorry to rain on your parade, Homeland Security, but if counterfeiters can counterfeit hard currency worth a damn, they can certainly hack a printer to make it quickly change configurations at the drop of a hat. Get your marker and bic pens ready, all ye counterfeiters!
    • Re:Sorry but... (Score:5, Insightful)

      by ZZeta ( 743322 ) on Thursday October 14, 2004 @01:43PM (#10527238)

      In fact, a lot of effort seems to be put in stopping our regular Joe from counterfeiting hard currency. They have taken action against small time counterfeiters through this method or the hexagon (or was it a pentagon) that's printed in every 20 Dollars bill.

      But the really big counterfitter, the one that's printing millions of dollars every month doesn't use HP's Laserjet. Come on guys, do you really think they're printing currency in a small time printer?

      Government should be after big-time counterfiters, those settled in Colombia or North Korea. Those guys actually influence US economy.
      Not John Doe who amuzes himself printing 5 bucks in his HP printer to brag with his friends.

      • Re:Sorry but... (Score:5, Interesting)

        by NoMoreNicksLeft ( 516230 ) <john.oyler@noSpAm.comcast.net> on Thursday October 14, 2004 @02:08PM (#10527367) Journal
        Currency is printed by the fed, the biggest crook of all. And while the counterfeiters in Colombia and N. Korea do take a cut of the ill-gotten gains this way, and without permission at that, the crooks in charge trust them to not ruin it so completely that there is no wealth left to steal.

        However, the fed can't have that same trust of joe sixpack, because he is an amateur crook, and might teach his buddies how to do the same. He is the biggest threat, and not to the economy... but rather to the scam itself.

        If you bother writing your congressmen, add an extra sentence or two insisting that the government resume its right to coin money, and take it out of the hands of a private corporation owned by foreigners.
      • Not effective (Score:2, Insightful)

        by e_AltF4 ( 247712 )
        Low end laser and ink printers are so cheap currenrly - you can pay for two new ones with the first sheet of paper you fill with forged $ bills.

        Smash the el-cheapo printer, dump the parts, get a new one, start over. Probably not very effective to stop counterfeiting currency.
      • Re:Sorry but... (Score:3, Interesting)

        by thedillybar ( 677116 )
        >Government should be after big-time counterfiters, those settled in Colombia or North Korea.

        I think they're taking the same approach to counterfeiting as Microsoft does to pirating. Microsoft stops Joe Schmoe from pirating by only allowing x number of installations per key. They still have XP Corporate edition which has no limit.

        They know they're not going to stop the big-time guys, so they don't try. If you want to bad enough, there's nothing they can do to stop you (or even make it not worth yo

      • But the really big counterfitter, the one that's printing millions of dollars every month doesn't use HP's Laserjet. Come on guys, do you really think they're printing currency in a small time printer?

        The 9000 is the largest printer HP makes. It is very, very fast. Probably not as fast as some of the Xerox docucenters and such, but fast.

        The problem is that people are stupid and don't actually examine cash they take. It used to be that cashiers could tell instantly if you handed them a fake bill, on f

      • Re:Sorry but... (Score:3, Insightful)

        by Qrlx ( 258924 )
        Government should be after big-time counterfiters, those settled in Colombia or North Korea.

        Is it even a crime to make counterfeit U.S. currency if you're not in the U.S.? What would you have the Secret Service do, send in Delta Force and/or Arnold Schwartzenegger to liquidate the operation?

        Taken on the whole, I'm sure the devaulation of U.S. currency due to counterfeit is more than offset by the fact that if you want to buy oil, you have to spend U.S. dollars, which keeps demand artifically high. (See
    • The technique uses two methods to trace a document: first, by analyzing a document to identify characteristics that are unique for each printer, and second by designing printers to purposely embed individualized characteristics in documents.

      Sorry to rain on your parade, Homeland Security, but if counterfeiters can counterfeit hard currency worth a damn, they can certainly hack a printer to make it quickly change configurations at the drop of a hat. Get your marker and bic pens ready, all ye counterfeite

      • The arsenal is big enough. It's time for them to actually do their jobs and stop whining about needing more tools. How about if everyone had to register with the police staion nearest their place of employment? Is that just another tool in the fight against child abuse? How about we tattoo everyone on the forehead with a bar code so the pulic-place cameras can track everyone? Would that be just another tool for Homeland Security too?

        The Constitution guarantees my right to be secure in my effects and p
        • Sorry but that tinfoil-hat additude doesn't make sense. It's just another tool, like handwriting analasys. Would you hand-write any documents that you don't want traced back to you when you know full well that the government can track your handwriting? Of course not. So now you know they can track the printer inkwriting too. Jeez, if you're that paranoid, don't use it.

          You know the government can compare fingerprints. The government can compare DNA. The government can match paper fiber samples and p

    • Re:Sorry but... (Score:3, Insightful)

      Do you really think this is aimed at counterfeiters? They have been changing the bills every few years and the new ones get hard to fake. The paper, and the pressed feel of the ink are all difficult to fake on printed stock.

      Nope. This is probably a quiet attempt to track printers and copiers for death threats and documents for non-counterfeiting criminals and terrorists.
  • by bizpile ( 758055 ) * on Thursday October 14, 2004 @01:32PM (#10527117) Homepage
    The neat thing is that they are exploiting the characteristics of the print process itself to identify the printer.

    From the article:
    The technique uses two methods to trace a document: first, by analyzing a document to identify characteristics that are unique for each printer, and second by designing printers to purposely embed individualized characteristics in documents.

    So there are actually two ways and the second requires redesigning printers. I wonder if the government will push printer makers in to changing their printer in the "interest of national security."
    • I can see an emerging market in "stealth printers"(tm) if that happens. This is likely to go the way of the P4 serial number. -- nothing interesting here
      • I can see an emerging market in "stealth printers"(tm) if that happens. This is likely to go the way of the P4 serial number. -- nothing interesting here

        Or counterfeiters will just keep using the printers out there today and find some way to alter the printing process. This will only stop the causal counterfeiter that is probably stupid enough to get caught without this technology.
    • Crap, yet another DRM-less/security-less gizmo I gotta hoard for when they're all wired into Ashcroft's penal colony.

    • Certainly, banding effects like they show in the article might be something that is relatively unique. Most printers have a way to align the printheads to eliminate that, I wonder if they tried matching in the face of print head realignment.

  • by Bruha ( 412869 ) on Thursday October 14, 2004 @01:32PM (#10527120) Homepage Journal
    The problem here is many of the peices they would use to track the printers are integral parts of the replacable toner cartridges and printer ink kits. Only printers that have perm drums and heads will be easily traceable.
    • Just hide a id number in the "random" point dithering used in colour prints... It would come from the electronics, so no use changing toner/ink cartridge..
      • The use of a special pattern in bill designs is how they can prevent graphics tools from manipulating those images. Why couldn't that also be used in the printer itself or printer drivers? (Certainly there's be some buffering requirement so that entire pages could be examined prior to actually printing, but it's possible.)
    • so, now I expect that Lexmark will claim that third-party toner cartridges could get me in trouble with the law if they had been previously used for some nefarious purpose.
    • The problem here is many of the peices they would use to track the printers are integral parts of the replacable toner cartridges and printer ink kits. Offset each horizontal line by zero or one pixels, making the line number correspond to one bit in the binary representation of the printer's serial number:

      embedPrinterID(serialnumber) {
      offsets = binaryvalue(serialnumber);
      for i in len(offsets) {
      page.lineoffset[i] = offsets[i];
      }
      }

      If the FBI can read zero-wiped hard drives by measuring quantum charact

  • by FerretFrottage ( 714136 ) on Thursday October 14, 2004 @01:33PM (#10527129)
    ....I use to use one of those automatic birds that would carve the letters into the stone tablets, but the cost of replacement beaks was very high (and BTW, only use OEM beaks, 3rd party beaks void your bird warranty)

  • Great! (Score:5, Funny)

    by User 956 ( 568564 ) on Thursday October 14, 2004 @01:34PM (#10527135) Homepage
    Then maybe they can finally track those unverifiable CBS documents back to Karl Rove.
    • In Soviet Russia... (Score:3, Interesting)

      by GQuon ( 643387 )
      In Soviet Russia, they actually did this in a low tech way:

      A little-known feature of the U.S.S.R. under Communism was that when someone purchased a typewriter, it was delivered to the local police office. The people there took a razor blade and nicked various characters, then registered the owner, the serial number of the typewriter, and a complete sample of the typewritten output. Since the characters exhibited consistent errors, if a samizdat appeared, all that was necessary would be to compare the cha

  • by jea6 ( 117959 ) on Thursday October 14, 2004 @01:34PM (#10527143)
    From an Interpol paper from a few years ago...

    "DOCUMENTS PRODUCED BY BUSINESS MACHINES

    It goes without saying that the proliferating market of modern business technology
    such as copiers, fax machines and printers reduces a systematic forensic approach.
    However, a number of projects report progress in the following:
    • Image retrieval from used thermal transfer printer rolls
    • Defining substrate attributes for photo quality ink-jet imaging
    • Detection of laser printer defects for printer identification
    • Evidential value from ink-jet printers and inks
    • Identifying photocopying toners using FTIR, DRIFTS and Pyrolysis-GCMS
    • Classification of ink-jet printers and ink
    • Classification of and identification of Laser printers
    • Electronic database of computer printer data
    • Examination of faxed documents
    • Classification and identification of fax fonts
      Classification of full colour copiers
    • Counterfeit Protection System codes of laser copiers
    • Dot patterns of colour ink-jet printers

    Doherty (31) gives an overview on state-of-the-art classification of ink-jet printers
    and inks. Interestingly, the findings indicate that the results of TLC analysis
    "before" and "after" show significant differences because the ink-components are
    modified by heat during the print process. For specialists in traditional typewriting
    examination, the overview of Frensel (41) on typewriters produced in the former
    East Germany is of interest when identifying products manufactured before and
    after World War II. Gervais & Lindblom (43) present a case illustrating detection of
    digital manipulation on a facsimile printout. Hammond (47) compares the collected
    technical data of facsimile machines. The demonstration of secondary typewriting
    and alterations by the use of grids is today easily carried out by using the
    appropriate computer software, as shown by Hicks (55). If there are actually
    different computer assisted typewriting data collections, the system DRUIDE,
    developed by Holzapfel & Marx (58) is comprehensive and designed for routine
    casework. The traditional typewriter - disappearing on the market - still has its
    forensic impact. Few references go back to the roots of typewriting examination and
    commercial production, e.g., in the former Eastern Block. Horton (60) compares the
    identifiability of the flatbed scanner and its products by comparing the marks on
    scanned images. Lauterbach (68) describes 30 fax machines and their characteristic
    printouts for identification purposes. A survey by Tweedy (129) on state-of-the-art
    colour Laser copier identification by bitmap coding includes an overview of
    counterfeit protection by the characteristics and class of the major copying
    machines on the market. Wagner (134) presents the "Australian Toner Library" and
    the discriminating power of FTIR as compared to ATR. In a similar direction, but
    looking more specifically at the dating and sourcing of the Transmitting Terminal
    Identifier on a fax document, is a study by Westwood & Novotny (138). White et al
    (139) show the benefits of Surface Enhanced Resonance RAMAN Scattering
    Spectroscopy (SERRS) for an almost non-destructive spectroscopic examination of
    inks. Winter (141) studied the evidential value of the dot pattern of colour ink-jet
    and bubble-jet printers for individual identification."

    http://www.interpol.int/Public/Forensic/IFSS/meeti ng13/Reviews/QDnoHw.pdf [interpol.int]
  • Reminiscing (Score:5, Funny)

    by gregarican ( 694358 ) on Thursday October 14, 2004 @01:34PM (#10527145) Homepage
    I recall a Brady Bunch episode where Alice was typing letters and sending them to Jan to make her feel special. She was feeling overlooked, being the middle daughter and all. Well the Bradys traced the letters back to Alice's typewriter because it dropped its Y's. Not sure what all of this means, but it seems ontopic.
    • Wait! There was a charles in charge episode where they did basically the same thing! One of the sisters was writing to a columnist who had charles doing the letters that week, and he found out because of the dropped g's!

      Wait! I need to go stab myself in the brain to get these memories out!
      • Just like the Brady Bunch episode where Greg steals the rival football team's mascot (Lucille the goat). This was almost exactly duplicated in a Differ'nt Strokes episode where Willis pulled the same prank. I don't think Todd Bridges capped or stabbed the mascot, however.
    • All the more weird given speculation that the actress who played Alice is gay.
    • Re:Reminiscing (Score:3, Interesting)

      by BenFranske ( 646563 )
      Actually, this is more on topic than you might think. Somewhere in my library I have a U.S. Secret Service (propaganda) book from the 1950s about how they track down those that threaten the president and counterfeiters. In more than one example case given in this book they used specific characteristics of typewriters to track down letter writers. This has been largely impossible since the advent of non-mechanical personal printing techniques. Although, I disagree in the strongest terms with digital watermar
  • Already in place. (Score:2, Interesting)

    by B5_geek ( 638928 )
    I work for a large copier/network printer company (Not Brand X), and our machines have been able to do this for a very long time. A VERY tiny bar-code style serial number is placed everywhere in any printed and copied document (you need a microscope to see it).

    This might be news because small desktop printers have never had small enough 'pixels' to keep it smaller then your eye can see.
    • Re:Already in place. (Score:5, Informative)

      by Anonymous Coward on Thursday October 14, 2004 @02:09PM (#10527377)
      Ok, you are so full of shit you stink from here.

      your printers are incapable of printing less than it's maximum dpi. and no laser or inkjet let alone a dye-sublimation printer is capable of microscopic printing.

      nice of you to make up crap, but let's at least make it slightly believeable.

      show me a proof before you start throwing about lies as truth. Espically when it goes against physics and mechanical capabilities.
      • A few years ago, there was a big fuss about color printers and copiers having some kind of identifying information of the printer encoded in the dithering patterns used for halftones.

        At that time, how to read this information wasn't generally available to the public.

        Probably this is the same stuff warmed up again.
        • There is only one situation for color printers to print an identification barcode, namely if someone tries to counterfeit money. Most color printers do this, usually in a very pale yellow which cannot be seen with bare eyes, but easily recognized using UV light.
      • by Greyfox ( 87712 ) on Thursday October 14, 2004 @03:16PM (#10528362) Homepage Journal
        I worked for a printing systems company a while back and I seem to recall management mentioning that the company cooperates with the government in terms of helping to track printers and foil counterfeiters. I don't believe it's a microscopic number, but every printer will print slightly differently due to flaws in the manufacturing processes for heads and toner cartrdiges and the materials they use. The upshot of all that is that if The Law suspected that a letter came from your printer, they CAN verify that, given the original letter and your printer. It'd be pretty easy to send type samples for every printer serial number off to some federal database somewhere, though I don't know that it's done currently.
    • I note a couple of replies have ripped this to shreds, but this concept is actually quite feasible.

      Instead of relying on the laser engine or inkjet head (with its limited DPI) to print the barcode, it would be fairly simple to have the printer essentially stamp it (impact style) onto each sheet as it passes through. Make the stamp sufficiently small, or perhaps use a special ultraviolet toner, and you now have a way to trace every sheet of paper that comes out.

      Come to think of it, the impact itself should
      • Just make the print feed rollers a bit tighter where they leave a tiny imprint that was machined onto the rollers. No need for additional parts or special ink, but it would take special equipment to detect the imprints. That would mean only those with deep pockets could do the tests to see if something was faked, which kind of negates it's usefulness to anyone but the Government. Joe Clerk couldnt tell if the documents were perfectly forged. US Currency uses a combination of microprinting, watermarks, threa
  • print heads in carts (Score:4, Interesting)

    by magarity ( 164372 ) on Thursday October 14, 2004 @01:36PM (#10527166)
    What about HP inkjet printers with the way they print from the cart? Toss it and do you have a "new" printer according to this kind of tracking?
  • If, however, the printer cartridge is changed after a document is printed, the document no longer can be traced to that printer.

    And if this should occur, they have to resort to printing identifying "watermarks" in documents, which isn't terribly different from existing currency technology/etc.

  • by multiplexo ( 27356 ) * on Thursday October 14, 2004 @01:37PM (#10527178) Journal
    Purchase printer with cash. Do not register printer. Dispose of printer after a certain number of counterfeiting runs. Counterfeit more money to purchase more printers, repeat as necessary.

    As far as those who are concerned about the government secretly tracking them down by the printer signatures in their anonymous manifestoes I think there are other things to worry about from the government.

    • Purchase printer with cash.

      Just don't use the counterfit cash from your last print run.

    • by Frank T. Lofaro Jr. ( 142215 ) on Thursday October 14, 2004 @03:21PM (#10528430) Homepage
      If you are going to encourage criminals, at least do it right. Here is what to suggest.

      Steal printer in dead of night while wearing masks. Register printer to people in rival crime syndicates. Use printer to weigh down the bodies you throw in the river. Use the counterfeit money to buy drugs, sell the drugs (at a nice profit, thanks to the DEA helping keep prices high by limiting supply to those who know how to be effective criminals) to get real money and use that money to buy new masks and paper for the printer. Sure you could steal those too, but that is beneath you if you call yourself a professional criminal. :)
  • make a virus/worm/spyware buddy that secretly emails a copy of everything that goes through your spool directory to bigevilspies@usa.gov

  • to those who appreciate freedom.
  • by Anonymous Coward on Thursday October 14, 2004 @01:41PM (#10527219)
    About 15 years ago, I had an attorney do some work for me and he boasted about a software package he used that made small custom mutations to the font each document was printed in, such that once such a document was printed, it was very difficult for anyone to add or replace pages without being detectable as a later change to the original document.
    • made small custom mutations to the font each document was printed...very difficult for anyone to add or replace pages without being detectable as a later change to the original document.

      Just have your own, custom True Type font -- and remember not to embed it in any of your documents. Sounds like security through obscurity however, since it works best when you don't suspect it's being used.

      Of course, if they redo the entire document with their revisions, the font will fully match and you're left arguin

  • by ralphus ( 577885 ) on Thursday October 14, 2004 @01:41PM (#10527223)
    When I'd batch up my print jobs for 6 months, print them all out the immediately, destroy my printer and get a new one. :)
  • Xerox Watermark (Score:5, Interesting)

    by DigitalRaptor ( 815681 ) on Thursday October 14, 2004 @01:42PM (#10527229)
    Xerox (and others, I'm sure) have done this for quite some time.

    About 5 or 6 years ago a friend that owned a print shop and used a Xerox color laser printer told me about Xerox imprinting every print with a watermark that could be decoded to obtain the serial number of the actual machine used in the printing.

    The watermark was undetectable to the human eye and didn't alter the presentation of the image.

    They did this at the behest of the government because it's so easy to print money on these things. This way they can track the money back to the machine via the serial number.
  • CSI??? (Score:2, Funny)

    by Fouquet ( 753286 )
    Oh come on. They could do this on CSI a couple of years ago. What's taken 'real' law enforcement so long????
  • "Printer fingerprinting"

    Just another term to add to your IT vocabulary.

  • by Shadowlore ( 10860 ) on Thursday October 14, 2004 @01:44PM (#10527251) Journal
    So basically, they are saying if they had the original printer, and the document they could put the two together.

    In order for this to provide the means to track a forged document to it's source will require printers to be "tested" when sold so their "printing fingerprint" can be recorded.

    Otherwise, at best if can serve as a confirmation, not a tracing method. This is how ballistic characteristics test are used. They are used to confirm that a gun fired a bullet, not to trace the bullet to the gun.
    • I'm not convinced from the paper that these techniques are exact enough to narrow it down to a specific printer. Realigning the print heads or changing cartridges would change the printing effect and make it harder to trace. Kind of like running a file down a gun barrel.

      It seems it would be technically possible to add taggants to trace ink and toner like they do for some explosives and fertilizer. Still, given the retail nature of ink/toner cartridges it would be difficult to narrow it down past a particul
  • Wow! A plan to have traceable embedded signatures in all printers and resulting documents. Finally, a proposal for a government mandated way to trace all documents back to their creator. Remember it is for homeland security, so don't dare oppose this on the idea that it would chill free speech and decent. Besides, think of the children....Boy I feel safer already.

    Really, I have to say this is a bad idea. The article goes beyond a forensic technique of trying to match documents to the printer that made it.
    • The excuse for this new proposal is that it is for homeland security and preventing counterfeiting. But the broader truth of the matter is that this would be another nail in the coffin for free speech.

      *Puzzled look* Huh? When did they confiscate all the pens and pencils?
      • Yes, you can use pens and pencils, but if you want to reproduce those documents on a copier that has an embedded sig then you still have the same problem.

        Keep in mind that it was the printing press, with its ability to cheaply mass produce content that helped spread the kind of dissent that led to the American Revolution. These days, Thomas Paine, who printed patriotic tracts like Common Sense, might be tracked down as a possible terrorist.

        The ability to truly speak freely is fading, if it ever existed. T
    • This would mean that every document printed would have a traceable signature; the protest letter you sent to congress, the art project you made with your kids, the protest flyer you posted on campus--everything.

      If your speach requires you to be untraceable, then by and large you've already lost.

    • *Yes, I know this is an over simplification.

      No....no, it isn't.

  • I read the better-than-a-notch-in-the-e dept. and thought, "Hm, Microsoft's logo has a notch in one o."
  • Nothing new... (Score:2, Insightful)

    by jhdevos ( 56359 )
    This reminds me of older detective novels, where letters typed on typewriters are often important clues. The forensics lab looks at the blackmail note, and knows the exact brand and type of the typewriter it was written on - after which the killer, being the only one in a hundred miles with that specific typewriter, is easily found :)

    Jan
  • For sensitive documents you do not want traced to you:

    Print the original on your home / work printer. Take it to a copy shop to make a second generation. Take it to another copy shop to make a third generation copy. Repeat until your personal level of paranoia is satisfied. Copy the finals semi-anonymously at a high volume, self service location in a large city. Check for security cameras first.

  • by jmcmunn ( 307798 ) on Thursday October 14, 2004 @02:14PM (#10527438)
    A lot of what makes the difference in each printer such that they can tell the printer that was used will be based on mechanical variances between printers. And I would have to guess that if I drop my printer from a height of about 6 ft, there will be enough mechanical difference in the way it printed before I dropped it that their test (at least the mechanical part) will be unable to detect that it was my printer.

    For that matter, I would have to think that switching ink cartridges (or drums), switching gears between printers, switching paper trays, possibly even print drivers will have a large enough effect that this method will not be able to correctly identify nearly as many printers correctly as they claim given the fact that conterfeiters will be trying to beat them at their own game.

    Just my thoughts...
  • back documents printed to virtual printers (like that of Adobe Distiller) !?!
  • by funkdid ( 780888 ) on Thursday October 14, 2004 @02:16PM (#10527472)
    Law enforcement has been able to do this since at least 1994. Anyone ever watch any of the crime shows, or perhaps know someone who does forensic IT stuff, or perhaps is familiar with how printers work.

    There's another *New* technique that Law Enforcement will be using, it allows them to view data on your hard drive that has been erased!!!!

  • Never find out about Kinko's.
    • I worked at Kinko's for years. At least their color photocopiers had traceable features for as long as I worked there. Of course we all know if you try to copy cash on a color copier, it'll spit out entire sheets of green that cannot be turned off by the user. A tech has to come reset it and by policy, law enforcement is notified. But if you look super super closely, there is a pattern (not random, but specific to a particular copier) of yellow that can be used to track a copy back to a machine (and in
  • Homeland (Score:5, Insightful)

    by Halo- ( 175936 ) on Thursday October 14, 2004 @02:23PM (#10527589)
    Ah yes.... "Homeland Security". I'm so sick of this word, it's like "paradigm shift" except polictically loaded. The "for the children" of our generation. Why is it no one can discuss anything vaguely security related without linking it to "Homeland Security"? It's practically to the point that your Happy Meal(tm) come with free Homeland Security(tm) inside!

    Does anyone beleive that if these devices make it to market, the "evil doers" are going to rush right out to the store and buy a printer with a "Homeland Security Inside" sticker on it? And then properly register it? Anyone with serious criminal intent is either going to use a non-equiped printer, or a printer which is stolen or misleadingly registered.

    Don't get me wrong, this is kinda cool, and I'm sure it will help for things like kidnappings, but "Homeland Security"? Give me a break.

  • Long Live the PHOTOCOPIER!

    ILL Clinton Machinima Movie Maker [illclan.com]

  • by gd23ka ( 324741 )
    "We will actually modify the way the printer puts marks on the paper," Chiu said. "This method is very difficult to get around because information about the internal workings of specific printers is not commonly available, even on the Internet." How long before this changes and people start soldering modchips into their printer circuitboards?
  • If, however, the printer cartridge is changed after a document is printed, the document no longer can be traced to that printer.

    So we'll be able to catch the dumb terrorists now.

  • The Purdue researchers are overcoming that problem with software that causes a printer to embed its own unique "extrinsic signature" in a printed document, regardless of which printer cartridge is in a machine..."We will actually modify the way the printer puts marks on the paper,"

    W00t, my fortune is made. I ought to be able to sell my pre-embedded ID LaserJet on eBay for what it cost me now to the paranoid of the world. Bids start tomorrow at $900!

  • So who will be first to decode the eprom and send that presidential death threat using the ex-boyfriend's printer code?

  • Banding can be altered from one printer to another by adjusting the laser intensity, how long each laser pulse lasts and the precise positioning of a small motor that steers the laser beam inside the printer.

    There go my high-quality Photoshop prints. And just when color lasers were getting good enough and cheap enough to consider.

  • Fax it (Score:2, Interesting)

    by HexaByte ( 817350 )
    Print it, fax it, copy it and then let them try to find the orginal printer.

    If I'm really THAT into keeping my identity secret, I'll just print it out at some kiosk in a mall.
  • I'm making all my important documents by cutting out letters from the newspaper.
  • by gellenburg ( 61212 ) <george@ellenburg.org> on Thursday October 14, 2004 @03:37PM (#10528623) Homepage Journal
    Jefferson is rolling over in his grave.
  • The old USSR days (Score:5, Interesting)

    by hotspotbloc ( 767418 ) on Thursday October 14, 2004 @04:07PM (#10528948) Homepage Journal
    Back in high school in the '70s I had this hard core right wing, two terms in Vietnam, history teacher. He hated the USSR and everything it stood for.

    He told us this story (BTW, I have no idea if it is true.) about how all photocopiers in the USSR had a serial number etched on the glass so the copies it made could be traced. Much easier to track down papers proclaiming the joys of Liberty I guess.

    Well, that teacher has past on but I really wonder what he'd think of all this? All kidding aside is the US starting to look a little like the old USSR?

Every nonzero finite dimensional inner product space has an orthonormal basis. It makes sense, when you don't think about it.

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