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New Technique Could Trace Documents By Printer
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.
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!
The dangers of knowledge trigger emotional distress in human beings.
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."
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.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
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
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...
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.
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?
Like woodworking? Build your own picture frames.
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 papers and as far as I'm concerned that means I have a right to dispose of my papers in any way I see fit. That includes anonymously if I so choose. Giving anybody, especially the government, the ability to track those papers back to me is just not right. Are we having fun yet watching the Constitution get raped repeatedly these last few years? Once they're done with it you-know-who will be asked to bend over next.
Um what?!
Just because you printed a document doesn't mean you wrote it.
If you post an article (which you don't want authorities knowing you wrote) to a distributed network, then people can print it on printers from all over the world.
Not to mention they don't seem to have included the technology in my Daisy Wheel printer...which is fine for text and simple ascii text...
-={ Security does not exist - give up }=-
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.
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 arguing over the validity of the font used.
Oh, CBS is doing that already!
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Key words there: as long as.
Example: The DMCA and PATRIOT act authorized the use of some pretty brutal tactics, technologies for which were also developed without foresight of this possibility.
How do we know there won't be a PATRIOT 2 act, just as gullibly let through the Legislative branch of our government that will authorize, say, tracking down all 'suspicious with reasonable doubt' messages using this. Your private e-mail, or anything you may have printed, including private information, could be traced to you on basis of "It smelled bad" a la' current Stop-And-Frisk laws of the NYPD.
In case you are about to call me paranoid, the people that thought the PATRIOT would pass through congress were considered the same.
Genius may have its limitations, but stupidity is not thus handicapped.
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'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Jefferson is rolling over in his grave.
So what happens if you register your printer purchase and then sell it to someone else? Do you now have to worry about getting raided if the purchaser uses it for counterfeiting? I imagine the Secret Service would figure out what printer the documents came from, figure out who originally bought that printer and make the incorrect assumption that the original purchaser is the counterfeiter.
Why are we putting Big Brother in our devices instead of designing currency that's hard to counterfeit?
The feed rollers are replacable and made out of pliable rubber, usually a synthetic foam rubber. It won't stamp anything.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
You know the government can compare fingerprints. The government can compare DNA. The government can match paper fiber samples and patterns. Compared to all the government can do right now, I'd say this ability is rather innocuous. First of all they have to find the original printer for one thing.
The Cheese Stands Alone.
The serial number can be encoded using steganographic techniques you will never 'see' the encoded string unless you have the magic Homeland Security decoder ring.
On a more prosaic level DIGIMARC allows photoshop users to embed a unique ID number within your image and if someone opens up your image with a DIGIMARC enabled tool alarm bells go off.
Anyone know where we can get some Diablo 630's or Okidata Microline 83/93's (printers too stupid to encode images)
So my enemies just need to just get a test print from my printer, hack my serial number into a printer of the same model, and start sending out threatening letters to senators?