Hacker News Reader

Comment by rurcliped | Hacker News Reader

Possibly because the firmware could be modified, and not print the required yellow dots or other tracking data:

https://www.eff.org/pages/list-printers-which-do-or-do-not-d...

"Some of the documents that we previously received through FOIA suggested that all major manufacturers of color laser printers entered a secret agreement with governments to ensure that the output of those printers is forensically traceable."

View on HN

Nothing in that article suggest that open source firmware needs to print the yellow tracking dots, or that that feature can’t be disabled by users.

I think that's the reason it doesn't exist.

The yellow dot feature doesn't exist? It most certainly does. You can see this yourself by putting a darker ink in place of the yellow in your printer.

No, they're saying the reason open source firmware doesn't exist is because doing so could allow you to not print the dots when printing.

Out of curiosity, why couldn't I make a printer driver that always sent the printer data with some extra yellow dots scattered around, in an arrangement that would make the tracking codes illegible?

Perhaps the yellow dot is placed slightly off from the axies of the standard grid, making it unforgeable through input data-- I'm not sure that's what they've done, but surely they have to have considered input sanitization to some degree

I think it would be tricky to ensure that your dots were in valid places that the tracking dots could be.

If you want to print a bomb threat or whatever it would be easier to use a black and white printer, or just fill the whole page with yellow.

The firmware would make sure the significant yellow dot patterns would be recognisable by not printing some of those yellow dots you tell it to print. As long as the firmware has the final say on what ends up printed there is no way you can avoid those watermarks no matter how cunning your scheme is. Stalin was right when he said "It's not who votes that counts, it's who counts the votes" - this is just as applicable here: "It's not who orders the print what counts, it's who prints the order".

That's exactly how countermeasure software works. I believe it was both the EFF and CCC that developed counteractive software for this after initially discovering it (correct me if I'm wrong).

So what happens to people who try to make open-source firmware? They get a secret cease and desist slash gag order?

Some men in suits and black sunglasses showing up at their door...

My B/W laser printer doesn't have a yellow toner cartridge. How are the yellow dots printed?

The article clearly states that the yellow dots are printed by _colour_ laser printers.

they are worried about currency forgery.

Haha, that didn't cross my mind. For some reason I thought they were concerned about ransom notes (facepalm.png).

> output of those printers is forensically traceable

Are similar techniques used in 3D printers?

Given that there is open source firmware for 3D printers, I’d say no. Also, the “resolution” of 3D printers is not high enough to allow for a tell tale “mark” that was otherwise undetectable.

Also you can't 3D print bank notes.

I mean you can't laser print bank notes either, not just because of the EURion constellation [1], but because they look and feel literally nothing like bank notes. I honestly never understood the imeptus.

[1] https://en.wikipedia.org/wiki/EURion_constellation

Oh, you can absolutely laser print bank notes. It used to be a thing in the 90s, either with color laser printers or color photocopiers. Of course, they're absolutely horrid fakes.

Now, the only person dumber than a criminal who would think to try this is a store clerk who would accept these. So it is not an effective crime, unless the effect you want is "jail, quickly". But it is nonetheless a real crime.

In the 90s it was easy cos it wasn’t wide spread so easy to get away with.

> Now, the only person dumber than a criminal who would think to try this is a store clerk who would accept these.

Not always - it'll often be safer just to accept the "money" and contact the police directly afterwards.

Generally counterfeiters will strip the ink from a $1 bill and print a $20 or $50 on it. This way it feels like real money. It is easily detectable if you hold it up to the light, but a cashier might not notice it right away.

No. How would that work?

Reply on news.ycombinator.com