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Comment by ajays | Hacker News Reader

FTA: "There’s another option I didn’t originally mention here — leaking over mail. Investigative journalist Julia Angwin of the Wall Street Journal points out that physical mail, dropped in a random post-box with a bogus return address, is perhaps the best way for anonymous one-way communication."

DO NOT DO THIS! Every printer leaves a microscopic fingerprint on every printout. The printouts can be traced back to your printer. If it's an office printer, that still narrows it down considerably.

Even electronic documents can have watermarks, etc. For photographs, there's the EXIF information, for instance. If you want to share a photo, pipe it through "djpeg | pnmscale 0.99 | cjpeg -quality 90" first. It will get rid of EXIF, and also re-compress the image, changing its signature.

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Interesting, I didn't know about printer fingerprints.

But I think there are still ways to workaround this. You could print the doc in an internet cafe, or buy a cheap printer and then destroy it, or print it and then take a low quality photocopy. You could even write it by hand or on a typewriter.

"buy a cheap printer and then destroy it"

Have somebody else buy it with cash only. Surveillance cameras catching you with a printer and then not able to explain where it went will not go well.

I can't believe I actually am saying this. I truly can't believe that we are all having these kinds of conversations about something that should be as trivial as telling the truth. This is the kind of stuff I imagine the Russian mob would do, not employees of the US government who have a conscious. It is truly despicable and makes me a bit nauseated. The worse part is there doesn't seem like a fix and there doesn't seem like there is anywhere else to go to avoid this.

A photocopier is a (scanner+printer), so the problem remains.

Your best bet is large flea markets, where you can buy stuff like WiFi dongles, etc. with cash. Then wait a while before you use them.

I can't believe I'm having to write this, either. This is like giving instructions to a Soviet activist in the Cold War days, but ironically it is in my own country. How did we fall so far?

> How did we fall so far?

Fall? You'd have to give the same instructions to a Soviet activist in the Cold War days here.

I should mention that actual watermarks in digital media (images, audio, video, etc.) will not be removed by recompressing the media. These watermarks are specifically designed to remain readable through compression and simple transformations. This technology is widely available commercially, so presumably the government has even more robust versions.

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