Comment by chimeracoder | Hacker News Reader

Comment by chimeracoder | Hacker News Reader

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IANAL, but IMHO, the only reason that snail mail is more secure/private is due to the laws that protect snail mail (extensive), versus the laws that protect your email inbox (nonexistent).

Keep in mind that the USPS can (and does) scan the front and back of envelopes[0]. Keeping this information indefinitely is tantamount to storing email "metadata" (information which is intrusive enough that it's what caused Groklaw to shut down).

Also, it's easier than one might think for a determined adversary to discern the contents of the letter - either by opening it carefully so that it appears unopened, or by (e.g.) shining a light to

There are defenses against this too, but I wouldn't assume the physical post is inherently more secure than email.

[0] http://www.nytimes.com/2013/05/04/us/where-mail-with-illegib... - I can't find the original link that asserted that they store this information indefinitely, but IIRC the USPS didn't make much of an effort to hide it.

Yes, pmail is strictly more secure than email (noting that nothing is 100%, blah blah). A letter contains less metadata than email - only the recipient address needs to be valid, where "validity" means "corresponds to a deliverable address" with no requirement that it correspond to a particular identity. Merely observing the contents, without triggering your tamper-evidences, requires at least semi-skilled labor. This labor needs access to the physical letter, which means the USPS at some point is directly involved in cooperating & keeping their mouths shut. Notably, applying all this takes the adversary more time per interception than it takes you to write another letter. The contents can still be encrypted regardless.

Do not make the perfect the enemy of the better. This is the kind of thinking that gives us big scary warnings for self-signed SSL certificates, and lets plain HTTP connections proceed unmolested.

This is a pdf for a camera that has the same sensor as is used in mail sorting equipment. http://fairchildimaging.com/files/2kand4klvcameramanualrevc_... Here is the equipment in action. https://www.youtube.com/watch?v=2ynZ4klX2BE

I never built mail sorting equipment, but I did work with that camera quite a bit. It has very good sensitivity. For a lark one day, I decided to see if I could read mail through the envelope. So, I fed some junk mail in front of it and found that for non-privacy type envelopes, it was almost as easy to read what's inside (top page) as what was on the outside of the envelope. Multiple pages stacked and folded made it impossible to read everything, but you could have read the outer page portion of a tri-folded letter on each side. Keep in mind that I implemented this for fun on a slow afternoon (and it required no special wizardry). Given time and resources, maybe a second camera or different lighting, a lot more might be achieved. Even a naive approach of scanning a letter multiple times under different lighting conditions might be enough to read a large fraction of letter mail. It would take less than a minute. It would not require opening or touching the letter more than an ordinary mail sorter.

Now I am not alleging that I think that all mail is stored/read, but I am saying that the tech needed to do that to some degree exists and is at least partially in place.

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