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Crypto with Epoxy Tokens, Glass Balls and Lasers
Anonymous Coward writes "Scientists from MIT and ThingMagic have collaborated and developed an innovative crypto mechanism using epoxy tokens, glass spheres and lasers. They have actually created a physical one-way function that cannot be tampered, copied or faked! The full scoop can be found at MSNBC, and also at Nature, & TOI."
I think the process involved mixing a bunch of little tinfoil sparkles into a clear epoxy resin, applying the resulting glue as a seal, and photographing it from several angles. Simple to create, yet darn near impossible to duplicate a second time. If the blob is missing or different, something fishy is going on.
The thing about things we don't know is we often don't know we don't know them.
Can't be tampered with? Give me a hammer, I'll tamper with it... If I can't have the data, no one can!!!
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Programming is like sex... Make one mistake and support it the rest of your life.
One thing know once you read the article(s), that really should have been included in the story submisstion, is this technology is more geared toward replacing things such as magnetic stripes on credit cards, and em cards, and whatnot. The tiny crystals that will replace these stripes produce a one-way function that is currently impossible to duplicate, so if widely adopted this would (at least temporailiy) make card couterfitting impossible. It is not describing a new encryption mechanism for your PC, or any software for that matter.
I thought of that also. But I read the article more closely, and they mention that different view angles would be used to generate different speckle patterns.
A one-angle view of this token would not be secure, but a security mechanism that scanned the token through multiple angles would be very difficult to recreate. I don't know if they should be throwing around the word 'impossible', however.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
This seems like a really good system, one that for once is almost impossible to forge. However, it seems to have a major flaw: Durability. The Nature article states that "a token with a hole half a millimetre across drilled through it gives a speckle pattern clearly distinguishable from the original." So what happens when (not if!) the card gets scratched and worn? Will it immediately stop functioning? These secure cards won't be worth much if they have to be replaced every month because of wear and tear... and with the system they are using, error correction isn't an option (defeats the whole purpose of the tokens since tampering with them would then become possible).
McGuyver has made plans to begin work at MIT in their research department to create supercomputers from old ballpoint pens, and outdated telephone mechanisms.
If you're looking here for something insightful or thought provoking, you're probably looking in the wrong place.
actually, i have 3.
there are 50 or so of em lying around at home, making my wife mad.
so explain again why guitar picks are news?
(my apologies to westsky in advance)
guns kill people like spoons make Rosie O'Donnell fat.
Cheap trick secures secrets
Finally! Something to go hand-in-hand with my REO Speedwagon encryption algorithm.
Where does the school board find them and why do they keep sending them to ME?
And all these years my family has been persecuted in Salem, MA and it turns out all they wanted was our crystal balls!
will bill this as "Cryptography with balls."
I recall reading something very similar in I believe Scientific American (which is not searchable, unfortunately), oh, ages ago. Used to identify ICBMs / warheads / other missiles during arms reduction discussions between the US & Russia (might even have been so far back as to make that USSR). Basically a splash of epoxy with sparkles mixed in on some disasterously-expensive-to-replace part of the device, snap a photograph and/or hologram, and the device is reliably tagged.
... unless of course Fritz [Hollings] gets his palladium-plated way and we at some point do get tamperproof, "trusted" hardware (... to play around with - I'm looking forward to that).
... it raises the price of duplicating a unique physical dongle.
... what was the author of this /. article taking? I want some.
So it's become cheaper, cheap enough even for everyday use. However, the possible uses I can see are rather limited: local authentication, and pretty much nothing else.
It's good for credit cards, but only if the card is physically read by the entity requestion authentication, and only if that entity is online (or has a local database of the speckle pattern of all cards worldwide, plus a magically updated revocation list).
For any non-local authentication it doesn't seem much good
So
But it definitely has nothing to do with crypto (i.e. encryption)
yes, we have no bananas
This is an improvement on an idea from the 1980s called "quantum subway tokens". There have also been a few schemes involving 2D speckle patterns as unique, hard to forge data items. But they're not challenge/response, like this. Challenge/response devices exist (Sun's Java-powered jewelry, the Dallas Semiconductor button) but they're more complex. On the other hand, their readers are simpler than this optical system will require.
The useful advancement in this thesis is in section 5.3.4, where the authors demonstrate that the registration of the scanning beam doesn't have to be extremely tight. You'd think this scheme would involve optical-bench precision, but it doesn't. (Well, actually it does, but not wavelength-precise optical bench precision. Still, it involves micrometers driven by computer-controlled stepping motors and a very rigid fixture. It's not a "just swipe the card" system.)
The trouble with this system is that there's no public key associated with the object - only a huge number of possible challenge/response pairs. Validation at an untrusted reader is done by probing the object using challenges previously performed at a trusted reader. Those challenges are "used up" as the object is validated, because otherwise, they could be replayed. This is much less convenient than a public/private key system. It's more like one of those systems where you have a wallet card with a long list of challenge/response pairs for logging in. The only advantage here is that the object isn't copyable. It's still stealable, of course.
It's kind of neat, but probably not commercially useful.
Also, if the connection between a store and the pattern validation server is ever intercepted, a hacker could just save your patterns and re-send them whenever they want to purchase pr0n or something. So I think the original poster was right: this is just like stealing credit card numbers. As long as validation is done by passing around a bunch of digital data, that will always be the point of weakness. Even now, the vast majority of credit card fraud happens not because somebody's magnetic strip gets duplicated, but because somebody's credit card numbers get stolen. It seems like making the physical cards harder to duplicate is barking up the wrong tree.
The only solution I can see is this: There wouldn't be a unique resultant diffraction pattern that gets passed around, but rather a two-way conversation between the validation server and the card reader. The server would ask three random questions of the sort "what pattern is produced when the laser shines from angle 1, what about angle 2, etc. The problem with this is that the validation server would have to know what the right answers are to all of the possible questions, and that creates a problem: either there would be waay too much data stored for each card, or there would only be a limited number of "questions" the server could ask. In the latter case, a thief's computer could just memorize all the answers to the few questions, and produce them without the card whenever the validation server actually asks.
Yeah, I agree. That band sucks.