Slashdot Mirror
Relativity Used to Devise New Form of Crypt
Cebert writes "CNN.com posted an article about using relativity to create a new form of encryption. The new encryption allows an individual to make a prediction with a guaranteed date stamp that only they can reveal. " Hmmm...quantum predictions. Yeah, I guess that's hard to crack.
The article is a little short on facts. Here are a few more details:
ABSTRACT:
Unconditionally Secure Bit Commitment
Adrian Kent
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, United Kingdom
(Received 13 July 1998)
We describe a new classical bit commitment protocol based on cryptographic constraints imposed by special relativity. The protocol is unconditionally secure against classical or quantum attacks. It evades the no-go results of Mayers, Lo, and Chau by requiring from Alice a sequence of communications, including a postrevelation verification, each of which is guaranteed to be independent of its predecessor. ©1999 The American Physical Society
Here are copies of his article in pdf and in gzipped PS.
I
Is there a perl module for this yet?
required username/passwd...and no, cypherpunk/cypherpunk did not work.
Or is it yet another ploy to get us all excited for nothing?
I've read too many of the pie-in-the-sky things that I think I am becoming more and more cynical by the day.
Muchas Gracias, Señor Edward Snowden !
Sounds like bullshit. I don't doubt the physicist came up with something possibly good. It's just that it almost certainly was screwed up by CNN+slashdot in reporting.
Here's the preprint in ps from LANL, instead; only institutional subscribers have access to the PRL online article.
I read from the article (e.g. the Postscript version of the original article on LANL), that this protocol can only be used to secure real time communications only.
The protocol cannot be used for email or file encryption. With this protocol one can only make sure, that the line you are currently using is secure.
As timing is a critical of the security mechanism, standard internet with nondeterministic transmission times does not qualify for this protocol.
Nonetheless an interesting article (and as "smooth" to read as any other scientific article).
#define rant_mode
A classic case of hearsay (=RTFM failure) and media hype.
#undef rant_mode
Admittedly, I was a tad sceptical about all this but it does seem to be right. For real-time communications only, of course.
A caveat: If there exists a wormhole between A and B such that the time taken from A to B is 'subverted' to be smaller than expected, the whole system breaks down.
So in effect, you have to check that the local space between A and B is Minkowski-like before communicating. Or just trust!
Well -- yeah. It works because nothing is revealed until everything is revealed, as it were. It collapses to the concepts: 1)that you can't decrypt a message until you receive all the bits of it + 2)one-time pad. It introduces the additional complication of communication between users (that's where relativity comes in -- the light cone limits transmission speed, but the authors very gracefully fold in the idea of quantum communication and classical communication being identically undecryptable under this protocol.) Clever, but [currently] useless.
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DNA is a Turing machine. You, however, being dynamic and emergent, are not.
Contrary to the report, this doesn't encrypt anything: it's a "bit commitment" protocol, allowing me to irrevocably choose one of two choices without revealing what I chose later. One application of this is fair coin tosses: you and I both choose a bit at random, then reveal them once they're chosen, and if they're the same I win otherwise you win. The commitment protocol stops me waiting until you've revealed your choice and then announcing that mine is the same.
As another poster said, in practice SHA message digests can be used to do the same job more practically, but this offers "unconditional security"; no amount of computing power could be sufficient to break the protocol.
--
Xenu loves you!
Pete.
Unfortunately, this scheme presents a problem, because when using quantum encryption, it is not possible to know both your user name and password at the same time.
/bin/cat.
Not to mention the fact that someone keeps killing
If, however, you look and find that it is dead, simply get enough other people to look until one of them sees it alive, then the whole problem is solved. At least, according to this one sci-fi story I read, it is, I think. Or, you could go the Dirk Gently route, instead.
If implemented, this form of encryption would be infallable. My relatives can't even turn on a computer, let alone decode high level encryption.
It is strange how oftentimes the air speaks. We are sane as long as we hear voices where there are none. We are insane when we hear nothing, and worse, we are
Indeed.... a most interesting observation.
Of course, hearing nothing when we are "hearing" something could be attributed to deafness...
Insert mind here.
> Not to mention the fact that someone keeps killing /bin/cat.
/bin/cat is in superimposition of states and so works OK. As soon as you check, the wave function collapses and you have a chance of getting a dead /bin/cat!
/bin/cat without any problems -- nothing more serious than forking of the whole universe is likely to occur.
Actually, I'm not sure whether mine's dead or alive. I'd better go check...
Don't go and check! Until you look your
Disclaimer: this assumes a Copenhagen interpretation. If you like multiple universes better, you can check your
Kaa
Kaa
Kaa's Law: In any sufficiently large group of people most are idiots.