
‘Unbreakable’ quantum cryptography hacked without detection using lasers - nickb
http://www.tgdaily.com/content/view/39599/108/
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tptacek
I stopped reading at "quantum cryptography is used to secure Swiss bank
transactions". The highest conceivable levels of finance are protected using
nothing more exotic than SSL/TLS. I'm sure there's an awesome paper buried
somewhere in this story, but I'm equally sure this reporter has no idea what
it means.

~~~
nihilocrat
Scroll up a bit, by the looks of the comments it seems like it's another case
of "clueless journalist makes a hokey-sounding story about a real technology".

This is why I don't generally ever read online articles about technology
written by 'normal' news outlets.

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hugh
Almost certainly either:

a) Complete BS, or

b) Not what it sounds like, but

it's not possible to figure out which from this article, which provides no
information. If anyone has a link to a better explanation, I'd love to read
it.

The closest thing to a clue is this vague statement:

 _The intruder simply hooks into what the receiver is receiving (which is
actually very complex)._

which sounds to me like the intruder is, in essence, looking over the
receiver's shoulder.

~~~
hugh
Aha, I found the paper:

<http://arxiv.org/abs/0809.3408>

It's all about exploiting vulnerabilities in the type of single-photon
detectors that are used in real systems. Looks like pretty clever stuff.

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RK
Maybe michael_nielsen can give us some insight on this story.

~~~
michael_nielsen
Not much to add beyond what's already been said. The linked article isn't very
good, but the paper itself may be correct. I haven’t checked the paper, but
the possibility of this kind of break is quite plausible. The reason is that
when quantum cryptography researchers say quantum cryptography is
"unbreakable", there’s many unspoken caveats. All they mean is that the
theoretical scheme itself is unbreakable. Of course, (a) the real-world
implementation may differ in subtle ways from the theoretical scheme; and (b)
side-channel attacks cannot be ruled out. Both these possibilities can
potentially be exploited to crack quantum cryptography. I’ve written about
this at some length at: <http://michaelnielsen.org/blog/?p=122>

If you feel a bit cheated by this state of affairs, given the hype that often
surrounds quantum cryptography, I don’t blame you.

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tlrobinson
Sooo how exactly does this work? The article seems to be a bunch of
handwaving.

~~~
nickb
See: <http://news.ycombinator.com/item?id=323856>

