[ExI] Quantum Entanglement (was: simulation)

[Eugen Leitl]

On Tue, Dec 18, 2007 at 11:06:25AM -0500, John K Clark wrote:

> It most certainly is not snake oil, nor does Schneier say so in the article

The commercial QC products have however a strong taste of snake oil, 
and Bruce Schneier does indeed blast several crypto snake oil salesmen
(not difficult to find in the search term I posted).

> you mention, nor is he even talking about Quantum Cryptography in that
> article. However Schneier DOES  talk about it in his book "Applied
> Cryptography"; from page 554:

The book is from 1996. No QC products were available at that time on
the market. No dubious claims needed to be disputed.

http://www.schneier.com/crypto-gram-0711.html#5

Switzerland Protects its Vote with Quantum Cryptography

This is so silly I wasn't going to even bother blogging about it. But the sheer number of news stories has made me change my mind.

Basically, the Swiss company ID Quantique convinced the Swiss government to use quantum cryptography to protect vote transmissions during their October 21 election. It was a great publicity stunt, and the news articles were filled with hyperbole: how the "unbreakable" encryption will ensure the integrity of the election, how this will protect the election against hacking, and so on.

Complete idiocy. There are many serious security threats to voting systems, especially paperless touch-screen voting systems, but they're not centered around the transmission of votes from the voting site to the central tabulating office. The software in the voting machines themselves is a much bigger threat, one that quantum cryptography doesn't solve in the least.

Moving data from point A to point B securely is one of the easiest security problems we have. Conventional encryption works great. PGP, SSL, SSH could all be used to solve this problem, as could pretty much any good VPN software package; there's no need to use quantum crypto for this at all. Software security, OS security, network security, and user security are much harder security problems; and quantum crypto doesn't even begin to address them.

So, congratulations to ID Quantique for a nice publicity stunt. But did they actually increase the security of the Swiss election? Doubtful.

http://www.economist.com/displaystory.cfm?...
http://www.itwire.com/content/view/14833/53/
http://www.networkworld.com/news/2007/...
http://www.smh.com.au/news/World/...
http://feeds.arstechnica.com/~r/arstechnica/BAaf/~3/...
http://cwflyris.computerworld.com/t/2191514/92085/...
http://technology.newscientist.com/article/...
Me on quantum cryptography:
http://www.schneier.com/crypto-gram-0312.html#6

Me on voting:
http://www.schneier.com/crypto-gram-0411.html#1
http://www.schneier.com/crypto-gram-0411.html#2
http://www.schneier.com/crypto-gram-0312.html#9
http://www.schneier.com/crypto-gram-0012.html#1 
 
> "Quantum Cryptography taps the natural uncertainty of the quantum world.
> With it you can create a communication channel where it is imposable to
> eavesdrop without disturbing the transmission."

My copy is away at work, but if he said that he was wrong.

http://space.newscientist.com/article/dn2111-quantum-cloning-nears-perfection-limit.html

etc.

It is important to use holistical analysis of security claims
in order to evaluate them. Just pointing and muttering "entanglement"
"secure by physical law" is not only highly misleading, it is outright
wrong in some cases.

-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
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