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Quantum Cryptography Gets Nanotube Boost
c1ay writes "In an article at the ScienceDaily News it is reported that two researchers at the University of Rochester have discovered a new property of carbon nanotubes, ideal photon emission. "The emission bandwidth is as narrow as you can get at room temperature," says Lukas Novotny, professor of optics at Rochester and co-author of the study. Such a narrow and steady emission can make such fields as quantum cryptography and single-molecule sensors a practical reality. RSA and Elliptic Curve wouldn't stand a chance against this unbreakable encryption."
Quantum cryptography is very interesting--an absolutely bizarre manifestation of one of the most spooky and anti-intuitive features of quantum mechanics. The very premise gave Einstein fits.
But where RSA is used (and, barring an as of yet undiscovered in the open world weakness, elliptic curve cryptography) quantum cryptography has no application.
Quantum cryptography is built on the quantum entanglement of photon pairs, who's wave function must remain un-collapsed by measurement or perturbation until decode. This feature is both quantum cryptography's strength and weakness:
It's a strength because any Eve eavesdropping is irrefutably revealed.
It's a weakness because it limits the applications to such Alices and Bobs where between actual original photons may be reliably transmitted.
RSA and various other "Newtonian" cryptographic schemes make use of mathematical transforms rather than physical properties of individual particles and survive re-transmission with their essential properties intact; for example, over a packet switched network.
What RSA may not ultimately stand a chance against are quantum computers, which according to a variation of Moore's law I might have been the first to state (at DEFCON 9), will within a decade surpass then available classical computers and will (in theory) be exceptionally good at cracking encrypted documents.
Assuming the NSA doesn't already have a good working quantum computer...
And assuming it's possible to continue adding entangled qubits...
Anyway, Moores law says the power of classical computers increases as 2^(Y/1.5), where Y is years. So far, roughly, quantum computers are increasing in power as 2^2^(Y/2), which should make em about 10^225 times as powerful as today's classical computers in 2 decades, and if that turns out to be so, then RSA really won't stand a chance. It might be a bummer for some: 4096 bit PGP keys are assumed to be safe against, for example, the combined efforts of all computers to be built according to Moores law between now and any normal lifetime, or at least well past the statute of limitations. But if quantum computer development continues apace, that assumption may be problematically flawed.
But it's not quantum encryption that's the threat, it's quantum computers. Quantum encryption isn't any more unbreakable than whatever data method underlays it, though it's a fine way to transmit a stream of random numbers. The "key" is that it is, apparently, physics-ally impossible to intercept the stream of photons without causing a measurable effect. So Alice and Bob can be absolutely sure their one time pad is known only to them...
as long as no one is looking over their shoulders...
All this talk about cryptography sure is sexy, but how about something practical, like a computer monitor with resolution so high you can't even see the pixels? I want a screen that is indistinguishable from a sheet of paper.
Noone has ever created a One time Pad plugin for outlook.
Think about it. Create a random one time Pad of a few hundred MB. Burn it on 2 cd-r. Put one in your safe and hand the other to BOB in person.
Now just use the pad piece by piece for your secure transmissions. It should last for years if you dont sent porn or warez....
As long as you use every part of the pad only once, even if the attacker gets the plaintext of one message the others wont be compromised.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?