RE: Scientific American on Quantum Encryption
I've actually seen these devices in operation. The thing that impressed me most was that the path need not be a single fiber from end to end - you can maintain quantum state across a switchable fiber junction. This means you are no longer limited to a single pair of boxes talking to each other. True, the SciAm article doesn't address a lot of issues, but the fact remains that this technology is interesting and important. Peter Trei
-----Original Message----- From: owner-cypherpunks@minder.net [mailto:owner-cypherpunks@minder.net]On Behalf Of Eugen Leitl Sent: Thursday, January 20, 2005 6:17 AM To: transhumantech@yahoogroups.com Cc: cypherpunks@al-qaeda.net Subject: Scientific American on Quantum Encryption
Scientific American has little clue, as usual (see their nanotechnology retraction).
Link: http://slashdot.org/article.pl?sid=05/01/20/0358215 Posted by: samzenpus, on 2005-01-20 06:35:00
from the just-try-and-break-it dept. [1]prostoalex writes "Scientific American claims that [2]advances in commercially available quantum encryption might obsolete the existing factorization-based solutions: "The National Security Agency or one of the Federal Reserve banks can now buy a quantum-cryptographic system from two small companies - and more products are on the way. This new method of encryption represents the first major commercial implementation for what has become known as quantum information science, which blends quantum mechanics and information theory. The ultimate technology to emerge from the field may be a quantum computer so powerful that the only way to protect against its prodigious code-breaking capability may be to deploy quantum-cryptographic techniques.""
What do you mean? By a physical fiber switch? That's certainly possible, though you'd need a very good condition switch to be able to do it. I'd bet if that switch switched a lot, the QCrypto channel would eventually be unusable. If you're talking about a WDM element or passive splitter or other purely optical component, then you'd need some kind of error correction (in the digital domain) in order to overcome the fact that many of the photons will not choose to go in the direction you want. In the long run I think we'll see some small proliferation, but given the level of integration and how well current coding schemes work, I'd guess this will remain a niche unless there's a major breakthrough in factoring. -TD
From: "Trei, Peter" <ptrei@rsasecurity.com> To: "Eugen Leitl" <eugen@leitl.org>, <transhumantech@yahoogroups.com> CC: <cypherpunks@al-qaeda.net> Subject: RE: Scientific American on Quantum Encryption Date: Thu, 20 Jan 2005 10:47:38 -0500
I've actually seen these devices in operation. The thing that impressed me most was that the path need not be a single fiber from end to end - you can maintain quantum state across a switchable fiber junction. This means you are no longer limited to a single pair of boxes talking to each other.
True, the SciAm article doesn't address a lot of issues, but the fact remains that this technology is interesting and important.
Peter Trei
-----Original Message----- From: owner-cypherpunks@minder.net [mailto:owner-cypherpunks@minder.net]On Behalf Of Eugen Leitl Sent: Thursday, January 20, 2005 6:17 AM To: transhumantech@yahoogroups.com Cc: cypherpunks@al-qaeda.net Subject: Scientific American on Quantum Encryption
Scientific American has little clue, as usual (see their nanotechnology retraction).
Link: http://slashdot.org/article.pl?sid=05/01/20/0358215 Posted by: samzenpus, on 2005-01-20 06:35:00
from the just-try-and-break-it dept. [1]prostoalex writes "Scientific American claims that [2]advances in commercially available quantum encryption might obsolete the existing factorization-based solutions: "The National Security Agency or one of the Federal Reserve banks can now buy a quantum-cryptographic system from two small companies - and more products are on the way. This new method of encryption represents the first major commercial implementation for what has become known as quantum information science, which blends quantum mechanics and information theory. The ultimate technology to emerge from the field may be a quantum computer so powerful that the only way to protect against its prodigious code-breaking capability may be to deploy quantum-cryptographic techniques.""
On Thu, Jan 20, 2005 at 10:47:38AM -0500, Trei, Peter wrote:
I've actually seen these devices in operation. The thing that impressed me most was that the path need not be a single fiber from end to end - you can maintain quantum state across a switchable fiber junction. This means
Very impressive. If they manage to keep the entanglement all the way up to LEO by line of sight it would be even more impressive (anyone thinks this can be done at all?)
you are no longer limited to a single pair of boxes talking to each other.
What makes it very important is early beginnings of practical quantum computing. Will photonics and spintronics in solid state at RT play well with each other? Will error correction scale to large qubit register sizes? Will the algorithm space be large and rich enough to be practical? All very interesting questions Scientific American fails to raise.
True, the SciAm article doesn't address a lot of issues, but the fact remains that this technology is interesting and important.
I agree that this technology is interesting and important, but not for what it claims to be used for. Quantum encryption right now is a tool to milk the gullible, and hence very much crypto snake oil. For these distances one-time pads by trusted couriers would seem so much more practical and so much cheaper. -- Eugen* Leitl <a href="http://leitl.org">leitl</a> ______________________________________________________________ ICBM: 48.07078, 11.61144 http://www.leitl.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE http://moleculardevices.org http://nanomachines.net [demime 1.01d removed an attachment of type application/pgp-signature]
participants (3)
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Eugen Leitl -
Trei, Peter -
Tyler Durden