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Practical Quantum Cryptography
Alien54 writes: "Saw this on Eureka Alert: A commercially available system for quantum key distribution and cryptography has been released by a spin-off company from the University of Geneva. The system has been tested over distances up to 70km (from Geneva to Lausanne) through standard optical fiber cables and connects to PCs via USB ports. Transmission rates of about 60 bits per seconds were achieved, sufficient for key distribution. You can see the original abstract here, which also has a link for download of the paper in PDF, Postscript, and other formats."
Neato. When we get a "Quantum Crypto IP Backbone" that will be cool.
Of course QC is really only secure when they are direct connections. So if we want to use routers and switches to make connectivity practical we will lose the security.
This type of thing would be cool for businesses and such that want a secure connection with other branches or offices. They could do a token ring style idea where they relay from their own branches to reach a wide area.
Tom
Someday, I'll have a real sig.
Was it a spin-off company, or perhaps just a spin-up or spin-down company?
As nice as this scheme might be compared to previous quantum cryptography schemes, there are still fundamental problemns with implementing quantum cryptography. First off, you need a single, otherwise unused optical fiber to connect the two boxes. This means running your own cable. There's really no way around that. You're not going to find unrepeated, unused fiber just lying around.
vi is my shepard, I shall not font.
The conclusion of the article states that the system is currently commercially available. Here is a link to the QKD System.
-- Find the Truth...
I'm going to go out on a limb here and guess that the result of that equation is the number of times you've been turned down for a date?
--
I Hit the Karma Cap, and All I Got Was This Lousy
I wonder if it's legal to import these things to the united states?
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Play Six Pack Man. I
I found a site that explains why classic cryptography suffers when compared to the benefits of quantum cryptographic methods.
The site is located at http://www.qubit.org/intros/crypt.html, and is part of the Center for Quantum Computation (Oxford University).
Here's a nice basic overview of QC from the site mentioned above: "While classical cryptography employs various mathematical techniques to restrict eavesdroppers from learning the contents of encrypted messages, in quantum mechanics the information is protected by the laws of physics. In classical cryptography an absolute security of information cannot be guaranteed. The Heisenberg uncertainty principle and quantum entanglement can be exploited in a system of secure communication, often referred to as "quantum cryptography". Quantum cryptography provides means for two parties to exchange a enciphering key over a private channel with complete security of communication."
Linux > Help > About
pw:secret
You probably recall how quantum computation works: essentially you shove all the extra computation off into parallel universes and then get the answer back when it comes. Why not expand on that idea and use quantum file storage? The RIAA can create CDs where only part of the audio track exists in our universe and the rest is retrieved from parallel universes by your quantum audio system. This makes file copying mathematically impossible.
Now someone is probably going to pop up and say "well, I can pirate the signal after it has been revirtualized from the quantum foam". I'm glad you brought that up because it leads right into phase two of my idea. In order to listen to music, all consumers would be have sound-decoding chips implanted in their brains. The music would be beamed directly into your head from your audio system.
Thus we see that file copying can be made impossible by those that are willing to pay the price of our freedom. The only solution is to keep quantum computers from becoming a reality
Not nearly secure. Physics protects this communication from straight interception. However, it does not protect it from interception and then retransmission. But cool buzzwords. They'll make a little bit of cash before the con is up.
put that one in the NSA's pipe and smoke it.
Great...all my encryption problems are solved!!! And not a moment too soon, either...
:-)
After all, I was getting a bit nervous with respect to my encryption needs in light of the retirement of further development of PGP and the possible inadequacies of GnuPG...
Beer is proof that God loves us and wants us to be happy. -- Benjamin Franklin
Well, I wasn't too sure, so I dug up some links to try and help myself and others understand this:m /quantum-index.html
http://research.microsoft.com/~gottesma/QKD.html
http://www.qubit.org/intros/crypt.html
http://www.ecst.csuchico.edu/~atman/Crypto/quantu
The last link is particularly +1 insightful about the basics of quantum cryptography.
I posted to
Home Page here:
www.idquantique.com/index.html
"It is a greater offense to steal men's labor, than their clothes"
Now someone is probably going to pop up and say "well, I can pirate the signal after it has been revirtualized from the quantum foam". I'm glad you brought that up because it leads right into phase two of my idea. In order to listen to music, all consumers would be have sound-decoding chips implanted in their brains. The music would be beamed directly into your head from your audio system.
Thats a very good point. Quantum cryptography is essentially a form of One-time pad cryptography, which is an algorithm that uses a completely random assortment of characters as the key, and each key is used only once. This type of cryptography is said to be absolutely unbreakable, and in a realistic sense this is true. However, using brute force one can decode the possible message, but included with that you will get every other possible message that is of the same length as the encrypted message. This is what makes quantum cryptography so secure.
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Striving to put right what once went wrong, and hoping each time that his next leap, will be the leap ho
Are those spelling mistakes OCR typos or a secret embedded message? Oh well, noticed it now, I guess the gig is up.
It only comes in three colors.
What makes the transfer secure is that the two parties involved don't reveal their polarizer settings until AFTER the bits have been transferred. By which time, it's too late for the "man in the middle" to go back and change his answers.
It's really quite clever...
-Mark
if anyone wants to read more look for this book which covers the history of cryptography from ancient egypt to quantum cryptography...i read it, and it was extremely interesting from a mathematical and computer point of view...it includes a whole section of the theories behind quantum computing and quantum cryptography...
"Facts are meaningless. You could use facts to prove anything that's even remotely true." - Homer Simpson
And I just bought a newtonian key distribution system! The vendor told me quantum mechanics was nonsense.
... "Give me a woman who loves beer and I will conquer the w
Still pay more money? [laugh] "Only the little people pay taxes."
But how do you know who the recipient is? QC offers no authentication. If you have to use public key for authentication, what advantage is gained by using superior methods for confidentiality?
The only one I can think of is that, with conventional cryptography, you can capture the data stream and crack it "off-line". I suppose that this is significant: with QC you only have to worry about whether they've cracked your private key (that you will use for authentication) already, not whether they can in 100 years (because you've used it for encryption).
Another argument might be that it is easier to eavesdrop on a channel than to redirect it. But that seems like a dubious assumption, if the enemy is determined.
Thoughts?
The evaluation of an action as 'practical' . . . depends on what it is that one wishes to practice.
A while back there was all these studies and experiments about duplicating light beams. I recall mentions of quantum entanglment and such (stuff that's used in these secure quantum transmision schemes).
Could one of these duplication beams be used w/out being detected? I know normal reception and retransmission IS detectable.
"this is useless you linux fags!" They have linux on packets of cig's now?
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
However, like many of their announcements, they couldn't place a time or date when it would be released...
IANAL, but I've seen actors play them on TV
I certainly hope not. Most of the philosophisizing about quantum mechanics that makes its way into popular books is crap. They miss the crucial distinction between "unknown" and "indeterminate," and in so doing give quantum mechanics some spooky relationship with consciousness or a universal oneness that it just doesn't have.
Schroedinger's cat may have sacrificed its life to make this product a reality. Or maybe not. Only Heisenberg knows for sure.
Using a 60bps channel to send a 3600bit key would take one minute. Encrypt the data to be sent via conventional high bandwidth transmition with that 3600bit key for one minute, meanwhile send another 3600bit key via the 60bps channel. Or if 3600 bits is not secure enough for you, use an even larger key, sent over a longer period of time.
Alternatively, send a 60 bit key every second for a 8092 bit key embeded in the high bandwidth data stream, use the 8092 bit key to decrypt the next second's block of data.
The important part is to understand that only the sender and the recipient have the keys. As I understand it the process itself is generating non-crackable keys.
Then again, I could be wrong.
-Rusty
You never know...
Man, you made my day. This may lead some to wonder how boring my day is. It's pretty boring.
"RIAA can create CDs where only part of the audio track exists in our universe..."
I would bet this appeals a lot to RIAA. But why stop there? From what I understand they're looking for a way to sell you the CD so that there's actually no music on it.
Perhaps just a recording of one of the executives in charge saying "Thank you for purchasing this digital music container device. We assume that you have a computer and have downloaded countless megabytes of our copyrighted material. Therefore, we have pre-removed the equivalent amount of data from this CD. Enjoy." Followed by 71 and 3/4 minutes of silence.
Sweat
It breaks my pluginses, my precious!
yeah, I know a guy that got fired from his job at Boeing for proving that his anti-gravity system worked. Boeing wanted non of it, told him that 'This company obeys the laws of physics'.
Can you direct us to a page with his proof on it? From what I've seen if Eve is trying to listen, then both ends know about it and can send a bouncer type to go kick Eve's ass off the line...If your friend can provide an example of how QC can be broken then I think all of slashdot would like to hear it. (the rest of the world is unimportant)
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
Some philosophizing is that crass its true, but if you actually read Penrose or Zohar they're not playing off on the "indeterminacy" "mystical" cheap shot, they're actually examining how the underlying reality model of quantum physics does encourage a more holistic interconnected view of things where multiple effects are complexly related to multiple causes, at some times unbounded by traditional constraints on space and time.
To me it works against mysticism by drawing into rational frameworks of thought phenonema like consciousness which are impossible to analyse comprehensively within the framework of Newtonian mechanistic physics.
Like many "alternative" things being forced to exist on the fringes of mainstream thought attracts the kooks who habituate those fringes. So yeah some of its crass - read the good stuff.
F4RVVMI0-4MV4K3-GNJWRLNVUWILSNVH47 TP9MTJ894PW3MJSK4L;M49TIMAJK TMVAKL;TMAW4K950[MAWVK9T[MK9PUD56MO/8NK 4SW-90A-94 8I3E-90 9Y5-4]Y59S,BOKSY;'5GB L; YL;SE,L YR;E'KAO P34[I693 A[90[ ZGFKGL;/ ,GL;D'F KGLSDF;'G DSFG,DFLG;D L; C3D1JKCN00892N5VFKLMD31NOV VTN5UIONT
And that completes our tour of Hilbert Space. Any questions?
Oh for crying out loud! Who let that cat in here? Now I don't even know what i said. That's one dead cat if I ever get my hands on it.
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Let me be honest as well, then. It is human nature for government bureaucracies to be sluggish, inhumane, and extremely corruptible. Why should the government of the good old US of A be any different? Your assumption that money would be better off in the hands of the government than in the hands of the people who made it is ridiculous.
A lot of government money ends up spent on socially destructive programs like welfare, or given out in "pork-barrel" contracts in order to strengthen some politico's bargaining position. And a lot of the government programs that are worthwhile, like NASA, get almost nothing.
So think before you call for bigger government. Most of the "big" governments of the twentieth century have not been nice places to live... or die, as the case may be.
"Any connection between your reality and mine is purely coincidental." -Slashdot
And what happens when someone sends you a message about the health of your cat?
One line blog. I hear that they're called Twitters now.
understand you not speech mine? Electron probability mass function finding quantum receive construct indicates packet dependency allows.
"Any connection between your reality and mine is purely coincidental." -Slashdot
Hmm...so if the top 1% of income-earners pay more than a third of all income tax revenue, the top 5% pay over half, and the top 10% pay nearly two-thirds, how do you arrive at the conclusion that "only the little people pay taxes?"
(Source: http://www.atr.org/talkingpoints/012202tp-2.htm)
20 January 2017: the End of an Error.
Hmmm, your encrypted data does not look statistically random to me :-) Try this instead ...
y 3K KqtXZb3ljA/oM98PLKjfAhfRqbo1JqO4UUYUu25djiS7Ove45l pmoaSycP8T+usdqcJFtNwUrTelCNEUe9dJPbXGuGgR7JjzA9Xx 6dzu76z3XH/rf51Tx1iM8bI7EcT1ijfWt8s59J/JZpHbxJ1Vxa PHYchy
qANQR1DBwE4DmBod8oWMnB5+t0opVD15zJPHNvLYF1MxaUO
xkcd is not in the sudoers file. This incident will be reported.
Well that's pretty fast for the swiss...
It might not be useful to you. But can you speak for the needs of everyone in the world out there who needs to send information securely?
-- SIGFPE
If I may cut and paste a bit o' text:
"Los Alamos quantum cryptography uses photons randomly polarized to states representing ones and zeroes. Polarization refers to the direction of oscillation for the electromagnetic wave of a photon. These polarized photons are transmitted between sender and receiver to create a random string of numbers known only to the sender and receiver. This string of numbers becomes a quantum cryptographic key that locks or unlocks the encrypted messages that are sent via normal communication channels. Because the photons cannot be intercepted without tipping off the receiver, the quantum cryptographic key is secure and the data is secure."
So, what is the crux of the security... "Photons cannot be intercepted without tipping off the receiver..."
Really? So man in the middle cannot happen; let's just accept that on blind faith, and quantum cryptography will work. Now, never really believing in blind faith, lets think about how we can be man in the middle without tipping off the receiver, or how about who cares if we do. Don't think about the theory; its not as important as the application.
I drop fibre between A and B for key generation. I turn the magic switch and let the no key sync take place. WTH I just noticed my data is bad. A and B reset. How do I know I am still directly communicating? I jump through a bunch of hoops to make sure my twin is who I think it is and not some doppleganger... now the security is in your authentication/restart procedure, not the theory.
/\/\icro/\/\uncher
The 60 bits/second is only used for the key exchange. The key is for a ordinary symmetric cipher, such as RC5, DES, AES, or Blowfish. For example a 64 bit key for RC5 would take slightly over a second to transfer. And our friends at distributed.net have been working on breaking a 64 bit RC5 messages for the past four years and still have not exahausted the keyspace. Symmetric ciphers have many more valid keys per bitsize than asymmetic ciphers, giving you stonger protection. Keys for symmetric ciphers don't need to be as large as those for asymmetric cipers, 60 bits/second is a little slow, but definitely adequate.
Redirection isn't a problem either; to redirect the stream you'd have to observe it, and by observing it you will change it, and make it impossible to view the messages.
I guess you could always kill the recipient and read his messages, but any form of cryptography short of biometric (and others have pointed out the flaws in that) will be vulnerable to that attack.
Because I found your comment amusing. The only problem with the 71 and 3/4 minutes of silence is that before long people will clamouring for those CDS. What is preferable, N'sync or 72 mins of silence?
I mean interception, not man-in-the-middle. I cut your fiber and read your photons, without trying to pass them on to the intended recipient. Then, when you try to contact the recipient over some "conventional" channel for phase two (comparing the polarities on the two ends), I intercept that, and we discuss the polarities I intercepted. You require that my messages be signed by the intended recipient, of course, but I've broken RSA, so no problem. Then, you send the message xor'ed with the random bits, and I intercept that. I've stolen the message, and you're none the wiser.
The evaluation of an action as 'practical' . . . depends on what it is that one wishes to practice.
Here is an article in Information Security magazine explaining how quantum cryptography works and why it is significant:
1 /f eatures_crypto.shtml
http://www.infosecuritymag.com/articles/august0
"Don't touch anything."
The Law of Falling Bodies
Because he is parroting leftist "ideas" using the interesting vehicle of quoting from a convicted, wealthy, tax evader. From one example he supports his whole "theory."
/.ers percieve as truth, since everything with a valid point was modded down and his crap keeps a 2.
Gives some insight to what
Thank you for the real stats, but I am sure you will be attacked for not being specific enough, or one of the AC chickens will be pouncing on your syntax.
Eve Fairbanks says I drive a hybrid!LOL