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Using Diamonds to Create Unhackable Code
IAmTheDave writes "Researchers at Melbourne University have grown diamond particles 1/1000 of a millimetre on optical fibres which they can use to transmit single photons of light at a time. The diamonds are grown on the optical fiber by raining carbon molecules onto the tip of the fiber. They claim that by transmitting information in single photons, any interception of transmitted photons will be useless to the interceptor, and thus the message will be completely unhackable. Transmission speeds are currently slow - 120km/h, but are expected to speed up."
Jeeze.
Chas - The one, the only.
THANK GOD!!!
Stretch 3000 miles of this across the atlantic, set up a secret recieving station on the African coast, and voila! One secret, untappable method for my world takeover, I mean, world communication plan!
This is far from an "unhackable code". In fact, it's not even a code. Please stop thinking that "quantum cryptography" is a form of cryptography. It's simply an interception-resistant media.
Disconnect and self-destruct, one bullet at a time.
I'm sure I'm not the only one who immediately thought "Titanic" when I saw the headline...
So its really is true:
Diamond (encryptions) are forever!!
Buh wump dump.
(thanks. I will be here all week.)
Transmission speeds are currently slow - 120km/h, but are expected to speed up
Don't the photons travel at the speed of light in the fiber? Perhaps it is some other unit?
Wouldn't the transmission speed have to be C? I mean, C isn't constant across all mediums, but even in quartz and ruby it's significanly faster than 120km/h.
I'm left wondering how it is they've managed to slow down the transmission of a photon to 120 kilometers in one hour, presumably in the glass fiber. Usually slowing down light that much takes a great deal of infrastructure and effort, it's rarely a side-effect.
Slashdot and the www.news.com.au couldn't have both made the same screamingly stupid mistake and meant 120 kilobits per hour, right? Right?
TFA says How? What keeps a third party between the two friends from receiving the photons transmitted by one friend and retransmitting exactly the same sequence of photons to the other while keeping a record, and therefore, a copy of the message?
I'm pretty sure there's more to it than appeared in TFA, and that there is a way to be sure there isn't an eavesdropper between the two friends, but I don't know what it is.
"It is nice to know that the computer understands the problem. But I would like to understand it too." --Eugene Wigner
Right now it's downright unusable, think the kind of fiber optic you would need so 1 photon can be recieved at the other end? perfectly straight..!
120km/h, just imagine the ping!!
That technology could be "secure" assuming there is a direct link, that means no routing at all. If there is any routing involved then you just killed the concept. There is always the chance that someone will just cut the cable and "snif" it.
Not a bad idea but right now it's far from promising...
I'll stick with my encryption...
Anyone want a game of quake? We could have like 1000 pings. It'll be like old times again!
I like muppets.
Adding a repeater in the middle would add latency which could be easily detected by either end by running a few simple tests. Since this is a point-to-point technology your transmission speeds should be predictable and constant.
Not only is quantum cryptography not not a code or traditional cryptographic system, it is not exactly a perfectly "secure transmission medium" as some /.ers have suggested. It is a method of interception detection. It is a HARDWARE system that uses entanglement or the Heisenberg uncertainty principle to send photons in such a way that the communication system itself can always detect eavesdropping (and logically would cease transmission if interception is detected). It is not untapable....but any taping would do little good since it would be noticed.
------ Take away the right to say fuck and you take away the right to say fuck the government.
I hope they don't speed the connection up, I hope they're able to slow it down! Think ultimate storage medium, the only limit being the number of photons you can put in the length of a pipe.
Running out of storage space? Hello sweet superposition! Yeah, my iPod stores 4.02 * 10^18 songs, but have to listen to them all in order.
The baby's fine -- please stop sending business cards.
So these are Canadian electrons, eh ?
-- "It's not stalking if you're married!" My Wife.
Yes and no. Quantum key exchange is, as you point out, a key negotiation protocol which relies on the laws of physics to keep the negotiated key safe from eavesdroppers. However, there's absolutely no limit on the size of key you can generate. If you need a million bits of key, then fine: make a million bit key.
Once you have as many bits of key as you have bits of data, you can treat it as a one-time pad. And that would be a perfectly secure transmission, as long as both sides make sure they destroy the key once it's been used to do an encryption or decryption operation.
In other words, QKE leads quite directly to (a) a cipher and (b) a traditional cryptographic system.
IAAGSSTS (I Am A Grad Student Studying This Shit).
120 km/h to send single photon in order to establish a secure channel?
Hmm.. let me get this straight. So if I burn a DVD and send it to California from New York using FedEx 2Day service for $14.59, could I name this post as "Unhackable Transmission Medium for only $14.59"?
"Don't let fools fool you. They are the clever ones."
I really don't think this tech is going anywhere.
The problem I have with this is that it really doesn't have any place in the internet at large. Sure, it's great for point to point direct connections--ie, my secure installation has a direct diamond-fibre connection to your secure installation, but it really doesn't do much for more public transfers, like internet banking.
This will secure transmissions between banks and internally at banks, but a secure system is only as secure as it's weakest link, and this doesn't improve security on the internet.
Since the internet uses routers, switches, and hubs someone could always gain access to the router or pickup the broadcast from a hub through some other means and cause that system to log packets or duplicate them elsewhere, etc.
Or is there a way to incorporate this into a system similar to the internet as we know it and make my home connection to my bank/paypal/yahoo shopping more secure?
I am no expert in the field of quantum cryptography, but i could imagine a sort of situation where the "man in the middle" captures all of the photons, before they are sent to the receiver, then calculates the required speed to make up for the latency and boosts the "signal" to prevent the reciever from knowing anything has gone wrong. Of course, I could be totally wrong...
University of Washington
Student
It's not that the code is unhackable, it's just that hackers won't be hacking into your bank account anymore. They'll just take the diamonds.
That has to be a typo. Even in diamond the speed of light is only a little about 2.5 times slower than in a vaccum. I'm very interested if the light is going 120 km/h in the optical cable though, because that would make it possible to theoretically build a time machine by winding the cable in a cylinder, but only if it retained that speed with more light in the cable. There is also the caveat that the metric this was solved for involved an infinitely long cylinder of rotating light, so it may not apply to finite cylinders.
what sig?
sounds just like the Mercury delay line memory from the old days. Where they used sound pulses travelling in the mercury to represent presence or abscence of bits...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
Nothing is truely random.
Except for.. well, bloody everything at the quantum level. Unentangled particles store "one bit" - if you read say, the position, the velocity is truly random (within certain bounds, on a given distribution function). Entangled particle pairs store "two bits" - you can measure two velocities, a velocity and a position, or two positions - but everything else that you measure will be random (as described before)
Dear Lord: One of your creatures may be hurt tonight. Please let it be the other creature.
Details are important.
If Einstein hadn't paid attention to details, he may never have discovered America.
Alas, Ph.D. boy, you need to either spend more time studying your courses, or spend more time on your critical reading skills; at this point it's difficult to tell which.
The encryption can be broken, sure, if you know the message. The real beauty in quantum cryptography lies in the fact that intercepting the message (a man in the middle attack) is impossible due to Heisenberg's uncertainty principle.
The January 2005 Scientific American has a good article on it (the cover story, actually).
The next time you're planning on acting so pompous, you may want to check your facts first.
AC: In quantum cryptography (which isn't quite what this article is about), there aren't any data lines to monitor -- the information is transmitted by entanglement.
No, your definitions are off. "Quantum Cryptography" is the use of Heisenberg's Uncertainty principle's guarantee that the whole state of a particle cannot be measured to ensure that a message cannot be intercepted and retransmitted.
The use of quantum entanglement to communicate data has also been proposed, but this is known as Quantum Teleportation. QT, not QC.
I had this largish thing describing what I thought of this relativly cool technology and my reticence in buying into it as the "Next Big Thing(tm)" but I think I can sum it up like this:
"All your diamond are belong to us" -- lopht
I think you underestimate just how much I just dont care.
We have had one time pad ciphers for what, 70 years? When was the last time one was cracked? When some dolt in the kremlin decided to re-use their one time pads. Other than that, it has never been broken. Quantum encryption can be exactly the same - when done right it's unbreakable. Doing it right it hard, but far from impossible
I am trolling
We should all be able to hack away at something if we acquire that device learning whatever we can about it. IMO, while referring to cyphers, secure communication and cryptography we should be using "crack" as the more appropriate term. Dunno if it's too dumb to say this, but seemingyl sets terminology to the right category. The other term I could think of was "reverse-engineering-proof" though that too doesn't seem appropriate. (Just a thought.)
No Greater Friend, No Greater Enemy! (Lucius Cornelius Sulla)
When any two idiots can burn 8GB of random data onto two DVD's and send secure text messages to each other for the rest of their lives, what the hell use is a complex physically secure network like this one?
Copying data from a DVD that you've intercepted or otherwise gained access to isn't hard. Once you've done that you can not only read any new messages they send, you can decode all the old messages you've already intercepted. And they have no way of knowing you've stolen the pad.
It just relies on a perpetual motion device to power the division by zero generator.
All arguments about the workings of quantum encryption can refer to this paper. One key assumption is that you only send a single photon, not two or none. If none arives you wasted that bit-slot, but a second photon allows eavesdropping. Traditional sources generate photons according to Poisson statistics, which means that you can't accurately meter out one photon at a time. The standard fix for this is to attenuate the signal so that the average N is much less than 1 photons per measurement slot. This effectively means you only get (roughly) a photon every 1/N slots, but you still get 2 arriving together every 1/N^2 slot. The first part is both wastful, the second vulnerable.
The current paper merely how to generate single photons more reliably using diamonds as microcavities. Essentially the diamond is a tiny laser resonator on the scale of a single wavelength (1 micron), and can only support one optical mode, so any single spontaneously generated photon goes into that mode, and your output is single, narrow wavelength photon, but no doubles. In some ways this has ceased to be a "L.A.S.E.R." since the Light is not Amplified, and the Emmision of Radiation is not Stimulated, but spontaneous. Maybe I would call it Light Organized from Spontaneous Emission of Radiation, but I digress...
If you wat to look at such microcavities, see this paper
"I love his boyish charm, but I hate his childishness" - Leela
Listen, if the intended receiver is able to pick up the signal, then a man in the middle can, too!
No. Because there is no "the signal". With QC you have two signals on the fiber and you can pick up only one, thereby destoying the other.
I'm not talking about observing the bits that go down the line. I'm talking about impersonating both sides to each other. That is a man in the middle.
Yes. And that wont work.
The other way to make MitM harder is to have a big enough shared secret. You could have secret passwords, or even a secret protocol would work too. If the MitM can't guess the shared secret, then impersonation will fail.
Thats what QC is for. You can generate shared secrets of any size by QC. And the MitM wont be able to guess them, if they are large enough.
Some people have proposed a way of quantum key generation via entangled particles. But remember that getting this shared secret to each other is also subject to MitM attacks.
No! Thats exactly the point! You cant MitM a big QC transmission without notifing the sender/reciever. All the MitM can do is a DoS.
Someone can yoink those entangled particles, and throw in new ones.
Ehem - no. There are *two* things the MitM has to measure because he doesnt know which of those the sender knows about the particle. Though luck for him - his first measurement destroys the particle.
The person you're talking to can always be an impersonator. It can be really improbable, but there is always some possibility. I'm not saying you should be paranoid, but just that every communication involves a degree of trust. Quantum magic won't make that required trust go away.
This is wrong. QC is save from MitM when used with two channels - one QC channel and a public one where transmissions cant be blocked unnoticed (for example radio).
The wikipedia isnt too bad at all about this stuff: http://en.wikipedia.org/wiki/Quantum_cryptography