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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."
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...
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.
>> There is nothing unhackable.
and if it's difficult to hack the transmission media, there is probably cleartext versions of the transmission at either end.
"un-crackable" transmission will just change the point of attack...
http://request-header.info
The moral of the story is "Don't try to use your macroscopic-world intuition to understand quantum phenomena."
It's so wrong, it's not even reliably wrong, like [people who oppose you politically]; you almost don't need to know what's right, just wait for [those idiots] to spout off and do the opposite. Unlike that, your real world intuition is so wrong it's not even on the same playing field, not a matter of "true vs. false" but "true vs. blue speckled porcupines."
In conclusion, the answer is "a bathtub full of brightly colored machine tools"; understanding the question won't get you appreciably closer to understanding QM, but it's a good start and might give you a chuckle.
Wouldn't the transmission speed have to be C?
Many people don't realize that C is the speed at which an electromagnetic wave propagates, not necessarily the charge carriers themselves. The electrons in a copper wire, for instance, move pretty slowly, on the order of several seconds per millimeter.
I didn't realize that drift velocity applies to photons in a medium, but it sounds like it may.
No, it's not possible. The whole point about quantum cryptography is that the transmission method makes it physically impossible to crack data without the recipient knowing. There simply is no way to perform a "charlie" attack (charlie denoting a third user, after Alice and Bob). I've been doing research on this subject for the past two years, and met the daughter of the man (missed meeting him by an hour) who invented the principle behind the theory.
Due to financial difficulties, the light at the end of the tunnel has been turned off.
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
I think that's bull. If the man in the middle cannot read the photons before altering them, how can the intended recipient? Explain it properly.
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?
Thank you. I'm grasping the impossibility of an eavesdropping attack, but how does this solution deal with other common communication problems, like:
Denial of service.
False positive intrusions.
Reliability without retransmission.
Is the idea to use wavelengths that are not readily absorbable by common atoms? If so, how would they theoretically be generated? Does the answer lie in the manufacture of "perfect" materials (assuming that such a material could exist)? How would impurities not eventually tunnel into the fiber?
Seriously, I completely understand that this is "breaking" research, and not an "off-the-shelf" solution. It may be achievable, or not. But it would be very interesting to hear if these issues are currently considered critical or irrelevant.
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.
Light travels 3*10^8 m/s in a vaccum. Light has a thing called index of refraction, in a vacuum n=1, in water it is 1.333 and in diamond n = 2.419 (diamond is known to have one of the highest indexes, actually the highest index of common materials). Because n is so high, the velocity of light through diamond is literally 2.419 times slower then in a vacuum (the actual velocity in this case doesn't matter, but you can probably figure it out in your head). Now you're thinking, well damn that is really fast still and you are right, it is still extremely fast. Then comes into play another factor, which when dealing with electricity and current is referred to as drift velocity, not sure if there is a special term when dealing with the physics of light so I'll call it drift velocity as well and maybe someone else can correct me if I'm mistaken. When light is passing through each of these diamonds it is being refracted, as in it is not going perfectly foward, in fact it'll even go a little backwards sometimes. As a result you get a lot of back and forth bouncing around, covering tracks already covered, moving at a high velocity, but since you're going back and forth and not straight, you cover very little distance. As a result of this, they take the average velocity which is in this case referred to as the drift velocity. Drift has such a dramatic impact that it truly does take the velocity of light all the way down to something a car could outpace. They can increase the drift velocity by being careful about the shape and orientation of the diamonds, but the effect will always be there in some form or another as far as I know (maybe there are special cases that I just can't recall right now).
/. doesnt have an equation editor so no equations were mentioned (not that they were needed to get the point across). If something about this doesnt make sense just reply with a question, I'm sure me or some other /.er can answer you (regardless of the quality of /. recently, I still have hope that it can become a haven again for geeks and geek talk and a community that helps each other out rather then criticizing each other )
The physics of all this are of course much more involved and
Regards,
Steve