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http://www.forbes.com/home/enterpris...05quantum.html
an interesting read...Quote:
NEW YORK - In Cambridge, Mass., not too far from the Charles River, which cuts near Harvard and M.I.T., David Pearson is attempting to build an un-hackable network.
involves quantam cryptography... may interest some people here :)
Quote:
If someone is eavesdropping, they introduce errors into the communications," Pearson says. "If that happens we just throw the keys away and start over
The basic theme of the Quantum world, if you observe - you destroy.............Quote:
The answer is quantum cryptography, which harnesses quantum physics to create encryption keys that are all but impossible to crack because they are rendered useless by simply looking at them. Data using those keys is simply resent using new keys.
To help comprehend it, consider a snooker table, with a red ball moving from one end to the other, this is the message. To intercept it, you have to launch [white] balls from the side and observe these, when one [white] collides with the message [red] it releases energy, which is detected. But the message [red] has now been knocked off its path, and will not make it to the receiver, the message is lost.
For some major league headaches, try reading up on any aspect of the quantum world.
I find the author John Gribben to give an 'easier' path through the puzzles presented.
funny "un-hackable" !
just because something is encrypted doesn't make it secure. Ceasar's shift code was cracked, 56-bit was cracked, DES was cracked, ssh was cracked, ssl was cracked, the list goes on and on..
I think what David Pearson is trying to create is an "Un-Crackable" network, not an Un-Hackable one.
You can tell I'm from old school when those two terms mean completely different things.
Personally, I think we'd make huge leaps and bounds if we can obtain a greater degree of human security, not technological security.
Humans, the social network, is our greatest security weakness.
If you thought about it for a millsecond you wouldn't have made that comment...Quote:
funny "un-hackable"
Think about this... If you view the packet it is changed... A single packet.... So encryption isn't really relevant is it? If you can crack and encryption scheme from a single packet then it really isn't an encryption scheme. The fact that encryption keys would be re-exchanged _if_ a packet was viewed it would be a sensible to attempt a keychange because you _know_ you are being watched.....
The concepts in quantum computing aren't new but they will change many things radically - for example: a password that would take 1000 years to crack by brute force would take a year or less to crack using quantum computing... Now that changes encryption schemes doesn't it?
Somebody sent me a similar article ( http://www.msnbc.msn.com/id/7394350/ ). Something to the effect of what bracket said, throughout history there has been the rivalry between cryptographers and cryptoanalysts. Ciphers began being done on paper. There was caesar's code, polyalphabetical substitutions, computer powered ciphers... quantum cryptography is just another step up. I replied to the person with this:
Man is imperfect. The code is imperfect. The cipher can be cracked. It's transitive.
I find quantum computer highly interesting and look forward to seeing the results of its positive application.
hmmm it was an intresting read however I have a question
now both ends need to know the key right? (that is the transmitter and the reciver) and im assuming there is a finite amount of keys, and if the system moves to a new key if its being evesdropped then isnt it possible for the network to run out of keys? I mean sure more could be transmitted but if someone was still evesdropping the line from what i gather the reciving end wouldnt get them and even if they did then the evesdropper would now have the key so wouldnt a second secure method of transmition be required?Quote:
If someone is eavesdropping, they introduce errors into the communications," Pearson says. "If that happens we just throw the keys away and start over
anyone who understands this topic better than me could you please clarify/correct me here, also if what im saying is correct could a second quantumly encrypted line be used aswell, so if one line gets tapped then new keys are transmitted on the second line and then the first line switchs over to the newly transmitted keys?
also if there wasnt another way (which im sure the probably is) would it be possible to DOS a network by just evesdropping it untill it ran out of keys?
My issue of Scientific American, Cover story for Jan 2005, page 79:
Best-Kept Secrets
Unbreakable Quantum Encryption has arrived.
[An excerpt]
At the IBM Thomas J. Watson Research Laboratory, Charles Bennett is known as a brilliant theoretician--one of the fathers of the emerging field of quantum computing. Like many theorists, he has not logged much experience in the laboratory. His absentmindedness in relation to the physical world once transformed the color of a teapot from green to red when he left it on a double boiler too long. But in 1989 Bennett and colleagues John A. Smolin and Gilles Brassard cast caution aside and undertook a groundbreaking experiment that would demonstrate a new cryptography based on the principles of quantum mechanics.
The team put together an experiment in which photons moved down a 30-centimeter channel in a light-tight box called "Aunt Martha's coffin." The direction in which the photons oscillated, their polarization, represented the 0s or 1s of a series of quantum bits, or qubits. The qubits constituted a cryptographic "key" that could be used to encrypt or decipher a message. What kept the key from prying eavesdroppers was Heisenberg's uncertainty principle--a foundation of quantum physics that dictates that the measurement of one property in a quantum state will perturb another. In a quantum cryptographic system, any interloper tapping into the stream of photons will alter them in a way that is detectable to the sender and the receiver. In principle, the technique provides the makings of an unbreakable cryptographic key.
They go on to describe the generic process, talk about Quantum computers, and end with short discussion on vulnerabilities.
Side Note on David Pearson article:
I just LOVE it!!Quote:
"If someone is eavesdropping, they introduce errors into the communications," Pearson says. "If that happens we just throw the keys away and start over."
What a great idea for an encryption process that is so high tech, so secretive, so advanced that it's still vulnerable to a old Denial of Service attack by a snooper literally doing nothing but just being there.
Simply sniff the communications channel, looking for nothing and storing nothing in particular (just be there) and the keys keep getting thrown away so the REAL communications never happen.
Gotta love technology.
:D
Ahh... Theoretical Physics, my favorite. Actually, we're talking a lot faster than that! With Quantum computation a simple problem could be solved in seconds, that same problem would take the worlds current fastest supercomputer clusters billions of years to solve. My cousin who's in his ninth year of college has been in the nanolabs manipulating the spin of an individual electron inside a quantum dot, which would make a great candidate for quantum information processing because of its rather long coherence time.Quote:
Originally posted here by Tiger Shark The concepts in quantum computing aren't new but they will change many things radically - for example: a password that would take 1000 years to crack by brute force would take a year or less to crack using quantum computing... Now that changes encryption schemes doesn't it?
Soon we shall see.... Ettercap, Quantum Edition.... with photon injection....
Offense will catch up to defense.
That's how the game is played.
And it's not unhackable. It just has to be hacked in a different way at the moment
Agreed d0ppy, I believe it is better to be a skeptic than to attempt to defend a system that has not yet been fully exposed to appropriate analysis, whatever that may be. Granted, I am a layman when it comes to quantum physics (which I would guess everyone else here is as well), yet I see this as a challenge instead of a end-all solution. Exciting as this is, I feel more secure assuming that this system has exploitable flaws than assuming it can never be hacked. The denial of service idea preventing communication was really funny, yet hopefully that wouldn't be a problem. All in all, very exciting prospect and thanks for finding the article.
Ditto. I've been hinting at that over the last few threads on Quantum Key Distribution I've been in on AO, though nobody seemed to get my point.Quote:
...
Simply sniff the communications channel, looking for nothing and storing nothing in particular (just be there) and the keys keep getting thrown away so the REAL communications never happen.
...
Another thing that is important to note is that the whole point of this network is to (securely) distribute increasingly larger keys for standard encryption processes. The threat of a quantum computers searching huge keyspaces quickly has prompted a shift to prepare current networks to handle larger key-sizes that exponentally increase the keyspace. A quantum key distribution network looks to be quite secure, but soon bandwidth may need some work to represent larger keys that are more future-resistant against the possibility of a working & powerful quantum computer or some breakthrough in factoring.
This network has nothing to do with a new methodogy for encryption. It just gets larger keys from point A to point B reliably and securely, and is even supposed to allow you to notice when someone tries to intercept your network communications. (Although that last bit has me worried...with supposedly no redundancy, how can you possible error check? This looks like one part of the process that seems to contradict itself, though I may just not understand how the network actually operates, etc...)
Basically the larger the key, the more secure you theoretically are because there will eventually be a point where a given itteration of quantum computers couldn't search the entire keyspace fast enough (2^999999999999999 keyspace/key-size anyone? Up to 303,030,303,030,303 digits long, takes up 113.68TB of disk-space per key, 24,770 4.7gb DVDs...how is that for "takes a long time"?), so that it would be considered "secure", or at least more secure.
Well, after throwing out (and working out) that huge number in the example, I should probably dip into what a quantum key distribution network should solve. It should quite simply allow you to secretly transport your huge keys, and know when someone got ahold of a copy of them so you can generate a new key. (Although if you ended up missing 24,770 DVDs, I'd hope you might realize that key could be compromised and you'd better not encrypt your data with that key set) The key exchange is supposedly worked out before hand, so that once the two nodes have agreed on a key, the information will be encrypted with that key and then sent over public channels...
<fragment>I've also been researching into Man-in-the-Middle attacks and how they would have to operate to play a Quantum network. Conventional encryption/authentication schemes and not some new fabled quantum-crypto stuff, actually make it somewhat difficult to do a man-in-the-middle attact. Mainly since as the man in the middle, you must make sure to negotiate keys to something you can decrypt and encrypt between parties, but also make sure that Alice and Bob don't somehow know / figure out what each other's key *should* be through their communications and eventually realize that there is a man in the middle logging everything and re-encrypting it on the route from Bob to Alice, etc. Either way this process should be difficult given how there are two seperate channels to monitor (public internet & the quantum key distribution network) and that Alice might actually meet Bob in person (or perhaps even the man in the middle meets Alice/Bob) to exchange the keys. If it goes wrong, Alice or Bob may realize the negotiation isn't what it should be, etc., and then refuse to send the key...</fragment>
A foolish idea that popped up in my head and could possibly be very inpractile.
I think that using quantum entanglement you could change the state of one atom by changing the state of a second atom.
I have no idea how distance affects this. But if distance does not matter much, there you have the most secure channel ever.
I will need to read a hell of a lot more on this subject..
but even if 50% of photons are twins.. you still only get half the messageQuote:
When two photons are created, there exists the potential for an opening to an eavesdropper. If a hacker can intercept just one photon key they have enough information to decrypt one bit of a message. "We don't like it when we get two photons," Yeh says.
Here is a point I was going to make.. Distance..Joins, Repeaters..
Hmmm gravity neutrinos, radiation? magnetic fields.. (I will read on)Quote:
In addition, using single photons to build encryption keys has one fundamental drawback: distance. Optical networks need repeaters--which strengthen and advance signals--every 100 kilometers to keep their signals strong over long distances. But like the theoretical eavesdropper, a repeater has to observe the photon in order to amplify it and send it on, thereby ruining the key.
But these things will affect a beam of photons..
Schneier isn't a fan of quantum crypto
http://www.schneier.com/crypto-gram-0312.html#6
It's always the people that are the problem and they still have to be at either end using the system.Quote:
Quantum Cryptography
MagiQ Technologies is now selling an actual product that uses single photons to exchange keys over fiber optic lines. Navajo systems use photons to transmit encryption keys over fiber-optic lines, and the security is based on the quantum law that an observer--an eavesdropper in this case--perturbs the system by observing it.
This isn't new. The basic science was developed in the early 1980s, and there have been steady advances in engineering since then. I describe how it all works--basically--in Applied Cryptography, 2nd Edition (pages 554-557).
I don't have any hope for this sort of product. I don't have any hope for the commercialization of quantum cryptography in general; I don't believe it solves any security problem that needs solving. I don't believe that it's worth paying for, and I can't imagine anyone but a few technophiles buying and deploying it.
It's not that quantum cryptography might be insecure; it's that we don't need cryptography to be any more secure.
Security is a chain; it's as strong as the weakest link. Mathematical cryptography, as bad as it sometimes is, is the strongest link in most security chains. The computer security, the network security, the people security--these are all much worse.
Cryptography is the one area of security that we can get right. We know how to make that link strong. Maybe quantum cryptography can make that link stronger, but why would anyone bother? There are far more serious security problems to worry about, and it makes much more sense to spend money securing those.
It's like defending yourself against an approaching attacker by putting a huge stake in the ground. It's useless to argue about whether the stake should be fifty feet tall or a hundred feet tall, because the attacker is going to go around it. Even quantum cryptography doesn't "solve" all of cryptography: the keys are exchanged with photons, but a conventional mathematical algorithm takes over for the actual encryption.
I'm always in favor of security research, and I have enjoyed following the developments in quantum cryptography. But as a product, it has no future.
My take is that you get the message duplicated / cloned ?Quote:
but even if 50% of photons are twins.. you still only get half the message
There is, in the quantum world, wherein distance is NOT an issue, where something that happens here, can have an instantaneous effect ANYWHERE in the universe ..................Quote:
Here is a point I was going to make.. Distance..Joins, Repeaters..
Schrodinger's cat is the basis :
Where Schrodinger whilst attempting to show the absurdity of the quantum theory, devised an experiment.
A cat is sealed into a container, in there is a phial of poison, and the trigger is a lump of radio-active material, it is possible to set up the experiment so that there is a 50-50 chance that ONE of the atoms will decay in a set time, and emit an electron, which would release the poison and kill the cat.
But, until it is OBSERVED, the cat is neither dead nor alive, but exists in both states at once.
Now, if you take a second cat / container / et al.
Now, ONE cat WILL be dead, and ONE will live.
The instant that you open one container to check on the cat, at that instant the fate of the other cat is known, and the distance to the other cat was irrelevant.
This is [obviously] just a rough hash of what I've perused in my reading.
Please don't ask for details, as the details just get weirder :)
In the crypto world it might not SEEm as thought there is any connection, but when it comes to Quantum; ANYTHING can happen..........
After that little lecture,
Beam me up Scotty!
Its imposible to create an un crackable network because there is always the human element nothing that is done by a human is ever perfect only god can create something that is truly perfect. There will always be a student to show up the master so to speak. someone will write done a password or put it on their pda of something then some one will hack the pda and get the pass and their in. and dont even think of neging me for being stupid cuz im not if the pda belongs to someone with access to the system then the pda becomes a part of the system and it can be hacked