Quantum Cryptographic Networking?

May 20th, 2009 by · 2 Comments

Metro fiber specialist abvt and security/defense consultant QinetiQ have announced that they will work together to advance network based quantum cryptography.  Quantum cryptography relies on a principle of quantum physics which says that if you measure something you change it.  In terms of use in communications, the dream of quantum cryptography is that you can't eavesdrop without being detected - via any method.  If you're not a physicist, it's obscure and counter-intuitive, and really cool (at least for me).  Add it to fiber networking, and what you have is the ability to build a link that is completely and totally secure.

Now, for most applications, this is actually not terribly useful.  That's because modern cryptography is already darn good, it simply isn't the weak link.  Hackers don't spend time breaking decryption algorithms, only researchers do that.  Hackers spend time taking advantage of human error - either by programmers or by users - because humans make so many of them.  But governments love this sort of thing, since they like to think they have the people side of security licked.  Well also because they may have (or simply dream of having) the stockpiled resources to attack encrypted streams directly, so they fear others have or seek the same capability.

Why Abovenet?  Well for one thing, the work is going on in London where Abovenet has a dense network.  And for another, when it comes to quantum cryptographic networks, we are still talking about slow speeds over metro distances.  Only recently researchers managed to achieve 10Mbps over a distance of 20km, which was a huge leap from 10kbps.  So we aren't talking about a secure telepresence hotline between Washington and Moscow here.  More like a single video feed across town over a metro ring.  I don't quite understand where the speed and distance limitations come from, but obviously they are working on it.  Other than that, I don't know what Abovenet gets out of this except a relationship with a defense contractor and some good PR - but maybe that's plenty.


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Categories: Internet Traffic · Metro fiber

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2 Comments So Far


  • Dan Caruso says:

    Quantum physics is a hobby of mine. Sick, huh? The physics behind Quantum Cryptographic are truly mind-boggling. You might recall my post on Quantum Teleportation. Another application is Quantum Computing. Since the abacus, computer science has not changed. It is all about ones and zeros. However, quantum computing will enable a whole new computer science–one that will take a generation or two of human to grasp. It is not about 1’s and 0’s, it is about “qubits” (short for quantum bits) which take on the states of 1s and 0s and in between all at the same time.

    Entanglement is the physical phenomenon. It is not theory. It is experimentally demonstrated.

    Quantum Cryptographic is not simply a more advanced way of encrypting. Since the day’s of Julius Ceasar’s cyphers, encryption has been about hard to break codes or math problems. Today’s encryption only works because of how hard math problems are to solve–and we don’t have powerful enough computers to solve them. Quantum Computer ironically will be able to solve these math problems with ease, making all of today’s encryption immediately obsolete. But Quantum Encryption will be one step ahead–by not relying on passing along an encrypted code. Instead, entanglement is used to sidestep the need to “communicate” the full message.

    Interest, huh?

  • Interesting post Rob as well as comment by Dan. I’d also like to share what I know about Quantum Cryptographic Networking:

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