>Can you use the same fibre for this quantum secure 60bps channel for your standard traffic too, or would they interfere
They would dramatically interfere, the scattered light from the "normal" channal would blind the single-photon detectors of the "quantum" channel. Quantum cryptography will therefore remain expensive for a long time, since you really need a specific direct point to point connection.
>Wasn't that the same place that managed to transfer information faster than the speed of light using a quantum pair a while back?
Yes and No : they never managed to transfer information faster than light, because it's impossible, but they made experimental tests of EPR correlations, which ivolves "faster than light" correlations in quantum pairs.
In fact, this swiss team is the leading (civil?) team in the world for practical cryptography through fiber. It was also the first one to use the fiber of an actual telecomunication network, is the first one to actually sell something, and to do it over such a long distance (67 km)
Disclaimer: I work in the field of quatum cryptography (but not in Gisin's team)
>meaning that any disruption of your connection for more than a few seconds causes you to completely distrust that fiber.
No, and that is, the keypoint of QC : you suppose that a spy is actually tapping the fiber, trying to get as much information as physically possible. But you can measure the disturbance during the transmission, hence deduce how much information a perfect spy could have. After that, you can use mathematical techniques ("privacy amplification") to be sure the dpy doesn't know anything useful.
In short: QC allows you to know wether a spy is here or not, and how good this spy can be, and you do NOT have to trust your fiber.
Disclaimer : I work in the field of quantum cryptography and my opinions about it can be biased
>Gov't jobs don't really add anything to the economy, though.
It's definitly not the case when we're dealing with open source. I often consider the Open Source movement being a world wide decentralized public service: volunteers, universities and private companies release their work to everyone else. If German governement pays engineers to work on Linux, their work would be useful for a lot of other people, and not only in germany, since it's open source.
That is a net benefit for the economy.
It seems NSA needs a "security enhanced" OS for its own website. If you look at
the statistic of their website
on netcraft , it seems that they have to reboot their solaris servers every 3 days !
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>Can you use the same fibre for this quantum secure 60bps channel for your standard traffic too, or would they interfere They would dramatically interfere, the scattered light from the "normal" channal would blind the single-photon detectors of the "quantum" channel. Quantum cryptography will therefore remain expensive for a long time, since you really need a specific direct point to point connection.
>Wasn't that the same place that managed to transfer information faster than the speed of light using a quantum pair a while back? Yes and No : they never managed to transfer information faster than light, because it's impossible, but they made experimental tests of EPR correlations, which ivolves "faster than light" correlations in quantum pairs.
In fact, this swiss team is the leading (civil?) team in the world for practical cryptography through fiber. It was also the first one to use the fiber of an actual telecomunication network, is the first one to actually sell something, and to do it over such a long distance (67 km) Disclaimer: I work in the field of quatum cryptography (but not in Gisin's team)
>meaning that any disruption of your connection for more than a few seconds causes you to completely distrust that fiber. No, and that is, the keypoint of QC : you suppose that a spy is actually tapping the fiber, trying to get as much information as physically possible. But you can measure the disturbance during the transmission, hence deduce how much information a perfect spy could have. After that, you can use mathematical techniques ("privacy amplification") to be sure the dpy doesn't know anything useful. In short: QC allows you to know wether a spy is here or not, and how good this spy can be, and you do NOT have to trust your fiber. Disclaimer : I work in the field of quantum cryptography and my opinions about it can be biased
>Gov't jobs don't really add anything to the economy, though. It's definitly not the case when we're dealing with open source. I often consider the Open Source movement being a world wide decentralized public service: volunteers, universities and private companies release their work to everyone else. If German governement pays engineers to work on Linux, their work would be useful for a lot of other people, and not only in germany, since it's open source. That is a net benefit for the economy.
It seems NSA needs a "security enhanced" OS for its own website. If you look at the statistic of their website on netcraft , it seems that they have to reboot their solaris servers every 3 days !