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Creating the First Quantum Internet (axios.com)
Scientists in Chicago are trying to create the embryo of the first quantum internet. If they succeed, the researchers will produce one, 30-mile piece of a far more secure communications system with the power of fast quantum computing. From a report: The key was the realization of an unused, 30-mile-long fiber optic link connecting three Chicago-area research institutions -- Argonne National Lab, Fermi Lab and the University of Chicago. This led to the idea to combine efforts and use the link for what they call the Chicago Quantum Exchange.
David Awschalom, an Argonne scientist and University of Chicago professor who is the project's principal investigator, tells Axios that the concept is difficult to grasp, even for experts. MIT Technology Review elaborates: The QKD approach used by Quantum Xchange works by sending an encoded message in classical bits while the keys to decode it are sent in the form of quantum bits, or qubits. These are typically photons, which travel easily along fiber-optic cables. The beauty of this approach is that any attempt to snoop on a qubit immediately destroys its delicate quantum state, wiping out the information it carries and leaving a telltale sign of an intrusion. The initial leg of the network, linking New York City to New Jersey, will allow banks and other businesses to ship information between offices in Manhattan and data centers and other locations outside the city.
However, sending quantum keys over long distances requires "trusted nodes," which are similar to repeaters that boost signals in a standard data cable. Quantum Xchange says it will have 13 of these along its full network. At nodes, keys are decrypted into classical bits and then returned to a quantum state for onward transmission. In theory, a hacker could steal them while they are briefly vulnerable.
However, sending quantum keys over long distances requires "trusted nodes," which are similar to repeaters that boost signals in a standard data cable. Quantum Xchange says it will have 13 of these along its full network. At nodes, keys are decrypted into classical bits and then returned to a quantum state for onward transmission. In theory, a hacker could steal them while they are briefly vulnerable.
In theory, a hacker could steal them while they are briefly vulnerable.
In practice, some three-letter agency or foreign power will steal them.
FTFY
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Chicago Quantum Exchange
Great. So traders will know where the market is going or where it is, but not both.
I imagine Heisenberg wouldn't like uncertainty when it comes to his principle - or dividends ...
It must have been something you assimilated. . . .
A nice 8193 bit key should be as much protection as anyone ever needs.
While Bill Gates never said that it may be true for as long as necessary. Just use some extra long key to encode the exchange of shorter length keys. Why do we need quantum key exchange?
Some drink at the fountain of knowledge. Others just gargle.
The QKD approach used by Quantum Xchange works by sending an encoded message in classical bits while the keys to decode it are sent in the form of quantum bits, or qubits. These are typically photons, which travel easily along fiber-optic cables. The beauty of this approach is that any attempt to snoop on a qubit immediately destroys its delicate quantum state, wiping out the information it carries and leaving a telltale sign of an intrusion.
Maybe if I'm a bad guy, I'm quite OK with that. That would be something like a DDOS. Maybe I don't care about trying to steal your quantum encrypted data but I want to deny your ability to transfer data that way so you will move to a method of transmission I can read.
At nodes, keys are decrypted into classical bits and then returned to a quantum state for onward transmission. In theory, a hacker could steal them while they are briefly vulnerable.
Believe me, bad people will certainly do this. One of the ways Blu Ray encryption got cracked is that the players stored the keys unprotected in memory and smart people figured out how to dump the memory to get the keys. National actors who really want access to your data will have no problems trying to attack this weak point in the chain.
The Quantum Key exchange is interesting but not really practical. The equipment is expensive and hard to set up. Further, if you are using photons you can only send one per quantum state. If you send more than one an attacker can intercept them and figure out their state.
In the easiest example Alice sends photons either polarized (up/down / side-2-side), or diagonally. Bob will then tell Alice which way his detector was set up for each received photon. For the photons his receiver was correct he know the polarity of Alice's photon. Alice and Bob then have a shared secret to use as a key. If Eve intercepts the photons she has to both read the photons and pass them on to Bob. If her detector is set up on the diagonal and Alice sends an up/down polarized photo Eve won't know the polarization and can't send the correct photon on to Bob. However if there are multiple photons, Eve can split them up and test them individually. With 8 photons Eve has a 63 in 64 chance of knowing the photons polarity and 255 out of 256 chance of fooling Bob well enough for her attack to go undetected.
For the entire thing to work either you have to send multiple photons and have them boosted or you send one and the repeaters know Alice's pattern of polarization. In the second case this pattern becomes a key that must be kept secret across every repeater. You may as well just give Bob this key.