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Domain: idquantique.com
Stories and comments across the archive that link to idquantique.com.
Stories · 3
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Commercial Quantum Cryptography System Hacked
KentuckyFC writes "Any proof that quantum cryptography is perfect relies on idealized assumptions that don't always hold true in the real world. One such assumption is related to the types of errors that creep into quantum messages. Alice and Bob always keep a careful eye on the level of errors in their messages because they know that Eve will introduce errors if she intercepts and reads any of the quantum bits in a message. So a high error rate is a sign that the message is being overheard. But it is impossible to get rid of errors entirely, so Alice and Bob have to tolerate a small level of error. This level is well known. Various proofs show that if the quantum bit error rate is less than 20 percent, then the message is secure. However, these proofs assume that the errors are the result of noise from the environment. Now, physicists have come up with an attack based on the realization that Alice also introduces errors when she prepares the required quantum states to send to Bob. This extra noise allows Eve to intercept some of the quantum bits, read them and then send them on, in a way that raises the error rate to only 19.7 percent. In this kind of 'intercept and resend attack,' the error rate stays below the 20 percent threshold and Alice and Bob are none the wiser, happily exchanging keys while Eve listens in unchallenged. The physicists say they have successfully used their hack on a commercial quantum cryptography system from the Geneva-based startup ID Quantique." -
How To Build a Quantum Eavesdropper
KentuckyFC writes "Quantum encryption is perfectly secure, in theory. In practice, however, there are loopholes. Now Japanese scientists have designed a quantum eavesdropper that exploits one of these loopholes to listen in to quantum conversations. QC's security arises from the impossibility of making a perfect copy of a quantum object without destroying it — so the sender and receiver can always tell if they've been overheard. But it turns out that an eavesdropper can make imperfect copies and use them to extract information from a quantum message without alerting sender or receiver (abstract). The Japanese design does just this. That should worry banks and government agencies that have begun to use some of the commercial quantum encryption systems now available." -
Quantum Cryptography Leaving the Lab
Theodore Logan writes "More than a year ago, MagiQ announced the world's first commercial quantum cryptography system (pdf), with ID Quantique following closely in their footsteps. Currently, the technology is limited to offering point-to-point connections up to a maximum distance of around 50 km, but this is likely to be greatly improved on in coming years. The systems available today are prohibitely expensive for the average Joe (MagiQ's are priced at more than $50,000 per unit), but one could envision a future in which they are built into the infrastructure by non-end user actors. Does this spell the end of the field of cryptography? Will systems like this ever become commonplace, or will they be reserved for sensitive financial transactions and military applications? What impact will quantum cryptography have on society? Good articles available from International Herald Tribune, EE Times and CNET."