Quantum Cryptography

Seen in Jon Erickson’s Blog and on Science Daily – Northwestern University and BBN Technologies have collaborated to demonstrate a truly quantum cryptographic data network.

By integrating quantum noise protected data encryption (quantum data encryption or QDE for short) with Quantum Key Distribution (QKD), the researchers have developed a complete data communication system with extraordinary resilience to eavesdropping.
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This QDE method, called AlphaEta, makes use of the inherent and irreducible quantum noise in laser light to enhance the security of the system and makes eavesdropping much more difficult. Unlike most other physical encryption methods, AlphaEta maintains performance on par with traditional optical communications links and is compatible with standard fiber optical networks.

As soon as quantum computing moves out of the theoretical and into the practical, most cryptography we use today will become useless. (With a big enough quantum computer, you could theoretically try all possible keys in linear time, rather than tediously brute-forcing in exponential time.)

Fortunately, quantum cryptography is also making great advances, so we’ll have something to move to!