Quantum Cryptography Protects Network

Researchers have demonstrated the use of "unbreakable" quantum cryptography to protect a standard fiber optic network.

For years, researchers, pundits, and privacy advocates have been hailing quantum cryptography as the best technology for protecting data and network links, but the technology has always been so far off in the future that few people have paid much attention to it. That may all be changing, since the Integrated EU-Project SECOQC (Development Network for Secure Communication Based on Quantum Cryptography) group, led by the Austrian Research Centers, have successfully demonstrated the use of quantum cryptography to secure a standard commercial fiber optic network. The network connects six locations in and around Vienna, Austria, and uses about 200 km of commercial fiber.

Traditional cryptography uses mathematical techniques to encrypt and protect data; in theory, all those ciphers can be undone with enough time and computing power…and there’s always the danger some unforeseen flaw in the mathematics may made decrypting the information much easier than anticipated. However, quantum cryptography, first developed by IBM’s Charles Bennet and Montreal University’s Gilles Brassard more than two decades ago, is effectively tamper-proof. In a nutshell, it takes advantage of Heisenberg’s Uncertainty Principle, which states that quantum information cannot be measured without altering it. The quantum cryptography technology can instantly determine if the quantum bits in a data feed have been disturbed. In this case, the technology has been applied to photons racing across the protected fiber optic network: it detects photons in the data stream and generates a numerical key describing the data. If the key does not match the same key generated on the receiving end, users know the data has been observed in transit.

In the demonstration, researchers shows that the network, like traditional IP networks, can automatically re-route data to other nodes, bypassing compromised links so users can remain in secure contact even if a portion of the network is compromised.

The project has been underway for four and a half years, and researchers hope the successful demonstration will page the way for organizations like businesses, government agencies, financial institutions, and other organizations to look into quantum cryptography to secure their key network links.

[Images courtesy of Austrian Research Centers.]