Scientists make Internet unhackable using quantum cryptography

Researchers at Toshiba have come up with a way to create unhackable networks using quantum mechanics, it was revealed today.

Scientists at Toshiba's European research laboratory at Cambridge University have found a technique that is close to perfecting security on the Internet.

Quantum cryptography generates a series of uncrackable codes that encrypt data in a way that reveals whether it has been eavesdropped on or tampered with by hackers. The technique, dubbed "quantum key distribution" and outlined in the journal Physical Review X, has until now been costly and limited because it requires a separate dedicated optical fibre to carry data.

But the Toshiba research team has found a way around that that involves sending data along normal optical links and using a detector that can sense when the line is being hacked or interfered with.

"The requirement of separate fibers has greatly restricted the applications of quantum cryptography in the past, as unused fibers are not always available for sending the single photons, and even when they are, can be prohibitively expensive," said Andrew Shields from Toshiba Research in Cambridge.

So far QKD has been used by a limited crop of security firms like ID Quantique in Switzerland and US MagiQ. It is hoped the technology will be adopted for business and home networks.

"QKD isn't so expensive, probably comparable to a high-grade firewall - in the range of tens of thousands of pounds. So certainly in a corporate environment it's already affordable, and as time goes on I'm sure we'll see the technology get cheaper and cheaper," said Shields.

However, telecoms firm BT is not convinced that this technology is either necessary or useful.

"This is of academic interest only," Bruce Schneier, chief security technology officer at BT, told the BBC.

Referring to a 2008 article he wrote for Wired, Schneier argued that the security of codes is not the biggest concern when it comes to hacking.

"It's like defending yourself against an approaching attacker by putting a huge stake in the ground - it's useless to argue about whether the stake should be 50 feet tall or 100 feet tall, because either way, the attacker is going to go around it," he said.

Researcher Zhiliang Yuan, who worked on the project, told Reuters that the team planned to carry out field tests on the system but he predicted it could be rolled out commercially within a few years.