Follow Us

We use cookies to provide you with a better experience. If you continue to use this site, we'll assume you're happy with this. Alternatively, click here to find out how to manage these cookies

hide cookie message

Cambridge team in quantum crypto breakthrough

Quantum theory harnessed for video

Article comments

The rarefied field of encryption Quantum Key Distribution (QKD) has edged another step closer to real-world use.

Researchers at Toshiba's Cambridge Research Labs (TREL) have now distributed encryption keys at a rate of 1Mbit/s over an extended distance of 50Km, and done so continuously over a 24-hour period. The previous best over 50km was 256kbit/s, but the main advance is the ability to run the system without the need for manual tinkering.

It sounds extremely abstract for a technology that as yet has no commercial application, but the milestone is important, the lab said.

QKD does not improve on encryption per se but the security with which the keys - in the case of QKD these can be incredibly long - can be distributed. What it offers is a technology to distribute those keys with the certainty that any interception will be 100 percent detectible. However, because the keys are so long, the bit rate at which they can be transmitted over given distances becomes a major practical limitation, hence the obsession with speed.

The problem with the equipment needed to make QKD work is that it is easily upset by even the tiniest thermal changes in the physical medium of fibre optic glass filaments, which will stretch relative to one another by nanometres over time. The CRL team has found a way to detect and automatically adjust this movement by physically stretching these fibres to counteract the effect.

"It means the system can be used by anyone. You don't need a quantum physicist to operate it," said project head, Dr Andrew Shields.

"Although the feasibility of QKD with megabits per second has been shown in the lab, these experiments lasted only minutes or even seconds at a time and required manual adjustments. To the best of our knowledge this is the first time that continuous operation has been demonstrated at high bit rates," said Shields.

QKD combines one of the most mathematically intense fields in technology, that of encryption, with one of its most abstruse, that of quantum physics.

With the new development, QKD was now possible at high speed over long periods of time which made it a practical for applications such as video, Shields said.

Practical uses of QKD always seem to be at least three to five years off, but that partly reflects the commercial problems of making the technology affordable and getting it accepted. A big hurdle is the lack of standards, something that developers and standards bodies plan to address.

The team plan to demonstrate the system using a network set up in conjunction with the Japanese National Institute of Communications and Technology (NICT) in Tokyo, with the hope of luring military, government and possibly healthcare sectors that would have a use for it.


More from Techworld

More relevant IT news


Send to a friend

Email this article to a friend or colleague:

PLEASE NOTE: Your name is used only to let the recipient know who sent the story, and in case of transmission error. Both your name and the recipient's name and address will not be used for any other purpose.

Techworld White Papers

Choose – and Choose Wisely – the Right MSP for Your SMB

End users need a technology partner that provides transparency, enables productivity, delivers...

Download Whitepaper

10 Effective Habits of Indispensable IT Departments

It’s no secret that responsibilities are growing while budgets continue to shrink. Download this...

Download Whitepaper

Gartner Magic Quadrant for Enterprise Information Archiving

Enterprise information archiving is contributing to organisational needs for e-discovery and...

Download Whitepaper

Advancing the state of virtualised backups

Dell Software’s vRanger is a veteran of the virtualisation specific backup market. It was the...

Download Whitepaper

Techworld UK - Technology - Business

Innovation, productivity, agility and profit

Watch this on demand webinar which explores IT innovation, managed print services and business agility.

Techworld Mobile Site

Access Techworld's content on the move

Get the latest news, product reviews and downloads on your mobile device with Techworld's mobile site.

Find out more...

From Wow to How : Making mobile and cloud work for you

On demand Biztech Briefing - Learn how to effectively deliver mobile work styles and cloud services together.

Watch now...

Site Map

* *