Photons and fibre: The next generation of secure communication has arrived

by Nick Evans | Oct 19, 2018 | Articles

I’m often asked what the next big innovation in cyber-security is going to be, or what developments in the field have the most potential.

It’s a difficult question to answer because there are so many innovations taking place in many different aspects of cyber-security.
Some of the most notable include cloud technology, artificial intelligence and machine learning, all of which are set to have a significant impact on systems security.

But one that certainly piques my interest is the use of photons and fibre. Being able to incorporate data on a single photon and transport that via fibre without the prospect of being hacked is very exciting.

Firstly, for those who aren’t up on their quantum mechanics, a quick and simple definition; a photon, from the Greek word for light, is a type of elementary particle that transmits light.

Photons are unsplittable, and although they can be created and destroyed, their lifetime is infinite.

Single photons are ideally suited to sending digital information and in theory there is no limit to the amount of information they can hold.
Of course, we already use laser light beams to carry data along fibre-optic cables. But rather than spreading the data over waves of light, individual photons can do the job more securely.

The laws of quantum mechanics means that any attempt to read these photons will alter the encoding and introduce anomalies that can be detected immediately, so secrecy can be guaranteed.
The idea has been around for a while but it is only in recent years that the technology has developed to a point where concept turns into reality.

A research team at the University of Alberta was working on this back in 2011. Zubin Jacob, a professor of electrical and computing engineering, explained that working with single photons would allow much more complex information to be encoded on an individual particle of light.

“A single photon could carry encryption codes, which are far more complex than the security password information we currently use to protect sensitive data,” he said.

Jacob predicted that the technology was at least a decade away and said it would be not be aimed at general consumers.

“This technology is destined for markets such as the military that requires extremely high levels of data encryption,” he said. I think he was right on the timing for availability but failed to see the level of security now required within commercial practices.

In 2016, researchers at the University of Twente in the Netherlands succeeded in packing more than 10 bits of information into a single photon for the first time.

The team used an innovative method for detecting individual photons and created an alphabet of 9072 characters that could be used to encode information.

Professor Pepijn Pinkse, one of the researchers, said using this method there is no theoretical limit to the amount of information that can be sent, as it is determined by the size of the alphabet you create. Further, Professor Pinkse said that the main objective of the study is to raise quantum communications to a higher level.

“The more information you can transmit with photon, the more secure and the faster you can make quantum communication,” he added.
The problem, until recently, has been the transmission distance achievable; the range has been limited to a few hundred kilometres because photons can be scattered and lost from the fibre.

Then, earlier this year, computer scientists at Toshiba Research Europe’s Cambridge laboratory found a way to enhance the transmission distance.

Rather than sending single photons from one end of the fibre to the other, their breakthrough allowed light pulses to be sent from both ends of the fibre to a central location, effectively doubling the transmission distance. They said this was an important step in the commercial development of this technology.

I firmly believe that transporting data within photons via fibre is the future of secure communication. There are two reasons for this. Firstly, it will increase our capacity to transport data at speed and in volumes.

Secondly, it will negate so-called ‘man-in-the-middle’ hacking attacks. This is where communication between two systems is intercepted by an outside entity.

Hackers attempting to intercept data sent within photons via fibre would find their efforts to be in vain, as not only will the information they are trying to access self-destruct, but the hacking attack would introduce anomalies that could be detected immediately.

This would be particularly useful in defence and in finance. For example, financial institutions could use the technology to set up secure networks to connect their sites at national and even international level and use them to send highly confidential data, such as customer information. It could also be used to make absolutely secure phone calls.

China seems to be ahead of the rest of the world when it comes to implementing this technology.

It has already set up an ‘unhackable’ communications network to send secure messages between key individuals in the government, military, finance and electricity sectors, and last year launched a satellite to test quantum communication over large distances.

In the US and Europe the technology is mostly being used in research projects at the moment, but I believe it is only a matter of time before we see widescale adoption by governments, militaries and eventually financial institutions and enterprises as a whole.

Contribution by Dr Debbie Garside, As originally published in SCMagazine: