Future Tech: Seeing the Light

Sept. 10, 2015
Light-Enabled Wi-Fi may be the future of secure communications technology

Any dealer with customers using Wi-Fi has been asked about the security of Wi-Fi technology. Radio waves have a pesky habit of going through walls and leaking into neighboring buildings or out into public places — the concern is real.

As a solution for this fear, a new technology is being developed at the University of Edinburgh in Scotland. Called “Li-Fi” — short for Light-Enabled Wi-Fi — it was first developed by Professor Harald Haas, the University’s chair of mobile communication. The technology, he says, offers faster, safer transfer of data than conventional Wi-Fi.

How it Works

Visible Light Communication (VLC) is the use of light to transmit data wirelessly. Li-Fi refers specifically to technology that is high-speed, bi-directional and networked. As a bonus, because it does not rely on the radio spectrum, Li-Fi provides 10,000 times more, and free, bandwidth — the fundamental resource of all communication systems. There is a radio spectrum squeeze in just about every developed country in every existing bandwidth. Li-Fi offers an alternative.

However, it is the security aspect that might give it its first boost. Haas says Li-Fi offers greater security than Wi-Fi. “Light waves do not pass through walls, so secure wireless communication is possible in cyber-secure spaces,” Haas explains. “Moreover, there are areas where radio simply does not work, or is not permitted such as underwater and in aircraft cabins. The possibilities are nearly unlimited.

“In five years, we will see Li-Fi modules that are the size of a quarter coin,” Haas predicts. “The price will be sub-$10.” He expects such modules to be integrated in most LED lamps.

“We will see 25 percent of all indoor wireless traffic carried by the lighting system. You will see many new lighting companies, and some of the existing ones will be gone — similar to what we have witnessed when digital photography eliminated analog photography,” Haas says.

Haas’s high-speed bi-directional wireless technology using light was demonstrated this past fall in New York City. Haas hopes to commercialize the technology through a spin-off company called pureLiFi.

Security Benefits

Not only can Li-Fi send information securely, it holds the possibility of sending data at far greater speeds than conventional Wi-Fi — data that could be tied to an existing security system. Haas notes that improved user security increases the productivity and profitability of organizations by minimizing the opportunity cost of information leaks, and addresses the weakest element in the security chain — the human aspect.

“Typical RF (radio frequency) solutions are avoided in many industries due to the penetrative and wide-spread nature of their coverage areas,” Haas says. “This provides possible access outside of the physical limitations of the intended user, compromising the security of the network. Therefore, the ability to monitor users and their actions in real-time becomes extremely limited.”

As contrasted to RF communications, there are several benefits to the use of visible light for communication. These result mainly from the inherent properties of light, which is quite directional — as opposed to the omni-directional spreading characteristic of RF — and therefore, controllable. Haas lists the following benefits:

  • Security: Provides entirely secure access. Where there is no light, there is no data.
  • Safety: Does not produce electromagnetic radiation and does not interfere with existing electronic systems.
  • Localization: Allows localization due to the small coverage area of Li-Fi access points; localization can also be used for very precise asset tracking.
  • Data density: Provides ubiquitous, high-speed wireless access that offers greater data density (data rate per unit area) than RF through high bandwidth reuse.

In a networked scenario, Li-Fi provides a possible solution to securing wireless access. Li-Fi uses visible light for communications. Visible light, including near-infrared wavelengths, cannot penetrate opaque objects, which means that the wireless signal is constrained to within a strictly defined area of illumination.

In addition to proprietary hardware requirements before anyone can access the system, the defined illumination area allows precise partitioning of any environment. As a result, Haas says, there are multiple distinct aspects improved within an organization.

For starters, every user can be mobile by using a dedicated desktop unit (DU) as a token. The number of possible active users can be strictly monitored and controlled since every user requires a DU to access the network.

It is not possible for any one employee to “hear” information sent to the server/network by another employee, since the uplink communication is on an entirely difference frequency from the downlink. Every file can have a simultaneous “dual-gate locking” system. One gate is unlocked with the traditional username and password combination, while the other is unlocked based on the specific location of the device that is requesting access to the file, i.e., the specific access point (AP) and user device combination that is requesting access. In this manner, the attack surface of the network is significantly reduced.

File access is permitted only if a device is connected to the Li-Fi network. Once a user connects to the Li-Fi network, they can download and modify certain files on their machine; however, the files that are downloaded are hardware encrypted with software monitoring the connection to the network. So any file access will require the users to be connected to the Li-Fi network, minimizing the vulnerability of the organization.

Data Tracking for RMR

Every device that can connect to the network can be localized and tracked using the technology. This allows implementation of geo-fencing — where the movement and connection of every device can be monitored, Haas explains. Access to various Li-Fi APs in the network can be preconditioned on activating a specific set of Li-Fi APs en-route. After registering with and being handed over to a neighbouring Li-Fi AP, the user is permitted to connect to the next neighbor.

Traditionally, a secure location will permit access to anyone with the appropriate authentication, Haas says. In a Li-Fi system, the network access moves with the relevant individual (as described above), and thus an attacker could gain access to the network with a user’s credentials only in the presence of the user. Instead of securing a specific location, the organization can now secure only the relevant users and their path.

As a result, a security integrator can provide the customer with enhanced predictive statistical models for user behavior based on monitoring the network activity of the users, as well as the movement patterns of the employees that are using them, similar to the way banks monitor client transactions, Haas says.

Likely Applications and RMR Opportunities

The range of possibilities for light-enabled networking is as wide as a lightbeam is narrow. One healthcare application that promises great RMR potential might see a micro-LED integrated into an earring, for example. That LED would monitor temperature, blood pressure or sugar levels in the user and transmit the data to a central station — the same one that monitors entry access or alarm status.

In a world abuzz with The Internet of Things (IoT), Li-Fi creates the possibility of everyday objects that house LED lights being able to transmit data. In many cases, vehicles, household appliances, even jewelry already have LEDs. Li-Fi offers opportunities across sectors including mobile communications, energy, healthcare, transport, manufacturing, lighting, security and advertising. The industry is estimated to be worth at least $6 billion in the next five years.

In hazardous environments where radio signals are not permitted, such as offshore oil and gas platforms, using light waves to send data wirelessly could save the industry hundreds of millions of dollars a year in maintenance cost and greatly enhance safety — and give integrators another sales opportunity.

Benefits Beyond Security

There are benefits beyond the security business. As increasing amounts of internet data are transmitted through mobile networks, the current radio spectrum could run out of capacity in the next five years. This looming spectrum crunch would severely limit people’s ability to access information — potentially costing the world’s economy billions of dollars. Li-Fi is a non-RF alternative.

“The UK industry regulator for communications, Ofcom, has warned that the available radio spectrum will run out by 2020. By that time, it is forecast that there will be a staggering 7 trillion wireless devices in use. This means for every person on the planet, there will be 1,000 wireless devices, so a solution is needed,” Haas says, noting that the situation is similar in the United States.

Li-Fi also gives much higher transmission speeds and capacity. By using a LED light bulb, data can travel at more than 10 gigabits per second. With multiple light bulbs in an office or factory space, there would be hundreds of gigabits per second throughput available.

With conventional Wi-Fi, the same room can only have a single Wi-Fi access point, as the radio signals from additional access points interfere with each other, compromising transmission capacity. The latest Wi-Fi technology, WiGig, can transmit up to 7 gigabits per second, but in a Li-Fi-enabled room, the total capacity could be increased significantly, easing the bandwidth crunch.

The operational distance from an LED ranges from 1 to 10 km depending on the design of the optical system. Importantly, Haas notes that Li-Fi also works in non-line-of-sight situations as a result of its novel digital modulation techniques. “Interference can be managed more easily,” Haas says.

The development of white LED bulbs — essential for Li-Fi — followed the invention of blue LEDs, the importance of which was recognized when three Japanese researchers were awarded the 2014 Nobel Prize for Physics to for their work in this field. The UK-based pureLiFi company is partnering with Texas-based National Instruments to develop the technology.

“Light as a service will be rolled out and mobile operators will also provide lighting to homes, offices and public places,” Haas foresees. “Our home appliances will be Li-Fi- enabled through the LED status lights.”

He sees hundreds of new companies emerging that will develop new applications that the Li-Fi- networked world will enable. The technology is generating buzz in a number of industries. Most recently, a presentation by Haas and colleagues received a best paper award at the 2015 IEEE 81st Vehicular Technology Conference. The award was given for Li-Fi’s a novel technique to effectively manage interference.

Curt Harler is a technology writer and a regular contributor to SD&I magazine. Email him at [email protected].