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How LiFi Will Change The Way We Connect To The Internet - Wi-Fi vs Li-Fi
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How LiFi Will Change The Way We Connect To The Internet - Wi-Fi vs Li-Fi
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Modern life would not exist for most people without Wi-Fi. Humans now depend on that consistent and constant wireless connection that allows us to do everything we need in our daily lives: we can search for the meaning of life on Google or find out what the name of the actor is that plays a certain role on a television series on IMDB. We can find new recipes to try at home each night for dinner. We can use the Internet to do important research that enhances our lives, both at work and at home.
Wi-Fi also gives us the ability to wirelessly communicate with others via email, messaging services, and social media. Wi-Fi entertains us by allowing us to stream television and movie content directly on our TVs, smartphones, computers and tablets. Most recently, Wi-Fi has begun to allow us to have connected homes, allowing us complete control over everything from our thermostats to our coffee makers.
But even as wonderful as Wi-Fi is, it has its limitations, not to mention its security flaws. That’s where LiFi comes in, as an alternative to Wi-Fi that is not only unlimited but also more secure. But what is LiFi and how does it work?
What is Li-Fi?
Professor Harald Haas at the University of Edinburgh originally coined the term “LiFi” during a TED Talk he gave in 2011. There, he demonstrated the technology for the first time by showing how to use visible light as a way to transfer and receive data. This is in direct contrast with how Wi-Fi works, which uses the limited radio frequency spectrum to transmit information.
We sat down with Haas to speak about LiFi and discuss what it is and how it offers benefits that Wi-Fi cannot.
LiFi works by using LED lights in a way to encode information by changing the intensity of the light,” Haas says in an interview. “We can change the intensity very rapidly and the binary information that you want to transmit is encoded in subtle changes in the intensity of the light. The flicker that is generated is not visible by the human eye: it’s far too fast. It’s much faster than the refresh rate of a screen of a computer
The idea is that in the near future, LED light bulbs will contain microchips that receive data and then uses these subtle changes in the light intensity to transmit that data.
“The microchip would then take the binary information and encode that in these sudden changes in the intensity and then at the other end of the receiver, we would have a photodiode – a very sensitive device – that would then capture the flicker,” Haas explains. “It’s binary information, so it would be decoded from that end. So we have a complete wireless communication by light.”
Haas began looking at how to use LED light to transmit and receive data 15 years ago when he worked for Siemens Mobile in Germany. At the time, his research revolved around what is now known as 4G.
“It was clear that we were at a transition from mobile telephony to mobile multimedia and it’s really fully taken off with with the advent of the smartphone,” Haas says. “It was very clearly a trend – there is a 60 percent annual growth rate in wireless data – that at one point the radio spectrum will not be sufficient.”
The Advantages of LiFi
1. Unlimited Spectrum
This is one of the biggest disadvantages of Wi-Fi: it operates on the very limited radio spectrum. This is also one reason why Wi-Fi often slows down to a crawl and completely fails when many people are using the same network. And with more people getting connected than ever before, Wi-Fi will ultimately run out of spectrum to serve the populace.
But the beauty of LiFi is that it has an unlimited spectrum. Many people can connect to the same LiFi network at one time without any issues. Haas states that LiFi offers at least a thousand times more spectrum than the entire radio frequency spectrum.
“And that’s why I’ve looked out of the box into what is available as part of the electromagnetic spectrum,” Haas says. “And radio is a child of that family, and another child of that family is invisible light, and the wireless LEDs came out and we looked into ways we can increase the data rate and this is where we hopefully, I think, made pioneering contributions.”
2. Security
Something that comes up often with Wi-Fi is that it is often not secure, leaving personal data out there in the open for anyone to easily come by it, grab it and use it with malevolent intent, including faking networks to stealing identities. There’s also now an issue of more people using the Internet of Things (Internet of Things), meaning that their cars and their houses are constantly connected, making those things an easy mark for hackers.
“We still read in the news that people hack and fake a Wi-Fi access point and in that way, they get access to information people who try to access it,” Haas says. “And LiFi is more difficult because the coverage of a typical light is roughly about 10 square meters. So anyone who is trying to tamper, or tries to eavesdrop, is in the vicinity.”
Walls block light, so anyone outside of a specific room does not have access to LiFi data transmitted within that room. And that is one very unique advantage that LiFi has over its Wi-Fi counterpart.
3. Speed
LiFi is also faster than Wi-Fi, especially when there is more than one person using the same network. Every time someone new logs into an existing Wi-Fi network, that network slows down because that’s one more person sucking up bandwidth on that connection. This isn’t the case, though, with LiFi.
“The other advantage is that we can have much better re-use of the spectrum,” Haas says. “So what that means is if you have four Wi-Fi access points in a room, you usually don’t get four times the data rate because these access points interfere with each other and the interference reduces the data rate. However, you can have easily four LED light bulbs in a room, and you can have four times the capacity of a single LED lamp because light is more confined in space and therefore, creates less interference.”
At the moment, on paper, the fastest Wi-Fi delivers only 7 gigabits. But according to a new paper submitted by Haas on the subject, LiFi delivers a whopping 15 gigabit.
4. Range
Because of the fact that walls block light, one might think that the range of LiFi would limit its use. However, Haas explains that this is simply not the case. Because we use light in almost every aspect of our lives, LiFi could exist all around us and work without any problems, even when there are walls present.
“People think that it’s a line of sight technology – that you need this actual line of sight for connection, but you don’t,” he says. “You can also turn the receiver away from the transmitter and if there are enough reflections from the floor or from surrounding furniture, then it would still be able to transmit and receive. And also range, if you consider a car, for example, a car headlight – look at the latest one that I used in BMWs – they have a range of 600 meters. So you have a very focused light cone and cover 600 meters. And so that means you can also transmit data over 600 meters. It’s really a question of how what’s the use case, what’s the application of LiFi?”
Who can use LiFi?
It might seem that LiFi is only useful for certain industries, and it is well-suited for more than others. Obviously, businesses such as banks, insurance companies, and corporate headquarters could benefit from the security that LiFi offers. But other applications include factories.
“What is also very important is that we now are going into the industry 4.0, or the industrial Internet of Things, where there are so many robots in a manufacturing hall that need data in order to give them the instructions of what they manufacture and how ” Haas says. “And there is so much electromagnetic interference, that’s one reason that Wi-Fi doesn’t really work there. In the other case, you don’t want to have anyone to carry out any espionage of intercepting the Wi-Fi links outside the manufacturing hall. Security, data rate and robustness play a major role in that environment.”
But the Internet of Things is also something now being adopted in many homes. So LiFi could benefit those people, too. Having Wi-Fi connected homes and security systems means that those homes are now easier to break into using other technologies on those connections. Many home services are now tied into smartphones, too, and it’s become a huge part of daily lives. LiFi will make those connections more secure, as well as offer the bandwidth needed to continue moving personal technology in that direction.
However, LiFi has a great potential for many other applications, too. It’s safer to use in hospital and medical settings because it does not emit electromagnetic signals that can interfere with medical scanners or MRI machines. It could also work well for underwater communications, where the radio frequency is all but useless. With LED headlights and tail lights being introduced into vehicles, LiFi could also allow automobiles, street lamps, and traffic signals to communicate wirelessly, assisting with traffic communication and safety. LiFi can also improve location-based services: imagine a future where you’re driving down the street and a billboard changes to offer up advertising on a product or service that you’re actually interested in, based on your current location.
For those who have ever flown on an airplane and used its Wi-Fi knows that the connection is often spotty, at best. As airplanes already use LED lights in their cabins, LiFi could solve that problem and offer a better way for passengers to receive and send data with their mobile devices.
Even the toy market can benefit from LiFI, allowing for low-cost communication for interactive toys, which is an up and coming market for the toy industry.
The Future of LiFi
Haas co-founded Pure LiFi in 2012 with hopes that the company will lead the way for the future of LiFi technology. He feels that LiFi is a transformative technology, one that will change the way that we use the Internet and connect many devices and appliances to the Internet of Things. He also believes that this technology will change the way lighting companies view their industry by changing their business models to offer services instead of just products.
“In the future, our ceilings will be computers that provide lighting, as one of the hundreds of applications, as part of many more, as part of smart homes and smart environments,” he says. “And the implication of that is that the lighting industry will expand their distance models into the classic domain of wireless communications and it’s foreseeable that the lighting industry, lighting firms will sell communications equipment in the future.”
Haas also feels that companies offering wireless communications will need to change to remain competitive in this technologically savvy environment, particularly when it comes to embracing LiFi.
“The wireless communications industry has a big problem in the spectrum crunch and they need to diversify into the spectrum and will automatically need to go into the wireless domain and the light domain and therefore, also react to the losses in market shares by the lighting industry,“ he says. “So they will react and they will then also diversify into perhaps selling lighting equipment and communications equipment.”
Haas hopes that Pure LiFi will be at the forefront of helping to change these industries, too.
“My vision of that is that it’s a fundamental land sliding change in two industries, and I hope that with LiFi, we will be as successful as American companies like Google and Apple,” he says. “It may be too bold of a mission, it may sound ridiculous, but I really have a vision that we create a very big company here.”
Behind this story
Robin Burks is a freelance journalist and writer.
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