A New Era
Let’s leave high speed broadband internet aside for a while. Because finally, after many years of expectations and speculations, a new viable alternative to replace our two decades’ old Wi-Fi technology is here. And it’s hundreds and hundreds of times faster! Based on visual light communication (VLC), Light Fidelity (Li-Fi) is a fully networked wireless communication technology which uses light to transmit data at speeds up to 226 gigabits per second. That’s right. 226.
Li-Fi uses light from LED bulbs as a medium for delivering data. It does this by switching the current to the LEDs on and off at a very high rate; the flickering is so fast it can’t be noticed by the human eyes. Afterwards, this flickering is converted into electrical signals, which in turn can be used for data transmission purposes.
TheÂ term Light Fidelity or Li-Fi was coined by Harold Haas, professor at the University of Edinburgh. He introduced the technology at TEDGlobal, revealing its comparative advantages to Wi-Fi and showing how Li-Fi is both more efficient and more secure than Wi-Fi. He even demonstrated a working prototype on the spot, using a standard desk lamp with a LED bulb to stream a high definition video in front of the audience.
Haas convincingly argued Li-Fi’s superiority claiming that
Â “In the future we will not only have 14 billion light bulbs, we may have 14 billion Li-Fi’s deployed worldwide for a cleaner, greener and even a brighter future.”
Li-Fi vs Wi-Fi
In reality, Li-Fi should have been here already. There are growing concerns that the Wi-Fi technology has reached its zenith, which means that lower quality and price surges may be as inevitable as taxes (the FCC believes this as well). Even so, the technology is still both expensive and time-consuming to manage. Millions of radio stations placed around the world emit Wi-Fi waves daily. And most of the expenditure goes not into the creation of the radio waves, but into the maintenance of the stations which produce them.
There are also some health concerns with Wi-Fi. There is still no established scientific evidence, but it’s a fact that the radio waves used by your wireless network contain minute traces of radiation. And even though these are very small quantities, the radiation is, from time to time, at least, blamed as the reason behind irregular heartbeats and/or overall physical and mental instability; among children especially. Due to their smaller skulls and more absorbent brain tissues, it is speculated, children may intake more radiation than adults. And there are wi-fi networks everywhere, schools and kindergartens included. The problem is that even if there are side-effects, the technology may be too young for us to link it with any diseases. As is always the case with radiation, its effects are not instantly detectable, but rather accumulate over a longer period of time.
Li-Fi is an altogether different story. For one, it uses light as its medium for data transfer. Light, as we know, has been here for hundreds of years, and natural light ever since the creation of this planet. Consequently, we can be sure that it causes no damage to our health, but, on the contrary, is a necessity. Especially, nowadays, when in the absence of light, our ability to do meaningful tasks is not only severely limited, but also even impossible.
The Li-Fi spectrum is both free (no regulatory body owns the light) and estimated to be at least 10,000 times larger to that of Wi-Fi, making it conceivable to connect more users at the same time. In addition, no special plants or stations need to be devised or developed for Li-Fi to work: light is already available everywhere, from our homes to schools, on our roads and in our offices. So, Li-Fi technology is not only energy efficient, but it is also cost-effective. And already ubiquitous.
You don’t need to do anything more than attaching a microchip to our LED light bulbs and a light sensor to our phones, laptops or any other data-receiving device. The microchip will then start subtly modifying the light amplitude in the LED bulbs, thus sending 1 and 0 signals to our phones (or other devices). And this turning on and off happens so quickly, the human eye is unable to notice the flickering, making the LED bulbs usable as both Li-Fi transmitters and steady sources of light.
Li-Fi: A League of Its Own
Li-Fi comes with many other benefits as well. For example, as light cannot penetrate through walls like radio waves can, data cannot travel between rooms as well. This makes Li-Fi much more secure than Wi-Fi. It means that every room must have its own LED bulb installed, but also that, when it’s turned off, no connection can be established. And you don’t even have to turn off the light in case of emergencies: you can just put your hand to block the LED bulb and the flow of data will stop immediately.
Now, consequently, Li-FI seemingly has one major limitation as well. Installing a LED bulb in every room is neither expensive nor a problem; but using internet at night might be. Because a person can only dim the light at night, but he or she will not be allowed to turn it off at any moment.
But, even this may be a minor setback. Professor Haas believes that very soon, the technology will be able to allow users to dim the light to such an extent that it will look as if it is turned off. And we believe him. Because Li-Fi technology is not dependent on the intensity of light. It works by detecting changes in intensity, and not the intensity itself.
In essence, a Li-Fi system works very much like a remote control. As you probably know, a remote control uses short bursts of infrared light to send signals to your TV. Each burst of light contains a single data stream of information, just enough to tell your TV to change the channel, lower the volume or turn it off.
Where Li-Fi differentiates from remote control technology is in that its light spreads much farther than the infrared light utilized by remote controls, so one can move freely about the room and not worry about losing the connection. Also, Li-Fi is capable of sending not just a single data stream, but hundreds and hundreds – at much higher rate than those in a remote control.
The One Big Problem
Is there anything Li-Fi can’t do? Well, yes: there’s a big, big problem. Two-way communication.
This should probably not be an issue for large devices, such as laptops or TVs. Experience has taught us that no matter where they are located, light should be able to easily reach their sensors. It somehow always does. But what about mobile phones? Most of the time, they are in our pockets. And even when we use them, if there’s a light source behind us, we try to block its path so that we can see the screen better. But, with Li-Fi, this will immediately result in disconnecting the device. There’s a risk that even talking on the phone may produce the same result, since we inadvertently block the light every time we talk – with our hand from the one side and our head from the other.
If light is to be used as the only medium to transfer data, tech experts must find a way to tackle these hurdles as well. Because, it’s hard to imagine a world where people change their habits in order to use a faster network.
Li-Fi is so great that it still looks as if it will arrive in some distant future: it is 100 times faster, 10 times cheaper, and much safer than Wi-Fi; to quote the inventor of its name, it is also cleaner, greener and brighter way to use the internet.
But, the reality is that it is not ready as well: it’s just too easy to block light and, especially when it comes to phones, this is such a big hindrance that Li-Fi is sometimes deemed as “still too unreliable”.
Nevertheless, the possibilities seem endless. Light is ever-present and this makes all the difference. Very soon, thanks to Li-Fi, fast internet access may be made possible even in submarines or on mountain tops – and many other places taught to be out of any network’s reach. For example, unlike Wi-Fi, Li-Fi causes no electromagnetic interference, so you can say goodbye to airplane mode buttons in the very near future.
But, when exactly? Will it arrive soon and instantaneously mark the of the Wi-Fi era? Or will it work alongside a more advanced versions of Wi-Fi? Will it be something only submarines and airplanes prefer? Or will it signal the beginning of a new internet revolution?
Although it is estimated that the Li-Fi technology market will be worth 6 billion dollars by 2018, it’s still very difficult to give an answer to these questions, or even hazard a guess.
Time will tell best, we guess. It always does.