Li-Fi : The Future Of Internet

By Fiza Rasool

Imagine a time when each of the lightbulbs in your house is a source of Internet. Imagine a scenario where, standing under a lightbulb for 1 minute, you would have downloaded around 5 movies in HD. Sounds like a dream, right? But thanks to Li-Fi technology, this dream will soon turn into reality. With this new technology, we can reimagine the role light plays in the universe.

Li-Fi stands for Light Fidelity and is a Visible Light Communications (VLC) system which uses light to send wireless data embedded in its beam. A Li-Fi enabled device converts the beam of light into an electrical signal. The signal is then converted back into data. The term was coined by German physicist Harald Haas during a TED Talk in 2011. He envisioned the idea of using lightbulbs as wireless routers.

LiFi bulbs are outfitted with a chip that modulates the light imperceptibly for optical data transmission. LiFi data is transmitted by the household LED bulbs and received by photoreceptors. If implemented meticulously, Li-Fi systems can reach transmission speeds which are upto 100 times faster (more than 1 Gigabit per second) than the current traditional Wi-Fi which works on radio waves.

Li-Fi which can be the future of data communication appears to be a fast and cheap optical version of Wi-Fi. It uses visible light of electromagnetic spectrum between 400 THz and 800 THz as optical carrier for data transmission and illumination.

The main components of a basic Li-Fi system contains the following:

a) A high brightness white LED which acts as transmission source.

b) A silicon photodiode with good response to visible light as the receiving element.

LED light bulbs can be dipped and dimmed, up and down at extremely high speeds, without being visible to the human eye. The tiny changes/pulses in the rapid dimming of LED bulbs is then converted by the ‘receiver’ into electrical signal. The signal is then converted back into a binary data stream that we would recognise as web, video and audio applications that run on internet enabled devices.

Li-Fi system connecting devices in a room
  1. The most astounding feature of Li-Fi is that unlike Wi-Fi, Li-Fi does not interfere with radio signals, making it an added advantage in terms of internet speeds where both Li-Fi and Wi-Fi are to be used, whereas Wi-Fi interferes with the nearby access points (routers). Not to mention, the spectacularly high speeds of Li-Fi over Wi-Fi.

2. Li-Fi is more secure and offers additional privacy because light is blocked by the walls and hence provides more secure data transfer. In case of Wi-Fi, the network is prone to hacking as it has a wider reach and radio frequency signal cannot be blocked by the walls. Which means that it’s harder for neighbours to get on your internet without paying for it.

  1. The coverage distance of Li-Fi is 10 metres while it is 32 metres for a Wi-Fi system.
  2. Li-Fi technology cannot be deployed outdoors in sunlight or in any unstable conditions, so it cannot potentially work in darkness in the absence of LED bulbs. Besides, more LED brightness added to the time we already spend looking at screens isn’t great for our eyes, especially if those LEDs will technically never be off. You may not be able to receive internet service if there’s a wall between you, your light and your LiFi receiver.

Li-Fi coverage can be limited to a small lit area such as a tent. Thus it can limit access to sensitive information under specific light and in areas where mobile phones can’t be used such as ammunition dumps.

An underwater internet connection is what will set Wi-Fi and Li-Fi apart. Light can travel through water unlike Wi-Fi’s radio signals that will be swallowed up by the water. This could change the way underwater vehicles communicate with one another.

Due to its impressive speeds, Li-Fi could make a huge impact on the internet of things. With data being transferred at a much higher level, even more internet-enabled devices will be able to connect to one another.

Cities could definitely benefit from Li-Fi enabled street lights to provide internet access to mobile phones. This public internet access could make walking home at night safer and also help with tourism by providing an outlet for local information.

Car headlights and rear lights could be fitted with Li-Fi enabled LED lightbulbs, which in turn could lead to car-to-car communication.

Li-Fi has a shorter range than Wi-Fi and because of this, is more secure than Wi-Fi. This is because the shorter the range, the less chance of malicious interceptions within the data stream. This could be very useful in industries that handle large counts of sensitive data, for example healthcare.

The LED bulbs in traffic lights could provide drivers with weather conditions and traffic updates while they wait at a traffic light.

Each of our devices will be connected to the internet, as we move into the Internet of Everything era. Is Wi-Fi upto the task of handling all that internet traffic alone? The short answer is no.

With the ever-growing demand for connectivity, LiFi would be able to combine illumination and wireless data transmission to accelerate the relay of data across the globe. It can be considered as incredible companion of wifi technology.

The company started by Professor Herald Haas in 2012 known as pureLifi is performing experiments and enormously researching the advancements in this field. A startup known as Velmenni is at the forefront of this technological revolution in India. There is certainty of development of future applications of the Li-Fi which can be extended to different platforms and various walks of human life. This technology has the potential to become mainstream and ubiquitous, so gear up for it!