Light Fidelity or Li-Fi

What is Li-Fi?

Li–Fi is a Visible Light Communications system running wireless communications, traveling at very high speeds.

How does it work?

1. Li–Fi uses common household LED light bulbs to enable data transfer, reaching speeds of up to 224 gigabits per second.
2. Although Li-Fi bulbs would have to be kept on to transmit data, the bulbs could be dimmed to the point that they are not visible to humans and yet still functional.

How is it different from Wi-Fi?

1. Li-Fi and Wi-Fi are quite similar as both transmit data electromagnetically. However, Wi-Fi uses radio waves while Li-Fi runs on visible light.
2. Li-Fi signals cannot pass through walls. Therefore, it is useful for short-range transmission only.
3. Due to its shorter range, Li-Fi is more secure than Wi-Fi and it’s reported that embedded light beams reflected off a surface could still achieve 70 megabits per second.

Usage/Benefits of Li-Fi:

1. Freeing up the spectrum: When the traffic is diverted to Li-Fi (wherever available), already clogged cellular networks would be relieved of their burden.
2. Li-Fi can be used in electromagnetic sensitive areas like in aircraft cabins, hospitals, laboratories etc, without causing electromagnetic interference.
3. Smart lighting: Street lamps could be used to provide Li-Fi hotspots.
4. Electronic devices such as laptops, smart phones, tablets and other devices can interconnect directly using Li-Fi.
5. Transportation: Headlights and tail lights in vehicles are moving to LED and so are streetlights. Li-Fi can be used for vehicle to vehicle and vehicle to roadside communications for road safety and traffic management.
6. Li-Fi can also easily work underwater, where Wi-Fi fails completely, thereby throwing open endless opportunities for military and navigational operations.
7. Li-Fi with its impressive high speed could make a huge impact on the internet of things, with data transferred at much higher levels with even more devices able to connect to one another.
8. When developed fully, Li-Fi offers potential applications for a greener and cleaner future,
   riding on the rapid growth in the in the use of LED across the world.

Challenges/Disadvantages:

1. Light cannot pass through walls so Li-Fi would have mobility issues.
2. To make a Li-Fi network functional throughout the house, one will need these light bulbs in every room to have seamless connectivity.
3. The external lights (sunlight and other bulbs) may cause obstructions in Li-Fi’s transmission.
   path, thus it may create disturbances in the communication process.
4. Initial installation cost is high as Li-Fi receiving devices will require adapters to transmit data back to the transmitter.
5. One of the drawbacks is that the light needs to be on all the time to deliver connectivity.
6.  Another drawback is that Li-Fi is not very effective outdoors, meaning that public Li-Fi will not be able to replace public Wi-Fi networks anytime soon.

Conclusion:

If Li-Fi can be put into practical use, every LED lamp (indoor as well as outdoor) can be converted into something like a hot spot to transmit data to every mobile device to achieve universal broadband communication between devices.
Also, it presents another unique possibility: transmitting power wirelessly, wherein the Smartphone will not only receive data through Li-Fi but will also receive power to charge itself. Thus, it has immense potential which can be channelized for the more inclusive and better use of the internet.