Li-Fi is a visible light communication system that uses LED bulbs to transmit data wirelessly at very high speeds in a similar way to Wi-Fi. It was created by Prof. Harald Haas and industry groups are working to promote it. Li-Fi works by varying the intensity of light from an LED lamp to transmit digital signals. It has advantages over Wi-Fi like higher speeds, more security, and ability to use visible light spectrum. However, it also has disadvantages like limited range and susceptibility to light interference. If developed further, Li-Fi could be used in many applications and help transition to a greener future with wireless connectivity.

1. VISHAL PRAJAPATI
ROLL NO:34

2. OVERVIEW
• What is Li-Fi?
• History
• How it Works?
• Difference between Wi-Fi and Li-Fi
• Application of Li-Fi
• Advantages
• Disadvantages
• Conclusion
• Reference

3. WHAT IS LI-FI?
• Li-Fi ( Light Fidelity )
• It is a VLC (Visible Light Communications) system running wireless
communications travelling at very high speeds.
• It refers to light based communications technology that delivers a
high-speed, bidirectional networked, mobile communications in a
similar manner as Wi-Fi.

4. HISTORY
• Li-Fi is created by Prof. Harald Haas.
• In October 2011, companies and industry
groups formed the Li-Fi consortium, to
promote high-speed optical wireless
system.
• In August 2013, data rates of over 1.6
gigabits were demonstrated over a single
color LED.
• In October 2013, it was reported Chinese
manufacturers were working on Li-Fi
development kits.

5. HOW IT WORKS?

6. HOW IT WORKS?
Photodetector

8. DIFFERENCE BETWEEN WI-FI AND LI-FI
• Wi-Fi transmits data with the help of Wi-Fi router using radio
waves whereas Li-Fi transmits data with the help of LED bulbs
using light.
• Wi-Fi is great for general wireless coverage within building and Li-
Fi is ideal for high density wireless date coverage in Limited area.
• Wi-Fi signals transfer through the walls and Li-Fi lights not transfer
through the walls.
• In Wi-Fi security is less and Li-Fi security is high.

9. APPLICATION OF LI-FI
• Airlines
• Underwater
• Smart Lighting
• Connectivity between more then two devices.
• Location Based Services (LBS)

10. ADVANTAGES
• Li-Fi can solve problems related to the insufficiency of radio
frequency bandwidth because this technology uses Visible light.
• Speed is Fast.
• It is Secure.
• Li-Fi has low implementation and maintenance costs.

11. DISADVANTAGES
• Light can't pass through objects.
• High installation cost of the VLC systems.
• Interferences from external light sources like sun, light, normal
bulbs, opaque materials.
• Limited Range

12. CONCLUSION
• If this technology can be put into practical use, every bulb can be
used something like a Wi-Fi hotspot to transmit wireless data and
we will proceed toward the cleaner, greener, safer and brighter
future.

13. REFERENCE
• http://www.lifi-centre.com
• http://purelifi.com
• http://youtube.com
• http://www.techworld.com
• http://newtecharticles.com
• http://www.axrtek.com

14. Thank