This document describe the difference between WiFi and LiFi in term of spectrum range, speed, range, interference and Security.

1. Wi-Fi and Li-Fi
WI-FI (WIRELESS FIDELITY)
Definition: “Wi-Fi transmits data using electromagnetic radio waves with the help of Wi-Fi router.”
Description: In this technology, Wi-Fi router, transmits data in the form of 1s and 0s; and emits photons with a wavelength
within the radio rangethat carries data in the area where Wi-Fi router is placed.Wi-Fi receiver devices (mobile,tables, laptops,
etc.) accept that photons and then decode the data.
 Spectrum range
Radio frequency spectrum range is less than visiblelightspectrum. Its operatingfrequency is 2.4 GHz - 5GHz.
 Speed
Data transfer speed is around 150 MB/s.
 Range
Its signal rangeis about32 meters (WLAN 802.11b/11g), vary based on transmitpower and antenna type.
 Interference
Interference is more, cannot pass through sea water, works in less denseregion.
 Security
Signal cannotbe blocked by the walls and henceneed to employ techniques to achievesecure data transfer.
Example: This technology can be used for Internet browsingand transfer data.
LI-FI (LIGHT FIDELITY)
Definition: “Li-Fi transmits data using visible light with the help of LED bulbs.”
Description: Li-Fi works much likethe infrared technology in your television.Infrared works on a simpleprinciple:a command
is given (e.g. “change channel”when you press a button on your remote control) and that input is turned into binary code. Th e
code is then transmitted via infrared lightwaves by your remote’s sensor,and the lightwaves are received by your TV’s infrared
sensor,which decodes the lightand performs the intended action.In caseof Li -Fi, LED bulbs transmitthe data by modulatingthe
lightwaves whilea photodiode on your phone or laptop picks up those lightwaves and decodes them.
 Spectrum range
Visiblelightspectrumhas 10,000 times broad spectrum in comparison to radio frequency spectrum.
 Speed
Data transfer speed is greater than 1GB/s (100 times faster than Wi-Fi).
 Range
Its signal rangeis based on LED light.
 Interference
Interference is less,can pass through salty sea water, works in dense region.
 Security
In Li-Fi, lightis blocked by the walls and hencewill providemore secure data transfer.
Example: This technology can be used in airlines,undersea explorations,operation theaters in the hospitals,officeand home
premises for data transfer and internet browsing.
Reference:
 https://en.wikipedia.org/wiki/Wi-Fi
 https://en.wikipedia.org/wiki/Li-Fi