LiFi stands for Light Fidelity and is a communication technology that uses light to transmit data between two devices wirelessly. Transmission can occur in the infrared, visible or ultraviolet spectrums. However, since they cannot penetrate walls and can get attenuated by the medium, LiFi is limited to short distances. Light reflected off walls can be used to extend the range. Light does not get affected by electromagnetic fields and this makes it suitable to use it in conjunction with other systems like radar.
Every light fixture in the building can contain a modem and chip to facilitate the communication. Since the light flickers at a very high frequency, it will not be visible. The fundamental requirements on the hardware to set up a LiFi network is quite small making it a viable candidate to scale. Every light based IoT device could possibly be used as a node in a LiFi network. Although they are limited to confined spaces, without much interferences from the sun. If that can be solved in some way, there is a huge potential for disruption. Traffic lights and vehicles in the vicinity will be able to talk to each other. Aircrafts and the ATC could use it as a communication channel. Cameras can be connected to all the lighting equipment in a movie set. Then the important question to ask is if the hardware will become so cheap that it would be a better option than using a BT or any other RF based hardware and software stack.