Like Wi-Fi, Li-Fi wireless and uses for data transmit with high speed and 100 times faster than Wi-Fi. Both Wi-Fi and Li-Fi transmit data over the electromagnetic spectrum, but Wi-Fi utilizes radio waves, Li-Fi uses visible light which has much wider bandwidth and it is a part of optical wireless communication technology.
Li-Fi works by flashing LED lights on and off at incredibly fast speeds, sending data to a reciever in binary code. The flashes occur so fast that they are not seen by the naked eye. The infrastructure is already there. We can use the LED bulb we already have, with some tweaking.
Researchers at the University of Oxford achieving bi-directional speeds of 224Gbps in lab. Using a 224Gbps speed would technically allow for 18 movies of 1.5GB to be downloaded in a single second.
Li-Fi was invented by Professor Harald Haas, from the University of Edinburgh in the UK, when he demonstrated in TED Global Talk in 2011 that by flickering the light from a single LED, he could transmit far more data than a celluar tower.
Li-Fi is wireless and uses similar to wifi 802.11 protocols but it uses Visible Light Communication (VLC) that uses visible light between 400 and 800 teraherts (THz).
Wi-Fi cannot be replaced with Li-Fi, but these two technologies could be used together to achieve more efficient and secure networks.
Li-Fi also has limits, visible light can’t travel through walls where as radio waves travel. It also does not work outside in direct daylight since any light signals would be washed by light coming from the sun, Li-Fi is restricted by line of sight, so it won’t ever replace. Other limitations are, short range, low reliability and high installation costs.