- Light-fidelity (LiFi) is a technology used for free-space communication using visible and near-visible light.
- It is similar to Wireless Fidelity (WiFi), a technology for wireless local area network communication using microwaves.
- Microwaves can pass through walls while transmitting signals whereas visible and near-visible light cannot pass through walls.
- Thus it makes LiFi signal network more secure.
- Scientists have recently added a new layer of security to LiFi.
- Light bounces off from walls and falls on the receiver.
- So wall boundaries can be used effectively for reflecting signals so that communication is maintained even without line-of-sight communication between the signal source and receiver.
- Receiving detectors can receive both direct and reflected signals.
- Walls painted with fluorescent and phosphorescent paints absorb and then emit light with marginal loss.
- The paints continue to emit light even several hours after the original source of light has been switched off.
- This makes the communication signal more effective and secure.
Basic Difference between LiFi and WiFi:
|Full form||stand for light fidelity||stands for wireless fidelity|
|Invented/Coined||Coined by Prof. Harald Haas in 2011||By NCR corporation on 1991|
|Operation||it transmits data using light by the help of LED bulbs||it transmits data using radio waves using wifi router|
|Technology||Present IrDA compliant devices||WLAN 802.11/b/g/n/ac/d standard compliant devices|
|Data Transfer Speed||About 1 Gbps||Ranges from 150Mbps to maximum of 2Gbps|
|Privacy||light is blocked by the walls hence provide more secure data transfer||walls cannot block radio waves so we need to employ more techniques to achieve secure data transfer|
|Frequency of operation||10, 000 times frequency spectrum of the radio||2.4Ghz, 4.9Ghz and 5Ghz|
|Coverage Distance||about 10 meters||about 32 meters(vary based on transmit power and antenna type)|
|Data density||work with high dense environment||work in less dense environment due to interference related issues|
|Bare minimum Components used||LED bulb, LED driver and photo detector||Routers, Modems and access points|
|Applications||Used in airlines, undersea exploration etc||Used for internet browsing with the help of wifi hotspot|