LiFi vs WiFi | Difference between LiFi and WiFi
This page compares LiFi vs WiFi describes basic difference between LiFi and WiFi technologies. It covers basics of LiFi vs WiFi including their features, working operation, merits, demerits, applications etc. in order to derive difference between Lifi and wifi.
Let us go through some basic differences between LiFi and WiFi.
LiFi stands for Light Fidelity and WiFi stands for Wireless Fidelity. Both LiFi and WiFi technologies are mainly used for internet based applications. LiFi uses light as medium for data communication where as WiFi uses Electro-magnetic waves at various radio frequencies for data communication. Light undergoes reduced interference when compared to radio waves, and so can be used in more crammed environments. LiFi is an optical communication technology where as WiFi is a radio communication technology. Let us understand them individually before we derive a brief difference between them.
Following are the features of LiFi technology as depicted in the figure-1.
• LiFi (Light Fidelity) works based on VLC (Visible Light Communication) principle.
• It consists of two main components to drive the internet ,namely a LED Lamp and a Li-Fi Dongle.
• LiFi transmits data using light intensity modulation.
• It uses LEDs at transmit ends and Photo-detectors at receive ends. LiFi dongle uses photo-detectors as shown in the figure-1. Here LEDs are connected with internet server via lamp driver for internet connection.
• It uses light with wavelength ranging from 380 nm to 780 nm for data communication between LEDs and photo detectors.
• LiFi system supports three modes viz. peer to peer, star and broadcast.
• LiFi system uses modulation schemes such as OOK, VPPM, CSK.
• The PHY and MAC layers of LiFi system are defined in IEEE 802.15.7-2011 standard.
• LiFi technology is used for various applications which include street lights, sign boards, internet etc.
• It transfers data very rapidly and securely due LOS (Line of Sight) operation of optical signals.
Refer LiFi tutorial >> for more information.
Following are the features of WiFi technology as depicted in the figure-2.
• It consists of two important devices namely, a Wi-FI router or Access point(AP), Wi-Fi dongle and Wi-Fi stations.
• As shown a WiFi AP or Router is connected to the internet using a broadband cable or with cellular network. All the wifi compatible mobile phones, tablets or laptops are connected with AP (or router) to obtain internet.
• WiFi network operates in either of two modes viz. adhoc (i.e. BSS-Basic Service Set) and infrastructure (i.e. ESS-Extended Service Set).
• In BSS WLAN compliant stations (i.e. STAs) communicate directly. In ESS WLAN compliant STAs communicate with APs (Access Points) to access internet.
• WiFi supports different speeds and coverage ranges as per implemented standard in the devices (STAs, APs). 802.11a supports upto 54 Mbps, 11b upto 11 Mbps, 11n supports 72 Mbps/150 Mbps as per BW (20MHz/40MHz), 802.11ac wave-1 supports upto 1.3 Gbps (80MHz, 3 streams, 256QAM), 802.11ac wave-2 supports upto 3.5 Gbps (160MHz, 4 streams, 256QAM) etc. The distance coverage of 70 meters (indoor) to 250 meters (outdoor) can be achieved.
• WiFi network operates in different frequency bands viz. 2.4 GHz, 5 GHz.
• The PHY and MAC layers of WiFi system are defined in IEEE 802.11 standards. There are various versions of 802.11 which include 11a, 11b, 11g, 11n, 11ac etc.
Refer WLAN tutorial >> for more information.
Comparision between LiFi and WiFi | Tabular difference between LiFi and WiFi
Following table compares LiFi vs WiFi and derives difference between LiFi and WiFi technologies with respect to various features.
|Full form||Light Fidelity||Wireless Fidelity|
|Operation||LiFi transmits data using light with the help of LED bulbs.||WiFi transmits data using radio waves with the help of WiFi router.|
|Interference||Do not have any intereference issues similar to radio frequency waves.||Will have intereference issues from nearby access points(routers)|
|Technology||Present IrDA compliant devices||WLAN 802.11a/b/g/n/ac/ad standard compliant devices|
|Applications||Used in airlines, undersea explorations, operation theaters in the hospitals, office and home premises for data transfer and internet browsing||Used for internet browsing with the help of wifi kiosks or wifi hotspots|
|Merits(advantages)||Interference is less, can pass through salty sea water, works in dense region||Interference is more, can not pass through sea water, works in less dense region|
|Privacy||In LiFi, light does not pass thorugh the walls and hence will provide a much secure data transfer||In WiFi, RF signal passess thorugh the walls and hence there is a need to employ techniques to achieve secure data transfer.|
|Data transfer speed||About 1 Gbps||WLAN-11n offers 150Mbps, About 1-2 Gbps can be achieved using WiGig/Giga-IR|
|Frequency of operation||10 thousand times frequency spectrum of the radio||2.4GHz, 4.9GHz and 5GHz|
|Data density||Works in high dense environment||Works in less dense environment due to interference related issues|
|Coverage distance||About 10 meters||About 32 meters (WLAN 802.11b/11g), vary based on transmit power and antenna type|
|System components||Lamp driver, LED bulb(lamp) and photo detector will make up complete LiFi system.||requires routers to be installed, subscriber devices(laptops,PDAs,desktops) are referred as stations|
The Following table-2 summarizes the major difference between lifi and wifi technologies.
The following table-3 mentions speed (i.e. data rate) comparison between lifi and wifi and other wireless technologies such as IrDA, Bluetooth and NFC.
Following table-4 mentions difference between VLC and Wifi wireless technologies. As we know LiFi technology is based on VLC principle. This will help the reader to understand the difference between LiFi and WiFi in more detail.
Conclusion : From the above, we can compare LiFi vs WiFi and following difference between Lifi and wifi can be derived.
• LiFi technology is not a replacement of a widely used WiFi technology. Both the technologies LiFi and WiFi co-exist together based on their respective unique features.
• LiFi operates between wavelengths in the range from 380 nm to 780 nm whereas WiFi operates at different frequency bands viz. 2.4 GHz and 5 GHz.
• LiFi is used to exchange data incredibly rapidly and securely at much lower power level compare to WiFi.
Difference between LiFi and WiFi with other technologies
➤Links Related to LiFi technology, LiFi tutorial (LiFi tutorial-LiFi network, protocol, PHY, MAC, bands, modulation, Refer LiFi tutorial
➤LiFi physical layer (LiFi Physical Layer basics | LiFi PHY-I, II, III types, Refer LiFi physical layer
➤LiFi modulation types (OOK vs VPPM vs CSK-Difference between OOK,VPPM,CSK modulation, Refer LiFi modulation types
➤Basic Difference between LiFi and WiFi, Refer LiFi vs wifi
➤Products based on li-fi technology, Refer LiFi tutorial
➤Frame structures of LiFi Physical layer and MAC layer, Refer LiFi PHY and MAC layer frames
➤Wavelength bands used in LiFi, Refer LiFi Bands
➤Difference between LiFi and VLC, Refer LiFi vs VLC
➤Difference between VLC and WiFi, Refer VLC vs wifi
➤Difference between VLC and RF communication types, Refer VLC communication vs RF communication
➤Pros and Cons of VLC used in LiFi system, Refer Advantages and disadvantages of VLC
➤Difference between LiFi and GiFi, Refer LiFi vs GiFi
➤Difference between LiFi internet and WiFi internet, Refer LiFi internet vs WiFi internet
➤To know how LiFi works, refer Data Over Light basics
➤Difference between MiFi and WiFi, Refer MiFi vs WiFi
➤For channels used in WiFi, Refer WiFi RF Channels
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