Friday, August 5, 2016

LiFi vs WiFi



LiFi vs WiFi

 

WiFi Vs LiFi
WiFi Vs LiFi

This  basic difference between LiFi and WiFi technologies.

Following table mentions feature comparison between both. 


Feature

LiFi
WiFi
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 densy region 

Interference is more, can not pass through sea water, works in less densy region 
Privacy

In LiFi, light is blocked by the walls and hence will provide more secure data transfer
In WiFi, RF signal can not be blocked by the walls and hence 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

Lifi is not the replacement of wifi technology. It can be considered as incredible companion of the wifi technology. It operates between 380 nm to 780 nm optical range. LiFi is used to exchange data incredibly rapidly and securely at much lower power level compare to WiFi.

Thursday, August 4, 2016

Wi-Fi vs WiMAX


Wi-Fi Vs WiMAX

Wi-Fi vs WiMAX 

As wireless networking tends to spread itself outside offices and houses, it becomes utterly needed to invent protocols and systems which could support large scale networking with high data speeds. Several technologies for such wide accesses have been in the communications market such as 2G, 3G and the recent, 4G.  There are, however, many tradeoffs in using these technologies on a larger basis such as providing internet or stream multimedia wirelessly. This is why a new protocol, named WiMAX was incepted. Linguistically, it seems like an extended technological term to Wi-Fi, but there are several differences between these two protocols. This article will explore about various differences between WiFi and WiMax - the two wireless connectivity technologies share. 

1. Abbreviated Term: Wi-Fi stands for Wireless Fidelity, a term that was more of a marketing stint as it rhymed with Hi-Fi. WiMAX, on the other hand, stands for Worldwide Interoperability for Microwave Access, a term fulfilling technological as well as commercial requirements. 

2. Official Release: Wi-Fi was officially launched in the year 1997 where as WiMAX came to the picture in the year 2004.

3. IEEE Standards: Wi-Fi has been defined under IEEE 802.11x standards where x is various Wi-Fi versions. WiMAX is standardized under 802.16y family of wireless networking where y refers to various WiMAX versions. 

4. Versions of the Standard: Depending on several factors such as frequency, range, encryption, application etc., Wi-Fi has several versions of it such as 802.11b, 802.11g, 802.11n.On the similar factors, WiMAX has a number of different versions too:802.16a, 802.16d and 802.16e are some popular WiMAX versions.    

5. Frequency Band: Wi-Fi has been defined under ISM bands where user has to pay no extra charging for utilizing those bands. On the contrast, there is no bar on frequency usage in the WiMAX. This means that WiMAX protocols might work in the ISM bands or they might use a licensed frequency version for which the user probably would be charged. 

6. Range: An ideal Wi-Fi based network reaches around 100metres as it maximum range whereas an ideal WiMAX network can reach about 80-90kilometers in terms of range. 

7. Data Transfer Rates: Wi-Fi based networking can transfer data at speeds up to 54mbps. On the other hand, WiMAX networks exchange data at speeds upto 40mbps. In WiMAX, data transfer rates have more variation as distances to be covered are quite larger. 

8. Channel Bandwidth: Wi-Fi networks have a channel bandwidth of 20MHz, whereas WiMAX networks have a flexible bandwidth option which ranges from 1.25MHz to 20MHz. 

9. Bandwidth Efficiency: This term refers to bits of information sent per second per unit frequency. This is a measure of how qualitatively the channel is managed by the network. Bandwidth efficiency of a WiMAX channel (upto 5bps/s/Hz) is theoretically twice as efficient as Wi-Fi based networks (upto 0.44bps/s/Hz for 802.11a and 2.7bps/s/Hz for b/g/n standards). 

10. Difference in MAC Layer: MAC layer is an essential part of an OSI model. It defines communication procedures that a protocol uses.  Wi-Fi’s MAC layer uses CSMA/CA protocol which is not connection oriented while that in WiMAX is connection oriented. 

11. Encryption Techniques: Encryption techniques in WiMAX include Triple Data Encryption Algorithm and Advanced Encryption Standards. On the other hand, in Wi-Fi, encryption techniques are Advanced Encryption Standard (AES) and RC4. 

12. Authentication: Authentication is process under Network Security where connection is checked for its identity before being established.  Both these wireless networking technologies apply different set of protocols for authentication purposes. Wi-Fi uses Extensible Authentication Protocol (EAP) Wired Equivalent Privacy (WEP) security algorithms depending on the Wi-Fi version. On the other hand, WiMAX uses X.509 or PKMv2 as authentication algorithms. 

13. Applications: Wi-Fi and WiMAX, though being used for same purpose of data exchange, are designed to cater two completely different needs. Wi-Fi is needed to serve for household and corporate needs of interconnectivity. Wi-Fi technology connects printers to computer, gaming consoles to router etc.
WiMAX serves a larger inter-operable network. WiMAX can be used to provide internet services to a larger area where it can serve households, mobile phones and even Wi-Fi spots. WiMAX has a different hardware specification and currently WiMAX serving towers tend to be as tall as Wi-Fi towers. On the other hand, Wi-Fi antennas are small enough to be placed on 5 inch by 3 inch routers.