Wi-fi

Wifi is the kind of networking technology that allows the internet without using cables but it uses radio waves as a medium. The name itself suggests wifi: wireless fidelity 

That is used in LAN(local area network)and allows to operate many devices such as laptops, mobiles, smart TV, and many other devices.it helps to provide broadband internet access. WIFi is based on the IEEE 802.11 family of standards.

HISTORY:

According to the research, the first wireless network was ALOHAnet in1997.Great Hawaiian Islands with a UHF wireless packet network

Then after some years IEEE 802.11 protocols, respectively. But actually

The initial origin of wifi is from the Netherlands in 1991 and finally, the first version of Wifi was 802.11 which was released in 1997 and provided 2MBit/s link speed and was updated in 1999 speed was 11Mbit/sand which got popular all over the world. and now in 2021, the average speed in India is 56.10 Mbit/s, the average fixed broadband upload speed is 53.68 Mbit/s. Speedtest recorded the average download speed on mobile connections in India as 12.15 Mbit/s.

WORKING:

These works on the same principle as other wireless techniques works.where it uses the radio frequency for the transmission of the signals from one device to another device. It receives the radio frequency the receiver needs to set a certain frequency  For WiFi this frequency happens to be 2.4Ghz and 5Ghz. It consists of a wireless adapter that will send the data in the form of radio waves that are received by the internet user by using a physical connection.  

Types of wifi:

There are four types of WIFI present:

• Wi-Fi-802.11a.

• Wi-Fi-802.11b.

• Wi-Fi-802.11g.

• Wi-Fi-802. 11n

1)Wi-Fi-802.11a: It is the first wireless standard to employ OFDM(orthogonal frequency division multiplexing). It also operates at the 5GHz band along with 52 subcarriers of OFMD with a maximum raw data rate of 54 Mbit/s.

2)Wi-Fi-802. 11b: It is the amendment to the IEEE 802.11 Wireless networking and appeared in the market in 1999 it has the raw data of 11Mbit/s. Apple was the first company ie. apple i-pad was first to have 802.11b.network 

3)Wi-Fi-802. 11g: It supports the maximum data of 54Mbps and has a bandwidth of 2.4GHZ. There are 52 OFMDsubcarriers among which 48 are the data and 4 are piolet subcarriers, as like a and b it also cant achieve the theoretical maximum rating in practice.

4)Wi-Fi-802. 11n:IEEE8002. 11n it is the wireless local area network that uses 802. 11 protocol.it also uses multiple antennas to increase the data rates.it uses 2.4GB or 5Gb of bandwidths and it supports the maximum theoretical transfer rate of 300Mbps.

APPLICATIONS Of WI-FI:

1. This wifi helps to connect more than one computer for internet usage.

2. Wi-Fi is not limited to personal usage this is versatile and can be used in many other ways.

3. With the facility of wifi, the device can access the internet not only from the working area but also even outside the area