Introduction to Wi-Fi Network

Wireless network standardized by IEEE802.11 and certified Wi-Fi Alliance use radio waves for communication. In wireless LAN (WLAN) devices both transmit and receive radio signal and hence they referred as station. In Wi-Fi network generally there are two modes of operation is available. One is Ad-hoc mode and the other is infrastructure mode. 

Through Ad-Hoc mode stations can communicate with each other without any third party control as peer-to-peer fashion. For an example we need to connect with some computer through LAN. If they have build in Wi-Fi then you just have to enable ad-hoc mode to make the connection, no need for any cable connection or switch. This mode is well for temporary network and has some limitation. The function of ad-hoc mode is limited.

On the other hand infrastructure mode makes connections among other stations through wireless access point (WAP) which also connect a wired network with a wireless network. In a simple word access point is a device that allows stations to connect wirelessly within certain limit range. 

The data rates of Wi-Fi network differs according to which generation technology it uses. Now a day up to fourth generations technology available in Wi-Fi networks. It comes with different 802.11 wireless network standards. They are as follow:

Wi-Fi Technology with 802.11a works with frequency band of 5 GHz and use OFDM as coding technique which basic principle is to make segments of radio signal into several sub-signals then transmit. That reduces interference. Data rate is up to 54 megabits per second.

802.11b comes with CCK modulation technique and operates in 2.4 GHz frequency. But its use is limited in modern days because of its low speed which is 11Megabits per second. 

802.11g is similar with 802.11b in a way they both use same frequency band 2.4GHz but with OFDM technique 802.11g improves its speed up to 54 megabits per second.

The latest standard is 802.11n can use both 2.4GHz and 5 GHz frequency band and transfer data in rate of 140 Megabits per second which making it popular now a day.