ABSTRACT:
WiFi or wireless fidelity is the popular name known to the people as synonymous off wireless local area
network, base on the IEEE 802.11 standard and it is one of the brightest areas of communication
business. The precursor to Wi-Fi was invented in 1991 by NCR Corporation?AT/T (later Lucent & Agree
System) in Nieuwegein, the Netherlands [4]. It was initially intended for cashier systems; the first
wireless products were brought on the market under the name WaveLAN with speeds of 1Mbit/s to 2
Mbit/s [4]. Vic Hayes, who held the chair of IEEE 802.11 for 10 years and has been named the 'father of
Wi-Fi,' was involved in designing standards such as IEEE 802.111b, and 802.11a. However, Wi-Fi is an
industrial alliance whose goal is the certification of inter operability between IEEE 802.11card provided
with different vendors and the fidelity attribute does not have any reference as a mandatory constraint
for the adhesion to the standard. Wi-Fi uses both single carrier direct-sequence spread spectrum radio
technology (part of the larger family of spread spectrum system) and multi carrier OFDM ( Orthogonal
Frequency Division Multiplexing) radio technology [4]. These regulations then enabled the development
of Wi-Fi, its onetime competitor HomeRF and Bluetooth [4].