Wi-Fi is a well-known technology that utilizes electronic equipment to exchange data wirelessly (using radio waves) through a computer network, including high-speed Internet connections. WiFi Alliance defines WiFi as “any wireless local area network (WLAN) product based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard”. However, because most WLANs today are based on these standards, the term “Wi-Fi” is used in general English as a synonym for “WLAN”.
A device that can use Wi-Fi (such as a personal computer, video game console, smartphone, tablet or digital audio player) can be connected to a network source such as the Internet through a wireless network access point. Such access points (or hotspots) have a range of about 20 meters (65 feet) indoors and even more outdoors. Hotspot coverage can cover an area of a room with a wall that blocks radio waves or several square miles. This can be done by using several overlapping access points.
“Wi-Fi” is a trademark of the Wi-Fi Alliance and a brand name for products that use the IEEE 802.11 family of standards. Only Wi-Fi products that complete the Wi-Fi Alliance interoperability certification trial may use the name and trademark “Wi-Fi CERTIFIED”.
Wi-Fi has a changing security history. The first encryption system, WEP, proved easy to penetrate. Even higher quality protocols, WPA and WPA2, were later added. However, an optional feature added in 2007 called Wi-Fi Protected Setup (WPS), has a vulnerability that allows an attacker to get a WPA or WPA2 router password remotely in just a few hours.  Some companies recommend turning off the WPS feature. The Wi-Fi Alliance has since updated its testing plan and certification program to ensure all newly certified equipment is immune from harsh AP PIN attacks.
The history of 802.11 technology begins with the 1985 decision of the US Federal Communications Commission which released the GSM band for unlicensed use. In 1991, NCR Corporation and AT&T discovered the predecessor of 802.11 aimed at the cash register. The first wireless products are under the name WaveLAN. Vic Hayes was nicknamed “Father of Wi-Fi”. He was involved in designing the first IEEE standard. A large number of patents by many companies use the 802.11 standard. In 1992 and 1996, the Australian organization CSIRO obtained a patent for a method that would later be used on Wi-Fi to remove signal interference. In April 2009, 14 technology companies agreed to pay $ 250 million to CSIRO for violating their patents. This has led to Wi-Fi being touted as an Australian invention, although this has been the topic of a number of controversies. CSIRO won a $ 220 million lawsuit for violations of the 2012 Wi-Fi patent that required global firms in the United States to pay a license rights to CSIRO for $ 1 billion. In 1999, the Wi-Fi Alliance was formed as a trade association to hold the Wi-Fi trademark used by many products.
The term Wi-Fi, first used commercially in August 1999, was coined by a brand consulting firm called Interbrand Corporation. The Wi-Fi Alliance employs Interbrand to determine a name that is “easier said than” IEEE 802.11b Direct Sequence “. Belanger also said that Interbrand created Wi-Fi as a play on Hi-Fi (high fidelity); they also designed the Wi-Fi logo.
The Wi-Fi Alliance initially used the advertising slogan for Wi-Fi, “The Standard for Wireless Fidelity”, but later removed it from their marketing. Even so, a number of documents from Alliance in 2003 and 2004 still use the term Wireless Fidelity. There has been no official statement regarding the deletion of this term. The Yin-yang WiFi logo signifies a product interoperability certification. Non-Wi-Fi technology needed for fixed points such as the Motorola Canopy is usually called fixed wireless. Alternative wireless technologies include mobile phone standards such as 2G, 3G, or 4G.
To connect to a Wi-Fi LAN, a computer needs to be equipped with a wireless network interface controller. Combined computers and interface controllers are called stations. All stations share one radio frequency communication channel. Transmission on this channel is received by all stations that are within range. The hardware does not notify the user that the transmission was received successfully and this is called the best delivery mechanism. A carrier wave is used to send data in packets, called “Ethernet frames”. Each station is continuously connected to the radio frequency communication channel to pick up available transmissions.
A Wi-Fi device can connect to the Internet when it is within range of a wireless network connected to the Internet. Coverage of one or more access points (interconnected) – called a hotspot – can cover an area of several rooms up to several square miles. Coverage in a wider area requires several access points with overlapping coverage. Outdoor public Wi-Fi technology was successfully implemented in wireless mesh networks in London, United Kingdom.
Wi-Fi provides services in private homes, large streets and shops, as well as public spaces through free or paid Wi-Fi hotspots. Organizations and businesses, such as airports, hotels and restaurants, usually provide free hotspots to attract visitors. Enthusiastic users or authorities who want to provide services or even promote business in certain places sometimes provide free Wi-Fi access.
Routers that involve digital subscriber line or cable modem modems and WI-Fi access points, usually installed in homes and other buildings, provide Internet and network access to all equipment connected to the router wirelessly or wired. With the emergence of MiFi and WiBro (portable Wi-Fi routers), users can easily create their own Wi-Fi hotspots that are connected to the Internet through cellular networks. Now, Android, Bada, iOS (iPhone) and Symbian devices are able to create wireless connections. Wi-Fi also connects places that normally don’t have network access, such as kitchens and garden houses.