NCR's Vic Hayes, who held the chair of IEEE 802.11 for ten years, along with Bell Labs engineer Bruce Tuch, approached the Institute of Electrical and Electronics Engineers (IEEE) to create a standard and were involved in designing the initial 802.11b and 802.11a specifications within the IEEE. In 1991 in the Netherlands, the NCR Corporation and AT&T invented the precursor to 802.11, intended for use in cashier systems, under the name WaveLAN. These frequency bands include the same 2.4 GHz bands used by equipment such as microwave ovens, and are thus subject to interference. Federal Communications Commission released parts of the ISM bands for unlicensed use for communications. As of 2019, some versions of Wi-Fi, running on suitable hardware at close range, can achieve speeds of 9.6 Gbit/s ( gigabit per second). Over time, the speed and spectral efficiency of Wi-Fi have increased. Hotspot coverage can be as small as a single room with walls that block radio waves or as large as many square kilometres using many overlapping access points with roaming permitted between them. The range of an access point is about 20 m (66 ft) indoors, while some access points claim up to a 150 m (490 ft) range outdoors. may greatly reduce range, but this also helps minimize interference between different networks in crowded environments. Many common obstructions such as walls, pillars, home appliances, etc. Wi-Fi's radio bands work best for line-of-sight use. Channels can be shared between networks, but, within range, only one transmitter can transmit on a channel at a time.Ī newly installed home Wi-Fi network in April 2022 Wi-Fi most commonly uses the 2.4 gigahertz (120 mm) UHF and 5 gigahertz (60 mm) SHF radio bands these bands are subdivided into multiple channels. Different versions of Wi-Fi are specified by various IEEE 802.11 protocol standards, with different radio technologies determining radio bands, maximum ranges, and speeds that may be achieved. Compatible devices can network through wireless access points with each other as well as with wired devices and the Internet. Wi-Fi uses multiple parts of the IEEE 802 protocol family and is designed to work seamlessly with its wired sibling, Ethernet. As of 2019, over 3.05 billion Wi-Fi-enabled devices are shipped globally each year. As of 2017, the Wi-Fi Alliance consisted of more than 800 companies from around the world. Wi-Fi is a trademark of the Wi-Fi Alliance, which restricts the use of the term " Wi-Fi Certified" to products that successfully complete interoperability certification testing. These are the most widely used computer networks, used globally in home and small office networks to link devices and to provide Internet access with wireless routers and wireless access points in public places such as coffee shops, hotels, libraries, and airports to provide visitors. Wi-Fi ( / ˈ w aɪ f aɪ/) is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves.
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