1. History and Development of Wi-Fi:
– U.S. FCC released ISM bands for unlicensed use in 1985.
– NCR Corp. and AT&T invented precursor to 802.11 in 1991.
– CSIRO in Australia lodged patent for Wi-Fi in 1992.
– Wi-Fi Alliance formed in 1999.
– Apple adopted Wi-Fi for iBook laptops in 1999.
– Name ‘Wi-Fi’ coined by Interbrand in 1999.
– Wi-Fi logo created by Interbrand.
2. Wi-Fi Technology Overview:
– Operates on IEEE 802 protocol family.
– Uses 2.4GHz and 5GHz radio bands.
– Can achieve speeds up to 9.6Gbit/s.
– Range indoors about 20m, outdoors up to 150m.
– Spectral efficiency and speed have increased over time.
3. Wi-Fi Alliance and Certification:
– Wi-Fi Alliance restricts use of ‘Wi-Fi Certified’ term.
– Over 3.05 billion Wi-Fi-enabled devices shipped annually.
– Wi-Fi Alliance ensures interoperability certification testing.
– Manufacturers with membership in Wi-Fi Alliance can mark products with the Wi-Fi logo.
– Certification process includes conformance to IEEE 802.11 standards, WPA, WPA2 security standards, and EAP authentication standard.
4. Wi-Fi Uses and Applications:
– Provides Internet access through wireless routers and access points.
– Many university campuses provide Wi-Fi coverage for students and staff.
– City-wide Wi-Fi networks implemented in various cities globally.
– Wi-Fi positioning systems for geolocation.
– Different Wi-Fi versions operate on various radio wavebands with varying data rates.
5. Performance Factors and Interference in Wi-Fi:
– Range depends on frequency band, power output, and antenna type.
– Throughput can be affected by interference and congestion.
– Interference from other devices impacts Wi-Fi throughput.
– Regulatory measures like Dynamic Frequency Selection are used to avoid interference.
– Proper network planning can help improve Wi-Fi throughput.
Wi-Fi (/ˈwaɪfaɪ/) 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. 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.
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| Introduced | 21 September 1997 |
|---|---|
| Compatible hardware | Personal computers, gaming consoles, smart devices, televisions, printers, security cameras |
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. Non-compliant hardware is simply referred to as WLAN, and it may or may not work with "Wi-Fi Certified" devices. As of 2017,[update] the Wi-Fi Alliance consisted of more than 800 companies from around the world. As of 2019,[update] over 3.05 billion Wi-Fi-enabled devices are shipped globally each year.
Wi-Fi uses multiple parts of the IEEE 802 protocol family and is designed to work seamlessly with its wired sibling, Ethernet. Compatible devices can network through wireless access points with each other as well as with wired devices and the Internet. 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. Wi-Fi most commonly uses the 2.4 gigahertz (120 mm) UHF and 5 gigahertz (60 mm) SHF radio bands, with the 6 gigahertz SHF band used in newer generations of the standard; these bands are subdivided into multiple channels. Channels can be shared between networks, but, within range, only one transmitter can transmit on a channel at a time.
Wi-Fi's radio bands work best for line-of-sight use. Many common obstructions, such as walls, pillars, home appliances, etc., may greatly reduce range, but this also helps minimize interference between different networks in crowded environments. 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. Hotspot coverage can be as small as a single room with walls that block radio waves or as large as many square kilometers using many overlapping access points with roaming permitted between them. Over time, the speed and spectral efficiency of Wi-Fi have increased. As of 2019,[update] some versions of Wi-Fi, running on suitable hardware at close range, can achieve speeds of 9.6 Gbit/s (gigabit per second).
English
Noun
wi-fi (uncountable)
- Alternative spelling of Wi-Fi
Polish
Etymology
Borrowed from English Wi-Fi.
