Wi-fi

Wi-Fi (/ ˈwaɪfaɪ /) is a family of wireless network protocols and is based on the IEEE 802.11 standard, commonly used for local area network devices and Internet access. As of 2016, the Wi-Fi Alliance had more than 600 organizations worldwide. As of 2017, over 2.98 billion devices worldwide have Wi-Fi enabled. Personal computer desktops and laptops, smartphones and tablets, smart TVs, printers, smart speakers, cars and drone devices are included in Wi-Fi technology. Wi-Fi uses numerous parts of the IEEE 802 protocol family and is designed with interwork simulations with wired sibling Ethernet. Compatible devices can create networks through each other's wireless access points as well as wired devices and the Internet.

History

In 1985, the Federal Communications Commission (FCC), the telecom regulator of the United States, approved the opening of several anonymous alphabet bands known as Wi-Fi. Where it was allowed to be used without the need for a government license. Very few people knew about this move at the time; Also the ham-radio channel was an unlicensed spectrum. But the FCC employee, Michael Marcus, was a visionary engineer who took one-third of the spectrum from industrial, scientific and medical bands and left them open for use to communications entrepreneurs.

The so-called "garbage bands" at 900 MHz, 2.4 GHz and 5.8 GHz were already allocated for devices that could easily use radio-frequency power for any purpose other than communication: for example, microwave ovens that radiate for heat production Waves are used. The FCC has also made bands accessible for communication purposes, allowing any device to use radio waves. They used "spread spectrum" technology, originally developed for military use, to transmit a radio signal over a wide range of frequencies as opposed to the general method of transmitting a single and precisely defined frequency. This makes the signal harder to intercept but less easy to interface.

Although 1975 seemed like a dream come true for many, nothing special happened at that time. Ultimately, Wi-Fi technology was created for use in industry. Initially, local-area networks (LANs), such as Proxim and Symbol, create their own proprietary devices that can operate in obsolete bands but cannot communicate from one vendor's equipment to another. Inspired by the success of Ethernet, for example, the quality of wireline-networking can be mentioned, several vendors took it positively. If buyers are not confined to a particular seller's products, the chances of adopting the technology will increase at a much higher rate.

In 1986, the NCR Corporation, which wanted to use unlicensed spectrum to hook up wireless cash registrars. Engineer Victor Hayes was asked to make an early start. Mr. Hayes, along with Bruce Tuch of Bell Labs, visited the Institute of Electrical and Electronics Engineers (IEEE), where a committee defined Ethernet 802.3 speed as standard. A new committee was set up with Mr Hayes as chairman at a speed of 802.11, and new discussions continued.

The split market meant that it took a while for the various vendors to agree on its definition and outlined an acceptable standard based on the consent of 75% of the committee members. Finally, in 1997, the committee agreed on a basic specification. It was approved for data-transfer of two megabytes per second using two-speed spectrum technology, frequency hopping or direct sequence transmission. (Avoid interference from other signals by jumping between the first radio frequency, spreading out the signal over the wide band of the second frequency.)

The new standard was published in 1997, and engineers immediately began working on a new venture to work with prototype equipment. Two types of bands 1) 802.11b (which operates in the 2.4 GHz band) and 2) 802.11a (which operates in the 5.8 GHz band) were approved in December 1999 and January 2000, respectively. Initially 802.11b was developed by Richard van Nee of Lucent and Mark Webster of Intersil (then Harris Semiconductor).

The companies took the initiative to build devices compatible with 802.11b. But the specification was so long and complicated that it filled about 400 pages. Complications related to consistency still existed. Therefore, in August 1999, six companies টার Intercell, 3Kom, Nokia, Aernet (bought by CSO), Symbol and Lucent (which closed the Ezra Systems component division) jointly created the Wireless Ethernet Compatibility Alliance (WECA).

Use

There are many types of wireless technology where we can use Wi-Fi. Such as AM and FM radios, televisions, laptops, cellular phones, satellite signals such as GPS and television, two-way radios and Bluetooth.

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