Editing Wi-Fi (section)

==Uses==

=== Internet ===
[[File:SSID ESS.svg|thumb|An example of a service set called ''WiFi Wikipedia'' consisting of two basic service sets. The clients automatically [[roaming|roam]] between the two BSSs without the user having to explicitly connect to the second network.]]

Wi-Fi technology may be used to provide local network and [[Internet access]] to devices that are within Wi-Fi range of one or more routers that are connected to the Internet. The coverage of one or more interconnected access points can extend from an area as small as a few rooms to as large as many square kilometres. Coverage in the larger area may require a group of access points with overlapping coverage. For example, public outdoor Wi-Fi technology has been used successfully in [[wireless mesh network]]s in London. An international example is [[Fon Wireless|Fon]].

Wi-Fi provides services in private homes, businesses, as well as in public spaces. [[Wi-Fi hotspot]]s may be set up either free of charge or commercially, often using a [[captive portal]] webpage for access. Organizations, enthusiasts, authorities and [[business]]es, such as airports, hotels, and restaurants, often provide free or paid-use hotspots to attract customers, to provide services to promote business in selected areas. [[Router (computing)|Routers]] often incorporate a [[digital subscriber line]] modem or a [[cable modem]] and a Wi-Fi access point, are frequently set up in homes and other buildings, to provide Internet access for the structure.

Similarly, battery-powered routers may include a [[mobile broadband modem]] and a Wi-Fi access point. When subscribed to a cellular data carrier, they allow nearby Wi-Fi stations to access the Internet. A number of smartphones have a built-in [[mobile hotspot]] capability of this sort, though carriers often disable the feature, or charge a separate fee to enable it. Standalone devices such as [[MiFi]]- and [[WiBro]]-branded devices provide the capability. Some laptops that have a cellular modem card can also act as mobile Internet Wi-Fi access points.

Multiple traditional university campuses in the developed world provide at least partial Wi-Fi coverage. [[Carnegie Mellon University]] built the first campus-wide wireless Internet network, called [[Wireless Andrew]], at its [[Pittsburgh]] campus in 1993 before Wi-Fi branding existed.<ref>{{cite web|url=http://popcitymedia.com/innovationnews/wifi100511.aspx|title=How Wi-Fi got its start on the campus of CMU, a true story|last=Smit|first=Deb|date=5 October 2011|website=[[Pop City]]|archive-url=https://web.archive.org/web/20111007191316/http://www.popcitymedia.com/innovationnews/wifi100511.aspx|archive-date=7 October 2011|url-status=dead|access-date=6 October 2011}}</ref><ref>{{cite web | title=Wireless Andrew: Creating the World's First Wireless Campus | publisher=Carnegie Mellon University | year=2007 | url=http://www.cmu.edu/corporate/news/2007/features/wireless_andrew.shtml | access-date=6 October 2011 | url-status=dead | archive-url=https://web.archive.org/web/20110901202026/http://www.cmu.edu/corporate/news/2007/features/wireless_andrew.shtml | archive-date=1 September 2011 }}</ref><ref>{{cite book|url=https://books.google.com/books?id=-OMoL5Irm08C&pg=PA121|title=The Innovation Journey of Wi-Fi: The Road to Global Success|last1=Lemstra|first1=Wolter|last2=Hayes|first2=Vic|last3=Groenewegen|first3=John|publisher=Cambridge University Press|year=2010|isbn=978-0-521-19971-1|page=121|author-link2=Vic Hayes|access-date=6 October 2011|archive-url=https://web.archive.org/web/20121112175135/http://books.google.com/books?id=-OMoL5Irm08C&pg=PA121|archive-date=12 November 2012|url-status=live}}</ref> A number of universities collaborate in providing Wi-Fi access to students and staff through the [[Eduroam]] international authentication infrastructure.

=== City-wide ===
{{Further|Municipal wireless network}}
[[File:Metro Wireless Node.jpg|thumb|An outdoor Wi-Fi access point]]

In the early 2000s, multiple cities around the world announced plans to construct citywide Wi-Fi networks. There are a number of successful examples; in 2004, [[Mysore]] (Mysuru) became India's first Wi-Fi-enabled city. A company called WiFiyNet has set up hotspots in Mysore, covering the whole city and a few nearby villages.<ref>{{cite web|url=https://www.telegraphindia.com/opinion/say-hello-to-india-s-first-wirefree-city/cid/1025843|title=Say Hello to India's First Wirefree City|last=Verma|first=Veruna|date=20 August 2006|work=[[The Telegraph (Calcutta)|The Telegraph]]|archive-url=https://web.archive.org/web/20120120071302/http://www.telegraphindia.com/1060820/asp/opinion/story_6632793.asp|archive-date=20 January 2012|url-status=live}}</ref>

In 2005, [[St. Cloud, Florida]] and [[Sunnyvale, California]], became the first cities in the United States to offer citywide free Wi-Fi (from [[MetroFi]]).<ref>{{cite web|url=http://www.besttech.com.tr/urun/bq100-gsm-role-kontrol/|title=Sunnyvale Uses Metro Fi|publisher=besttech.com.tr|language=tr|archive-url=https://web.archive.org/web/20150722113251/http://www.besttech.com.tr/urun/bq100-gsm-role-kontrol/|archive-date=22 July 2015|url-status=dead}}</ref> [[Minneapolis]] has generated $1.2 million in profit annually for [[Minneapolis wireless internet network|its provider]].<ref>{{cite news|url=http://www.startribune.com/business/111286134.html|title=Minneapolis moves ahead with wireless|last1=Alexander|first1=Steve|date=5 December 2010|work=[[The Star Tribune]]|archive-url=https://web.archive.org/web/20101209140054/http://www.startribune.com/business/111286134.html|archive-date=9 December 2010|url-status=dead|last2=Brandt|first2=Steve}}</ref>

In May 2010, the then [[London]] mayor [[Boris Johnson]] pledged to have London-wide Wi-Fi by 2012.<ref>{{cite news|url=http://news.bbc.co.uk/2/hi/uk_news/england/london/8692103.stm|title=London-wide wi-fi by 2012 pledge|date=19 May 2010|work=[[BBC News]]|access-date=19 May 2010|archive-url=https://web.archive.org/web/20100522121915/http://news.bbc.co.uk/2/hi/uk_news/england/london/8692103.stm|archive-date=22 May 2010|url-status=live}}</ref> Several [[London boroughs|boroughs]] including [[City of Westminster|Westminster]] and [[London Borough of Islington|Islington]]<ref>{{cite web|url=http://www.govtech.com/dc/118717|title=City of London Fires Up Europe's Most Advanced Wi-Fi Network|last=Bsu|first=Indrajit|date=14 May 2007|work=Digital Communities|access-date=14 May 2007|archive-url=https://web.archive.org/web/20080907195450/http://www.govtech.com/dc/118717|archive-date=7 September 2008|url-status=dead}}</ref><ref>{{cite web|url=https://www.zdnet.com/home-and-office/networking/london-gets-a-mile-of-free-wi-fi/|title=London gets a mile of free Wi-Fi|last=Wearden|first=Graeme|date=18 April 2005|work=[[ZDNet]]|archive-url=https://web.archive.org/web/20151107174238/http://www.zdnet.com/article/london-gets-a-mile-of-free-wi-fi/|archive-date=7 November 2015|url-status=live|access-date=6 January 2015}}</ref> already had extensive outdoor Wi-Fi coverage at that point.

[[New York City]] announced a city-wide campaign to convert old [[phone booths]] into [[digital kiosk]]s in 2014. The project, titled [[LinkNYC]], has created a network of kiosks that serve as public Wi-Fi hotspots, high-definition screens and [[landline]]s. Installation of the screens began in late 2015. The city government plans to implement more than seven thousand kiosks over time, eventually making LinkNYC the largest and fastest public, government-operated Wi-Fi network in the world.<ref name="Forbes-PayPhonesWifiKiosks-2014">{{cite web|last=Chowdhry|first=Amit|date=19 November 2014|title=Pay Phones In NYC To Be Replaced With Up To 10,000 Free Wi-Fi Kiosks Next Year|url=https://www.forbes.com/sites/amitchowdhry/2014/11/19/linknyc-free-wifi/#11c29eb27028|access-date=17 September 2016|website=[[Forbes]]|archive-date=22 September 2016|archive-url=https://web.archive.org/web/20160922212101/http://www.forbes.com/sites/amitchowdhry/2014/11/19/linknyc-free-wifi/#11c29eb27028|url-status=live}}</ref><ref name="WNYC-GoodbyePayPhones-20162">{{cite news|last1=Gould|first1=Jessica|date=5 January 2016|title=Goodbye Pay Phones, Hello LinkNYC|work=[[WNYC]]|url=https://www.wnyc.org/story/goodbye-pay-phones-hello-linknyc/|access-date=26 January 2016|archive-date=20 August 2016|archive-url=https://web.archive.org/web/20160820213828/http://www.wnyc.org/story/goodbye-pay-phones-hello-linknyc/|url-status=live}}</ref><ref name="WashingtonPost-PayphoneOfTheFuture-2014">{{cite news|date=17 November 2014|title=New York City unveils the pay phone of the future{{snd}}and it does a whole lot more than make phone calls|newspaper=[[Washington Post]]|url=https://www.washingtonpost.com/news/wonk/wp/2014/11/17/new-york-city-unveils-the-payphone-of-the-future-and-it-does-a-whole-lot-more-than-make-phone-calls/|access-date=17 September 2016|archive-date=19 September 2016|archive-url=https://web.archive.org/web/20160919171319/https://www.washingtonpost.com/news/wonk/wp/2014/11/17/new-york-city-unveils-the-payphone-of-the-future-and-it-does-a-whole-lot-more-than-make-phone-calls/|url-status=live}}</ref><ref name="NYCGov-MayorAnnouncesWinner-20142">{{cite news|date=17 November 2014|title=De Blasio Administration Announces Winner of Competition to Replace Payphones with Five-Borough Wi-Fi Network|work=[[nyc.gov]]|publisher=[[Government of New York City]]|url=http://www1.nyc.gov/office-of-the-mayor/news/923-14/de-blasio-administration-winner-competition-replace-payphones-five-borough|access-date=17 November 2014|archive-date=7 June 2018|archive-url=https://web.archive.org/web/20180607153357/http://www1.nyc.gov/office-of-the-mayor/news/923-14/de-blasio-administration-winner-competition-replace-payphones-five-borough|url-status=live}}</ref><ref name="NYDailyNews-PayphonesReplaced-20162">{{cite news|last1=Alba|first1=Alejandro|date=5 January 2016|title=New York to start replacing payphones with Wi-Fi kiosks|work=[[New York Daily News]]|url=http://www.nydailynews.com/news/national/new-york-start-replacing-payphone-wi-fi-kiosks-article-1.2485429|access-date=26 January 2016|archive-date=24 June 2017|archive-url=https://web.archive.org/web/20170624191512/http://www.nydailynews.com/news/national/new-york-start-replacing-payphone-wi-fi-kiosks-article-1.2485429|url-status=live}}</ref> The [[UK]] has planned a similar project across major cities of the country, with the project's first implementation in the [[London Borough of Camden]].<ref>{{Cite web|last=McCormick|first=Rich|date=25 October 2016|title=Link brings its free public Wi-Fi booths from New York to London|url=https://www.theverge.com/2016/10/25/13401348/link-public-wi-fi-kiosk-london|access-date=25 July 2021|website=The Verge|language=en|archive-date=26 December 2016|archive-url=https://web.archive.org/web/20161226145341/http://www.theverge.com/2016/10/25/13401348/link-public-wi-fi-kiosk-london|url-status=live}}</ref>

Officials in South Korea's capital [[Seoul]] were moving to provide free Internet access at more than 10,000 locations around the city, including outdoor public spaces, major streets, and densely populated residential areas. Seoul was planning to grant leases to KT, [[LG]] Telecom, and SK Telecom. The companies were supposed to invest $44 million in the project, which was to be completed in 2015.<ref name="Voice of America">{{cite web|url=https://blogs.voanews.com/breaking-news/2011/06/15/seoul-moves-to-provide-free-city-wide-wifi-service/|title=Seoul Moves to Provide Free City-Wide WiFi Service|date=15 June 2011|website=[[Voice of America]]|archive-url=https://web.archive.org/web/20121110050549/http://blogs.voanews.com/breaking-news/2011/06/15/seoul-moves-to-provide-free-city-wide-wifi-service/|archive-date=10 November 2012|url-status=dead|access-date=1 April 2012}}</ref>{{update inline|date=September 2023}}

=== Geolocation ===
[[Wi-Fi positioning system]]s use known positions of Wi-Fi hotspots to identify a device's location.<ref name="KolodziejHjelm2017">{{cite book|author1=Krzysztof W. Kolodziej|author2=Johan Hjelm|title=Local Positioning Systems: LBS Applications and Services|url=https://books.google.com/books?id=aV3LBQAAQBAJ|date=19 December 2017|publisher=CRC Press|isbn=978-1-4200-0500-4|access-date=6 October 2019|archive-date=17 January 2023|archive-url=https://web.archive.org/web/20230117221756/https://books.google.com/books?id=aV3LBQAAQBAJ|url-status=live}}</ref><ref>.{{cite journal |last1=Wang |first1=C. |last2=Zheng |first2=X. |last3=Chen |first3=Y. |last4=Yang |first4=J. |date=September 2017 |title=Locating Rogue Access Point Using Fine-Grained Channel Information |journal=IEEE Transactions on Mobile Computing |volume=16 |issue=9 |pages=2560–2573 |doi=10.1109/TMC.2016.2629473 |issn=1558-0660 |doi-access=free}}</ref><ref>{{cite web |title=Cisco Prime Network Control System Configuration Guide, Release 1.0 - Chapter 6: Monitoring Maps [Cisco Prime Network Control System Series Appliances] |url=https://www.cisco.com/c/en/us/td/docs/wireless/ncs/1-0/configuration/guide/NCS10cg/maps.html |access-date=19 December 2020 |website=Cisco}}</ref> It is used when [[GPS]] isn't suitable due to issues like signal interference or slow satellite acquisition.<ref>Magda Chelly, Nel Samama. Detecting visibility in heterogeneous simulated environments for positioning purposes. IPIN 2010: International Conference on Indoor Positioning and Indoor Navigation, Sep 2010, Hoenggerberg, Switzerland. ⟨hal-01345039⟩ [https://hal.archives-ouvertes.fr/hal-01345039]</ref> This includes assisted [[GPS]], urban hotspot databases, and indoor positioning systems.<ref>Magda Chelly, Nel Samama. New techniques for indoor positioning, combining deterministic and estimation methods. ENC-GNSS 2009: European Navigation Conference – Global Navigation Satellite Systems, May 2009, Naples, Italy. pp.1 – 12. hal-01367483 [https://hal.archives-ouvertes.fr/hal-01367483/]</ref> Wi-Fi positioning relies on measuring signal strength ([[RSSI]]) and fingerprinting.<ref name=":2"/><ref>Y. Chen and H. Kobayashi, “Signal strength based indoor geolocation,” in Proceedings of the IEEE International Conference on Communications (ICC ’02), vol. 1, pp. 436–439, New York, NY, USA, April–May 2002.</ref><ref name=":7">{{Cite book|last1=Youssef|first1=M. A.|last2=Agrawala|first2=A.|last3=Shankar|first3=A. Udaya|title=Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003) |chapter=WLAN location determination via clustering and probability distributions |date=2003-03-01|pages=143–150|doi=10.1109/PERCOM.2003.1192736|isbn=978-0-7695-1893-0|citeseerx=10.1.1.13.4478|s2cid=2096671 }}</ref><ref name=":8">{{Cite book|last1=Youssef|first1=Moustafa|last2=Youssef|first2=Adel|last3=Rieger|first3=Chuck|last4=Shankar|first4=Udaya|last5=Agrawala|first5=Ashok|title=Proceedings of the 4th international conference on Mobile systems, applications and services |chapter=PinPoint |date=2006-01-01|series=MobiSys '06|location=New York, NY, USA|publisher=ACM|pages=165–176|doi=10.1145/1134680.1134698|isbn=978-1595931955|s2cid=232045615 }}</ref> Parameters like [[SSID]] and MAC address are crucial for identifying access points. The accuracy depends on nearby access points in the database. Signal fluctuations can cause errors, which can be reduced with noise-filtering techniques. For low precision, integrating Wi-Fi data with geographical and time information has been proposed.<ref>{{cite journal|last1=Danalet|first1=Antonin|last2=Farooq|first2=Bilal|last3=Bierlaire|first3=Michel|title=A Bayesian approach to detect pedestrian destination-sequences from WiFi signatures|journal=Transportation Research Part C: Emerging Technologies|volume=44|pages=146–170|doi=10.1016/j.trc.2014.03.015|url=http://infoscience.epfl.ch/record/199471|year=2014|bibcode=2014TRPC...44..146D }}</ref><ref name=":1"/>

The [[Wi-Fi RTT]] capability introduced in [[IEEE 802.11mc]] allows for positioning based on round trip time measurement, an improvement over the RSSI method.<ref>{{citation |url=https://www.sciencedirect.com/science/article/abs/pii/S1574119221000687 |title=Accurate indoor positioning using IEEE 802.11mc round trip time |date=2021 |doi=10.1016/j.pmcj.2021.101416 |access-date=2023-10-24 |last1=Hashem |first1=Omar |last2=Harras |first2=Khaled A. |last3=Youssef |first3=Moustafa |journal=Pervasive and Mobile Computing |volume=75 |s2cid=236299935 }}</ref> The [[IEEE 802.11az]] standard promises further improvements in geolocation accuracy.<ref>{{cite press release |url=https://standards.ieee.org/beyond-standards/newly-released-ieee-802-11az-standard-improving-wi-fi-location-accuracy-is-set-to-unleash-a-new-wave-of-innovation/ |title=Newly Released IEEE 802.11az Standard Improving Wi-Fi Location Accuracy is Set to Unleash a New Wave of Innovation |access-date=2023-10-24}}</ref><ref>{{cite web |url=https://blogs.arubanetworks.com/solutions/wi-fi-location-based-services-how-did-we-get-here/ |title=Wi-Fi location-based services: How did we get here? |date=27 February 2023 |access-date=2023-10-24}}</ref>

=== Motion detection ===
[[Wi-Fi sensing]] is used in applications such as [[motion detection]] and [[gesture recognition]].<ref>{{Cite journal|last1=Khalili|first1=Abdullah|last2=Soliman|first2=Abdel-Hamid|last3=Asaduzzaman|first3=Md|last4=Griffiths|first4=Alison|date=March 2020|title=Wi-Fi sensing: applications and challenges|journal=The Journal of Engineering|language=en|volume=2020|issue=3|pages=87–97|doi=10.1049/joe.2019.0790|issn=2051-3305|doi-access=free|arxiv=1901.00715}}</ref>