WHAT IS WIFI?
Wi-Fi, also spelled
Wifi or WiFi, is a popular technology that allows an electronic device to
exchange data or connect to the internet wirelessly using radio waves. The
Wi-Fi Alliance defines Wi-Fi as any "wireless local area network (WLAN)
products that are based on the Institute of Electrical and Electronics
Engineers' (IEEE) 802.11 standards".[1] However, since most modern WLANs
are based on these standards, the term "Wi-Fi" is used in general
English as a synonym for "WLAN". Only Wi-Fi products that complete
Wi-Fi Alliance interoperability certification testing successfully may use the
"Wi-Fi CERTIFIED" trademark.
A device that can use Wi-Fi (such as a personal computer, video-game console,
smartphone, digital camera, tablet or digital audio player) can connect to a
network resource such as the Internet via a wireless network access point. Such
an access point (or hotspot) has a range of about 20 meters (65 feet) indoors
and a greater range outdoors. Hotspot coverage can comprise an area as small as
a single room with walls that block radio waves or as large as many square
miles — this is achieved by using multiple overlapping access points
Wi-Fi can be less secure than wired connections (such as Ethernet) because an
intruder does not need a physical connection. Web pages that use SSL are secure
but unencrypted internet access can easily be detected by intruders. Because of
this, Wi-Fi has adopted various encryption technologies. The early encryption
WEP, proved easy to break. Higher quality protocols (WPA, WPA2) were added
later. An optional feature added in 2007, called Wi-Fi Protected Setup (WPS),
had a serious flaw that allowed an attacker to recover the router's
password.[2] The Wi-Fi Alliance has since updated its test plan and
certification program to ensure all newly certified devices resist attacks
INTERNET ACCESS
A Wi-Fi-enabled device
can connect to the Internet when within range of a wireless network which is
configured to permit this. The coverage of one or more (interconnected) access
points — called hotspots — can extend from an area as small as a few rooms to
as large as many square miles. Coverage in the larger area may require a group
of access points with overlapping coverage. Outdoor public Wi-Fi technology has
been used successfully in wireless mesh networks in London, UK.
Wi-Fi provides service in private homes, high street chains and independent
businesses, as well as in public spaces at Wi-Fi hotspots set up either
free-of-charge or commercially. Organizations and businesses, such as airports,
hotels, and restaurants, often provide free-use hotspots to attract customers.
Enthusiasts or authorities who wish to provide services or even to promote
business in selected areas sometimes provide free Wi-Fi access.
Routers that incorporate a digital subscriber line modem or a cable modem and a
Wi-Fi access point, often set up in homes and other buildings, provide Internet
access and internetworking to all devices connected to them, wirelessly or via
cable.
Similarly, there are
battery-powered routers that include a cellular mobile Internet radiomodem and
Wi-Fi access point. When subscribed to a cellular phone carrier, they allow
nearby Wi-Fi stations to access the Internet over 2G, 3G, or 4G networks. Many
smartphones have a built-in capability of this sort, including those based on
Android, Bada, iOS (iPhone), Windows Phone and Symbian, though carriers often
disable the feature, or charge a separate fee to enable it, especially for
customers with unlimited data plans. "Internet packs" provide
standalone facilities of this type as well, without use of a smartphone;
examples include the MiFi- and WiBro-branded devices. Some laptops that have a
cellular modem card can also act as mobile Internet Wi-Fi access points.
CITY-WIDE WIFI
In the early 2000s,
many cities around the world announced plans to construct city-wide Wi-Fi
networks. There are many successful examples; in 2004, Mysore became India's
first Wi-Fi-enabled city and second in the world after Jerusalem. A company
called WiFiyNet has set up hotspots in Mysore, covering the complete city and a
few nearby villages.[26]
In 2005, Sunnyvale,
California, became the first city in the United States to offer city-wide free
Wi-Fi.[27] Minneapolis has generated $1.2 million in profit annually for its
provider.[28]
In May 2010, London,
UK, Mayor Boris Johnson pledged to have London-wide Wi-Fi by 2012.[29] Several
boroughs including Westminster and Islington[30][31] already have extensive
outdoor Wi-Fi coverage.
Officials in South Korea's capital are 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 will grant leases
to KT, LG Telecom and SK Telecom. The companies will invest $44 million in the
project, which will be completed in 2015.[32]
CAMPUS-WIDE WIFI
In 2000, Drexel University in Philadelphia became the United States' first
major university to offer completely wireless Internet access across its entire
campus.[36] The Far Eastern University in Manila is the first university in the
Philippines to implement a campus-wide Wi-Fi coverage
WHAT IS WIFI?
Wi-Fi, also spelled
Wifi or WiFi, is a popular technology that allows an electronic device to
exchange data or connect to the internet wirelessly using radio waves. The
Wi-Fi Alliance defines Wi-Fi as any "wireless local area network (WLAN)
products that are based on the Institute of Electrical and Electronics
Engineers' (IEEE) 802.11 standards".[1] However, since most modern WLANs
are based on these standards, the term "Wi-Fi" is used in general
English as a synonym for "WLAN". Only Wi-Fi products that complete
Wi-Fi Alliance interoperability certification testing successfully may use the
"Wi-Fi CERTIFIED" trademark.
A device that can use Wi-Fi (such as a personal computer, video-game console,
smartphone, digital camera, tablet or digital audio player) can connect to a
network resource such as the Internet via a wireless network access point. Such
an access point (or hotspot) has a range of about 20 meters (65 feet) indoors
and a greater range outdoors. Hotspot coverage can comprise an area as small as
a single room with walls that block radio waves or as large as many square
miles — this is achieved by using multiple overlapping access points
Wi-Fi can be less secure than wired connections (such as Ethernet) because an
intruder does not need a physical connection. Web pages that use SSL are secure
but unencrypted internet access can easily be detected by intruders. Because of
this, Wi-Fi has adopted various encryption technologies. The early encryption
WEP, proved easy to break. Higher quality protocols (WPA, WPA2) were added
later. An optional feature added in 2007, called Wi-Fi Protected Setup (WPS),
had a serious flaw that allowed an attacker to recover the router's
password.[2] The Wi-Fi Alliance has since updated its test plan and
certification program to ensure all newly certified devices resist attacks
INTERNET ACCESS
Wi-Fi provides service in private homes, high street chains and independent
businesses, as well as in public spaces at Wi-Fi hotspots set up either
free-of-charge or commercially. Organizations and businesses, such as airports,
hotels, and restaurants, often provide free-use hotspots to attract customers.
Enthusiasts or authorities who wish to provide services or even to promote
business in selected areas sometimes provide free Wi-Fi access.
Routers that incorporate a digital subscriber line modem or a cable modem and a
Wi-Fi access point, often set up in homes and other buildings, provide Internet
access and internetworking to all devices connected to them, wirelessly or via
cable.
Similarly, there are
battery-powered routers that include a cellular mobile Internet radiomodem and
Wi-Fi access point. When subscribed to a cellular phone carrier, they allow
nearby Wi-Fi stations to access the Internet over 2G, 3G, or 4G networks. Many
smartphones have a built-in capability of this sort, including those based on
Android, Bada, iOS (iPhone), Windows Phone and Symbian, though carriers often
disable the feature, or charge a separate fee to enable it, especially for
customers with unlimited data plans. "Internet packs" provide
standalone facilities of this type as well, without use of a smartphone;
examples include the MiFi- and WiBro-branded devices. Some laptops that have a
cellular modem card can also act as mobile Internet Wi-Fi access points.
CITY-WIDE WIFI
In the early 2000s,
many cities around the world announced plans to construct city-wide Wi-Fi
networks. There are many successful examples; in 2004, Mysore became India's
first Wi-Fi-enabled city and second in the world after Jerusalem. A company
called WiFiyNet has set up hotspots in Mysore, covering the complete city and a
few nearby villages.[26]
In 2005, Sunnyvale,
California, became the first city in the United States to offer city-wide free
Wi-Fi.[27] Minneapolis has generated $1.2 million in profit annually for its
provider.[28]
In May 2010, London,
UK, Mayor Boris Johnson pledged to have London-wide Wi-Fi by 2012.[29] Several
boroughs including Westminster and Islington[30][31] already have extensive
outdoor Wi-Fi coverage.
CAMPUS-WIDE WIFI
Many traditional
college campuses in the United States provide at least partial wireless Wi-Fi
Internet 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 originated.[33][34][35] In Europe many universities
collaborate in providing Wi-Fi access to students and staff through the eduroam
international authentication infrastructure.
In 2000, Drexel University in Philadelphia became the United States' first
major university to offer completely wireless Internet access across its entire
campus.[36] The Far Eastern University in Manila is the first university in the
Philippines to implement a campus-wide Wi-Fi coverage
