Wi-Fi or WiFi is a technology that allows
electronic devices to connect to a wireless LAN (WLAN), mainly using
the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SHF ISM radio
bands. A WLAN is usually password protected, but may be open, which allows any
device within its range to access the resources of the WLAN network.
The Wi-Fi Alliance defines Wi-Fi as any
"wireless local area network" (WLAN) product based on the Institute
of Electrical and Electronics Engineers' (IEEE) 802.11 standards."Wi-Fi"
is a trademark of the Wi-Fi Alliance. The "Wi-Fi Certified" trademark
can only be used by Wi-Fi products that successfully complete Wi-Fi
Alliance interoperability certification testing.
Devices that can use Wi-Fi technology include personal
computers, video-game consoles, smartphones, digital cameras, tablet
computers, digital audio players and modern printers. Wi-Fi compatible devices
can connect to the Internet via a WLAN network and a wireless access point.
Such an access point (or hotspot) has a range of about 20 meters (66 feet)
indoors and a greater 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
achieved by using multiple overlapping access points.
Depiction of a device sending information wirelessly to
another device, both connected to the local network, in order to print a
document.
Wi-Fi is less secure than wired connections, such
as Ethernet, precisely because an intruder does not need a physical
connection. Web pages that use TLS 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. The
Wi-Fi Alliance has since updated its test plan and certification program to
ensure all newly certified devices resist attacks.
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