- Wifi - Wikipedia
- family of wireless networking technologies, based on the IEEE 802.11 family of standards
- most commonly uses the 2.4 GHz UHF and 5 GHz SHF ISM radio bands which are subdivided into channels
- Wi-Fi's wavebands have relatively high absorption and work best for line-of-sight use
- using appropriate hardware, in 2019 speed up to 1 GHz was possible over Wi-Fi
- Wi-Fi 1 (802.11b) - 1 to 11 Mbit/s - 1999 - 2.4 GHz
- Wi-Fi 2 (802.11a) - 1.5 to 54 Mbit/s - 1999 - 5 GHz
- Wi-Fi 3 (802.11g) - 3–54 Mbit/s - 2003 - 2.4 GHz
- Wi-Fi 4 (802.11n) - 72–600 Mbit/s - 2009 - 2.4/5 GHz
- Wi-Fi 5 (802.11ac) - 433–6933 Mbit/s - 2014 - 5 GHz
- Wi-Fi 6 (802.11ax) - 600–9608 Mbit/s - 2019 - 2.4/5 GHz and 1–6 GHz ISM
- different versions use different modulation, 802.11b uses DSSS on a single carrier,
whereas 802.11a, Wi-Fi 4, 5 and 6 use multiple carriers on slightly different frequencies within the channel (OFDM)
- Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is the access scheme
- modes include infrastructure mode, the most common mode used, where all communications goes through a base station, and ad-hoc and Wi-Fi direct modes
- WEP - initially Wired Equivalent Privacy (WEP) encryption protected against snooping but it is no longer considered secure since
e.g. Aircrack-ng can quickly recover WEP encryption keys
- WPA - the Wi-Fi Alliance approved Wi-Fi Protected Access (WPA) which uses TKIP.
WPA was specifically designed to work with older equipment usually through a firmware upgrade.
WPA2 replaced WPA in 2004. It uses AES. In 2017, a flaw in the WPA2 protocol was discovered, allowing a key replay attack,
known as KRACK.
- WPS - Wi-Fi Protected Setup was introduced in 2007, but it contained a flaw which let WPA and WPA2 security be
bypassed, and effectively broken in many situations. The only remedy as of late 2011 was to turn WPS off.
WPS works with a dedicated WPS button, or a WPS PIN (typically printed on the access point). Tools such as Reaver
try all PINs as attack.
- WPA3 was announced in 2018
- Wi-Fi.org - the Wi-Fi Alliance of manufacturers
- Supplicant is the IEEE 802.1X/WPA component used in the client. Implements key negotiation with a WPA Authenticator and it controls the roaming and IEEE 802.11 authentication/association of the wlan driver.
- wpa_supplicant - a WPA Supplicant for Linux, BSD, Mac OS X, and Windows with support for WPA and WPA2 (IEEE 802.11i / RSN).
- Open1X - free, open source 802.1X/WPA/WPA2/IEEE802.11i implementation - XSupplicant - apparently stalled in 2010.
- MobiusConsulting - RR's brother-in-law
PAN - Personal Area Networks
Also: Bluetooth Low Energy - BLE
Wireless Linux - refer also to the Linux section
Zigbee - wireless home control