IEEE 802.11

802.11802.11b/g/n802.11b/g802.11a/b/g/n802.11a/b/g/n/ac802.11 b/g/n802.11b802.11 a/b/g/n802.11 b/g802.11g
IEEE 802.11 is part of the IEEE 802 set of LAN protocols, and specifies the set of media access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) Wi-Fi computer communication in various frequencies, including but not limited to 2.4, 5, and 60 GHz frequency bands.wikipedia
797 Related Articles

Wi-Fi

WiFiwireless internetwireless
IEEE 802.11 is part of the IEEE 802 set of LAN protocols, and specifies the set of media access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) Wi-Fi computer communication in various frequencies, including but not limited to 2.4, 5, and 60 GHz frequency bands. In 1999, the Wi-Fi Alliance was formed as a trade association to hold the Wi-Fi trademark under which most products are sold.
Wi-Fi is technology for radio wireless local area networking of devices based on the IEEE 802.11 standards.

Wireless LAN

WLANwireless local area networkwireless
IEEE 802.11 is part of the IEEE 802 set of LAN protocols, and specifies the set of media access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) Wi-Fi computer communication in various frequencies, including but not limited to 2.4, 5, and 60 GHz frequency bands.
Most modern WLANs are based on IEEE 802.11 standards and are marketed under the Wi-Fi brand name.

Ethernet

wiredJabbernetworking
The protocols are typically used in conjunction with IEEE 802.2, and are designed to interwork seamlessly with Ethernet, and are very often used to carry Internet Protocol traffic.
The primary alternative for some uses of contemporary LANs is Wi-Fi, a wireless protocol standardized as IEEE 802.11.

List of WLAN channels

2.4 GHzwireless channel2.4
802.11a uses the 5 GHz U-NII band, which, for much of the world, offers at least 23 non-overlapping 20 MHz-wide channels rather than the 2.4 GHz ISM frequency band offering only three non-overlapping 20 MHz-wide channels, where other adjacent channels overlap—see list of WLAN channels.
Wireless local area network channels are frequently accessed using IEEE 802.11 protocols are sold mostly under the trademark WiFi.

Wi-Fi Alliance

Wi-Fi EasyMeshWireless Ethernet Compatibility Alliance
In 1999, the Wi-Fi Alliance was formed as a trade association to hold the Wi-Fi trademark under which most products are sold.
Not every IEEE 802.11-compliant device is submitted for certification to the Wi-Fi Alliance, sometimes because of costs associated with the certification process.

WaveLAN

Classic WaveLAN
The first wireless products were brought to the market under the name WaveLAN with raw data rates of 1 Mbit/s and 2 Mbit/s.
Pre-IEEE 802.11 WaveLAN, also called Classic WaveLAN

List of 2.4 GHz radio use

2.4 GHzElectromagnetic interference at 2.4 GHzinterference in the 2.4 GHz band
Because of this choice of frequency band, 802.11b/g/n equipment may occasionally suffer interference in the 2.4 GHz band from microwave ovens, cordless telephones, and Bluetooth devices etc. 802.11b and 802.11g control their interference and susceptibility to interference by using direct-sequence spread spectrum (DSSS) and orthogonal frequency-division multiplexing (OFDM) signaling methods, respectively.
Wi-Fi is technology for radio wireless local area networking of devices based on the IEEE 802.11 standards.

IEEE 802

802802 Committee802 standards
IEEE 802.11 is part of the IEEE 802 set of LAN protocols, and specifies the set of media access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) Wi-Fi computer communication in various frequencies, including but not limited to 2.4, 5, and 60 GHz frequency bands.

IEEE 802.2

802.2LSAP
The protocols are typically used in conjunction with IEEE 802.2, and are designed to interwork seamlessly with Ethernet, and are very often used to carry Internet Protocol traffic.
Conversely, the LLC uses the services of the media access control (MAC), which is dependent on the specific transmission medium (Ethernet, Token Ring, FDDI, 802.11, etc.).

Carrier-sense multiple access with collision avoidance

CSMA/CAcarrier sense multiple access with collision avoidancecollision avoidance
The 802.11 protocol family employ carrier-sense multiple access with collision avoidance whereby equipment listens to a channel for other users (including non 802.11 users) before transmitting each packet.
Request to Send/Clear to Send (RTS/CTS) may optionally be used at this point to mediate access to the shared medium. This goes some way to alleviating the problem of hidden nodes because, for instance, in a wireless network, the Access Point only issues a Clear to Send to one node at a time. However, wireless 802.11 implementations do not typically implement RTS/CTS for all transmissions; they may turn it off completely, or at least not use it for small packets (the overhead of RTS, CTS and transmission is too great for small data transfers).

IEEE 802.11b-1999

b802.11bIEEE 802.11b
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
IEEE 802.11b-1999 or 802.11b, is an amendment to the IEEE 802.11 wireless networking specification that extends throughput up to 11 Mbit/s using the same 2.4GHz band.

IEEE 802.11g-2003

g802.11b/g802.11g
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
IEEE 802.11g-2003 or 802.11g is an amendment to the IEEE 802.11 specification that extended throughput to up to 54 Mbit/s using the same 2.4 GHz band as 802.11b.

IEEE 802.11i-2004

802.11iWPA2i
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
IEEE 802.11i-2004, or 802.11i for short, is an amendment to the original IEEE 802.11, implemented as Wi-Fi Protected Access II (WPA2).

IEEE 802.11d-2001

d
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
IEEE 802.11d-2001 is an amendment to the IEEE 802.11 specification that adds support for "additional regulatory domains".

IEEE 802.11a-1999

a802.11a802.11a/b/g
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
802.11 is a set of IEEE standards that govern wireless networking transmission methods.

IEEE 802.11h-2003

802.11hh
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
IEEE 802.11h-2003, or just 802.11h, refers to the amendment added to the IEEE 802.11 standard for Spectrum and Transmit Power Management Extensions.

ISM band

ISM2.4 GHz13.56 MHz
802.11b and 802.11g use the 2.4 GHz ISM band, operating in the United States under Part 15 of the U.S. Federal Communications Commission Rules and Regulations; 802.11n can also use that band.
The IEEE 802.11 wireless networking protocols, the standards on which almost all wireless systems are based, use the ISM bands.

IEEE 802.11r-2008

802.11rfast roamingr
REVmb or 802.11mb, as it was called, created a single document that merged ten amendments (802.11k, r, y, n, w, p, z, v, u, s) with the 2007 base standard.
IEEE 802.11r-2008 or fast BSS transition (FT), also called fast roaming, is an amendment to the IEEE 802.11 standard to permit continuous connectivity aboard wireless devices in motion, with fast and secure handoffs from one base station to another managed in a seamless manner.

IEEE 802.11j-2004

j
REVma or 802.11ma, as it was called, created a single document that merged 8 amendments (802.11a, b, d, e, g, h, i, j) with the base standard.
802.11j-2004 or 802.11j is an amendment to the IEEE 802.11 standard designed specially for Japanese market.

IEEE 802.11y-2008

3.63650–3700 MHzy
REVmb or 802.11mb, as it was called, created a single document that merged ten amendments (802.11k, r, y, n, w, p, z, v, u, s) with the 2007 base standard.
IEEE 802.11y-2008 is an amendment to the IEEE 802.11-2007 standard that enables high powered data transfer equipment to operate using the 802.11a protocol on a co-primary basis in the 3650 to 3700 MHz band in the United States, except when near a grandfathered satellite earth station.

Direct-sequence spread spectrum

Direct Sequence Spread SpectrumDSSSdirect sequence
Because of this choice of frequency band, 802.11b/g/n equipment may occasionally suffer interference in the 2.4 GHz band from microwave ovens, cordless telephones, and Bluetooth devices etc. 802.11b and 802.11g control their interference and susceptibility to interference by using direct-sequence spread spectrum (DSSS) and orthogonal frequency-division multiplexing (OFDM) signaling methods, respectively.
Some practical and effective uses of DSSS include the Code Division Multiple Access (CDMA) channel access method and the IEEE 802.11b specification used in Wi-Fi networks.

IEEE 802.11p

802.11pWAVE5.9 GHz band
REVmb or 802.11mb, as it was called, created a single document that merged ten amendments (802.11k, r, y, n, w, p, z, v, u, s) with the 2007 base standard.
IEEE 802.11p is an approved amendment to the IEEE 802.11 standard to add wireless access in vehicular environments (WAVE), a vehicular communication system.

IEEE 802.11s

802.11ss
REVmb or 802.11mb, as it was called, created a single document that merged ten amendments (802.11k, r, y, n, w, p, z, v, u, s) with the 2007 base standard.
IEEE 802.11s is Wireless LAN standard and an IEEE 802.11 amendment for mesh networking, defining how wireless devices can interconnect to create a WLAN mesh network, which may be used for relatively fixed (not mobile) topologies and wireless ad hoc networks.

Bluetooth

Bluetooth 2.1 + EDR4.0Bluetooth 2.1+EDR
Because of this choice of frequency band, 802.11b/g/n equipment may occasionally suffer interference in the 2.4 GHz band from microwave ovens, cordless telephones, and Bluetooth devices etc. 802.11b and 802.11g control their interference and susceptibility to interference by using direct-sequence spread spectrum (DSSS) and orthogonal frequency-division multiplexing (OFDM) signaling methods, respectively.
Bluetooth and Wi-Fi (Wi-Fi is the brand name for products using IEEE 802.11 standards) have some similar applications: setting up networks, printing, or transferring files.

IEEE 802.11u

802.11uu
REVmb or 802.11mb, as it was called, created a single document that merged ten amendments (802.11k, r, y, n, w, p, z, v, u, s) with the 2007 base standard.
IEEE 802.11u-2011 is an amendment to the IEEE 802.11-2007 standard to add features that improve interworking with external networks.