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.
A wireless network is a computer network that uses wireless data connections between network nodes.
In telecommunications and computer networks, a channel access method or multiple access method allows more than two terminals connected to the same transmission medium to transmit over it and to share its capacity. Examples of shared physical media are wireless networks, bus networks, ring networks and point-to-point links operating in half-duplex mode.
IEEE 802.11e-2005 or 802.11e is an approved amendment to the IEEE 802.11 standard that defines a set of quality of service (QoS) enhancements for wireless LAN applications through modifications to the media access control (MAC) layer. The standard is considered of critical importance for delay-sensitive applications, such as Voice over Wireless LAN and streaming multimedia. The amendment has been incorporated into the published IEEE 802.11-2007 standard.
Distributed coordination function (DCF) is the fundamental medium access control (MAC) technique of the IEEE 802.11-based WLAN standard. DCF employs a carrier-sense multiple access with collision avoidance (CSMA/CA) with binary exponential backoff algorithm.
A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. It is also a form of wireless ad hoc network.
Voice over wireless LAN is the use of a wireless broadband network according to the IEEE 802.11 standards for the purpose of vocal conversation. In essence, it is voice over IP (VoIP) over a Wi-Fi network. In most cases, the Wi-Fi network and voice components supporting the voice system are privately owned.
Point coordination function (PCF) is a media access control (MAC) technique used in IEEE 802.11 based WLANs, including Wi-Fi. It resides in a point coordinator also known as access point (AP), to coordinate the communication within the network. The AP waits for PIFS duration rather than DIFS duration to grasp the channel. PIFS is less than DIFS duration and hence the point coordinator always has the priority to access the channel.
IEEE 802.11d-2001 is an amendment to the IEEE 802.11 specification that adds support for "additional regulatory domains". This support includes the addition of a country information element to beacons, probe requests, and probe responses. The country information elements simplifies the creation of 802.11 wireless access points and client devices that meet the different regulations enforced in various parts of the world. The amendment has been incorporated into the published IEEE 802.11-2012 standard.
IEEE 802.11v is an amendment to the IEEE 802.11 standard to allow configuration of client devices while connected to wireless networks. It was published as 802.11v-2011 and later incorporated into 802.11-2012
Qualcomm Atheros is a developer of semiconductors for network communications, particularly wireless chipsets. Founded under the name T-Span Systems in 1998 by experts in signal processing and VLSI design from Stanford University, the University of California, Berkeley and private industry. The company was renamed Atheros Communications in 2000 and it completed an initial public offering in February 2004 trading on NASDAQ under the symbol ATHR.
A wide variety of different wireless data technologies exist, some in direct competition with one another, others designed for specific applications. Wireless technologies can be evaluated by a variety of different metrics of which some are described in this entry.
In May 1991, the first Institute of Electrical and Electronics Engineers (IEEE) workshop on Wireless LANs was held at the Worcester Polytechnic Institute. The workshop was scheduled in coordination with a meeting of the IEEE 802.11 Wireless Access Methods and Physical Layer Standardization Committee for Wireless LAN, also held in Worcester. This workshop was the first organized by the IEEE to address issues associated with wireless LANs. Its aim was to increase the awareness of then-current developments and future direction in the WLAN field, and to foster interaction among researchers, spectrum regulators, standardization organizations, leading manufacturers and end users.
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. A related amendment was incorporated into the IEEE 802.11-2007 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. This specification under the marketing name of Wi-Fi has been implemented all over the world. The 802.11g protocol is now Clause 19 of the published IEEE 802.11-2007 standard, and Clause 19 of the published IEEE 802.11-2012 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 topologies and wireless ad hoc networks. The IEEE 802.11s working group draws upon volunteers from university and industry to provide specifications and possible design solutions for wireless mesh networking. As a standard, the document was iterated and revised many times prior to finalization.
IEEE 802.11k-2008 is an amendment to IEEE 802.11-2007 standard for radio resource management. It defines and exposes radio and network information to facilitate the management and maintenance of a mobile Wireless LAN. IEEE 802.11k was incorporated in IEEE Std 802.11-2012; see IEEE 802.11.
IEEE 802.11ad is an amendment to the IEEE 802.11 wireless networking standard, developed to provide a Multiple Gigabit Wireless System (MGWS) standard at 60 GHz frequency, and is a networking standard for WiGig networks. Because it uses the V band of millimeter wave (mmW) frequency, the range of IEEE 802.11ad communication would be rather limited compared to other conventional Wi-Fi systems. However, the high frequency allows it to use more bandwidth which in turn enables the transmission of data at high data rates up to multiple gigabits per second, enabling usage scenarios like transmission of uncompressed UHD video over the wireless network.
IEEE 802.11ah is a wireless networking protocol published in 2017 to be called Wi-Fi HaLow as an amendment of the IEEE 802.11-2007 wireless networking standard. It uses 900 MHz license exempt bands to provide extended range Wi-Fi networks, compared to conventional Wi-Fi networks operating in the 2.4 GHz and 5 GHz bands. It also benefits from lower energy consumption, allowing the creation of large groups of stations or sensors that cooperate to share signals, supporting the concept of the Internet of Things (IoT). The protocol's low power consumption competes with Bluetooth and has the added benefit of higher data rates and wider coverage range.
IEEE 802.11af, also referred to as White-Fi and Super Wi-Fi, is a wireless computer networking standard in the 802.11 family, that allows wireless local area network (WLAN) operation in TV white space spectrum in the VHF and UHF bands between 54 and 790 MHz. The standard was approved in February 2014. Cognitive radio technology is used to transmit on unused portions of TV channel band allocations, with the standard taking measures to limit interference for primary users, such as analog TV, digital TV, and wireless microphones.
