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73-752: OWE is an extension to IEEE 802.11 . it is an encryption technique similar to that of Simultaneous Authentication of Equals (SAE) and is specified by Internet Engineering Task Force (IETF) in RFC 8110 with devices certified as Wi-Fi Certified Enhanced Open by the Wi-Fi Alliance . With a network without a password, each WPA3 device that connects to it will still have its connection encrypted, OWE does encryption, not authentication, Evil twin (wireless networks) attack protection requires either WPA3-Personal or WPA3-Enterprise. Unlike conventional Wi-Fi, it provides "Individualized Data Protection" such that data traffic between

146-641: A 1985 ruling by the U.S. Federal Communications Commission that released the ISM band for unlicensed use. In 1991 NCR Corporation / AT&T (now Nokia Labs and LSI Corporation ) invented a precursor to 802.11 in Nieuwegein, the Netherlands. The inventors initially intended to use the technology for cashier systems. 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. Vic Hayes , who held

219-470: A WLAN system operating at sub-1 GHz license-exempt bands. Due to the favorable propagation characteristics of the low-frequency spectra, 802.11ah can provide improved transmission range compared with the conventional 802.11 WLANs operating in the 2.4 GHz and 5 GHz bands. 802.11ah can be used for various purposes including large-scale sensor networks, extended-range hotspots, and outdoor Wi-Fi for cellular WAN carrier traffic offloading, whereas

292-459: A channel for other users (including non 802.11 users) before transmitting each frame (some use the term "packet", which may be ambiguous: "frame" is more technically correct). 802.11-1997 was the first wireless networking standard in the family, but 802.11b was the first widely accepted one, followed by 802.11a , 802.11g , 802.11n , 802.11ac , and 802.11ax . Other standards in the family (c–f, h, j) are service amendments that are used to extend

365-448: A client and access point is "individualized". Other clients can still sniff and record this traffic, but they can't decrypt it. "OWE is a means of adding encryption to open networks...OWE only protects against passive attacks." Opportunistic Wireless Encryption is a Wi-Fi Enhanced Open authentication mode, as a part of Wi-Fi Protected Access 3 . OWE performs an unauthenticated Diffie–Hellman (DH) key exchange at association time. For

438-510: A communications system or integrated into the communication system's central processing unit . Where channel access methods are used in point-to-multipoint networks (such as cellular networks ) for dividing forward and reverse communication channels on the same physical communications medium, they are known as duplexing methods. Time-division duplexing ( TDD ) is the application of time-division multiplexing to separate outward and return signals. It emulates full-duplex communication over

511-426: A half-duplex communication link. Time-division duplexing is flexible in the case where there is asymmetry of the uplink and downlink data rates or utilization. As the amount of uplink data increases, more communication capacity can be dynamically allocated, and as the traffic load becomes lighter, capacity can be taken away. The same applies in the downlink direction. The transmit/receive transition gap (TTG)

584-669: A half-duplex system. For example, station A on one end of the data link could be allowed to transmit for exactly one second, then station B on the other end could be allowed to transmit for exactly one second, and then the cycle repeats. In this scheme, the channel is never left idle. In half-duplex systems, if more than one party transmits at the same time, a collision occurs, resulting in lost or distorted messages. A full-duplex ( FDX ) system allows communication in both directions, and, unlike half-duplex, allows this to happen simultaneously. Land-line telephone networks are full-duplex since they allow both callers to speak and be heard at

657-431: A maximum raw data rate of 11 Mbit/s (Megabits per second) and uses the same media access method defined in the original standard. 802.11b products appeared on the market in early 2000, since 802.11b is a direct extension of the modulation technique defined in the original standard. The dramatic increase in throughput of 802.11b (compared to the original standard) along with simultaneous substantial price reductions led to

730-426: A result, in the marketplace, each revision tends to become its own standard. 802.11x is a shorthand for "any version of 802.11", to avoid confusion with "802.11" used specifically for the original 1997 version . IEEE 802.11 uses various frequencies including, but not limited to, 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz frequency bands. Although IEEE 802.11 specifications list channels that might be used,

803-453: A reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service ; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces

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876-524: A satellite positioning system such as GPS , and use the Internet to query a geolocation database (GDB) provided by a regional regulatory agency to discover what frequency channels are available for use at a given time and position. The physical layer uses OFDM and is based on 802.11ac. The propagation path loss as well as the attenuation by materials such as brick and concrete is lower in the UHF and VHF bands than in

949-696: A significant advantage. However, this high carrier frequency also brings a disadvantage: the effective overall range of 802.11a is less than that of 802.11b/g. In theory, 802.11a signals are absorbed more readily by walls and other solid objects in their path due to their smaller wavelength, and, as a result, cannot penetrate as far as those of 802.11b. In practice, 802.11b typically has a higher range at low speeds (802.11b will reduce speed to 5.5 Mbit/s or even 1 Mbit/s at low signal strengths). 802.11a also suffers from interference, but locally there may be fewer signals to interfere with, resulting in less interference and better throughput. The 802.11b standard has

1022-444: A single mobile adapter card or access point. Details of making b and g work well together occupied much of the lingering technical process; in an 802.11g network, however, the activity of an 802.11b participant will reduce the data rate of the overall 802.11g network. Like 802.11b, 802.11g devices also suffer interference from other products operating in the 2.4 GHz band, for example, wireless keyboards. In 2003, task group TGma

1095-405: A third modulation standard was ratified: 802.11g. This works in the 2.4 GHz band (like 802.11b), but uses the same OFDM based transmission scheme as 802.11a. It operates at a maximum physical layer bit rate of 54 Mbit/s exclusive of forward error correction codes, or about 22 Mbit/s average throughput. 802.11g hardware is fully backward compatible with 802.11b hardware, and therefore

1168-652: Is 26.7 Mbit/s for 6 and 7 MHz channels, and 35.6 Mbit/s for 8 MHz channels. With four spatial streams and four bonded channels, the maximum data rate is 426.7 Mbit/s for 6 and 7 MHz channels and 568.9 Mbit/s for 8 MHz channels. IEEE 802.11-2016 which was known as IEEE 802.11 REVmc, is a revision based on IEEE 802.11-2012, incorporating 5 amendments ( 11ae , 11aa , 11ad , 11ac , 11af ). In addition, existing MAC and PHY functions have been enhanced and obsolete features were removed or marked for removal. Some clauses and annexes have been renumbered. IEEE 802.11ah, published in 2017, defines

1241-496: Is 300–500 m. IEEE 802.11ba Wake-up Radio (WUR) Operation is an amendment to the IEEE 802.11 standard that enables energy-efficient operation for data reception without increasing latency. The target active power consumption to receive a WUR packet is less than 1 milliwatt and supports data rates of 62.5 kbit/s and 250 kbit/s. The WUR PHY uses MC-OOK (multicarrier OOK ) to achieve extremely low power consumption. IEEE 802.11bb

1314-475: Is a stub . You can help Misplaced Pages by expanding it . IEEE 802.11 IEEE 802.11 is part of the IEEE 802 set of local area network (LAN) technical standards , and specifies the set of medium access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) computer communication. The standard and amendments provide the basis for wireless network products using

1387-407: Is a walkie-talkie , a two-way radio that has a push-to-talk button. When the local user wants to speak to the remote person, they push this button, which turns on the transmitter and turns off the receiver, preventing them from hearing the remote person while talking. To listen to the remote person, they release the button, which turns on the receiver and turns off the transmitter. This terminology

1460-583: Is a networking protocol standard in the IEEE 802.11 set of protocols that uses infrared light for communications. IEEE 802.11be Extremely High Throughput (EHT) is the potential next amendment to the 802.11 IEEE standard, and will likely be designated as Wi-Fi 7 . It will build upon 802.11ax, focusing on WLAN indoor and outdoor operation with stationary and pedestrian speeds in the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. Across all variations of 802.11, maximum achievable throughputs are given either based on measurements under ideal conditions or in

1533-405: Is a revision based on IEEE 802.11-2016 incorporating 5 amendments ( 11ai , 11ah , 11aj , 11ak , 11aq ). In addition, existing MAC and PHY functions have been enhanced and obsolete features were removed or marked for removal. Some clauses and annexes have been added. IEEE 802.11ax is the successor to 802.11ac, marketed as Wi-Fi 6 (2.4 GHz and 5 GHz) and Wi-Fi 6E (6 GHz) by

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1606-432: Is a signal-processing operation that subtracts the far-end signal from the microphone signal before it is sent back over the network. Echo cancellation is important technology allowing modems to achieve good full-duplex performance. The V.32 , V.34 , V.56 , and V.90 modem standards require echo cancellation. Echo cancelers are available as both software and hardware implementations. They can be independent components in

1679-434: Is an advantage over the 2.4-GHz, ISM-frequency band, which offers only three non-overlapping, 20-MHz-wide channels where other adjacent channels overlap (see: list of WLAN channels ). Better or worse performance with higher or lower frequencies (channels) may be realized, depending on the environment. 802.11n and 802.11ax can use either the 2.4 GHz or 5 GHz band; 802.11ac uses only the 5 GHz band. The segment of

1752-472: Is an amendment that defines a new physical layer for 802.11 networks to operate in the 60 GHz millimeter wave spectrum. This frequency band has significantly different propagation characteristics than the 2.4 GHz and 5 GHz bands where Wi-Fi networks operate. Products implementing the 802.11ad standard are being brought to market under the WiGig brand name, with a certification program developed by

1825-563: Is an amendment, approved in February 2014, that allows WLAN operation in TV white space spectrum in the VHF and UHF bands between 54 and 790 MHz. It uses cognitive radio technology to transmit on unused TV channels, with the standard taking measures to limit interference for primary users, such as analog TV, digital TV, and wireless microphones. Access points and stations determine their position using

1898-452: Is encumbered with legacy issues that reduce throughput by ~21% when compared to 802.11a. The then-proposed 802.11g standard was rapidly adopted in the market starting in January 2003, well before ratification, due to the desire for higher data rates as well as reductions in manufacturing costs. By summer 2003, most dual-band 802.11a/b products became dual-band/tri-mode, supporting a and b/g in

1971-411: Is equivalent to cellular technology applied into Wi-Fi . The IEEE 802.11ax‑2021 standard was approved on February 9, 2021. IEEE 802.11ay is a standard that is being developed, also called EDMG: Enhanced Directional MultiGigabit PHY. It is an amendment that defines a new physical layer for 802.11 networks to operate in the 60 GHz millimeter wave spectrum. It will be an extension of

2044-443: Is for sending packets. Other Ethernet variants, such as 1000BASE-T use the same channels in each direction simultaneously. In any case, with full-duplex operation, the cable itself becomes a collision-free environment and doubles the maximum total transmission capacity supported by each Ethernet connection. Full-duplex has also several benefits over the use of half-duplex. Since there is only one transmitter on each twisted pair there

2117-402: Is frequently used in ham radio operation, where an operator is attempting to use a repeater station. The repeater station must be able to send and receive a transmission at the same time and does so by slightly altering the frequency at which it sends and receives. This mode of operation is referred to as duplex mode or offset mode . Uplink and downlink sub-bands are said to be separated by

2190-414: Is no contention and no collisions so time is not wasted by having to wait or retransmit frames. Full transmission capacity is available in both directions because the send and receive functions are separate. Some computer-based systems of the 1960s and 1970s required full-duplex facilities, even for half-duplex operation, since their poll-and-response schemes could not tolerate the slight delays in reversing

2263-447: Is not completely standardized between defining organizations, and in radio communication some sources classify this mode as simplex . Typically, once one party begins a transmission, the other party on the channel must wait for the transmission to complete, before replying. An example of a half-duplex system is a two-party system such as a walkie-talkie , wherein one must say "over" or another previously designated keyword to indicate

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2336-404: Is not completely standardized, and some sources define this mode as simplex . Systems that do not need duplex capability may instead use simplex communication , in which one device transmits and the others can only listen. Examples are broadcast radio and television, garage door openers , baby monitors , wireless microphones , and surveillance cameras . In these devices, the communication

2409-408: Is only in one direction. Simplex communication is a communication channel that sends information in one direction only. The International Telecommunication Union definition is a communications channel that operates in one direction at a time, but that may be reversible; this is termed half duplex in other contexts. For example, in TV and radio broadcasting , information flows only from

2482-525: Is shared alternately between the two directions. For example, a walkie-talkie or a DECT phone or so-called TDD 4G or 5G phones requires only a single frequency for bidirectional communication, while a cell phone in the so-called FDD mode is a full-duplex device, and generally requires two frequencies to carry the two simultaneous voice channels, one in each direction. In automatic communications systems such as two-way data-links, time-division multiplexing can be used for time allocations for communications in

2555-453: Is that it makes radio planning easier and more efficient since base stations do not hear each other (as they transmit and receive in different sub-bands) and therefore will normally not interfere with each other. Conversely, with time-division duplexing systems, care must be taken to keep guard times between neighboring base stations (which decreases spectral efficiency ) or to synchronize base stations, so that they will transmit and receive at

2628-402: Is the gap (time) between a downlink burst and the subsequent uplink burst. Similarly, the receive/transmit transition gap (RTG) is the gap between an uplink burst and the subsequent downlink burst. Examples of time-division duplexing systems include: Frequency-division duplexing ( FDD ) means that the transmitter and receiver operate using different carrier frequencies . The method

2701-500: The Industrial Scientific Medical frequency band at 2.4 GHz. Some earlier WLAN technologies used lower frequencies, such as the U.S. 900 MHz ISM band. Legacy 802.11 with direct-sequence spread spectrum was rapidly supplanted and popularized by 802.11b. 802.11a, published in 1999, uses the same data link layer protocol and frame format as the original standard, but an OFDM based air interface (physical layer)

2774-472: The Institute of Electrical and Electronics Engineers (IEEE) LAN/ MAN Standards Committee (IEEE 802). The base version of the standard was released in 1997 and has had subsequent amendments. While each amendment is officially revoked when it is incorporated in the latest version of the standard, the corporate world tends to market to the revisions because they concisely denote the capabilities of their products. As

2847-522: The Wi-Fi brand and are the world's most widely used wireless computer networking standards. IEEE 802.11 is used in most home and office networks to allow laptops, printers, smartphones, and other devices to communicate with each other and access the Internet without connecting wires. IEEE 802.11 is also a basis for vehicle-based communication networks with IEEE 802.11p . The standards are created and maintained by

2920-406: The Wi-Fi Alliance . It is also known as High Efficiency Wi-Fi , for the overall improvements to Wi-Fi 6 clients in dense environments . For an individual client, the maximum improvement in data rate ( PHY speed) against the predecessor (802.11ac) is only 39% (for comparison, this improvement was nearly 500% for the predecessors). Yet, even with this comparatively minor 39% figure, the goal

2993-551: The frequency offset . Frequency-division duplex systems can extend their range by using sets of simple repeater stations because the communications transmitted on any single frequency always travel in the same direction. Frequency-division duplexing can be efficient in the case of symmetric traffic. In this case, time-division duplexing tends to waste bandwidth during the switch-over from transmitting to receiving, has greater inherent latency , and may require more complex circuitry . Another advantage of frequency-division duplexing

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3066-546: The radio frequency spectrum used by 802.11 varies between countries. In the US, 802.11a and 802.11g devices may be operated without a license, as allowed in Part 15 of the FCC Rules and Regulations. Frequencies used by channels one through six of 802.11b and 802.11g fall within the 2.4 GHz amateur radio band. Licensed amateur radio operators may operate 802.11b/g devices under Part 97 of

3139-409: The 2.4 GHz and 5 GHz bands, which increases the possible range. The frequency channels are 6 to 8 MHz wide, depending on the regulatory domain. Up to four channels may be bonded in either one or two contiguous blocks. MIMO operation is possible with up to four streams used for either space–time block code (STBC) or multi-user (MU) operation. The achievable data rate per spatial stream

3212-446: The 2.4-GHz band from microwave ovens , cordless telephones , and Bluetooth devices. 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. 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. This

3285-405: The 60 GHz band. Alternatively known as China Millimeter Wave (CMMW). IEEE 802.11aq is an amendment to the 802.11 standard that will enable pre-association discovery of services. This extends some of the mechanisms in 802.11u that enabled device discovery to discover further the services running on a device, or provided by a network. IEEE 802.11-2020, which was known as IEEE 802.11 REVmd,

3358-412: The FCC Rules and Regulations, allowing increased power output but not commercial content or encryption. In 2018, the Wi-Fi Alliance began using a consumer-friendly generation numbering scheme for the publicly used 802.11 protocols. Wi-Fi generations 1–8 use the 802.11b, 802.11a, 802.11g, 802.11n, 802.11ac, 802.11ax, 802.11be and 802.11bn protocols, in that order. 802.11 technology has its origins in

3431-597: The Wi-Fi Alliance. The peak transmission rate of 802.11ad is 7 Gbit/s. IEEE 802.11ad is a protocol used for very high data rates (about 8 Gbit/s) and for short range communication (about 1–10 meters). TP-Link announced the world's first 802.11ad router in January 2016. The WiGig standard is not too well known, although it was announced in 2009 and added to the IEEE 802.11 family in December 2012. IEEE 802.11af, also referred to as "White-Fi" and " Super Wi-Fi ",

3504-633: The alliance started certifying Wave 1 802.11ac products shipped by manufacturers, based on the IEEE 802.11ac Draft 3.0 (the IEEE standard was not finalized until later that year). In 2016 Wi-Fi Alliance introduced the Wave 2 certification, to provide higher bandwidth and capacity than Wave 1 products. Wave 2 products include additional features like MU-MIMO, 160 MHz channel width support, support for more 5 GHz channels, and four spatial streams (with four antennas; compared to three in Wave 1 and 802.11n, and eight in IEEE's 802.11ax specification). IEEE 802.11ad

3577-543: The allowed radio frequency spectrum availability varies significantly by regulatory domain. 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 802.11 family consists of a series of half-duplex over-the-air modulation techniques that use the same basic protocol. The 802.11 protocol family employs carrier-sense multiple access with collision avoidance (CSMA/CA) whereby equipment listens to

3650-452: The amendment, and it was published in October 2009. Prior to the final ratification, enterprises were already migrating to 802.11n networks based on the Wi-Fi Alliance's certification of products conforming to a 2007 draft of the 802.11n proposal. In May 2007, task group TGmb was authorized to "roll up" many of the amendments to the 2007 version of the 802.11 standard. REVmb or 802.11mb, as it

3723-472: The available bandwidth is relatively narrow. The protocol intends consumption to be competitive with low-power Bluetooth , at a much wider range. IEEE 802.11ai is an amendment to the 802.11 standard that added new mechanisms for a faster initial link setup time. IEEE 802.11aj is a derivative of 802.11ad for use in the 45 GHz unlicensed spectrum available in some regions of the world (specifically China); it also provides additional capabilities for use in

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3796-509: The chair of IEEE 802.11 for 10 years, and has been called the "father of Wi-Fi", was involved in designing the initial 802.11b and 802.11a standards within the IEEE . He, along with Bell Labs Engineer Bruce Tuch, approached IEEE to create a standard. In 1999, the Wi-Fi Alliance was formed as a trade association to hold the Wi-Fi trademark under which most products are sold. The major commercial breakthrough came with Apple's adoption of Wi-Fi for their iBook series of laptops in 1999. It

3869-490: The current scope of the existing standard, which amendments may also include corrections to a previous specification. 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 2.4-GHz band. Because of this choice of frequency band, 802.11b/g/n equipment may occasionally suffer interference in

3942-557: The data rate) and, of course, the energy with which the wireless signal is received. The latter is determined by distance and by the configured output power of the communicating devices. Half-duplex A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide

4015-403: The difference in the frame (header) lengths of these two media, the application's packet size determines the speed of the data transfer. This means applications that use small packets (e.g., VoIP) create dataflows with high-overhead traffic (i.e., a low goodput ). Other factors that contribute to the overall application data rate are the speed with which the application transmits the packets (i.e.,

4088-441: The direction of transmission in a half-duplex line. Full-duplex audio systems like telephones can create echo, which is distracting to users and impedes the performance of modems. Echo occurs when the sound originating from the far end comes out of the speaker at the near end and re-enters the microphone there and is then sent back to the far end. The sound then reappears at the original source end but delayed. Echo cancellation

4161-405: The end of transmission, to ensure that only one party transmits at a time. A good analogy for a half-duplex system would be a one-lane road that allows two-way traffic, traffic can only flow in one direction at a time. Half-duplex systems are usually used to conserve bandwidth , at the cost of reducing the overall bidirectional throughput, since only a single communication channel is needed and

4234-411: The existing 11ad, aimed to extend the throughput, range, and use-cases. The main use-cases include indoor operation and short-range communications due to atmospheric oxygen absorption and inability to penetrate walls. The peak transmission rate of 802.11ay is 40 Gbit/s. The main extensions include: channel bonding (2, 3 and 4), MIMO (up to 4 streams) and higher modulation schemes. The expected range

4307-547: The half-duplex and simplex capacity of their new transatlantic telegraph cable completed between Newfoundland and the Azores in 1928. The same definition for a simplex radio channel was used by the National Fire Protection Association in 2002. A half-duplex ( HDX ) system provides communication in both directions, but only one direction at a time, not simultaneously in both directions. This terminology

4380-423: The layer-2 data rates. However, this does not apply to typical deployments in which data is being transferred between two endpoints, of which at least one is typically connected to a wired infrastructure and the other endpoint is connected to an infrastructure via a wireless link. This means that, typically, data frames pass an 802.11 (WLAN) medium and are being converted to 802.3 ( Ethernet ) or vice versa. Due to

4453-450: The previous 802.11 standards; its first draft of certification was published in 2006. The 802.11n standard was retroactively labelled as Wi-Fi 4 by the Wi-Fi Alliance. The standard added support for multiple-input multiple-output antennas (MIMO). 802.11n operates on both the 2.4 GHz and the 5 GHz bands. Support for 5 GHz bands is optional. Its net data rate ranges from 54 Mbit/s to 600 Mbit/s. The IEEE has approved

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4526-551: The rapid acceptance of 802.11b as the definitive wireless LAN technology. Devices using 802.11b experience interference from other products operating in the 2.4 GHz band. Devices operating in the 2.4 GHz range include microwave ovens, Bluetooth devices, baby monitors, cordless telephones, and some amateur radio equipment. As unlicensed intentional radiators in this ISM band , they must not interfere with and must tolerate interference from primary or secondary allocations (users) of this band, such as amateur radio. In June 2003,

4599-427: The same time. Full-duplex operation is achieved on a two-wire circuit through the use of a hybrid coil in a telephone hybrid . Modern cell phones are also full-duplex. There is a technical distinction between full-duplex communication, which uses a single physical communication channel for both directions simultaneously, and dual-simplex communication which uses two distinct channels, one for each direction. From

4672-419: The speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channels between them. In a half-duplex or semiduplex system, both parties can communicate with each other, but not simultaneously; the communication is one direction at a time. An example of a half-duplex device

4745-453: The transmitter site to multiple receivers. A pair of walkie-talkie two-way radios provide a simplex circuit in the ITU sense; only one party at a time can talk, while the other listens until it can hear an opportunity to transmit. The transmission medium (the radio signal over the air) can carry information in only one direction. The Western Union company used the term simplex when describing

4818-403: The user perspective, the technical difference does not matter and both variants are commonly referred to as full duplex . Many Ethernet connections achieve full-duplex operation by making simultaneous use of two physical twisted pairs inside the same jacket, or two optical fibers which are directly connected to each networked device: one pair or fiber is for receiving packets, while the other

4891-627: The wireless client to know the WLAN supports OWE, it must receive a Probe Response from the wireless access point in response to its Probe Request. OWE still uses 802.11 Open System Authentication, then the Elliptic Curve Diffie-Hellman Ephemeral exchange occurs in the Association process. After Association is successful the 4-way handshake can occur, and from then on data frames are encrypted. This computer networking article

4964-429: Was added. It operates in the 5 GHz band with a maximum net data rate of 54 Mbit/s, plus error correction code, which yields realistic net achievable throughput in the mid-20 Mbit/s. It has seen widespread worldwide implementation, particularly within the corporate workspace. Since the 2.4 GHz band is heavily used to the point of being crowded, using the relatively unused 5 GHz band gives 802.11a

5037-408: Was authorized to "roll up" many of the amendments to the 1999 version of the 802.11 standard. 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. Upon approval on 8 March 2007, 802.11REVma was renamed to the then-current base standard IEEE 802.11-2007 . 802.11n is an amendment that improves upon

5110-452: 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. In addition much cleanup was done, including a reordering of many of the clauses. Upon publication on 29 March 2012, the new standard was referred to as IEEE 802.11-2012 . IEEE 802.11ac-2013 is an amendment to IEEE 802.11, published in December 2013, that builds on 802.11n. The 802.11ac standard

5183-473: Was retroactively labelled as Wi-Fi 5 by the Wi-Fi Alliance. Changes compared to 802.11n include wider channels (80 or 160 MHz versus 40 MHz) in the 5 GHz band, more spatial streams (up to eight versus four), higher-order modulation (up to 256- QAM vs. 64-QAM), and the addition of Multi-user MIMO (MU-MIMO). The Wi-Fi Alliance separated the introduction of ac wireless products into two phases ("waves"), named "Wave 1" and "Wave 2". From mid-2013,

5256-758: Was the first mass consumer product to offer Wi-Fi network connectivity, which was then branded by Apple as AirPort. One year later IBM followed with its ThinkPad 1300 series in 2000. The original version of the standard IEEE 802.11 was released in 1997 and clarified in 1999, but is now obsolete. It specified two net bit rates of 1 or 2 megabits per second (Mbit/s), plus forward error correction code. It specified three alternative physical layer technologies: diffuse infrared operating at 1 Mbit/s; frequency-hopping spread spectrum operating at 1 Mbit/s or 2 Mbit/s; and direct-sequence spread spectrum operating at 1 Mbit/s or 2 Mbit/s. The latter two radio technologies used microwave transmission over

5329-430: Was to provide 4 times the throughput -per-area of 802.11ac (hence High Efficiency ). The motivation behind this goal was the deployment of WLAN in dense environments such as corporate offices, shopping malls and dense residential apartments. This is achieved by means of a technique called OFDMA , which is basically multiplexing in the frequency domain (as opposed to spatial multiplexing , as in 802.11ac). This

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