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In
computer networking A computer network is a collection of communicating computers and other devices, such as printers and smart phones. In order to communicate, the computers and devices must be connected by wired media like copper cables, optical fibers, or b ...
, a wireless access point (WAP) (also just access point (AP)) is a
networking hardware Networking hardware, also known as network equipment or computer networking devices, are electronic devices that are required for communication and interaction between devices on a computer network. Specifically, they mediate data transmission in ...
device that allows other Wi-Fi devices to connect to a wired network or wireless network. As a standalone device, the AP may have a wired or wireless connection to a
switch In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type o ...
or router, but in a
wireless router A wireless router or Wi-Fi router is a device that performs the functions of a router and also includes the functions of a wireless access point. It is used to provide access to the Internet or a private computer network. Depending on the m ...
it can also be an integral component of the networking device itself. A WAP and AP is differentiated from a
hotspot Hotspot, Hot Spot or Hot spot may refer to: Places * Hot Spot, Kentucky, a community in the United States Arts, entertainment, and media Fictional entities * Hot Spot (comics), a name for the DC Comics character Isaiah Crockett * Hot Spot (Tr ...
, which can be a physical location or digital location where Wi-Fi or WAP access is available.


Connections

An AP connects directly to a wired
local Local may refer to: Geography and transportation * Local (train), a train serving local traffic demand * Local, Missouri, a community in the United States Arts, entertainment, and media * ''Local'' (comics), a limited series comic book by Bria ...
area network, typically
Ethernet Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...
, and the AP then provides wireless connections using
wireless LAN A wireless LAN (WLAN) is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building ...
technology, typically Wi-Fi, for other devices to use that wired connection. APs support the connection of multiple wireless devices through their one wired connection.


Wireless data standards

There are many wireless data standards that have been introduced for wireless access point and
wireless router A wireless router or Wi-Fi router is a device that performs the functions of a router and also includes the functions of a wireless access point. It is used to provide access to the Internet or a private computer network. Depending on the m ...
technology. New standards have been created to accommodate the increasing need for faster wireless connections. Access points can provide backward compatibility with older Wi-Fi protocols as many devices were manufactured for use with older standards. *
802.11a IEEE 802.11a-1999 or 802.11a was an amendment to the IEEE 802.11 wireless local network specifications that defined requirements for an orthogonal frequency-division multiplexing (OFDM) communication system. It was originally designed to support w ...
* 802.11b *
802.11g IEEE 802.11g-2003 or 802.11g is an amendment to the IEEE 802.11 specification that operates in the 2.4 GHz microwave band. The standard has extended link rate to up to 54 Mbit/s using the same 20 MHz bandwidth as 802.11b uses to achieve 11& ...
*
802.11n IEEE 802.11n-2009, or 802.11n, is a wireless-networking standard that uses multiple antennas to increase data rates. The Wi-Fi Alliance has also retroactively labelled the technology for the standard as Wi-Fi 4. It standardized support for multi ...
(Wi-Fi 4) *
802.11ac IEEE 802.11ac-2013 or 802.11ac is a wireless networking standard in the IEEE 802.11 set of protocols (which is part of the Wi-Fi networking family), providing high-throughput wireless local area networks (WLANs) on the 5 GHz band. The stan ...
(Wi-Fi 5) *
802.11ax Wi-Fi 6, or IEEE 802.11ax, is an IEEE standard from the Wi-Fi Alliance, for wireless networks (WLANs). It operates in the 2.4 GHz and 5 GHz bands, with an extended version, Wi-Fi 6E, that adds the 6 GHz band. It is an upgrade from Wi-Fi 5 ( ...
(Wi-Fi 6/6E) * 802.11be (Wi-Fi 7)


Wireless access point vs. ad hoc network

Some people confuse wireless access points with
wireless ad hoc network A wireless ad hoc network (WANET) or mobile ad hoc network (MANET) is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers or wireless access points. Instead, ...
s. An ad hoc network uses a connection between two or more devices ''without'' using a wireless access point; the devices communicate directly. Because setup is easy and does not require an access point, an ad hoc network is used in situations such as a quick data exchange or a
multiplayer video game A multiplayer video game is a video game in which more than one person can play in the same game environment at the same time, either locally on the same computing system (couch co-op), on different computing systems via a local area network, or ...
. Due to its peer-to-peer layout, ad hoc Wi-Fi connections are similar to connections available using
Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is li ...
. Ad hoc connections are generally not recommended for a permanent installation.
Internet access Internet access is a facility or service that provides connectivity for a computer, a computer network, or other network device to the Internet, and for individuals or organizations to access or use applications such as email and the World Wide ...
via
ad hoc network An ad hoc network refers to technologies that allow network communications on an ad hoc basis. Associated technologies include: *Wireless ad hoc network *Mobile ad hoc network *Vehicular ad hoc network A Vehicular ad hoc network (VANET) is a prop ...
s, using features like
Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...
'
Internet Connection Sharing Internet Connection Sharing (ICS) is a Windows service that enables one Internet-connected computer to share its Internet connection with other computers on a local area network (LAN). The computer that shares its Internet connection serves as a ...
or dedicated software such a
WiFi Direct Access Point
may work well with a small number of devices that are close to each other, but ad hoc networks do not scale well. Internet traffic will converge to the nodes with direct internet connection, potentially congesting these nodes. For internet-enabled nodes, access points have a clear advantage, with the possibility of having a wired
LAN Lan or LAN may refer to: Science and technology * Local asymptotic normality, a fundamental property of regular models in statistics * Longitude of the ascending node, one of the orbital elements used to specify the orbit of an object in space * ...
.


Limitations

It is generally recommended that one
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 com ...
AP should have, at a maximum, 10–25 clients. However, the actual maximum number of clients that can be supported can vary significantly depending on several factors, such as type of APs in use, density of client environment, desired client throughput, etc. The range of
communication Communication is commonly defined as the transmission of information. Its precise definition is disputed and there are disagreements about whether Intention, unintentional or failed transmissions are included and whether communication not onl ...
can also vary significantly, depending on such variables as indoor or outdoor placement, height above ground, nearby obstructions, other electronic devices that might actively interfere with the signal by broadcasting on the same frequency, type of antenna, the current weather, operating
radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the u ...
, and the power output of devices. Network designers can extend the range of APs through the use of
repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Some ...
s, which amplify a radio signal, and reflectors, which only bounce it. In experimental conditions, wireless networking has operated over distances of several hundred kilometers. Most jurisdictions have only a limited number of frequencies legally available for use by wireless networks. Usually, adjacent APs will use different frequencies (channels) to communicate with their clients in order to avoid
interference Interference is the act of interfering, invading, or poaching. Interference may also refer to: Communications * Interference (communication), anything which alters, modifies, or disrupts a message * Adjacent-channel interference, caused by extra ...
between the two nearby systems. Wireless devices can "listen" for data traffic on other frequencies, and can rapidly switch from one frequency to another to achieve better reception. However, the limited number of frequencies becomes problematic in crowded downtown areas with tall buildings using multiple APs. In such an environment, signal overlap becomes an issue causing interference, which results in signal degradation and data errors. Wireless networking lags wired networking in terms of increasing
bandwidth Bandwidth commonly refers to: * Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range * Bandwidth (computing), the rate of data transfer, bit rate or thr ...
and
throughput Network throughput (or just throughput, when in context) refers to the rate of message delivery over a communication channel in a communication network, such as Ethernet or packet radio. The data that these messages contain may be delivered ov ...
. While (as of 2013) high-density
256-QAM Quadrature amplitude modulation (QAM) is the name of a family of digital modulation methods and a related family of analog modulation methods widely used in modern telecommunications to transmit information. It conveys two analog message signa ...
modulation, 3-antenna wireless devices for the consumer market can reach sustained real-world speeds of some 240 Mbit/s at 13 m behind two standing walls ( NLOS) depending on their nature or 360 Mbit/s at 10 m line of sight or 380 Mbit/s at 2 m line of sight (
IEEE The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE ...
802.11ac IEEE 802.11ac-2013 or 802.11ac is a wireless networking standard in the IEEE 802.11 set of protocols (which is part of the Wi-Fi networking family), providing high-throughput wireless local area networks (WLANs) on the 5 GHz band. The stan ...
) or 20 to 25 Mbit/s at 2 m line of sight (
IEEE The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE ...
802.11g IEEE 802.11g-2003 or 802.11g is an amendment to the IEEE 802.11 specification that operates in the 2.4 GHz microwave band. The standard has extended link rate to up to 54 Mbit/s using the same 20 MHz bandwidth as 802.11b uses to achieve 11& ...
), wired hardware of similar cost reaches closer to 1000 Mbit/s up to specified distance of 100 m with twisted-pair cabling in optimal conditions ( Category 5 (known as Cat-5) or better cabling with
Gigabit Ethernet In computer networking, Gigabit Ethernet (GbE or 1 GigE) is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T, is defined by the IEEE 802.3ab standard. It came into use in ...
). One impediment to increasing the speed of wireless communications comes from
Wi-Fi Wi-Fi () is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for Wireless LAN, local area networking of devices and Internet access, allowing nearby digital devices to exchange data by ...
's use of a shared communications medium: Thus, two stations in infrastructure mode that are communicating with each other even over the same AP must have each and every frame transmitted twice: from the sender to the AP, then from the AP to the receiver. This approximately halves the effective bandwidth, so an AP is only able to use somewhat less than half the actual over-the-air rate for data throughput. Thus a typical 54 Mbit/s wireless connection actually carries
TCP/IP The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are ...
data at 20 to 25 Mbit/s. Users of legacy wired networks expect faster speeds, and people using wireless connections keenly want to see the wireless networks catch up. By 2012, 802.11n based access points and client devices have already taken a fair share of the marketplace and with the finalization of the 802.11n standard in 2009 inherent problems integrating products from different vendors are less prevalent.


Security

Wireless access has special
security Security is protection from, or resilience against, potential harm (or other unwanted coercion). Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, or any other entity or ...
considerations. Many wired networks base the security on physical access control, trusting all the users on the local network, but if wireless access points are connected to the network, anybody within range of the AP (which typically extends farther than the intended area) can attach to the network. The most common solution is wireless traffic encryption. Modern access points come with built-in encryption. The first generation encryption scheme, WEP, proved easy to crack; the second and third generation schemes, WPA and
WPA2 Wi-Fi Protected Access (WPA) (Wireless Protected Access), Wi-Fi Protected Access 2 (WPA2), and Wi-Fi Protected Access 3 (WPA3) are the three security certification programs developed after 2000 by the Wi-Fi Alliance to secure wireless computer n ...
, are considered secure if a strong enough
password A password, sometimes called a passcode, is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of password-protected services t ...
or
passphrase A passphrase is a sequence of words or other text used to control access to a computer system, program or data. It is similar to a password in usage, but a passphrase is generally longer for added security. Passphrases are often used to control ...
is used. Some APs support hotspot style authentication using
RADIUS In classical geometry, a radius (: radii or radiuses) of a circle or sphere is any of the line segments from its Centre (geometry), center to its perimeter, and in more modern usage, it is also their length. The radius of a regular polygon is th ...
and other authentication servers. Opinions about wireless network security vary widely. For example, in a 2008 article for ''
Wired Wired may refer to: Arts, entertainment, and media Music * ''Wired'' (Jeff Beck album), 1976 * ''Wired'' (Hugh Cornwell album), 1993 * ''Wired'' (Mallory Knox album), 2017 * "Wired", a song by Prism from their album '' Beat Street'' * "Wired ...
'' magazine,
Bruce Schneier Bruce Schneier (; born January 15, 1963) is an American cryptographer, computer security professional, privacy specialist, and writer. Schneier is an Adjunct Lecturer in Public Policy at the Harvard Kennedy School and a Fellow at the Berkman ...
asserted the net benefits of open Wi-Fi without passwords outweigh the risks, a position supported in 2014 by Peter Eckersley of the
Electronic Frontier Foundation The Electronic Frontier Foundation (EFF) is an American international non-profit digital rights group based in San Francisco, California. It was founded in 1990 to promote Internet civil liberties. It provides funds for legal defense in court, ...
. The opposite position was taken by Nick Mediati in an article for ''
PC World ''PC World'' (stylized as PCWorld) is a global computer magazine published monthly by IDG. Since 2013, it has been an online-only publication. It offers advice on various aspects of PCs and related items, the Internet, and other personal tec ...
'', in which he advocates that every wireless access point should be protected with a password.


See also

*
Femtocell In telecommunications, a femtocell is a small, low-power cellular base station, typically designed for use in a home or small business. A broader term which is more widespread in the industry is ''small cell'', with ''femtocell'' as a subset. It t ...
– a local-area base station using cellular network standards such as UMTS, rather than Wi-Fi *
HomePlug HomePlug is the family name for various power line communications specifications under the HomePlug designation, each with unique capabilities and compatibility with other HomePlug specifications. Some HomePlug specifications target broadband ap ...
– wired LAN technology that has a few elements in common with Wi-Fi *
Lightweight Access Point Protocol Lightweight Access Point Protocol (LWAPP) is a protocol that can control multiple Wi-Fi wireless access points at once. This can reduce the amount of time spent on configuring, monitoring and troubleshooting a large network. The system will also all ...
– used to manage a large set of APs *
List of router firmware projects List of software created and maintained by people other than the manufacturer of the product. The extent of support for (and testing on) particular hardware varies from project to project. Embedded Notable Custom firmware, custom-firmware projects ...
*
Wi-Fi Direct Wi-Fi Direct is a Wi-Fi standard for wireless connections that allows two devices to establish a direct Wi-Fi connection without an intermediary wireless access point, Router (computing), router, or Internet connection. Wi-Fi Direct is single-hop ...
– a Wi-Fi standard that enables devices to connect with each other without requiring a (hardware) wireless access point and to communicate at typical Wi-Fi speeds *
WiMAX Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options. The WiMA ...
– wide-area wireless standard that has a few elements in common with Wi-Fi * , sometimes confused for access points, especially in mobile contexts


References

{{Reflist Access point Network access Telecommunications infrastructure Access point