Wireless networking is a method by which homes, telecommunications networks and business installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. Wireless telecommunications networks are generally implemented and administered using radio communication. This implementation takes place at the physical level (layer) of the OSI model network structure.
The first professional wireless network was developed under the brand ALOHAnet in 1969 at the University of Hawaii and became operational in June 1971. The first commercial wireless network was the WaveLAN product family, developed by NCR in 1986.
Wireless personal area networks (WPANs) connect devices within a relatively small area, that is generally within a person's reach. For example, both Bluetooth radio and invisible infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications. Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.
A wireless local area network (WLAN) links two or more devices over a short distance using a wireless distribution method, usually providing a connection through an access point for internet access. The use of spread-spectrum or OFDM technologies may allow users to move around within a local coverage area, and still remain connected to the network.
Products using the IEEE 802.11 WLAN standards are marketed under the Wi-Fi brand name . Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link. To connect to Wi-Fi, sometimes are used devices like a router or connecting HotSpot using mobile smartphones.
A wireless ad hoc network, also known as a wireless mesh network or mobile ad hoc network (MANET), is a wireless network made up of radio nodes organized in a mesh topology. Each node forwards messages on behalf of the other nodes and each node performs routing. Ad hoc networks can "self-heal", automatically re-routing around a node that has lost power. Various network layer protocols are needed to realize ad hoc mobile networks, such as Distance Sequenced Distance Vector routing, Associativity-Based Routing, Ad hoc on-demand Distance Vector routing, and Dynamic source routing.
Wireless metropolitan area networks are a type of wireless network that connects several wireless LANs.
Wireless wide area networks are wireless networks that typically cover large areas, such as between neighbouring towns and cities, or city and suburb. These networks can be used to connect branch offices of business or as a public Internet access system. The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz and 5.8Ghz band, rather than omnidirectional antennas used with smaller networks. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photovoltaic solar panels or wind systems they can be stand alone systems.
A cellular network or mobile network is a radio network distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. In a cellular network, each cell characteristically uses a different set of radio frequencies from all their immediate neighbouring cells to avoid any interference.
When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers (e.g., mobile phones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.
A global area network (GAN) is a network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off user communications from one local coverage area to the next. In IEEE Project 802, this involves a succession of terrestrial wireless LANs.
Space networks are networks used for communication between spacecraft, usually in the vicinity of the Earth. The example of this is NASA's Space Network.
Some examples of usage include cellular phones which are part of everyday wireless networks, allowing easy personal communications. Another example, Intercontinental network systems, use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively as well. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.
In a general sense, wireless networks offer a vast variety of uses by both business and home users.
"Now, the industry accepts a handful of different wireless technologies. Each wireless technology is defined by a standard that describes unique functions at both the Physical and the Data Link layers of the OSI model. These standards differ in their specified signaling methods, geographic ranges, and frequency usages, among other things. Such differences can make certain technologies better suited to home networks and others better suited to network larger organizations."
Each standard varies in geographical range, thus making one standard more ideal than the next depending on what it is one is trying to accomplish with a wireless network. The performance of wireless networks satisfies a variety of applications such as voice and video. The use of this technology also gives room for expansions, such as from 2G to 3G and, 4G and 5G technologies, which stand for the fourth and fifth generation of cell phone mobile communications standards. As wireless networking has become commonplace, sophistication increases through configuration of network hardware and software, and greater capacity to send and receive larger amounts of data, faster, is achieved. Now the wireless network has been running on LTE, which is a 4G mobile communication standard. Users of an LTE network should have data speeds that are 10x faster than a 3G network. 
Space is another characteristic of wireless networking. Wireless networks offer many advantages when it comes to difficult-to-wire areas trying to communicate such as across a street or river, a warehouse on the other side of the premises or buildings that are physically separated but operate as one. Wireless networks allow for users to designate a certain space which the network will be able to communicate with other devices through that network.
Space is also created in homes as a result of eliminating clutters of wiring. This technology allows for an alternative to installing physical network mediums such as TPs, coaxes, or fiber-optics, which can also be expensive.
For homeowners, wireless technology is an effective option compared to Ethernet for sharing printers, scanners, and high-speed Internet connections. WLANs help save the cost of installation of cable mediums, save time from physical installation, and also creates mobility for devices connected to the network. Wireless networks are simple and require as few as one single wireless access point connected directly to the Internet via a router.
The telecommunications network at the physical layer also consists of many interconnected wireline network elements (NEs). These NEs can be stand-alone systems or products that are either supplied by a single manufacturer or are assembled by the service provider (user) or system integrator with parts from several different manufacturers.
Reliable wireless service depends on the network elements at the physical layer to be protected against all operational environments and applications (see GR-3171, Generic Requirements for Network Elements Used in Wireless Networks – Physical Layer Criteria).
What are especially important are the NEs that are located on the cell tower to the base station (BS) cabinet. The attachment hardware and the positioning of the antenna and associated closures and cables are required to have adequate strength, robustness, corrosion resistance, and resistance against wind, storms, icing, and other weather conditions. Requirements for individual components, such as hardware, cables, connectors, and closures, shall take into consideration the structure to which they are attached.
Compared to wired systems, wireless networks are frequently subject to electromagnetic interference. This can be caused by other networks or other types of equipment that generate radio waves that are within, or close, to the radio bands used for communication. Interference can degrade the signal or cause the system to fail.
Some materials cause absorption of electromagnetic waves, preventing it from reaching the receiver, in other cases, particularly with metallic or conductive materials reflection occurs. This can cause dead zones where no reception is available. Aluminium foiled thermal isolation in modern homes can easily reduce indoor mobile signals by 10 dB frequently leading to complaints about the bad reception of long-distance rural cell signals.
The hidden node problem occurs in some types of network when a node is visible from a wireless access point (AP), but not from other nodes communicating with that AP. This leads to difficulties in media access control (collisions).
The wireless spectrum is a limited resource and shared by all nodes in the range of its transmitters. Bandwidth allocation becomes complex with multiple participating users. Often users are not aware that advertised numbers (e.g., for IEEE 802.11 equipment or LTE networks) are not their capacity, but shared with all other users and thus the individual user rate is far lower. With increasing demand, the capacity crunch is more and more likely to happen. User-in-the-loop (UIL) may be an alternative solution to ever upgrading to newer technologies for over-provisioning.
Shannon's theorem can describe the maximum data rate of any single wireless link, which relates to the bandwidth in hertz and to the noise on the channel.
One can greatly increase channel capacity by using MIMO techniques, where multiple aerials or multiple frequencies can exploit multiple paths to the receiver to achieve much higher throughput – by a factor of the product of the frequency and aerial diversity at each end.
Under Linux, the Central Regulatory Domain Agent (CRDA) controls the setting of channels.
The total network bandwidth depends on how dispersive the medium is (more dispersive medium generally has better total bandwidth because it minimises interference), how many frequencies are available, how noisy those frequencies are, how many aerials are used and whether a directional antenna is in use, whether nodes employ power control and so on.
Cellular wireless networks generally have good capacity, due to their use of directional aerials, and their ability to reuse radio channels in non-adjacent cells. Additionally, cells can be made very small using low power transmitters this is used in cities to give network capacity that scales linearly with population density.
Wireless access points are also often close to humans, but the drop off in power over distance is fast, following the inverse-square law. The position of the United Kingdom's Health Protection Agency (HPA) is that “...radio frequency (RF) exposures from WiFi are likely to be lower than those from mobile phones.” It also saw “...no reason why schools and others should not use WiFi equipment.” In October 2007, the HPA launched a new “systematic” study into the effects of WiFi networks on behalf of the UK government, in order to calm fears that had appeared in the media in a recent period up to that time". Dr Michael Clark, of the HPA, says published research on mobile phones and masts does not add up to an indictment of WiFi.
[…] Central Regulatory Domain Agent (CRDA) […] controls the channels to be set on the system, based on the regulations of each country.
All the expert reviews done here and abroad indicate that there is unlikely to be a health risk from wireless networks. … When we have conducted measurements in schools, typical exposures from WiFi are around 20 millionths of the international guideline levels of exposure to radiation. As a comparison, a child on a mobile phone receives up to 50 percent of guideline levels. So a year sitting in a classroom near a wireless network is roughly equivalent to 20 minutes on a mobile. If WiFi should be taken out of schools, then the mobile phone network should be shut down, too—and FM radio and TV, as the strength of their signals is similar to that from WiFi in classrooms....
Ameritech Mobile Communications, LLC was the first company in the United States to provide cellular mobile phone service to the general public. Cell service became publicly available in Chicago on October 13, 1983. The company was a division of Ameritech which, as of January 1, 1984, was the holding company of Illinois Bell, Michigan Bell, Wisconsin Bell, Ohio Bell, and Indiana Bell, which provides landline service to the Great Lakes region. From around 1986, Cincinnati Bell held a 45% stake in the company. Originally named Ameritech Mobile Communications, it later became known as Ameritech Cellular.
Before the SBC Merger Ameritech sold some of its interests to GTE dba Verizon. Following the SBC Communications merger, Ameritech's wireless network was integrated and added to SBC's Wireless network. Originally Ameritech used CDMA as its network technology choice, but then converted to TDMA to be compatible with SBC's other wireless networks that were mostly using TDMA. During the SBC Communications merger its First and Original network in Chicago was sold to GTE (which later became Verizon Wireless).
Ameritech Mobile Communications exists today as Ameritech Mobile Communications, LLC d/b/a AT&T Mobility.
The Guinness Records claims "the Most durable mobile phone number (cellular phone number) David Contorno, of Lemont, Illinois, has owned and used the same mobile telephone number since 2 August 1985. His first mobile phone was an Ameritech AC140 and his carrier has been Ameritech Mobile Communications ever since."BellSouth Mobility DCS
BellSouth Mobility DCS, LLC headquartered in Atlanta, Georgia, was a BellSouth subsidiary.
BellSouth Mobility DCS operated 1900 MHz GSM networks in a number of states in the South, clustered around South Carolina.Centrino
Centrino is a brand name of Intel Corporation which represents its Wi-Fi and WiMAX wireless computer networking adapters. Previously the same brand name was used by the company as a platform-marketing initiative. The change of the meaning of the brandname occurred on January 7, 2010.
The old platform-marketing brand name covered a particular combination of mainboard chipset, mobile CPU and wireless network interface in the design of a laptop. Intel claimed that systems equipped with these technologies delivered better performance, longer battery life and broader wireless network interoperability than non-Centrino systems.
The new product line name for Intel wireless products is Intel Centrino Wireless.ESPN MVP
ESPN MVP was a cellular phone-based sports information service offered by ESPN and Verizon Wireless on feature phones. It was carried on the Verizon Wireless network after it was relaunched in May 2007 as the ESPN MVP, and was operated until 2013, when smartphones with mobile web and application access had long supplanted limited feature phones. Previously known as Mobile ESPN, it was a Mobile Virtual Network Operator (MVNO) run by Disney using Sprint's EVDO wireless network from November 25, 2005, until December 2006. The service was widely considered overpriced and a failure.Engineering Research Center for Wireless Integrated Microsystems
The NSF Engineering Research Center for Wireless Integrated Microsystems (ERC WIMS) was formed in 2000 in Michigan — through the collaboration of the University of Michigan (UM), Michigan State University (MSU), and Michigan Technological University.
The center is funded by the National Science Foundation. Additional contributions came from the state of Michigan, the three partnering core universities, other federal agencies, and a consortium of about twenty companies.First Responder Network Authority
The First Responder Network Authority (FirstNet) of the United States was created under the Middle Class Tax Relief and Job Creation Act of 2012 (MCTRJCA) as an independent authority within the National Telecommunications and Information Administration (NTIA). The purpose of FirstNet is to establish, operate, and maintain an interoperable public safety broadband network. To fulfill these objectives, Congress allotted $7 billion and 20 MHz of valuable radio spectrum to build the network.IEEE 802.11v
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 802.11 is a set of IEEE standards that govern wireless networking transmission methods. They are commonly used today in their 802.11a, 802.11b, 802.11g, 802.11n, and 802.11ac versions to provide wireless connectivity in the home, office and some commercial establishments.Independent Media Center
The Independent Media Center (also known as Indymedia or IMC) is an open publishing network of journalist collectives that report on political and social issues. It originated in Australia, tested also in London during the June 18th Carnival against Capital then came to wider prominence during the Seattle anti-WTO protests worldwide in 1999 and remains closely associated with the global justice movement, which criticizes neo-liberalism and its associated institutions. Several local branches of the network have been raided by law enforcement over the years.LPWAN
A low-power wide-area network (LPWAN) or low-power wide-area (LPWA) network or low-power network (LPN) is a type of wireless telecommunication wide area network designed to allow long range communications at a low bit rate among things (connected objects), such as sensors operated on a battery.
The low power, low bit rate and intended use distinguish this type of network from a wireless WAN that is designed to connect users or businesses, and carry more data, using more power. The LPWAN data rate ranges from 0.3 kbit/s to 50 kbit/s per
channel.A LPWAN may be used to create a private wireless sensor network, but may also be a service or infrastructure offered by a third party, allowing the owners of sensors to deploy them in the field without investing in gateway technology.LTE Advanced
LTE Advanced is a mobile communication standard and a major enhancement of the Long Term Evolution (LTE) standard. It was formally submitted as a candidate 4G to ITU-T in late 2009 as meeting the requirements of the IMT-Advanced standard, and was standardized by the 3rd Generation Partnership Project (3GPP) in March 2011 as 3GPP Release 10.Mobile network operator
A Mobile Network Operator or MNO, also known as a wireless service provider, wireless carrier, cellular company, or mobile network carrier, is a provider of wireless communications services that owns or controls all the elements necessary to sell and deliver services to an end user including radio spectrum allocation, wireless network infrastructure, back haul infrastructure, billing, customer care, provisioning computer systems and marketing and repair organizations.In addition to obtaining revenue by offering retail services under its own brand, an MNO may also sell access to network services at wholesale rates to mobile virtual network operators (MVNO).
A key defining characteristic of a mobile network operator is that an MNO must own or control access to a radio spectrum license from a regulatory or government entity. A second key defining characteristic of an MNO is that it must own or control the elements of the network infrastructure necessary to provide services to subscribers over the licensed spectrum.A mobile network operator typically also has the necessary provisioning, billing and customer care computer systems and the marketing, customer care and engineering organizations needed to sell, deliver and bill for services. However, an MNO can outsource any of these systems or functions and still be considered a mobile network operator.Municipal wireless network
Municipal wireless network ('Municipal Wi-Fi or MWN) is a citywide wireless network. This usually works by providing municipal broadband via Wi-Fi to large parts or all of a municipal area by deploying a wireless mesh network. The typical deployment design uses hundreds of wireless access points deployed outdoors, often on poles. The operator of the network acts as a wireless internet service provider.Network virtualization
In computing, network virtualization or network virtualisation is the process of combining hardware and software network resources and network functionality into a single, software-based administrative entity, a virtual network. Network virtualization involves platform virtualization, often combined with resource virtualization.
Network virtualization is categorized as either external virtualization, combining many networks or parts of networks into a virtual unit, or internal virtualization, providing network-like functionality to software containers on a single network server.
In software testing, software developers use network virtualization to test software which are under development in a simulation of the network environments in which the software is intended to operate. As a component of application performance engineering, network virtualization enables developers to emulate connections between applications, services, dependencies, and end users in a test environment without having to physically test the software on all possible hardware or system software. The validity of the test depends on the accuracy of the network virtualization in emulating real hardware and operating systems.WINLAB (Rutgers University)
WINLAB is the Wireless Information Network Laboratory, a research laboratory at Rutgers University, that is dedicated to research in a number of disciplines related to wireless communications. It consists of a number of faculty members from the Computer Science and Electrical & Computer Engineering departments at Rutgers University and research scientists. It is housed on a separate facility, away from the main engineering campus of Rutgers University (Busch Campus). The lab is famous for a pioneering early work during the development of cellular networks. It also houses the ORBIT testbed, the largest indoor wireless testbed of its kind in the world, housing more than 1200 radio nodes in a single room. The laboratory has approximately 40 PhD students, 20 MS students, and 2 Undergraduate students advised by approximately 20 full-time professors. WINLAB is funded by grants from its industry sponsors, the National Science Foundation, as well as Rutgers University and other agencies.Wi-Fi
Wi-Fi () is a family of radio technologies that is commonly used for the wireless local area networking (WLAN) of devices which is based around the IEEE 802.11 family of standards. Wi‑Fi is a trademark of the Wi-Fi Alliance, which restricts the use of the term Wi-Fi Certified to products that successfully complete interoperability certification testing. Wi-Fi uses multiple parts of the IEEE 802 protocol family and is designed to seamlessly interwork with its wired sister protocol Ethernet.
Devices that can use Wi-Fi technologies include desktops and laptops, smartphones and tablets, smart TVs, printers, digital audio players, digital cameras, cars and drones. Compatible devices can connect to each other over Wi-Fi through a wireless access point as well as to connected Ethernet devices and may use it to access the Internet. Such an access point (or hotspot) has a range of about 20 meters (66 feet) indoors and a greater range outdoors. Hotspot coverage can be as small as a single room with walls that block radio waves, or as large as many square kilometres achieved by using multiple overlapping access points.
The different versions of Wi-Fi are specified by various IEEE 802.11 protocol standards, with the different radio technologies determining the ranges, radio bands, and speeds that may be achieved. Wi-Fi most commonly uses the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SHF ISM radio bands; these bands are subdivided into multiple channels. Each channel can be time-shared by multiple networks. These wavelengths work best for line-of-sight. Many common materials absorb or reflect them, which further restricts range, but can tend to help minimise interference between different networks in crowded environments. At close range, some versions of Wi-Fi, running on suitable hardware, can achieve speeds of over 1 Gbit/s.
Wi-Fi is potentially more vulnerable to attack than wired networks because anyone within range of a network with a wireless network interface controller can attempt access. Wi-Fi Protected Access (WPA) is a family of technologies created to protect information moving across Wi-Fi networks and includes solutions for personal and enterprise networks. Security features of WPA have included stronger protections and new security practices as the security landscape has changed over time.Wireless Zero Configuration
Wireless Zero Configuration (WZC), also known as Wireless Auto Configuration, or WLAN AutoConfig is a wireless connection management utility included with Microsoft Windows XP and later operating systems as a service that dynamically selects a wireless network to connect to based on a user's preferences and various default settings. This can be used instead of, or in the absence of, a wireless network utility from the manufacturer of a computer's wireless networking device. The drivers for the wireless adapter query the NDIS Object IDs and pass the available network names (SSIDs) to the service. The service then lists them in the user interface on the Wireless Networks tab in the connection's Properties or in the Wireless Network Connection dialog box accessible from the notification area. A checked (debug) build version of the WZC service can be used by developers to obtain additional diagnostic and tracing information logged by the service.Wireless ad hoc network
A wireless ad hoc network (WANET) or MANET (Mobile ad hoc network) is a decentralised type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers in wired networks or access points in managed (infrastructure) wireless networks. Instead, each node participates in routing by forwarding data for other nodes, so the determination of which nodes forward data is made dynamically on the basis of network connectivity and the routing algorithm in use.
In the Windows operating system, ad-hoc is a communication mode (setting) that allows computers to directly communicate with each other without a router.
Wireless mobile ad hoc networks are self-configuring, dynamic networks in which nodes are free to move. Wireless networks lack the complexities of infrastructure setup and administration, enabling devices to create and join networks "on the fly" – anywhere, anytime.Wireless community network
Wireless community networks (WCNs) or wireless community projects are organizations that take a grassroots approach to providing a viable alternative to municipal wireless networks for consumers.The wireless community networks frequently set up wireless mesh networks which rely primarily on the sharing of unmetered residential and business DSL and cable Internet. This sort of usage might be non-compliant with the Terms of Service (ToS) of the typical local providers that deliver their service via the consumer phone and cable duopoly. Wireless community network sometimes advocate complete freedom from censorship, and this position may be at odds with the Acceptable Use Policies of some commercial services used. Some internet service provider (ISPs) do allow sharing or reselling of bandwidth.Wireless network interface controller
A wireless network interface controller (WNIC) is a network interface controller which connects to a wireless radio-based computer network, rather than a wired network, such as Token Ring or Ethernet. A WNIC, just like other NICs, works on the Layer 1 and Layer 2 of the OSI Model. This card uses an antenna to communicate via microwave radiation. A WNIC in a desktop computer is traditionally connected using the PCI bus. Other connectivity options are USB and PC card. Integrated WNICs are also available, (typically in Mini PCI/PCI Express Mini Card form).
Early wireless network interface controllers were commonly implemented on expansion cards that plugged into a computer bus. The low cost and ubiquity of the Wi-Fi standard means that many newer mobile computers have a wireless network interface built into the motherboard.
The term is usually applied to IEEE 802.11 adapters; it may also apply to a NIC using protocols other than 802.11, such as one implementing Bluetooth connections.