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Piconet
A piconet is an ad hoc network that links a wireless user group of devices using Bluetooth technology protocols. A piconet consists of two or more devices occupying the same physical channel (synchronized to a common clock and hopping sequence). It allows one ''master'' device to interconnect with up to seven active ''slave'' devices. Up to 255 further slave devices can be inactive, or ''parked'', which the master device can bring into active status at any time, but an active station must go into parked first. Some examples of piconets include a cell phone connected to a computer, a laptop and a Bluetooth-enabled digital camera, or several PDAs that are connected to each other. Overview A group of devices are connected via Bluetooth technology in an ad hoc fashion. A piconet starts with two connected devices, and may grow to eight connected devices. Bluetooth communication always designates one of the Bluetooth devices as a main controlling unit or ''master'' unit. Other dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scatternet
A scatternet is a type of ad hoc computer network consisting of two or more piconets. The terms "scatternet" and "piconet" are typically applied to Bluetooth wireless technology. Description A ''piconet'' is the type of connection that is formed between two or more Bluetooth-enabled devices such as modern cell phones. Bluetooth enabled devices are "peer units" in that they are able to act as either master or slave. However, when a piconet is formed between two or more devices, one device takes the role of the 'master', and all other devices assume a 'slave' role for synchronization reasons. Piconets have a 7 member address space (3 bits, with zero reserved for broadcast), which limits the maximum size of a piconet to 8 devices, i.e. 1 master and 7 slaves. A ''scatternet'' is a number of interconnected piconets that supports communication between more than 8 devices. Scatternets can be formed when a member of one piconet (either the master or one of the slaves) elects to partici ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 proposed type of mobile ad hoc network (MANET) involving road vehicles. VANETs were first proposed in 2001 as " car-to-car ad-hoc mobile communication and networking" applications, where networks could be f ... ** Intelligent vehicular ad hoc network * Protocols associated with ad hoc networking ** Ad hoc On-Demand Distance Vector Routing **Ad Hoc Configuration Protocol * Smart phone ad hoc network * Ad hoc wireless distribution service References {{networking-stub Computer networks engineering ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless User Group
Wireless community networks or wireless community projects or simply community networks, are non-centralized, self-managed and collaborative networks organized in a grassroots fashion by communities, non-governmental organizations and cooperatives in order to provide a viable alternative to municipal wireless networks for consumers. Many of these organizations set up wireless mesh networks which rely primarily on sharing of unmetered residential and business DSL and cable Internet. This sort of usage might be non-compliant with the terms of service of local internet service provider (ISPs) that deliver their service via the consumer phone and cable duopoly. Wireless community networks sometimes advocate complete freedom from censorship, and this position may be at odds with the acceptable use policies of some commercial services used. Some ISPs do allow sharing or reselling of bandwidth. The First Latin American Summit of Community Networks, held in Argentina in 2018, presented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 limited to 2.5 milliwatts, giving it a very short range of up to . It employs Ultra high frequency, UHF radio waves in the ISM bands, from 2.402GHz to 2.48GHz. It is mainly used as an alternative to wired connections to exchange files between nearby portable devices and connect cell phones and music players with wireless headphones, wireless speakers, HIFI systems, car audio and wireless transmission between TVs and soundbars. Bluetooth is managed by the Bluetooth Special Interest Group (SIG), which has more than 35,000 member companies in the areas of telecommunication, computing, networking, and consumer electronics. The Institute of Electrical and Electronics Engineers, IEEE standardized Bluetooth as IEEE 802.15.1 but no longer maintains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Master (device)
Master, master's or masters may refer to: Ranks or titles In education: *Master (college), head of a college *Master's degree, a postgraduate or sometimes undergraduate degree in the specified discipline *Schoolmaster or master, presiding officer of a school In military: *Master (naval), a former naval rank *Master mariner, a licensed mariner who is qualified to be a sea captain in the merchant marine *Master or shipmaster, the sea captain of a merchant vessel * Master-at-arms, a naval police officer, often addressed as "Master" in the Royal Navy In orders and organizations: *Master craftsman, in the Medieval guilds In other: *Master (form of address), an English honorific for boys and young men *Master (judiciary), a judicial official in the courts of common law jurisdictions *Master (Peerage of Scotland), the male heir-apparent or heir-presumptive to a title in the Peerage of Scotland * Master of ceremonies, or MC (emcee), the host of an official public or private staged even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slave (device)
Slavery is the ownership of a person as property, especially in regards to their labour. Slavery typically involves compulsory work, with the slave's location of work and residence dictated by the party that holds them in bondage. Enslavement is the placement of a person into slavery, and the person is called a slave or an enslaved person (see ). Many historical cases of enslavement occurred as a result of breaking the law, becoming indebted, suffering a military defeat, or exploitation for cheaper labor; other forms of slavery were instituted along demographic lines such as Racism, race or sex. Slaves would be kept in bondage for life, or for a fixed period of time after which they would be Manumission, granted freedom. Although slavery is usually involuntary and involves coercion, there are also cases where people voluntary slavery, voluntarily enter into slavery to pay a debt or earn money due to poverty. In the course of human history, slavery was a typical feature of civ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Phone
A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN). Modern mobile telephony relies on a cellular network architecture, which is why mobile phones are often referred to as 'cell phones' in North America. Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). Mobile phones also support a variety of multimedia capabilities, such as digital photography, video recording, and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Camera
A digital camera, also called a digicam, is a camera that captures photographs in Digital data storage, digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film or film stock. Digital cameras are now widely incorporated into mobile devices like smartphones with the same or more capabilities and features of dedicated cameras. High-end, high-definition dedicated cameras are still commonly used by professionals and those who desire to take higher-quality photographs. Digital and digital movie cameras share an optical system, typically using a Camera lens, lens with a variable Diaphragm (optics), diaphragm to focus light onto an image pickup device. The diaphragm and Shutter (photography), shutter admit a controlled amount of light to the image, just as with film, but the image pickup device is electronic rather than chemical. However, unlike film cameras, digital cameras can display images on a screen immediately afte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Digital Assistant
A personal digital assistant (PDA) is a multi-purpose mobile device which functions as a personal information manager. Following a boom in the 1990s and 2000s, PDAs were mostly displaced by the widespread adoption of more highly capable smartphones, in particular those based on iOS and Android (operating system), Android in the late 2000s, and thus saw a rapid decline. A PDA has an electronic visual display. Most models also have audio capabilities, allowing usage as a portable media player, and also enabling many of them to be used as telephones. By the early 2000s, nearly all PDA models had the ability to access the Internet, intranets or extranets via Wi-Fi or wireless WANs, and since then generally included a web browser. Sometimes, instead of buttons, later PDAs employ touchscreen technology. History The first PDA, the Psion Organiser, Organiser, was released in 1984 by Psion (company), Psion, followed by Psion Series 3, Psion's Series 3, in 1991. The latter began to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilobit
The bit is the most basic unit of information in computing and digital communication. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented as either , but other representations such as ''true''/''false'', ''yes''/''no'', ''on''/''off'', or ''+''/''−'' are also widely used. The relation between these values and the physical states of the underlying storage or device is a matter of convention, and different assignments may be used even within the same device or program. It may be physically implemented with a two-state device. A contiguous group of binary digits is commonly called a '' bit string'', a bit vector, or a single-dimensional (or multi-dimensional) ''bit array''. A group of eight bits is called one ''byte'', but historically the size of the byte is not strictly defined. Frequently, half, full, double and quadruple words consist of a number of bytes which is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Area Network
A personal area network (PAN) is a computer network for interconnecting electronic devices within an individual person's workspace. A PAN provides data transmission among devices such as computers, smartphones, tablets and personal digital assistants. PANs can be used for communication among the personal devices themselves, or for connecting to a higher level network and the Internet where one master device takes up the role as gateway. A PAN may be carried over wired interfaces such as USB, but is predominantly carried wirelessly, also called a wireless personal area network (WPAN). A PAN is wirelessly carried over a low-powered, short-distance wireless network technology such as IrDA, Wireless USB, Bluetooth, NearLink or Zigbee. The reach of a WPAN varies from a few centimeters to a few meters. WPANs specifically tailored for low-power operation of the sensors are sometimes also called low-power personal area network (LPPAN) to better distinguish them from low-power wid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
