Personal area network
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by spatial scope
A personal area network (PAN) is a computer network for interconnecting devices centered on an individual person's workspace. A PAN provides data transmission amongst devices such as computers, smartphones, tablets and personal digital assistants. PANs can be used for communication amongst the personal devices themselves, or for connecting to a higher level network and the Internet (an uplink) where one master device takes up the role as gateway. A PAN may be carried over wired computer buses such as USB.
A wireless personal area network (WPAN) is a low-powered PAN carried over a short-distance wireless network technology such as IrDA, Wireless USB, Bluetooth and ZigBee. The reach of a WPAN varies from a few centimeters to a few meters.
Wireless personal area network
A wireless personal area network (WPAN) is a personal area network in which the connections are wireless. IEEE 802.15 has produced standards for several types of PANs operating in the ISM band including Bluetooth. The Infrared Data Association has produced standards for WPANs which operate using infrared communications.
A WPAN could serve to interconnect all the ordinary computing and communicating devices that many people have on their desk or carry with them today; or it could serve a more specialized purpose such as allowing the surgeon and other team members to communicate during an operation.
A key concept in WPAN technology is known as plugging in. In the ideal scenario, when any two WPAN-equipped devices come into close proximity (within several meters of each other) or within a few kilometers of a central server, they can communicate as if connected by a cable. Another important feature is the ability of each device to lock out other devices selectively, preventing needless interference or unauthorized access to information.
The technology for WPANs is in its infancy and is undergoing rapid development. Proposed operating frequencies are around 2.4 GHz in digital modes. The objective is to facilitate seamless operation among home or business devices and systems. Every device in a WPAN will be able to plug into any other device in the same WPAN, provided they are within physical range of one another. In addition, WPANs worldwide will be interconnected. Thus, for example, an archeologist on site in Greece might use a PDA to directly access databases at the University of Minnesota in Minneapolis, and to transmit findings to that database.
Bluetooth uses short-range radio waves. While historically covering shorter distances associated with a PAN, the Bluetooth 5 standard, Bluetooth Mesh, have extended that range considerably. Further, long range Bluetooth routers with augmented antenna arrays connect Bluetooth devices up to 1,000 feet. Uses in a PAN include, for example, Bluetooth devices such as keyboards, pointing devices, audio head sets, printers may connect to personal digital assistants (PDAs), cell phones, or computers.
A Bluetooth PAN is also called a piconet (combination of the prefix "pico," meaning very small or one trillionth, and network), and is composed of up to 8 active devices in a master-slave relationship (a very large number of devices can be connected in "parked" mode). The first Bluetooth device in the piconet is the master, and all other devices are slaves that communicate with the master. A piconet typically has a range of 10 metres (33 ft), although ranges of up to 100 metres (330 ft) can be reached under ideal circumstances. With Bluetooth mesh networking the range and number of devices is extended by relaying information from one to another. Such a network doesn't have a master device and may or may not be treated as a PAN.
Infrared Data Association
Infrared Data Association (IrDA) uses infrared light, which has a frequency below the human eye's sensitivity. Infrared in general is used, for instance, in TV remotes. Typical WPAN devices that use IrDA include printers, keyboards, and other serial communication interfaces.
- Charles D. Knutson with Jeffrey M. Brown, IrDA Principles and Protocols, 2004, ISBN 0-9753892-0-3