LAN (local area network) is a data communications network that typically connects personal computers within a very limited geographical (usually within a single building). LANs use a variety of wired and wireless technologies, standards and protocols. School computer labs and home networks are examples of LANs. Consume more power but extend the connection to about 300 feet (100 meters).
PAN (personal area network) is a term used to refer to the interconnection of personal digital devices within a range of about 30 feet (10 meters) and without the use of wires or cables. For example, a PAN could be used to wirelessly transmit data from a notebook computer to a PDA or portable printer. Have a short range (up to 20–30 feet/7–10 meters), commonly use the 802.15 family of specifications to connect two or a few devices with low power consumption. Bluetooth is an example of WPAN protocol.
MAN (metropolitan area network) is a public high-speed network capable of voice and data transmission within a range of about 50 miles (80 km). Examples of MANs that provide data transport services include local ISPs, cable television companies, and local telephone companies. Extend the range to a larger geographic area, such as a city or suburb. Applications vary from point-to-point or point-to-multipoint links to multiuser coverage. WMANs typically use licensed frequencies (a fee has to be paid for permission to use the frequency), although implementations in the ISM bands can also be found. WiMAX is an example of WMAN protocol (most WiMAX implementations use licensed bands).
WAN (wide area network) covers a large geographical area and typically consists of several smaller networks, which might use different computer platforms and network technologies. The Internet is the world’s largest WAN. Networks for nationwide banks and superstore chains can be classified as WANs. Provide connectivity over a wide geographical area. Usually, WWANs are networks used for mobile phone and data service and are operated by carriers. WWANs typically use licensed frequencies.
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