LANs, MANs and WANs

Networks naturally divide into three types according to their size:-

Local Area Network

(LAN) is a network that runs at one site, typically in one building. The computers are often tightly coupled with some depending on others to provide I/O devices such as disk and printer.

Wide Area Network

(WAN) is a network spanning larger distances. Coupling is much looser and each computer can operate independently of the network.

Metropolitan Area Network

(MAN) is a geographically small WAN, typically less than 50 miles wide. It provides faster access to other sites within the same MAN than a WAN would. It has connection to a WAN to permit access to more remote sites. Oxford is part of a MAN that also includes Brookes University, Rutherford Laboratory and Reading University.

There is an overlap between LANs MANs and WANs. For example a campus network, such as the network here at Oxford has some features of a LAN (some computers provide services for others) and some of a WAN (computers run independently).