Metropolitan Area Networks (MANs)
A Metropolitan Area Network (MAN) is one of a number of types
of networks (see also LAN and WAN). A MAN is a relatively new class of network, it serves a role similar to an ISP, but for corporate users with large LANs. There are three important features which discriminate MANs from LANs or WANs:
- The network size falls intermediate between LANs
and WANs. A MAN typically covers an area
of between 5 and 50 km diameter. Many MANs cover an area the
size of a city, although in some cases MANs may be as small as
a group of buildings or as large as the North of Scotland.
- A MAN (like a WAN) is not generally
owned by a single organisation. The MAN, its communications links
and equipment are generally owned by either a consortium of users
or by a single network provider who sells the service to the
users. This level of service provided to each user must therefore
be negotiated with the MAN operator, and some performance guarantees
are normally specified.
- A MAN often acts as a high speed network to allow sharing
of regional resources (similar to a large LAN).
It is also frequently used to provide a shared connection to
other networks using a link to a WAN.
A typical use of MANs to provide shared access to a wide area
network is shown in the figure below:
Use of MANs to provide regional networks which
share the cost of access to a WAN
Gorry Fairhurst - Date: 01/10/2001 EG3557