MAN is a relatively new class of network, it serves a role similar to an ISP, but for corporate users with large LANs. The MAN 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. MAN (like a WAN) is not generally owned by a single organization. The communications links and equipment in MAN 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. 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.
Metropolitan area network technologies include:
SONET/SDH
RPR
10 Gigabit Ethernet
Gigabit Ethernet
ATM
MPLS
TCP/IP
IP
WDM/DWDM
Voice over IP
Network Security
For more information on Next Generation Networks (PoS, EoS, WDM, DWDM, G.709, RPR, IPv6, MPLS and GMPLS), view this presentation.