Metropolitan-area networks (MANs)
    Wireless bridge technologies that send signals across public areas can also be used to create a MAN. A MAN usually consists of two or more LANs in a common geographic area. 
For example, a bank with multiple branches may utilize a MAN. Typically, a service provider is used to connect two or more LAN sites using private communication lines or optical services. A MAN can also be created using wireless bridge technology by beaming signals across public areas.
Storage-area networks (SANs)
    A storage-area network (SAN) is a dedicated, high-performance network used to move data between servers and storage resources. Because it is a separate, dedicated network, it avoids any traffic conflict between clients and servers.
    SAN technology allows high-speed server-to-storage, storage-to-storage, or server-to-server connectivity. This method uses a separate network infrastructure that relieves any problems associated with existing network connectivity.
    SANs offer the following features:
  • Performance – SANs allow concurrent access of disk or tape arrays by two or more servers at high speeds. This provides enhanced system performance.
  • Availability – SANs have built-in disaster tolerance. Data can be duplicated on a SAN up to 10 km (6.2 miles) away.
  • Scalability – A SAN can use a variety of technologies. This allows easy relocation of backup data, operations, file migration, and data replication between systems.