Third view
  Metropolitan area network (man)
    Networking concept originated with the phone company,
      when many cities smaller and had their own phone service.

    In between local and wide area
      City wide or sparsely distributed over distance (blocks or few mile).

    Dissimilar technologies on different sub-nets but all parts usually
      considered part of a single network or domain (ownership).

      e.g niu.edu

    Sometime referred to as a private wan.

    Many broadcast sub-nets.
    
    With p to p connections between local networks and buildings
      feeding into routers.

    NIU is a man.
      Multiple sub-nets.
        p to p fiber between buildings.  
        Building may house multiple local sub-nets.

        Portions of NIU network located in Naperville, Hoffman Estates,
          and Rockford.

      Different technologies, implemented on fiber and copper.
        100Mib Ethernet, WiFi, multi Gib Ethernet.

        At one time included, Token ring, Applenet, ATM, FDDI

      Currently, most technology Ethernet based at the packet level.