The subentities below the CSMA-CD module are:

    Node___CSMA-CD____Port
                    |
                    |_Station

    The CSMA-CD entity is the top-level entity in the hierarchy of
    entities belonging to the CSMA-CD module.

    A CSMA-CD PORT entity represents an access point to the service
    offered by the CSMA-CD module. A client transmits and receives
    data through a port. Ports are created and deleted by client use
    of open and close service interface procedures. The port-name
    refers to the port managed by this command.

    A CSMA-CD STATION entity manages a CSMA/CD controller. Wherever
    Phase IV DECnet manages a line, DECnet-Plus manages a station.
    Each station corresponds to a particular logical link control
    (LLC), medium access control (MAC), and physical attachment. The
    station-name refers to the station managed by this command.