"Integrated Mode Routing"

    If you are using the ADVANCED configuration, you have the option
    of using segregated mode routing or integrated mode routing
    (integrated mode routing is the default).

    Integrated mode routing works in the following way:

    If a Phase V router is present, then the packet will be sent to it.
    If a Phase V router is not present, then a check will be made to
    determine if the packet is Phase IV compatible.

    If the packet is Phase IV compatible then it will check to see if a
    Phase IV router is present and if it is then the packet will be sent
    to the Phase IV router.  If there is no Phase IV router present then
    the packet will be sent directly in Phase IV format to the destination
    end system and multicast to all end systems in Phase V format.

    If the packet is not Phase IV compatible and a Phase V router is not
    present, then the packet will be multicast to all end systems in
    Phase V format.