"Segregated 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).

    Segregated mode routing works in the following way:

    A special check is made on the packet to determine if the packet is
    Phase IV translatable.  If the packet is Phase IV translatable, it will
    translate the packet.  It will then send the translated Phase IV packet
    (or the Phase V packet if it couldn't be translated) to the appropriate
    router if the Phase IV or Phase V router is present.  If no suitable
    router is present, then the packet is sent directly to the destination
    end system.  (Essentially, Phase IV compatible packets are routed via
    the Phase IV backbone, and extended address packets are routed via the
    Phase V backbone.)

    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.