Using Ethernet option with sphinx

I want to reach my drone using the Ethernet option, the documentation is pretty ambiguous.
According to the docs here we can connect to the drone from another machine:

If you really need to run the controller application from another machine belonging to the same IP network, you need to activate the port forwarding mode, by using the following command line option.

$ sphinx --port-forwarding=<remote_machine_IP_address> <my.drone>

I ran sphinx with the following command:

sphinx --port-forwarding= /opt/parrot-sphinx/usr/share/sphinx/drones/bebop2.drone

where is the IP address of the controller machine.
after runing this command I can see the virtual card created:

couple of questions here:
where should I specify the port with this command?
what should be done on SDK side and where to do it?
can we ping the virtual Ethernet card with the IP from the controller machine?