In a system for sucking and discharging a solution from a vessel by suction nozzles 2, processes for suction, discharge, separation, etc. The two wings are provided with two openings arranged facing one another and each having an edge in the form of an inclined ramp performing guiding of a karabiner passing through the two openings. Then the system transmits VoIP traffic over at least one of the tunnels from the controller at the local site to the other controller.