Wondering what is (or was) the use case here: Cube clients can connect either through "eventing mode" or through "polling", with the latter being just some sort of quick workaround (plan B solution) that a DataMiner system provides by default if the required set of ports are blocked for any given reason. This is based on ".NET Remoting".
Cube connections require a range of ports that needs to be allowed on the involved firewalls.

Within a production environment, I believe the general recommendation is still to work with "eventing" as this allows a faster notification (from servers to clients), rather than with "polling" (from the client to the servers), if nothing else as the latter increases the load on servers lineraly with the number of Cube clients connected.