The dRofus client communicates different dRofus web servers all connect with the same IFC model server via TCP port range 9090-9095 for the Americas, TCP port range 9090-9102 for Europe and TCP port range 9090-9093 for Asia-Pacific.
For projects where dRofus' modelserver is utilised, the firewall must allow outgoing TCP traffic for at least one of these ports against <servername> (depending which server is used).
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, operated by Catenda. This model server is placed on AWS (Amazon Web Services)' cloud solution in Frankfurt, Germany.