[openob-users] Openob - streaming from 4 locations

Hi all I'm working with a community radio station and looking for suggestions on how best to receive the OpenOB streams from  (4) remote studios to the hub studio (single fixed IP). The remote studios have RasPi4 OpenOB senders, the hub end will be (4) RasPi4 OpenOB receivers, audio from each receiver will be selectable, as required, for re-broadcast on the main FM Station. The audio switching at the hub end all figured out and tested. All remote studios have broadband service (Satellite and no fixed IP), I have a single test site that has been streaming for the past couple of months and works fine. However I have not resolved how best to now get the (4) OpenOB remote studios, sending to the single fixed IP at the hub end and received on their respective RasPi OpenOB receivers. After experiencing one hack on the test stream's exposed redis server (not surprised), It is now obvious I will  now need to secure all the streams on a working system. I have looked at a couple of options, such as a local OpenVPN server, OpenVPN with IPvanish server, spiped or Zerotier (as suggested by Klaus),. With many options, I am looking for guidance at this point on best way to go. Any help, comments or suggestions would be most welcome. Regards..Evan ============