from here: https://discord.com/channels/780082494447288340/780082494447288344/842722278907052032
actually, I just noticed that steam has open sourced parts of their networking library as BSD (so it could be used with stratagus): https://github.com/ValveSoftware/GameNetworkingSockets
in particular, they use more sophisticated methods to route through corporate networks, and those should "just work". they even have some documentation how to convert UDP code to their classes
from here: https://discord.com/channels/780082494447288340/780082494447288344/842722278907052032