Which protocols and ports should we enable for smooth setup?

[Jonathan-Eid]

My team and I have been setting up Kilo in our cloud environments and have been running in circles because the documentation doesn't specify which firewall rules to allow in our cloud environments. So far we have found to get cross location meshes to communicate with each other fluidly, we need ICMP and IPIP(94) firewall allow rules to be enabled within the same network that the nodes in each location mesh are running on. We also allowed UDP Port 51820 to receive traffic from anyone.

Are there any other protocols or ports we should allowlist to prevent unforeseen problems in the future?