[mrbluecoat]

Agreed. This statement sums up the obvious:

> Granted, the server was just two hops away from the client, and it didn't have to pass through the scary sea of the internet

[immibis]

Actually the Internet at large is fine with any protocol on top of IP. It's your home router's NAT function that can only handle UDP and TCP. Set it to bridge mode and use your computer as the router (if you need one) and you can send anything from that computer.

If you have CGNAT you're still screwed. Get one of those free ipv6 tunnels.