> No, Hole Punching is a thing precisely because it (the blocking method) works reliably. A NAT router drops all inbound connections by default because it doesn

> No, Hole Punching is a thing precisely because it (the blocking method) works reliably. A NAT router drops all inbound connections by default because it doesn't know where to route them. This reliably protects devices on your network, because no inbound connections ever reach them. It is the state tracking that does the protection, which you do not need NAT to do: * https://en.wikipedia.org/wiki/Firewall_(computing)#Connection_tracking https://en.wikipedia.org/wiki/Firewall_(computing)#Connectio... * https://en.wikipedia.org/wiki/Stateful_firewall https://en.wikipedia.org/wiki/Stateful_firewall And by getting rid of NAT, you also remove the need for the convoluted bullshit of STUN/TURN/ICE, and all you're left with is PCP: * https://en.wikipedia.org/wiki/Port_Control_Protocol https://en.wikipedia.org/wiki/Port_Control_Protocol * https://en.wikipedia.org/wiki/Hole_punching_(networking) https://en.wikipedia.org/wiki/Hole_punching_(networking)