As I understand it, that is basically the purpose of UPnP IGD [0], as well as the newer PCP [1]. But hardly anyone implements these protocols due to the usual c

As I understand it, that is basically the purpose of UPnP IGD [0], as well as the newer PCP [1]. But hardly anyone implements these protocols due to the usual concerns around incoming connections. [0] https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protocol https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protoc... [1] https://en.wikipedia.org/wiki/Port_Control_Protocol https://en.wikipedia.org/wiki/Port_Control_Protocol