On October 30, 2020 at 10:53, highfigh said...
I haven't worked with this system, only broadband and DSL but the fact that he can go online with his computer just by connecting it to the same ethernet cable he used to connect to the router's WAN port tells me there's a modem somewhere.
If you refer to the upstream device as a router, PE (provider edge) or “layer 3 device” with the provider technicians you may have better luck. They don’t usually refer to an Ethernet router as a modem.
If you are getting a public IP then they are likely not using NAT (as there would be no reason to do so). They may have a transparent firewall that is clipping the traffic.
If you’re not getting a public IP from the provider, then there is an upstream router that is NATing. In that case the carrier may have to port forward on your behalf on their router/layer 3 device.
