I have an ER605 which has 3 WANs configured, two of them are just connections to other routers, but one is configured as a PPoE connection over fibre. On most routers I am used to you can find current

I have just bought and installed an ER602 to allow to use use network fallover as a standalone device (i.e. without an Omada controller). Looking at the ports it is listening on, it seems ports 53, 80