For CenturyLink fiber I have two boxes:
Box A: the exterior fiber enters this box, the tech said it was a "translator"; and the port 4 ethernet on it goes to ...
Box B: the centurylink wireless router, which performs the PPoE with my credentials which were somehow hardwired because no one ever told me my username/password. I'm guesing TR-069? Then port 4 on this goes to ...
Box C: MY WRT1900AC, which then goes to other subnets for my cameras, lab, and office.
I figured Box B was redundant, but trying to remove it has been problematic.