Google Multi-Gig Router and Wifi Mesh Tri-Band Extender ports

#networking

I just upgraded to Google Fiber 2Gig and there doesn't seem to be much documentation about what each of the ports mean on the two devices that they provided:

I was able to find some FCC documents about each:

I contacted Google Support and got as much info as I could.

Google Multi-Gig Router ports

Google Multi-Gig Router ports

I have the model number GFRG300. There are 1 RJ-11 port, 5 RJ-45 ports, 1 USB port, and one SFP+ port. Starting from the top:

Google Wifi Tri-Band Mesh Extender with Wifi 6

Google Wifi Tri-Band Mesh Extender with Wifi 6 ports

I have the model number GFEX310. There are two RJ-45 ports and one USB port on the back of this device.

Going from left to right:

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