Fiber optics with the C7100v modem/router combo

about the only thing you could potentially do would be to use the c7100v as an AP. And even that would need to be rigged. 

antinode has written a guide for the C6300 and it'd be similar with the C7100v

https://community.netgear.com/t5/Cable-Modems-Routers/Can-I-use-a-C6300-cable-modem-without-cable-internet/m-p/1463500

> How do you (or can you) connect At&t fiber optics (ONT) to the Netgear
> C7100v (voice) router/modem?

   Because the C7100V has no WAN/Internet Ethernet port, it's generally
useless as a router in a non-cable-TV environment.

   A cable modem+router is not _absolutely_ useless without a cable ISP
connection.  See, for example:

      https://community.netgear.com/t5/x/x/m-p/1463500

But it _is_ useless as a _router_.