What is coax link privacy password?

Question

I have the Verizon router (CR1000A), and I noticed that, under the coax connection options (Network Settings > Network Connections > Coax), there is a privacy option where you can set up a coax password (see screenshot #1). (I believe this was an option for older Verizon routers too.)

The router manual recommends enabling coax link privacy (see screenshot #2), but that knocks my Fios TV box (VMS4100) and WiFi extender (E3200) offline. I couldn't find an option on the Fios TV box (VMS4100) to set a coax password. I didn't even try with the WiFi extender, since the TV box needs the coax to work properly.

Here are my questions:

* Does anyone know (1) anything about this and (2) if/how I could set up a coax password on the router, extender, and TV box?

* Alternatively, is there a way to make coax work only for specific mac addresses (i.e., TV box and WiFi extender)?

Router web admin UI:

Router manual:

Cang_Household · Accepted Answer

Coax privacy password is only recommended when you are sharing your coaxial cable network with someone else, and would like to prevent others from stealing your Internet.

Otherwise, there is no benefit.