VOIP...part of the package.
And a backup for the cellular.
Redundant systems are part of preparedness.
Hello, this is customer service...
Did you try turning it off and turning it back on?
You have seen that redundant systems require different pathways. Using comcast for phone, cellular and data means that your redundancy flows over the same teeny tiny little fiber optic thread.
If one is down…it is likely they are ALL down.