[BBLISA] Internet service and power outages?

[Scott Ehrlich]

A thought that recently came to mind (uh, oh!)-

Cable companies use telephone pole-based powerline-powered amplifiers, yes?  If 
so, if power to my area goes out, even if I have a UPS at home, all 
coax-offered services should disappear, correct?

Now, DSL is phone-line offered.   If the central office has its own power 
source, and I have mine, if power did go out, I should still have uninterrupted 
Internet service unless/until my UPS dies.   Yes or no?

Just trying to see how logical and realistic this thought is.

Scott