said by mgraves1
:Yes, as many have noted the CableCo may not take the same precautions that you did to ensure continuity of power. This has some very specific implications for emergency services during a power outage. If you rely on their digital phone service you may lose 911 access when the power is out.
In my case this is why my primary ISP is connected via DSL, and cable is used as a backup. Cable might be faster, but DSL stays up during power outages without question.
Not all telco dsl stays up. CO based dsl will stay up. Has same backup as CO based POTS. Remote dslams may or may not have backup depending on provider where located etc.