VOIP and UPS

[Perci]

Can anybody tell me whether buying a UPS to run my modem/router/phone is worthwhile? What I'm thinking of simulating, is the behavior a POTS has in a local power outage, but I don't know if the cable signal will be there. As I understand it, Shaw Digital Phone adds a battery somewhere upstream of the house to provide the capability, and I'm hoping that I can do the same. I assume the 'head-end' has some sort of battery/UPS/EPS, but I don't know if there are active components between me and them that will be down.

I know there are support folks from the cable company that visit these forums, so I'm hoping they will give me guidance.

TIA

PS.I tried searching the forums for previous posts, but UPS gets bit by the 4-char search limit, and I ran out of other keywords.