I want to design a circuit that can operate dsl modem in absence of electricity... dsl modem operates at 6v... so any suggestions?

I want to design a circuit that can operate dsl modem in absence of electricity... dsl modem operates at 6v... so any suggestions?

Solar Panel, Charge circuit, and a Battery to carry through the night.
If You have moving water like a stream or something you could use that for power generation.
Does not need to be large.

Does it run on 6 volts ac or dc? Some run on ac and some on dc. Get an adapter plug that will fit the input and use a meter to find which wire is positive, it's usually the center of plug. Buy a battery pack and hook it up. That's it.