Re: OK I'm biting..
Once I did try keeping all of that gear on a UPS, because the power supply here was rather flaky at the time. But I made the mistake of buying a "eco smart" device, that decided all by itself if the power consumption was below some arbitrary threshold that could not be adjusted after the device left the factory then it should switch itself off! Of course you will realise by now that the total demand of modem/router, POE box and SIP phones was insufficient to keep the UPS turned on! Where did I leave that drawing board?