said by Libra:I will be interested in seeing your non-technical solution when you complete it. Thank you.
One really non-technical solution is to run a BBU in front of the FiOS BBU. But this is not efficient.
My solution will be an adapter that will allow you to connect to an external battery to provide power to the ONT during an extended power outage.
I am testing operation with a 35AH battery. I will provide part numbers and step-by-step instructions.
My question for you is how long an extended power outage do you want to plan for? Longest I've ever seen here in 30 years is 4 days once, 2.5 days once, and 1 day three times, although I know others nearby have seen up to 7 days of outage. Very rare that a power outage lasts more than a few hours.
Others might say that the copper lines put the burden for power backup on the telco, but I say the difference in service price will pay for the added cost of backup power in your home.
This is really off-topic, so when ready, I will make a new topic.