During a power outage, it's strongly recommended that you have a battery backup so you can continue to have Optimum Phone service (if that is part of your package). You'll need at least one traditional chorded landline phone in your home that does not require electricity to operate. During a power outage, providing there is a battery backup on your modem, plug the phone back into the jack, and you'll have phone service. \r\rFor business customers, keep your modem plugged into the outlet where the technician installed it. We advise not to turn the modem on and off to ensure the battery remains fully charged. Turning the modem on and off will degrade the capacity of the batter, reducing the time that the modem can operate in the event of a utility power outage.