Voip service is interrupted during a power failure true or false

VoIP stands for Voice over Internet Protocol. VoIP is a digital telephone service in which calls are sent and received over the Internet. High speed Internet connection a VoIP phone service provider are needed in order to have this type of service.  
It is true, that VoIP service is interrupted during a power failure. You should have backup power supplies to support your VoIP network when the power is out in order to have uninterrupted service.