In fiber-to-the-premises systems, the signal is transmitted to the customer premises using fiber optic technologies. Unlike many conventional telephone technologies, this does not provide power for premises equipment, nor is it suitable for direct connection to customer equipment. An ONT
(optical network terminal) is used to terminate the fiber optic line, demultiplex the signal into its component parts (voice telephone, television, and Internet), and provide power to customer telephones. As the ONT
must derive its power from the customer premises electrical supply, many ONTs have the option for a battery backup, to maintain service in the event of a power outage. As one of the important part, ONT terminal directly affect the reliability of the entire solution, maintainability and scalability.