The ONT – Optical Network Terminal (also known as the modem) is connected to the Termination Point (TP) via an optical fiber cable. Using an Ethernet cable, it connects to your router and converts light signals from your TP's fiber optic line into electronic signals that your router. It's an OTN box converts the fiber cable from outside and turns into ethernet that goes into your router but this is an old style OTN box but I know a few homes that has this box and still works no problem if you have problems contact your ISP and they can replace the OTN with a newer model. If you are a fibre customer, it's likely you'll have an Openreach modem (or ONT) installed. This white box connects to a fibre-optic cable that runs to your house and enables you to access our FTTP fibre network for broadband and voice. There are several lights on the ONT, when these lights change. The fiber optic cable does not plug directly into a standard home router because the signal type must be translated. Its primary, and most critical, function is to act as a signal converter.
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