Understanding ONT/ONU
ONU converts optical signals transmitted via fibers to electrical signals. These electrical signals are then sent to individual subscribers. In general, there is a distance or other access network between ONU and end user's premises. Furthermore, ONU can send, aggregate, and groom different types of data coming from the customer and send it upstream to the OLT. Grooming is the process that optimizes and reorganizes the data stream so it would be delivered more efficiently. OLT supports bandwidth allocation that allows making smooth delivery of data float to the OLT, which usually arrives in bursts from the customer. ONU could be connected by various methods and cable types, like twisted-pair copper wire, coaxial cable, optical fiber, or through Wi-Fi.
End-user devices may also be referred to as the optical network terminal (ONT). Actually, ONT is the same as ONU in essence. ONT is an ITU-T term, whereas ONU is an IEEE term. Belong to different standard bodies, they both refer to the user side equipment in the GEPON system. But in practice, there is a little difference between ONT and ONU according to their location.
Type of ONU
GPON ONU/ONT
XPON ONU/ONT
EPON ONU/ONT
ONU can be divided into six types, namely
SFU (Single Family Unit) ONU,
HGU (Home Gateway Unit) ONU,
MDU (Multi-Dwelling Unit) ONU,
SBU (Single Business Unit) ONU,
MTU (Multi-Tenant Unit) ONU
CBU (Cellular Backhaul Unit) ONU
ONT/ONU NETWORK ARCHITACTURE