ONU is a terminal access device, similar to the access switch that we often say. The difference is that ONU is a device in a PON network, not a device for our traditional network.
The new ONU is no longer just a device with PON, but also has multiple PoE power ports. For example, Feng Runda's EPS5081 is called ONU with PoE function.
The PON port is used to connect to the PON network. It often connects to the OLT through the optical splitter, receives the instructions transmitted by OLT, and sends the data of the front-end device to OLT.
The PoE port is the power supply port of the network. Through this port, the network devices can be directly supplied to them without additional power wiring. It should be noted that the connection between PoE port and network device must be connected by network cable, which is equal to transmitting data and power simultaneously on the same network cable.
The ONU with PoE port not only has all the functions of the ordinary ONU, but also has the power supply function, which is undoubtedly the best choice in some places and environments where the power is inconvenient.