PON is a point-to-multipoint (P2MP) optical access system, which can save fiber resources, ODN does not require power supply, user access is convenient, and supports multi-service access. It is a broadband fiber access technology that operators are currently vigorously promoting , There are mainly two technologies, EPON and GPON. PON system adopts WDM (Dense Wavelength Division Multiplexing) technology to realize single-fiber bidirectional transmission

The PON system is mainly composed of three parts: OLT, ODN, and ONU. ODN does not include active equipment. The OLT to ONU is connected through an optical splitter to form a P2MP (point-to-multipoint) structure.

Optical network unit (ONU/ONT).