A passive optical network consists of an optical line terminal (OLT) at the service provider's central office (hub), passive (non-power-consuming) optical splitters, and a number of optical network units (ONUs) or optical network terminals (ONTs), which are near end users. In practice, PONs are typically used for the last mile between Internet service providers (ISP) and their customers. In essence, a PON is a fiber-optic system that delivers data from a single source to multiple endpoints using only. Key components of a Passive Optical Network include the Optical Line Terminal (OLT), Optical Network Unit (ONU) or Optical Network Terminal (ONT), Optical Distribution Network (ODN), and Optical Splitters. 5 Gbps to cutting-edge 50G-PON implementations in 2025, with 100G Coherent PON (CPON) technologies emerging as the next frontier for ultra-high-speed broadband delivery. Passive Optical Networks (PON).
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