ODN's main passive optical components do not include active devices such as OLTs, ONUs, or ONTs.

Passive Components in an ODN

An Optical Distribution Network (ODN) is composed entirely of passive optical components that guide, split, and protect optical signals without requiring electrical power. The main passive components include:

• Optical fiber cables: Feeder, distribution, and drop fibers that carry light signals between the central office and subscribers .
• Optical splitters: PLC or coupler splitters that divide a single optical signal into multiple outputs for point-to-multipoint distribution .
• Fiber distribution boxes (FDB) and splice closures: Protect and organize fiber splices and connections in the field .
• Connectors and patch cords: Enable plug-and-play terminations and interconnections between fibers .

Components Not Considered Passive

Active devices, which require electrical power to operate, are not part of the ODN's passive components. These include:

• Optical Line Terminal (OLT): Located at the central office, it generates and manages optical signals .
• Optical Network Unit (ONU) or Optical Network Terminal (ONT): Subscriber-side devices that convert optical signals to electrical signals for end-user equipment .

Key Distinction

The passive nature of ODN components ensures energy efficiency, minimal maintenance, and long service life. In contrast, active components like OLTs and ONUs perform signal processing and require power, making them outside the scope of ODN's passive infrastructure . In summary, while fibers, splitters, closures, and connectors are core passive elements of an ODN, active devices such as OLTs, ONUs, and ONTs are not included.