The LIU as you can see above is a meeting place for Fiber optic Cable, Fiber optic pigtails, Fiber optic adapters and Fiber optic patchcords.
The Fiber optic cables are anchored rigidly in the LIU and the fibers spliced to pigtails and plugged into respective adapters. From the picture you will see 12 adapters which means 12 fibers are available for use. Now Fiber optic patchcords can be used to extend these fibers to the fiber optic port of the active device be it switch, media converter or any other product with inbuilt fiber optic ports.
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