To troubleshoot this problem, you need to inspect the connectors visually and use a power meter or an optical time-domain reflectometer (OTDR) to measure the optical power and attenuation at the FDC. In addition, the drawer structure also facilitates high-density wiring and good cable management. However, because optical fibers are fragile and can be easily. Fiber Distribution box (FDB), known as optical Distribution box (ODB) as well, is a compact fiber management product of small size. Fiber Distribution box. The fiber termination box is an interface between the fiber cable from the line side and the pigtails to be passed to the fiber distribution frame.