The document provides information about using an OTDR (Optical Time Domain Reflectometer) to test fiber optic cabling. It discusses how an OTDR works, generating a baseline trace of a cable link and identifying events. It also covers fault location, different OTDR types, and how to properly configure OTDR settings like range, pulse width, index of refraction, and averaging time to obtain accurate test results. Analysis methods like two-point loss measurements and LSA lines are also summarized.