* An optical time-domain reflectometer (OTDR) is a device that can measure the characteristics of an optical fiber, such as its length, attenuation, and splice points12.
* An OTDR works by sending a pulse of light into one end of the fiber and measuring the amount of light that is reflected back at different intervals12.
* By analyzing the reflected light, an OTDR can determine the distance to any faults or breaks in the fiber, as well as the overall quality of the fiber12.
* An OTDR can also provide a graphical representation of the fiber, called a trace, that shows the attenuation and reflection along the fiber12.
* Using an OTDR can reduce repair time because it can quickly and accurately locate the fault point in the fiber, without requiring access to both ends of the fiber12.
* The other options are not suitable for testing fiber optic cables:
* A tone generator and wire map are tools that can test copper cables, such as twisted-pair or
* coaxial cables, by sending an electrical signal and identifying the wire pairs3. They cannot test fiber optic cables, which use light instead of electricity1.
* A multimeter is a device that can measure electrical properties, such as voltage, current, and resistance4. It cannot test fiber optic cables, which do not carry electrical signals1.
* A spectrum analyzer is a device that can measure the frequency and amplitude of electromagnetic signals, such as radio waves or light waves5. It can be used to test the wavelength and power of the light source in a fiber optic cable, but it cannot measure the length or quality of the fiber1.
References:
* 1: Optical Fiber - N10-008 CompTIA Network+ : 1.3
* 2: CompTIA Network+ N10-008 Full Course for Beginners - Fiber Optic Cabling and Connectors
* 3: Wire Crimpers and Testers - N10-008 CompTIA Network+ : 1.3
* 4: Multimeter - N10-008 CompTIA Network+ : 1.3
* 5: Spectrum Analyzer - N10-008 CompTIA Network+ : 1.3