Examkin

Question

Difficulty: MediumUtilizing Hardware Testers and Packet Analyzers

A network engineer is investigating excessive link degradation and packet loss on a 10GBASE-LR single-mode fiber link connecting two campus buildings spaced 1.2 kilometers apart. An optical power meter confirms that received optical power is 16 dB below expected baseline levels, indicating high attenuation along the path. Which diagnostic tool should the engineer use to identify the precise distance to the macrobend or splice fault causing the signal loss?

  1. Optical Time-Domain Reflectometer (OTDR)Answer
  2. B
    Time-Domain Reflectometer (TDR)
  3. C
    Tone Generator and Probe Kit
  4. D
    Packet Analyzer

Answer

An Optical Time-Domain Reflectometer (OTDR) should be used because it measures light reflections along an optical fiber cable to locate the precise distance to physical faults, splices, and severe attenuation points.
The Optical Time-Domain Reflectometer (OTDR) is specifically designed for optical fiber media. It injects light pulses down the fiber core and measures the time and intensity of light reflected back (Rayleigh backscattering and Fresnel reflections). This allows the tool to display a trace mapping the precise distance to splices, connectors, macrobends, or physical breaks.

Step-by-Step Solution

1
Analyze the physical medium and problem type
The scenario specifies single-mode optical fiber media exhibiting high attenuation (excessive dB loss).
Selecting the correct tester requires identifying whether the medium is copper or fiber.
2
Determine the diagnostic requirement
The technician needs to locate the exact position (distance) of a physical Layer 1 optical fault.
While an optical power meter measures total loss, pinpointing distance to a break or bend requires reflection analysis.
3
Select the appropriate hardware tester
An Optical Time-Domain Reflectometer (OTDR) transmits light pulses into the fiber and calculates fault distances based on return time and light scattering.
OTDR is the industry-standard tool for graphical signature and distance measurement of fiber optic link anomalies.

Key Concept

Fiber Optic Physical Layer Troubleshooting with OTDR
Rate this question

Topics

Utilizing Hardware Testers and Packet Analyzers

More questions from this topic