CompTIA Network+ (N10-006) — Question 11

A network technician has configured a point-to-point interface on a router, however, once the fiber optic cables have been run, the interface will not come up. The technician has cleaned the fiber connectors and used an optical power meter to confirm that light is passing in both directions without excessive loss.
Which of the following is the MOST likely cause?

Answer options

• A. Distance limitation
• B. Wavelength mismatch
• C. cross-talk
• D. EMI
• E. Macro bend

Correct answer: B

Explanation

The correct answer is B, as a wavelength mismatch can prevent the interface from functioning properly even if light is passing through the fiber. Options A, C, D, and E are less likely since the technician has already confirmed that light is present without excessive loss, indicating that distance, cross-talk, EMI, and macro bends are not the primary issues in this scenario.