Nokia Certified Network Professional – IP/MPLS Services — Question 25

Which of the following statements is true about chromatic dispersion (CD)?

Answer options

• A. Different channels have different bandwidth and this causes different CD performances.
• B. The fiber attenuation changes along the fiber, and when the light crosses these differences the CD takes place.
• C. Different wavelengths propagate at different speeds within the same media and therefore different colors travel in the fiber with different speed.
• D. The fiber attenuation introduces inter-channel interference.

Correct answer: C

Explanation

The correct answer is C because chromatic dispersion occurs due to the fact that different wavelengths of light travel at different speeds in optical fiber, leading to a spread of colors over time. Options A and B incorrectly attribute CD to bandwidth differences and attenuation variations, while D mischaracterizes the nature of inter-channel interference as being caused by attenuation rather than dispersion.