300-420 Question 168
Select 3An enterprise network team is deploying Dense Wavelength Division Multiplexing (DWDM) technology to support high-bandwidth connections between two data centers that are 200 km apart. The team needs to ensure signal integrity and minimize data loss over this distance. Which of the following design considerations are most critical to achieve this goal?
- A
Deploying optical amplifiers at appropriate intervals along the fiber path
- B
Ensuring proper wavelength spacing to avoid signal interference
- C
Using electrical repeaters at every 50 km to regenerate the signal
- D
Implementing Forward Error Correction (FEC) to enhance data recovery
- E
Utilizing multimode fiber cables for long-distance transmission
Show answer and explanation
Correct answers: A, B, D
Explanation
DWDM systems are designed for long-distance, high-bandwidth optical transmissions. To maintain signal integrity over a 200 km distance, it is critical to deploy optical amplifiers, ensure proper wavelength spacing, and implement advanced error correction techniques like FEC. Multimode fiber is unsuitable for such distances, and electrical repeaters are not typically required given the advancements in optical amplification technology.
- A. Correct.
Optical amplifiers (such as EDFA or Raman amplifiers) are essential for boosting the signal strength in long-distance DWDM systems, ensuring signal integrity over spans like 200 km.
- B. Correct.
Proper wavelength spacing is critical in DWDM systems to avoid crosstalk and interference between closely packed optical channels.
- C. Incorrect.
Electrical repeaters are not typically used in modern DWDM systems; optical amplifiers and advanced error correction techniques are preferred for maintaining signal quality.
- D. Correct.
Forward Error Correction (FEC) is a key feature in DWDM systems to detect and correct errors in long-haul transmissions, improving data reliability.
- E. Incorrect.
Multimode fiber is not suitable for long-distance transmissions like 200 km due to its high attenuation and modal dispersion. Single-mode fiber is the appropriate choice for DWDM applications.