300-420 Question 260
Single answerYour organization is deploying a new video conferencing application that requires low latency and minimal jitter. The network is already experiencing congestion during peak hours. As the network designer, which queuing mechanism would be the most appropriate to ensure the video conferencing traffic receives priority while still allowing other traffic to be processed fairly?
- A
Weighted Fair Queuing (WFQ)
- B
Priority Queuing (PQ)
- C
Class-Based Weighted Fair Queuing (CBWFQ)
- D
Low Latency Queuing (LLQ)
Show answer and explanation
Correct answer: D
Explanation
Low Latency Queuing (LLQ) is the most suitable mechanism for this scenario because it provides a strict priority queue for latency-sensitive traffic like video conferencing, ensuring low latency and minimal jitter. At the same time, it prevents other traffic from being starved by combining with CBWFQ for fair bandwidth allocation among non-priority traffic.
- A. Incorrect.
WFQ provides fair queuing by allocating bandwidth among all flows based on weights but does not guarantee low latency for specific traffic like video conferencing.
- B. Incorrect.
PQ ensures that high-priority traffic is transmitted first but can starve lower-priority traffic during congestion, which might not be ideal for a mixed traffic environment.
- C. Incorrect.
CBWFQ allows bandwidth allocation per class of traffic but does not provide strict priority for latency-sensitive applications like video conferencing.
- D. Correct.
LLQ combines strict priority queuing for latency-sensitive traffic with CBWFQ for other traffic, ensuring low latency for video conferencing while avoiding starvation of other traffic.