300-415 Question 258
Single answerA network administrator is configuring queuing policies on a Cisco SD-WAN edge router to prioritize voice traffic over bulk data traffic during network congestion. The policy must ensure that voice traffic receives the highest priority while other traffic is handled fairly. Which queuing mechanism is the most appropriate to implement in this scenario?
- A
Low Latency Queuing (LLQ)
- B
Weighted Fair Queuing (WFQ)
- C
Priority Queuing (PQ)
- D
Class-Based Weighted Fair Queuing (CBWFQ)
Show answer and explanation
Correct answer: A
Explanation
Low Latency Queuing (LLQ) combines the benefits of strict priority queuing with the fairness of class-based queuing, making it the optimal choice for ensuring voice traffic is prioritized while other traffic is handled fairly during congestion. This behavior aligns with the requirements of the scenario.
- A. Correct.
Low Latency Queuing (LLQ) is the correct choice because it allows the administrator to allocate strict priority queues for real-time traffic like voice while ensuring that other traffic is still processed fairly, making it ideal for prioritizing voice traffic in this scenario.
- B. Incorrect.
Weighted Fair Queuing (WFQ) is not ideal for prioritizing voice traffic because it does not provide strict priority for any specific traffic class. Instead, it fairly distributes bandwidth among all flows.
- C. Incorrect.
Priority Queuing (PQ) provides strict priority for certain traffic, but it does not handle other traffic fairly, which could lead to starvation of lower-priority traffic during congestion.
- D. Incorrect.
Class-Based Weighted Fair Queuing (CBWFQ) is useful for traffic classification and fair bandwidth distribution but lacks the strict priority needed for real-time traffic like voice.