350-401 Question 62
Select 3A network engineer is designing a QoS policy to ensure that VoIP traffic is prioritized over other types of traffic in a congested network. The engineer wants to ensure the policy includes traffic classification, marking, and queuing mechanisms. Which components of QoS should the engineer implement to achieve this objective?
- A
Traffic Classification
- B
Congestion Avoidance
- C
Traffic Marking
- D
Congestion Management
- E
Policing
Show answer and explanation
Correct answers: A, C, D
Explanation
To ensure VoIP traffic is prioritized, the engineer must use traffic classification to identify VoIP packets, marking to tag these packets for prioritization, and congestion management to implement queuing mechanisms (like LLQ) that prioritize VoIP during congestion. Congestion avoidance and policing, while part of QoS, are not directly required for prioritizing VoIP traffic in this scenario.
- A. Correct.
Traffic classification is used to identify and distinguish different types of traffic, such as VoIP, video, or data. This is a critical first step in implementing QoS policies.
- B. Incorrect.
Congestion avoidance mechanisms, such as Weighted Random Early Detection (WRED), are more focused on avoiding packet drops during congestion rather than prioritizing traffic types, making it less relevant to this scenario.
- C. Correct.
Traffic marking involves tagging packets, such as using DSCP or CoS values, so that network devices can recognize and prioritize the traffic appropriately.
- D. Correct.
Congestion management includes queuing mechanisms such as Low Latency Queuing (LLQ), which can prioritize VoIP traffic over other traffic during congestion.
- E. Incorrect.
Policing is used to enforce traffic rate limits by dropping or re-marking excess traffic. This is not directly related to prioritizing traffic types like VoIP in this scenario.