300-415 Question 270
Single answerAn enterprise is deploying an SD-WAN solution and wants to implement Quality of Service (QoS) policies to prioritize critical applications over less critical traffic. To ensure appropriate handling, the network administrator configures traffic marking on the vEdge devices. Which of the following statements best describes how marking works in Cisco SD-WAN?
- A
Marking allows the vEdge to classify and modify the DSCP or IP Precedence values of traffic before forwarding it.
- B
Marking is performed only on traffic sourced from the vEdge itself, not on transit traffic.
- C
Marking is only used to match traffic for QoS policies and cannot modify DSCP values.
- D
Marking in SD-WAN is handled exclusively by centralized control policies and not by vEdge devices.
Show answer and explanation
Correct answer: A
Explanation
Marking in Cisco SD-WAN allows vEdge devices to classify traffic and modify QoS-related fields such as DSCP or IP Precedence values. This ensures that traffic is marked correctly for prioritization as it traverses the network. While centralized control policies can define traffic classification criteria, marking itself is carried out at the vEdge level to apply QoS locally.
- A. Correct.
Correct. In Cisco SD-WAN, marking allows the vEdge device to classify traffic and modify the DSCP or IP Precedence values as needed before forwarding it to ensure prioritization in downstream devices.
- B. Incorrect.
Incorrect. Marking applies to both transit traffic and traffic sourced from the vEdge. This prevents congestion and ensures prioritization based on policy.
- C. Incorrect.
Incorrect. Marking in SD-WAN not only matches traffic but also enables the modification of DSCP values to reflect the desired QoS treatment.
- D. Incorrect.
Incorrect. Marking is performed at the vEdge level using local policies, although centralized control policies can influence traffic classification and prioritization.