SD-WAN-ENGINEER practice question 3 of 15

What is the default action for real-time media applications if link performance is poor?

Full set: 86 questions
Answer options
A: Drop the flow.
B: Move flows. Correct answer
C: Apply Forward Error Correction (FEC).1
D: Raise an alarm.
Correct Answer:
B. Move flows.
Explanation

Palo Alto Networks Prisma SD-WAN continuously monitors the performance of all available paths using metrics like latency, jitter, and packet loss. For real-time media applications, which are highly sensitive to these conditions, an application policy defines the maximum tolerable thresholds. If the currently used link's performance degrades and breaches these thresholds (becoming "poor"), the default and primary corrective action is to seamlessly and non-disruptively move the application flow to an alternate link that is currently meeting the policy requirements. This ensures the application's performance and the user experience are maintained.

Why Incorrect

A. Drop the flow. This is a failure condition that SD-WAN actively works to prevent. Dropping the flow is a last resort if no compliant paths are available, not a default corrective action.
C. Apply Forward Error Correction (FEC). FEC is a configurable link optimization feature used to proactively mitigate packet loss on a path. It is not a default, reactive action triggered by general poor performance.
D. Raise an alarm. Raising an alarm is a monitoring and notification function that occurs in response to poor performance, but it is not the action taken on the traffic flow itself to remediate the issue.

References

1. Palo Alto Networks Prisma SD-WAN Administrator's Guide 6.2: In the section "Path and Application Policies," the guide explains the core logic: "Prisma SD-WAN uses policies to select the best path for an application... If the path quality degrades and no longer meets the policy requirements, Prisma SD-WAN automatically and seamlessly moves the application to a path that does meet the policy requirements." This directly describes the action of moving flows.

2. Palo Alto Networks Prisma SD-WAN Administrator's Guide 6.2: The "Forward Error Correction" section details FEC as a feature that can be enabled on circuit categories to improve performance over links with high packet loss. This confirms it is a configured optimization rather than a default reactive measure. The text states, "You can enable Forward Error Correction (FEC) on circuits to mitigate packet loss for real-time, transactional, and critical application traffic." This shows it's an explicit configuration choice.

Scroll to Top