Fortinet Fortigate Administrator FCP Fortigate 76 · Free Practice Question Easy
Question 4
Refer to the exhibit.
Which algorithm does SD-WAN use to distribute traffic that does not match any of the SD-WAN rules?
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A
A. All traffic from a source IP to a destination IP is sent to the same interface.
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B
B. Traffic is sent to the link with the lowest latency.
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C
C. Traffic is distributed based on the number of sessions through each interface.
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D
D. All traffic from a source IP is sent to the same interface.
Reveal correct answer
Correct answer: A
Explanation
A is correct: All traffic from a source IP to a destination IP is sent to the same interface.
Explanation:
In Fortinet SD-WAN, if traffic does not match any explicit SD-WAN rules, the implicit rule (seen at the bottom of the exhibit) takes effect.
The implicit rule uses the "Source-Destination IP" load-balancing algorithm, which means:
All traffic between a specific source IP and specific destination IP is routed through the same interface to maintain session consistency.
This prevents issues where different packets from the same session take different paths, causing potential disruptions.
Why Not the Other Options?
B (Traffic is sent to the link with the lowest latency):
Latency-based selection happens only when a rule specifies latency as a criterion, which is not the case in the implicit rule.
C (Traffic is distributed based on session count):
FortiGate does support session-based load balancing, but this is not the default behavior when no SD-WAN rule matches.
D (All traffic from a source IP is sent to the same interface):
This would mean all connections from a source IP use the same interface, which is incorrect.
The correct scope is source IP to destination IP, not just source IP alone.
Thus, A is the correct answer.
Discussion
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