Exam NSE7_SSE_AR-26 Topic 1 Question 100 Discussion

FortiGate SD-WAN can distribute traffic over multiple WAN links while applying performance-based eligibility checks. These checks measure network conditions such as latency, jitter, and packet loss against defined service-level agreement thresholds.
Option A is correct because FortiGate can load balance sessions across available SD-WAN members that satisfy the configured SLA target. An interface that fails the required performance criteria is excluded from the eligible load-balancing set under normal SLA-compliant operation.
Option B is correct because current FortiOS versions support load balancing within the Lowest Cost (SLA) strategy. The configuration uses set mode sla together with set load-balance enable under the relevant SD- WAN service rule. Importantly, the load-balancing algorithm does not use interface cost to select individual links once SLA-based load balancing is enabled.
Option C is incorrect because Best Quality is a separate strategy that selects preferred members based on measured link-quality metrics. It is not the supported SLA-based multi-link load-balancing configuration described in the question.
Option D is incorrect because the legacy session, spillover, and volume terminology does not describe supported Best Quality load-balancing algorithms in this context.
FortiOS 7.4.1 and later integrated the former Maximize Bandwidth strategy into the current load-balancing configuration model.
References: FortiOS 7.6 Administration Guide - Lowest Cost (SLA) Strategy, Load Balancing with SLA Targets, and SD-WAN Service Rules.