CompTIA Network+ Practice Test

When does load balancing occur in OSPF?

1. When all routes have a different metric

2. When costs are identical

3. When there is only one route available

4. It never occurs in OSPF

The correct answer is: When costs are identical

Load balancing in OSPF (Open Shortest Path First) occurs when multiple routes to the same destination have the same cost or metric. OSPF uses a cost metric based on the bandwidth of the links; when two or more routes to the same destination have equal costs, OSPF can utilize all of these paths for routing traffic. This process distributes the traffic across the available paths, optimizing network resource usage and enhancing redundancy. In situations where there is only a single route available or when all the routes have different metrics, OSPF does not engage in load balancing. Therefore, when OSPF detects that multiple routes to a destination have identical costs, it employs these routes in a balanced manner, ensuring efficient traffic management across multiple paths.