How does OSPF determine the best path through the network?

OSPF (Open Shortest Path First) uses a link-state routing protocol and determines the best path through the network by selecting paths based on the lowest cost. In OSPF, the cost is determined by the bandwidth of the links—the higher the bandwidth, the lower the cost. OSPF assigns a metric to each link, which is usually calculated as the inverse of the bandwidth (where higher bandwidth results in a lower metric), and it uses this information when calculating the best route to each destination.

When OSPF routers exchange link-state advertisements (LSAs), they create a complete map of the network topology. From this map, each router runs the Dijkstra's shortest path first algorithm. This algorithm identifies the least-cost path to each destination based on the cumulative cost of traversing the links in the network. Therefore, OSPF ensures that data packets travel through the most efficient path available, optimizing overall network performance.

Other methods such as the Bellman-Ford algorithm are not utilized in OSPF; rather, that algorithm is more commonly associated with distance-vector protocols. Weighted metrics and per-hop behavior represent concepts used in different contexts that do not align specifically with how OSPF calculates paths.