OSPF (Open Shortest Path First) is a dynamic routing protocol that uses the shortest path algorithm to determine the best route to a destination.
- Automatic route updates
- Fast convergence
- Scales well in large networks
- Vendor-neutral protocol
OSPF is a link-state protocol, meaning routers share information about their links and build a complete network topology.
OSPF uses cost as its metric. Cost is calculated based on bandwidth — lower cost paths are preferred.
- Area 0 – Backbone Area
- Other areas connect to Area 0
- Improves scalability & performance
In multi-access networks, OSPF elects a Designated Router (DR) and Backup Designated Router (BDR) to reduce traffic.
OSPF is commonly used in enterprise networks, data centers, hospitals, and ISPs where fast and reliable routing is required.