Networking & Internet
OSPF
Definition
Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single autonomous system (AS).
Why It Matters
OSPF is one of the most widely used interior gateway protocols in large enterprise networks. It allows routers within a single company's network to learn about the network's topology and calculate the most efficient routes for traffic.
Contextual Example
In a large corporate network with multiple routers and interconnected offices, OSPF runs on all routers. If a network link between two offices goes down, OSPF automatically detects the change and the routers recalculate the best alternative path for traffic.
Common Misunderstandings
- OSPF is an "interior" protocol used within a network. BGP is an "exterior" protocol used between networks.
- It is a "link state" protocol, meaning every router has a complete map of the network topology.