OSPF Protocol

OSPF – Open Shortest Path First Protocol

Routers connect networks through IP. OSPF is used to to find the best path for the packets as they pass through a set of connected networks.

OSPF is a Link State Protocol. Link State Protocol exchange the state of their links and the cost associated with it.

OSPF, when configured, will listen to its neighbors and gather all link state data available to build a topology map of all available paths in the network & save this information in the Topology Database.

With this information, it calculates the shortest path using the Dijkstra algorithm.

OSPF Areas:

A number of routers are grouped together into Routing Areas to simplify and optimize resource available resources.

Having multiple routers can flood the network and reduce efficiency. Hence, having resource optimization is especially important for large enterprise systems.

Areas are a logical collection of routers that carry the same Area ID or number inside of an OSPF network, the OSPF network itself can contain multiple areas, the first and main Area is called the backbone area “Area 0”, all other areas must connect to Area 0.