Controlling OSPF Routing Information

Changing OSPF routing policy through the configuration of routing information can meet the requirements in complicated networks. In addition, the advertising and receiving of OSPF routing information can be controlled and the routes of other protocols can be imported.

Configuring ABR Route Aggregation: You can configure the ABR route aggregation to convert the routes with the same prefix to one Type-3 LSA on the ABR and send it to other areas.

Configuring ASBR Route Aggregation: You can configure the ASBR route aggregation to convert the routes with the same prefix to one route on the ASBR and send the route to other ASs.

Configuring OSPF to Filter Routes Received by OSPF: By configuring filtering conditions for the received routes, you can allow only the routes that meet the filtering conditions to be added to the routing table.

Configuring OSPF to Filter ABR Type3 LSA: Filtering LSAs in an area can prevent unnecessary LSA transmission. This reduces the size of the LSDB on the neighboring router and speeds up network convergence.

Configuring OSPF to Import Routes of Other Protocols: If both OSPF and other routing protocols run on the router, you can configure OSPF to import routes generated by other protocols such as RIP, ISIS, BGP, static routes, and direct routes, and then advertise these routes through Type5 LSA or Type7 LSA.

Configuring OSPF to Import a Default Route: The default route is widely applied on the OSPF network to reduce routing entries in the routing table and filter specific routing information.

Configuring the Related Parameters for OSPF to Import Routes: In certain cases, when OSPF imports external routes, the default values of certain additional parameters should be added.