What is OSPF multi area adjacency?
The OSPFv2 Multiarea Adjacency feature allows you to configure a link on the primary interface to enable optimized routing in multiple areas. Each multiarea interface is announced as a point-to-point unnumbered link. You can only configure multiarea adjacency on an interface that has two OSPF speakers.
What are the features of multi area OSPF?
With multiarea OSPF, one large routing domain can be divided into smaller areas, to support hierarchical routing. Routing still occurs between the areas (interarea routing), while many of the processor intensive routing operations, such as recalculating the database, are kept within an area.
Which two LSA types are generated exclusively by ABRs?
Let me summarize the LSA types for you:
- Type 1 – Router LSA: The Router LSA is generated by each router for each area it is located.
- Type 2 – Network LSA: Network LSAs are generated by the DR.
- Type 3 – Summary LSA: The summary LSA is created by the ABR and flooded into other areas.
What is concept of OSPF area?
By definition an OSPF area is a collection of networks, not a collection of routers. A backbone network segment is an IP subnet that belongs to the area identified by 0.0. 0.0. Areas that are not physically connected to the backbone are logically connected by a backbone ABR using an OSPF virtual link.
What is the difference between backbone area and stub area in OSPF?
The backbone is considered a standard area. Stub areas can contain type 1, 2, and 3 LSAs. A default route is substituted for external routes. Totally stubby areas can only contain type 1 and 2 LSAs, and a single type 3 LSA.
Why is Area 0 backbone area in OSPF?
Albeit OSPF is a link state protocol, the way OSPF handles inter-area traffic leaves it prone to routing loops. This is why OSPF must connect back to area 0 – to avoid routing loops.