350-401 Question 451
Single answerIn an OSPF deployment within a multi-area network, which router type is responsible for disseminating inter-area routes between Area 0 and other OSPF areas?
- A
Internal router
- B
Backbone router
- C
Area Border Router (ABR)
- D
Autonomous System Boundary Router (ASBR)
Show answer and explanation
Correct answer: C
Explanation
In an OSPF multi-area topology, an Area Border Router (ABR) serves as the key router type for inter-area communication. It connects the backbone area (Area 0) to other areas and ensures that routes are properly disseminated between them. This contrasts with ASBR, which introduces external routes, and internal routers, which operate entirely within a single area.
- A. Incorrect.
An internal router resides entirely within a single OSPF area and cannot disseminate routes between areas.
- B. Incorrect.
A backbone router is any router within Area 0, but not all backbone routers are responsible for inter-area route dissemination.
- C. Correct.
An Area Border Router (ABR) connects two or more OSPF areas and is responsible for distributing inter-area routes between Area 0 (backbone area) and other areas.
- D. Incorrect.
An Autonomous System Boundary Router (ASBR) is responsible for injecting external routes into the OSPF domain, not inter-area route dissemination.