CCNP / CCDP Routing (Building
Scalable Cisco Networks)/ BSCI (Building Scalable Cisco Internetworks) Exam
Exam Code 642-801
Q7. Which of the following statements is true in multiple OSPF areas environment?
A. ASBR is responsible for redistribution (import) of routing
information in an OSPF network.
B. ABRs have all interfaces in the same area.
C. Internal routers are responsible for routing information redistribution (import).
D. In a multi-area OSPF network, Area 0 may or may not be present.
The following are the types of OSPF routers:
1. Internal router: An internal router has all the interfaces in the same area. All internal routers have same link state databases.
2. Backbone router: Backbone routers sit on the perimeter of Area 0, with at least one interface connected to backbone (Area 0).
3. Area Border Router (ABR): ABRs are routers that have interfaces attached to multiple areas. It may be noted that these routers maintain separate link-state databases for each area that they are connected. They are capable of routing traffic destined for or arriving from other areas.
4. Autonomous System Boundary Router (ASBR): These are the routers that have at least one interface to the external network (another autonomous system). This autonomous network can be non-OSPF. ASBRs are capable of route redistribution, a term used to imply that the concerned router can import routing information from non-OSPF networks and distribute the same in OSPF network for which it is responsible and visa versa.