300-410 Question 115
Single answerAn OSPF network consists of Area 0 (backbone area) and Area 1, which is not directly connected to Area 0. You are tasked to establish connectivity between Area 1 and the backbone without redesigning the network. Which solution should you implement?
- A
Configure a virtual link between a router in Area 1 and a router in Area 0.
- B
Redistribute OSPF into BGP to connect Area 1 to Area 0.
- C
Create another physical link to directly connect Area 1 to Area 0.
- D
Configure a virtual link through an intermediary area connecting Area 1 to Area 0.
Show answer and explanation
Correct answer: D
Explanation
A virtual link is used in OSPF to logically connect an area that does not directly attach to the backbone (Area 0). The virtual link must traverse an intermediary area that has a router participating in both Area 0 and the disjointed area. This solution allows logical connectivity to Area 0 without requiring physical topology changes, making it the most appropriate solution in this scenario.
- A. Incorrect.
A virtual link cannot be directly configured between a router in Area 1 and a router in Area 0 unless there is an intermediary area to traverse.
- B. Incorrect.
Redistributing OSPF into BGP is not a valid solution for establishing OSPF area connectivity as it involves a different protocol and does not create an OSPF backbone connection.
- C. Incorrect.
Creating another physical link might solve the connectivity issue, but it requires significant changes to the network topology, which violates the requirement to avoid redesigning the network.
- D. Correct.
Configuring a virtual link through an intermediary area connecting Area 1 to Area 0 is the correct solution, as it allows logical connectivity to the backbone area without physical topology changes.