300-440 Question 103
Single answerA network engineer is configuring OSPF over a Frame Relay network. The network consists of one hub router and three spoke routers. The engineer wants to minimize the number of OSPF adjacencies and avoid any additional overhead by simulating a broadcast network type. Which OSPF network type should the engineer configure on the hub and spoke routers to achieve this?
- A
Point-to-Point
- B
Broadcast
- C
Nonbroadcast
- D
Point-to-Multipoint
Show answer and explanation
Correct answer: C
Explanation
Nonbroadcast is the correct choice because it is designed for environments like Frame Relay where multiple routers share a single physical or logical network. It requires manual neighbor configuration but minimizes OSPF adjacencies and overhead, making it ideal for the described hub-and-spoke topology.
- A. Incorrect.
Point-to-Point is typically used for direct links between two routers, but it does not support multiple routers on a single network segment, which is required for this Frame Relay topology.
- B. Incorrect.
Broadcast simulates Ethernet-like behavior and supports automatic neighbor discovery, but it is not natively supported on Frame Relay networks and would require manual configuration.
- C. Correct.
Nonbroadcast is suitable for Frame Relay networks as it supports multiple routers on a single segment and requires manual neighbor configuration, which minimizes overhead while simulating a broadcast network.
- D. Incorrect.
Point-to-Multipoint treats each connection as a separate point-to-point link, which increases the number of OSPF adjacencies and does not minimize overhead in this scenario.