Hierarchical Design for Large OSPF Networks

ACF

Large OSPF networks use a hierarchical design for several reasons, including:

A. To confine network instability to single areas of the network: A hierarchical OSPF design divides the network into smaller areas, with each area having its own backbone area. This allows network instability or failures to be confined to a single area of the network, reducing the impact on the entire network.

B. To reduce the complexity of router configuration: Hierarchical design allows network administrators to segment the network into smaller, more manageable areas, which simplifies router configuration. It is easier to configure routers that are responsible for a smaller subset of the network.

C. To speed up convergence: A hierarchical design reduces the size of the routing tables on individual routers by dividing the network into smaller areas. This reduces the time it takes for routers to converge and allows for faster network performance.

D. To lower costs by replacing routers with distribution layer switches: This statement is not accurate. Hierarchical design involves the use of routers at different layers of the network, including core, distribution, and access layers.

E. To decrease latency by increasing bandwidth: While hierarchical design can improve network performance, it does not directly increase bandwidth or decrease latency.

F. To reduce routing overhead: Hierarchical design reduces routing overhead by dividing the network into smaller areas, reducing the size of the routing tables on individual routers. This reduces the amount of routing traffic and improves network performance.

In conclusion, a hierarchical design for OSPF networks is essential for managing large and complex networks. It improves network performance, simplifies configuration, and reduces the impact of network failures on the entire network.