CCNP® Practical Studies: Routing

Scenario 4-2: Configuring OSPF Summarization

This scenario covers the same network topology shown in Figure 4-4. The aim of any network designer is to use summarization wherever possible. OSPF, as you have seen, has some advanced features to allow summarization. The first method you can apply is intra-area summarization on the backbone Routers R1 and R2. A total of 30 networks (contiguous) exist from 131.108.1.0 to 131.108.31.255.

For the core routers in area 0, namely R1, R2, R3, and R4, which pass on routing information to other core or remote routers, you need to have a more detailed view of the network. This detail is required so you do not perform any summarization on the core network and maintain a full IP routing topology in the core (or ...