Cisco Certified Network Associate (CCNA) Practice Exam

What is the primary effect of reducing the number of OSPF neighbor adjacencies?

1. Increased route redundancy

2. Decreased CPU load on routers

3. Improved link state update rates

4. Extended OSPF area capabilities

The correct answer is: Decreased CPU load on routers

Reducing the number of OSPF (Open Shortest Path First) neighbor adjacencies primarily leads to a decrease in CPU load on routers. Each OSPF adjacency requires CPU resources for various tasks such as maintaining neighbor relationships, sending and receiving Hello packets, and managing link-state advertisements. With fewer adjacencies, routers can allocate their processing power more efficiently, leading to improved overall performance. In a network with many OSPF neighbors, each additional adjacency increases the amount of control protocol information that needs to be processed. This can result in higher CPU utilization and potential performance degradation. Therefore, minimizing the number of neighbor adjacencies streamlines OSPF operations and conserves CPU resources. While other choices might seem relevant in different contexts, they do not directly relate to the primary consequence of reducing OSPF adjacencies. For instance, route redundancy pertains to the availability of backup paths in a network, which is not directly influenced by the count of OSPF neighbors. Link state update rates are affected by the overall design and health of the OSPF network rather than simply the number of neighbor relationships. Extended OSPF area capabilities deal more with the scalability of the OSPF design rather than adjacency counts alone.