300-420 Question 14
Select 3You are designing an EIGRP-based routing architecture for a global enterprise network. The topology includes a mix of high-speed WAN links and low-speed satellite links connecting branches. The design must ensure stability, security, and scalability for the routing domain. Which combination of design considerations would best address these requirements?
- A
Use EIGRP stub configuration at branch routers to limit unnecessary routing updates.
- B
Enable EIGRP authentication to secure routing updates between neighbors.
- C
Set the EIGRP Hello and Hold timers to the same values across all links to ensure uniform convergence behavior.
- D
Leverage route summarization at key aggregation points to reduce the size of the EIGRP topology table.
- E
Disable split horizon on all interfaces to improve routing information distribution.
Show answer and explanation
Correct answers: A, B, D
Explanation
To design a stable, secure, and scalable EIGRP network, it is best to use EIGRP stub configurations to limit unnecessary updates, enable authentication to secure routing information, and implement route summarization to reduce the size of routing tables. These steps collectively address the stability, security, and scalability requirements of the routing design. Uniform Hello and Hold timers across links with varying speeds are not recommended, and disabling split horizon indiscriminately can lead to routing loops, which negatively impacts network stability.
- A. Correct.
Using EIGRP stub configuration at branch routers prevents unnecessary routing updates from being propagated to less critical areas, improving stability and scalability.
- B. Correct.
Enabling EIGRP authentication secures routing updates, preventing potential malicious route injection or neighbor spoofing.
- C. Incorrect.
Setting the EIGRP Hello and Hold timers uniformly across all links can lead to suboptimal performance in networks with links of varying speeds, as satellite links may require longer timers.
- D. Correct.
Route summarization reduces the size of the EIGRP topology table and improves scalability by minimizing the number of routes propagated through the network.
- E. Incorrect.
Disabling split horizon on all interfaces can introduce routing loops in the network, which reduces stability and is not recommended.