300-420 Question 2
Single answerA large enterprise network is implementing a hierarchical addressing scheme to optimize routing performance and reduce the size of routing tables. The goal is to ensure that branch offices can be summarized at the aggregation layer while maintaining connectivity to the core. Which design principle should be followed to achieve this goal?
- A
Use Variable Length Subnet Masking (VLSM) to allocate IP addresses based on each branch office's requirements.
- B
Assign overlapping IP address ranges to branch offices to simplify summarization.
- C
Design the IP addressing scheme to align with the physical topology and use contiguous address blocks for summarization.
- D
Deploy a flat IP addressing scheme to ensure consistency across all devices in the network.
Show answer and explanation
Correct answer: C
Explanation
To achieve efficient route summarization at the aggregation layer, the IP addressing scheme must align with the physical network topology and use contiguous address blocks. This approach allows branch office routes to be summarized effectively, reducing the size of routing tables and enhancing network performance.
- A. Incorrect.
This is a good practice for efficient IP address allocation, but it does not directly address summarization or routing table optimization. VLSM alone cannot ensure summarization at the aggregation layer.
- B. Incorrect.
Assigning overlapping IP address ranges would cause routing conflicts and disrupt network connectivity. This violates fundamental IP addressing principles.
- C. Correct.
Designing the IP addressing scheme to align with the physical topology and using contiguous address blocks enables effective route summarization. This approach reduces routing table size and simplifies network management.
- D. Incorrect.
A flat IP addressing scheme does not allow for summarization, which would result in larger routing tables and inefficient routing in large-scale networks.