What is a key benefit of DNS's hierarchical design?

What is a key benefit of DNS's hierarchical design?

• A. Faster search
• B. More memory usage
• C. Higher error rate
• D. More overhead in routing

Answer: (A)

DNS uses a hierarchical, zone-based structure so lookups don’t have to search a single giant list. The root directs you to the right top-level domain, each domain’s servers tell you where to find its subdomains, and so on. This delegation means queries can be resolved by pulling the exact authority for the needed portion, rather than scanning everything. Plus, results can be cached at recursive resolvers along the way, so subsequent requests for the same name come back even faster. That combination of distributed control and caching is what makes lookups quick and scalable, which is why faster search is the best choice. The other options describe downsides or costs, not benefits.

DNS uses a hierarchical, zone-based structure so lookups don’t have to search a single giant list. The root directs you to the right top-level domain, each domain’s servers tell you where to find its subdomains, and so on. This delegation means queries can be resolved by pulling the exact authority for the needed portion, rather than scanning everything. Plus, results can be cached at recursive resolvers along the way, so subsequent requests for the same name come back even faster. That combination of distributed control and caching is what makes lookups quick and scalable, which is why faster search is the best choice. The other options describe downsides or costs, not benefits.