CodeHS The Internet Practice Test 2026 - Free Practice Questions and Study Guide

After memory or local cache miss, the next move is to locate where the domain’s information lives by asking a root DNS server. The root server doesn’t know the exact IP for the domain, but it provides a referral to the appropriate top-level domain (TLD) server (like the .com or .org server). From there, the resolver asks the TLD server, which then points to the domain’s authoritative server that actually holds the IP address.

So why not ask a TLD server directly? Because you need a pointer to the correct TLD first, and that pointer comes from the root server. Why not save in cache yet? Caching happens after you obtain the IP address; you don’t cache something you don’t yet have. And asking a hosting server isn’t the right step because hosting servers aren’t the authoritative sources for DNS records.