How DNS Works

DNS translates names such as example.com into records that software can use to establish network connections. A client normally asks a configured resolver rather than querying every DNS server in the hierarchy directly.

The response may include address records, aliases, mail routing, delegation, or other record types depending on the query.

A recursive resolver answers on the client's behalf. When a cached answer is unavailable, the resolver can walk the DNS hierarchy beginning at the root, continue through the relevant top-level domain, and reach the authoritative servers for the requested domain.

The resolver then returns the answer to the client and can cache it for the record's permitted lifetime.

Authoritative name servers publish the records for a DNS zone. Delegation from a parent zone tells resolvers which name servers are responsible for the child domain.

Because delegation, authoritative data, and recursive caches are separate layers, the same domain can temporarily produce different answers at different points in the network.

DNS records carry TTL values that influence how long recursive resolvers may reuse a cached answer. Caching reduces repeated upstream queries and improves performance, but it also means changes are not necessarily visible everywhere immediately.