What are the different types of DNS servers?
All DNS servers fall into one of four categories: recursive resolvers, root nameservers, TLD nameservers, and authoritative nameservers.
What is a DNS recursive resolver?
A recursive resolver acts as a middleman between a client and a DNS nameserver. After receiving a DNS query from a web client, it will either respond with cached data or send requests through the DNS hierarchy until it resolves the domain.
What is a DNS root nameserver?
The 13 DNS root nameservers are known to every recursive resolver. A root server accepts a resolver's query and directs it to a TLD nameserver based on the domain extension (.com, .net, .org, etc.).
What is a TLD nameserver?
A TLD nameserver maintains information for all domain names sharing a common extension. For example, a .com TLD nameserver contains information for every website ending in '.com'.
What is an authoritative DNS server?
The authoritative nameserver is the last stop in a DNS query. It contains the actual DNS records for the domain and provides the resolver with the IP address found in the DNS A record.