By the time we're done with this chapter, you will understand how queries are formed and why they matter.
You will know how those queries originate from a resolver and find their way to the ultimate authoritative nameserver that will send back the response, and you will understand how nameservers are selected in the course of a query/response cycle.
Then, we'll look inside those queries so that you can see what the contents of those queries mean.
In this chapter, we will look at:
- Top-level domain nameservers (DNS)
- Nameserver order
- The anatomy of a DNS lookup
- When DNS uses TCP instead of UDP
- How nameserver selection works
Let's start at the top of the DNS tree.
