After making decisions about scale, latency targets, and additional DNS based features that will be supported it’s time to define the next level of details.
The DNS is a critical component of ISP infrastructure. It’s usually described in two forms, Authoritative and Caching.
Authoritative DNS Servers host your domains like www.yourcompany.com, and associated resource records, as well as their location. It does this by mapping names of hosts to their IP-addresses.