DNS Flow from DNSsimple.com

  • Browser Browser cache
  • Browser OS
  • OS OS cache2
  • OS Resolver (ISP)
  • Resolver Root
  • Resolver TLD server addr Root
  • Resolver TLD server
  • Resolver Authorative Server addr (nameservers) < TLD server
  • Resolver IP addr < Authorative server addr

The domain registrars reserves the name and communicates with TLD servers

FQDN - http://api.www.example.com. . Root com. TLD example.com. SLD (Second Level Domain) or Authorative server www.example.com. Sub Domain api.www.example.com. FQDN http://api.www.example.com. URL