1. Root Servers:
Root servers are positioned at the top or root of the DNS hierarchy, and maintain data about each of the top-level zones. The root servers are maintained by the NIC and have been moved to a common domain for consistent naming purposes. The root servers are named as A.root-servers.net., B.root-servers.net., and so on.
This file is obtained from : ftp://ftp.rs.internic.net/domain/named.root Full Story