We pick b.root-servers.net, one of the 13 root servers (1), and ask it about f.am and learn that am is delegated to six name servers (2), so we ask ns-cdn.amnic.net where we learn that f.am is delegated to two name servers, including ns2.sedoparking.com (3), so we ask that one and get the following answer:
F.am is a domain controlled by two domain name servers at sedoparking.com having a total of six IP numbers. Two of them are on the same IP network. F.am has one IP number (82.98.86.172), but the reverse is www172.sedoparking.com.
One percent of them use the two name servers ns1 and ns2.poishi.com together, hereafter referred to as "name server group 2", (example: altavision.ru ).
The IP number 82.98.86.172 only
There are several thousand of host names that point only to the IP number 82.98.86.172.
Most of those use name server group 1 (example: albergo.us, grippe.info and protrans.net ). Worth noting is that five percent of the domains that use name server group 1 point only to the IP number 82.98.86.172.