We pick g.root-servers.net, one of the 13 root servers (1), and ask it about domainforum.de and learn that de is delegated to six name servers (2), so we ask z.nic.de where we learn that domainforum.de is delegated to three name servers, including b.ns14.net (3), so we ask that one and get the following answer:
Domainforum.de is a domain controlled by three domain name servers at ns14.net having a total of six IP numbers. All six of them are on different IP networks. Domainforum.de has one IP number (62.116.130.8).
There are several thousand of domains that use the primary name server a.ns14.net.
Most of those use the four name servers a, b, c and d.ns14.net together, hereafter referred to as "name server group 1", (example: fleischerei-bg.de, csk-media.de and geilefeiertage.com ). Worth noting is that most of the domains that use name server group 1 use the primary name server a.ns14.net.
Three percent of them use the two name servers a and b.ns14.net together (but neither c nor d.ns14.net ), hereafter referred to as "name server group 2", (example: amessage.dk, ewald-wesner.de and toplovelinks.de ). Worth noting is that three quarter of the domains that use name server group 2 use the primary name server a.ns14.net.
The IPv4 number 62.116.130.8 only
There are several thousand of domains that only use the IPv4 number 62.116.130.8.
The four name servers a, b, c and d.ns14.net together
There are several thousand of domains that use name server group 1.
Most of those use the primary name server a.ns14.net (example: seximnetz.com, ach.in and amateurcams.de ). Worth noting is that most of the domains that use the primary name server a.ns14.net use name server group 1.