We pick h.root-servers.net, one of the 13 root servers (1), and ask it about j.kobegakuin.ac.jp and learn that jp is delegated to seven name servers (2), so we ask g.dns.jp where we learn that kobegakuin.ac.jp is delegated to five name servers, including sigw.sinet.ad.jp (3), so we ask that one and learn that j.kobegakuin.ac.jp is delegated to four name servers (4), so we ask tp01.kobegakuin.ac.jp and get the following answer:
J.kobegakuin.ac.jp is a domain controlled by five domain name servers at kobegakuin.ac.jp and ad.jp having a total of six IP numbers. Some of them are on the same IP network. Incoming mail for j.kobegakuin.ac.jp is handled by two mail servers at kobegakuin.ac.jp. Both are on different IP networks.