DNS/nominumについて、ここに記述してください。

http://web.archive.org/web/20140820184513/http://nominum.com/ghosts-in-the-dns-machine/

Nominum’s algorithms for determining what DNS data is stored in the cache will NOT store the DNS data that enables this vulnerability. 

To capture the technical point:
  Vantio never uses authority section data from a zone to update the zone’s delegation entry. 

Or, said another way, Vantio only accepts delegation data from a parent zone.

NSをキャッシュさせる方法は他にもある。