Node names contain addressing data that is used when an application on
 one node needs to connect to an application on another named node.
 These names must be unique within the directory service.

 Some directory services support hierarchical naming.  The names at the
 various levels of the hierarchy, except for the lowest level, are
 commonly referred to as "directories".  The names at the lowest level
 identify the specific node within that part of the hierarchy, and
 contain the node's addressing information.  For these directory
 services, it is the entire hierarchical name that must be unique.