Viewpoints on the Directory Service
The DCE Directory Service looks very different to the end user, programmer, and administrator. This section takes a brief look at the Directory Service from each of these three
perspectives.
End User's Perspective
The DCE Directory Service is one of the few DCE technologies that is visible to the end user. An end user can use the CDS Browser to look through the cell's namespace. A frequent use of the
namespace is in referencing the file system. The pathname for a file in a foreign cell is partially a pathname in the Directory Service, as in the example /.../cs.univ.edu/fs/usr/ziggy
given previously.
Application Programmer's Perspective
DCE application programmers do not necessarily need to interface directly with the Directory Service, since a frequent use of the Directory Service - to look up the location of a server - can be
done automatically by DCE RPC. Programmers who do use the Directory Service interact with it through the X/Open Directory Service interface. XDS provides facilities for adding, deleting, modifying,
and looking up names and their attributes.
Programmers use XDS for accessing both DCE directory services - CDS and GDS. However, the programmer needs to understand the different types of names used for different namespaces, and be aware of
some XDS calls that are not available when CDS is being used. An example is the search query, which is possible in GDS, but not in CDS.
Administrator's Perspective: Two Directory Services and an Intermediary
Unlike the end user and application programmer, the Directory Service administrator is aware of the cell's directory service configuration, since the two directory services are administered
separately. The administrator manages the CDS server, the Global Directory Agent, and the GDS server, if the cell has one.
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