OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components
Outlines strategies for using each kind of entry.
• The service model
Describes the service model for defining RPC servers and introduces NSI usage
models intended to guide application developers in assessing how to best use NSI for
a given application.
• The resource model
Describes the resource model for defining RPC servers.
14.3.1 NSIDirectory Service Entries
To store information about RPC servers, interfaces, and objects, NSI defines the
following directory service entries in the namespace: server entries, groups, and
profiles. These directory service entries are CDS objects.
• A server entry is a directory service entry that stores binding information and object
UUIDs for an RPC server.
• A group is a directory service entry that corresponds to one or more RPC servers that
offer one or more RPC interfaces, type of RPC object, or both in common.
• A profile is a directory service entry that defines search paths in a namespace for a
server that offers a particular RPC interface and object.
The use of server entries, groups, and profiles determines how clients view servers. A
server describes itself to its clients by exporting binding information associated with
interfaces and objects to one or more server entries. A group corresponds to servers that
offer a given interface, service, or object. Profiles enable clients to access alternative
directory service entries when searching for an interface or object. Used together, groups
and profiles offer sophisticated ways for RPC applications to maintain and use directory
service data.
14.3.1.1 NSI Attributes
Usually, the distinct server entries, groups, and profiles concepts are adequate for using
NSI. However, the way NSI stores RPC information allows you to combine server
entries, groups, and profiles into a single directory service entry. To store information
about RPC applications in a directory service entry, the RPC directory service interface
defines several RPC-specific directory service attributes, or NSI attributes. NSI
attributes contain information about RPC applications in a directory service entry. The
NSI attributes are as follows:
• NSI binding attribute
The binding attribute stores binding information and interface identifiers (interface
UUID and version numbers) exported to the server entry. This attribute identifies a
directory service entry as a server entry.
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