OSF DCE Application Development Guide--Introduction and Style Guide

Using the DCE Name Service
entries is searched. The entries in this path may themselves be other profiles, or groups,
or simple entries. The search continues until either a compatible binding is found, or the
entire path has been unsuccessfully traversed.
5.12 Three Models for Accessing Binding Information
By adding groups and profiles to the object-specific namespace organization originally
described, you can implement any or all of the following three basic models for
accessing binding information:
• Clients bind to services
• Clients bind to servers
• Clients bind to resources or objects
Each of the three models is described in the following sections.
5.12.1 Access By Services
Servers have separate namespace entries; each server distinguishes the bindings it
exports with its own identifier; that is, an object UUID that it generates for itself the first
time it starts up. These separate server entries are also members of group namespace
entries, which represent services. The criterion for membership in a service group is that
all the servers in it export the interface that identifies that service. (They may happen to
export other interfaces as well.)
Clients, in effect, bind to services by importing their binding handles from the group
entries. Note, however, that the server-specific entries still exist independently and are
accessible to lookup.
This model is appropriate for applications where clients do not care which server they
happen to bind to or where that server is located as long as it offers the desired service.
The eligible servers are pooled into a group entry from which bindings to one of them are
selected in an undefined order and returned whenever a client performs an import
operation from the group entry.
5.12.2 Access By Servers
In this model, distinct servers have separate and distinct name entries, and clients import
bindings directly from the server entries. Hence, an application using this kind of
binding model will own just as many simple entries in the namespace as there are active
servers.
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