What is Federated Naming?

Federated Naming Service provides a method for hooking up, or federating, multiple naming services under a single, simple uniform interface for the basic naming and directory operations. The service supports resolution of composite names--names that span multiple naming systems--through the naming interface. Each member of a federation has autonomy in its choice of naming conventions, administrative interfaces, and its particular set of operations, other than name resolution.

In the Solaris environment, the FNS implementation consists of a set of enterprise-level naming services with specific policies and conventions for naming organizations, users, hosts, sites, and services, as well as support for global naming services such as DNS and X.500. More specifically, FNS has support for:

• Enterprise-level naming services: NIS+, NIS and files

• Global-level naming services: DNS, and X.500 (over LDAP or DAP). See Solaris Naming Administration Guide for information on DNS Text records and X.500 attribute syntax for XFN references

• Application-specific namespaces: file naming, printer naming

• Generic application namespaces for other applications

What Is XFN?

XFN stands for X/Open Federated Naming. XFN is a standard that is actively supported by organizations such as SunSoft, IBM, Hewlett-Packard, DEC, Siemens, and OSF. The programming interfaces and policies that FNS supports are specified by XFN. An overview of XFN concepts is presented later in this chapter; Chapter 2, Interfaces for Writing XFN Applications describes the XFN programming interface in detail.

In a 64-bit XFN application, the X.500 directory service is not supported.

FNS is compliant with the X/Open CAE Specification for Federated Naming (July 1995). Applications that use FNS are portable across platforms because the interface exported by FNS is XFN, a public, open interface endorsed by other vendors and X/Open. X/Open Co. Ltd. is part of the Open Group, which is an international standards organization committed to defining computing standards that are endorsed and adhered to by major computer vendors.

Why FNS?

FNS is useful for the following reasons:

• A single uniform naming interface is provided to clients for accessing different naming services. As a consequence, the addition of new naming services does not require changes to applications or to existing member naming services. Furthermore, application developers need to learn and use only one naming interface.

• Names can be composed in a uniform way, and the resulting composite names can have any number of components. This allows the composite namespace to serve the needs of many diversed applications.

• Coherent naming is encouraged through the use of shared contexts and shared names. This reduces duplication of effort in individual applications when supplying similar functionality.