Information technology - Open systems interconnection - Part 1: The Directory: Overview of concepts, models and services

This document provides the directory capabilities required by many application layer standards and telecommunication services. Among the capabilities which it provides are those of "user-friendly naming", whereby objects can be referred to by names which are suitable for citing by human users (though not all objects need have user-friendly names); and "name-to-address mapping" which allows the binding between objects and their locations to be dynamic. The latter capability allows networks, for example, to be "self-configuring" in the sense that addition, removal and the changes of object location do not affect network operation.

The Directory is not intended to be a general-purpose database system, although it may be built on such systems. It is assumed, for instance, that, as is typical with communication directories, there is a considerably higher frequency of "queries" than of updates. The rate of updates is expected to be governed by the dynamics of people and organizations, rather than, for example, the dynamics of networks. There is also no need for instantaneous global commitment of updates; transient conditions, where both old and new versions of the same information are a