信息技术 开放系统互连 第1部分：目录：概念、模型和服务概述

[中文适用范围]： 该目录提供了许多应用层标准和电信服务所需的目录功能。它提供的功能包括“用户友好命名”，即可以使用方便人类用户引用的名称来引用对象（尽管并非所有对象都需要具有用户友好名称）；以及“名称到地址映射”，允许对象与其位置之间的动态绑定。 [外文原描述]： 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 available, are quite acceptable. It is a characteristic of the Directory that, except as a consequence of differing access rights or un-propagated updates, the results of directory queries will not be dependent on the identity or location of the inquirer. This characteristic renders the Directory unsuitable for some telecommunication applications, for example some types of routing. For cases where the results are dependent on the identity of the inquirer, access to directory information and updates of the Directory may be denied.