CSA - CAN/CSA-ISO/IEC-9594-1
Information Technology - Open Systems Interconnection - the Directory: Overview of Concepts, Models and Services
|Publication Date:||1 February 1997|
The Directory provides the directory capabilities required by OS1 applications, OS1 management processes. other OS1 layer entities, and telecommunications 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 OS1 networks, for example, to be "self-configuring" in the sense that addition, removal and the changes of object location do not affect OS1 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 communications 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 unpropagated 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 telecommunications applications, for example some types of routing.