Directory service

A directory service is a software system that stores, organizes, and provides access to information in a computer operating system's directory.

In software engineering, a directory is a map between names and values. It allows the lookup of named values, similar to a dictionary. As a word in a dictionary may have multiple definitions, a directory service can associate a name with multiple, different pieces of information. Likewise, as a word may have different parts of speech and different definitions, a name in a directory may have many different types of data.

Directories may be very narrow in scope, supporting only a small set of node types and data types, or they may be very broad, supporting an arbitrary or extensible set of types.

Examples:

• In a telephone directory, the nodes are names and the data items are telephone numbers.
• In the DNS the nodes are domain names and the data items are IP addresses (and alias, mail server names, etc.).
• In a directory used by a network operating system, the nodes represent resources that are managed by the OS, including users, computers, printers and other shared resources.

External Links

• Directory service @ Wikipedia