C H A P T E R 1

Concepts

Figure 1-1Flow of an Open Directory request

Open Directory client

DirectoryServices daemon

Open Directory plug-ins

Request

Response

The Open Directory programming interface identifies the basic features that are common to many directory services and provides the functions necessary to support the development of high-quality applications that can work with a wide range of dissimilar directory services.

Nodes

From the viewpoint of Open Directory, a directory service is a collection of one or more nodes, where a node is a place that can be searched for information. Each NetInfo database in a hierarchy and each LDAP service configured by the Directory Access tool is a separate node. The following rules apply to nodes.

■A node is either the root of a directory or a child of another node.

■A registered node is a node that an Open Directory plug-in has registered with Open Directory or that an administrator has registered using the Directory Access tool.

■A node is a collection of records and child nodes.

■A record can belong only to one node.

■A record has a type and can be of no more than one type. Examples of record types include user records and group records.

■A record has a name and type that together make the record unique within its node. For example, there can’t be two user records that have the name “admin,” but there can be a user record named “admin” and a group record named “admin” within the same node.

■Nodes and records can contain any number of attributes.

■An attribute can have a value. Certain attributes can have more than one value.

■An attribute value is arbitrary data whose structure is unknown to the Open Directory programming interface. Open Directory clients are responsible for interpreting the value of any particular attribute.

Figure 1-2(page 11) shows how Open Directory and the Open Directory LDAPv3 and NetInfo plug-ins might locate nodes over a network.

10Open Directory Overview

2007-01-08 © 2007 Apple Inc. All Rights Reserved.

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Apple OS X manual Nodes, 1Flow of an Open Directory request