The NDS schema consists of two basic components:
Object Classes
Attribute Types
The set of rules that controls the creation of a particular object is called an object class. Each object class is defined in terms of attributes. An attribute is a specific piece of information that exists for an object. (Attributes are called properties by NetWare utilities and documentation.)
For example, NDS contains an object class for users, called User object. This User object class defines many attributes (more than 80), including attributes for such items as the user’s name, telephone number, address, and group memberships.
Attributes are defined in terms of a base set of data types called attribute syntaxes. The attribute syntaxes define the primary data types for values stored in the NDS database.
For example, some attributes such as Password Minimum Length or Minimum Account Balance take integer values while other attributes such as a user's Full Name or Given Name take string values.
NDS has a set of built-in classes and attribute types that accommodate general categories of network objects such as organizations, users, and devices. This set is called the base schema. To this schema, Novell developers have added objects and attributes to form a standard schema for NetWare 5.x. As a developer, you can build on the standard schema to create new classes and new attributes for objects. However, these new classes and attributes must be defined in terms of the existing syntaxes. Defining new syntaxes is not allowed.