Large amounts of information need to be organized in some way to make efficient retrieval possible and ensure that names are unique. Information in the DIB is organized into a hierarchical structure known as the Directory Information Tree (DIT). The structure and naming of the nodes in the DIT are specified by registration authorities for a standardized set of X.500 names and by implementers of the directory service (such as OSF) for implementation-specific names. The DIT hierarchy is described by a schema. Schemas are described in more detail in Schemas.
Although the X.500 standard does not mandate a specific schema, it does make general recommendations. For example, countries and organizations should be named close to the root of the DIT; people, applications, and devices should be named further down in the hierarchy. GDS supplies a default schema that complies with these recommendations.
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Relative Distinguished Names and Attribute Value Assertions