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Extending the Active Directory
The Active Directory can be conceptualized as a distributed database. Like other databases, the AD has a schema that defines the tables and fields that make up its internal structure and its contents can be queried directly through LDAP mechanisms and protocols.
The AD as designed was intended to be adaptable by end users in order to take advantage of its distributed nature. Because of this, the AD's schema can be viewed by users and, with the appropriate level of authority, can be modified to incorporate application-specific data. For example, the schema could be modified to incorporate a photograph with each user account.
A Schema Committee exists to review and implement any change requests that are made. Questions about extending the schema can be directed to Howard Gilbert of ITS Technology & Planning.