Active Directory(redirected from NT Directory Service)
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Active Directory(operating system)
Active DirectoryAn advanced, hierarchical network directory service that comes with Windows servers and used for managing permissions and user access to network resources. Introduced in Windows 2000, Active Directory is a domain-based network that is structured like the Internet's Domain Naming System (DNS). Using the LDAP directory access protocol, a company's workgroups (departments, sections, offices, etc.) are assigned domain names similar to Web addresses, and any LDAP-compliant Windows, Mac, Unix or Linux client can access them.
Active Directory can function in a heterogeneous, enterprise network and encompass other directories including NDS and NIS+. Cisco supports Active Directory in its IOS router operating system. See domain-based network, LDAP, forests and trees, Internet domain name, ADSI and network directory.