active directory service (Microsoft) (ADS)

Active Directory Service(ADS) is a directory service from Microsoft. The ADS service was developed along the lines of X.500 and introduced with the Windows 200 server.

Active Directory Service (ADS) is based on the Lightweight Directory Access Protocol ( LDAP), works with the Domain NameSystem( DNS) for address storage and Kerberos for authentication. The DNS database stores information about network services and the mapping of the complete domain address, the Fully Qualified Domain Name( FQDN), to IP addresses. In the Active Directory( AD) all relevant data ofusers, computers, resources, networks, peripheral devices etc. are stored.

The domain is the basic unit of the Active Directory. In it, the resources and the users are grouped together. The domains are hierarchically structured in a tree structure, the so-called ADS tree, so that all network resources are visible to all domains included in the ADS tree. If two or more ADS trees are joined together, this is referred to as a forest. In ADS services, an Organizational Unit( OU) forms an object for managing resources. This allows the network administrator to manage Windows clients, print servers, file servers or application servers and to use the AD services without having to operate his own domain controllers.