Inside the Name Space Directory services have been around for several years, mainly in the enterprise environment. A directory service allows you to more easily manage your network resources. Basically, a directory service maps the names of network resources to their respective network addresses. This enables a user to find a network resource by simply knowing its name. The user doesn't have to know the resource's address or its physical location on the network.
Applications can also use a directory service's database.
For example, an email application can use a directory service database for names and addresses. A directory service also defines the naming structure, or name space , for the network. A naming structure is a set of rules that specifies how all network resources are named and identified. The rules ensure that each entity has a unique name and that no names are identical. The directory service maintains a correspondence between each network name and address.