Nevertheless, the operating system does have a list of features that could be considerably important to your company, features that help you to accomplish business goals more effectively, efficiently, and inexpensively. Active Directory is Microsoft's first real Directory Services offering. Directory Services can offer significant administrative benefits and ease of access to network resources to users and applications. In a Directory Services network environment, each resource on the network is referenced as an object in a hierarchical tree, which is called a directory. Users who need access to these resources can reference them quickly and easily without worrying about their physical location within the enterprise.
Administrators can manage resources effectively from a single location.
The directory hierarchy makes it easy to locate resources, and helps to simplify the processes of adds, moves, and changes. Clustering helps ensure high availability of servers by enabling you to group pairs of servers together as a single logical unit. If a failure occurs on one of the servers in the cluster, the other server takes over for the failed system. This fail-over process can be configured to occur not only when the server hardware fails, but also for application or service failures as well. Clustering was offered under Windows NT 4.0, and has been enhanced under Windows 2000.