Active Directory is a special-purpose database and is not a registry replacement.
The directory is designed to handle a large number of read and search operations and a significantly smaller number of changes and updates.
Active Directory data is hierarchical, replicated, and extensible. Because it is replicated, you do not want to store dynamic data, such as corporate stock prices or CPU performance. If your data is machine-specific, store the data in the registry.
Typical examples of data stored in the directory include
printer queue data,
user contact data, and
network/computer configuration data.
The Active Directory database consists of objects and attributes. Objects and attribute definitions are stored in the Active Directory schema.
The Active Directory is the foundational networking component in Windows 2000.
The Active Directory completely redesigns Microsoft networking from the days of Windows NT and brings Windows networking to a hierarchical, directory service model. This model modernizes NT and paves the way for the future. With the Active Directory, you have more manageability, more support for network resources, standardized naming, and excellent query capabilities. In short, the Active Directory opens an entire new world for Windows.
A directory is, at its most fundamental level, a collection of information that is organized in a particular way. The organizational method makes sorting through the information fast and easy so you can find the desired data. Directory services are often compared to a phone book. A phone book is a collection of data organized by last name, first name, phone number, city, and state. Because the information is organized in a particular way, you can quickly find a particular person and get his or her telephone number. Directories, of course, are nothing new and have been used for about as long as books have been available; but in terms of networking, directories are still on the cutting edge of networking technology.
It is important to note that the Active Directory namespace is not the DNS namespace.
The DNS namespace is used on the Internet while the Active Directory namespace is used for private networks.
However, the Active Directory namespace is based on DNS, and it connects into the DNS namespace. In other words, DNS is a
global namespace that makes up the entire Internet, and the Active Directory namespace is built on the DNS hierarchical structure so that it connects into the DNS global namespace. For now, it is important to remember that you cannot implement
the Active Directory without DNS, and all Active Directory names are DNS names.