Active Directory Application Mode

 Active Directory Application Mode (ADAM) is a new mode of the Active Directory directory service that is designed to meet the specific needs of organizations that use directory-enabled applications. While Active Directory supports directory-enabled applications, as well as the server operating system, some directory-enabled applications have requirements that Active Directory does not meet. For example, some directory-enabled applications require schema changes that administrators may not want to make to Active Directory.

In addition, organizations may want to:

•	Support directory-enabled applications but not implement Active Directory domains and forests.
•	Support directory-enabled applications outside their existing domains and forests.
•	Use X.500 naming conventions for top-level directory partitions.
•	Run multiple directory service instances on a single server.

ADAM is designed to support these and other directory service scenarios. ADAM runs completely independently from Active Directory, and ADAM has its own schema. You can make changes to the ADAM schema with no impact to the Active Directory schema. ADAM does not require the presence of Active Directory domain controllers, domains, or forests. Therefore, organizations that have not implemented Active Directory can install and run ADAM. ADAM supports X.500 naming conventions for top-level directory partitions, and you can run multiple instances of ADAM on a single server.
ADAM runs on the following:

•	Domain controllers running operating systems in the Microsoft Windows Server 2003 family (Note that Microsoft Windows Server 2003, Web Edition cannot be a domain controller.)
•	Member servers running operating systems in the Windows Server 2003 family (except for Windows Server 2003, Web Edition)
•	Client computers running Microsoft Windows XP Professional