The Active Directory Application Mode, or ADAM, is a new Microsoft service that helps organizations add the capabilities of the Active Directory to multiple applications. ADAM is meant to address the problem of maintaining multiple directory services for running individual network functions such as public key authentication, white pages, and different logons. ADAM is a non-operating system service that can run on one or more servers, and can even run as multiple instances on the same server. All versions of Windows Server 2003 plus Windows XP Professional can run ADAM.
Each instance of ADAM is managed as a single entity independent of other instances. Installation is accomplished using the familiar Windows Installer. You can install ADAM from a workstation, even using a scripted installation. ADAM can be turned on and off while your server is running, and developers and applications that make use of ADAM can control ADAM and switch to different instances of ADAM as required.
Microsoft sees ADAM's uses in four main scenarios: application specific directories, as an application developer tool, in extranet access management, and finally in application migration tasks. Typical uses for this service might include a portal storing use personalization information in the AD, exposing directory data to an application without having to alter the current AD schema associated with an organization, and independent management of application data by different groups in an enterprise.
You'll find a white paper describing ADAM at: http://www.microsoft.com/windowsserver2003/techinfo/overview/adam.mspx.
Barrie Sosinsky is president of consulting company Sosinsky and Associates (Medfield MA). He has written extensively on a variety of computer topics. His company specializes in custom software (database and Web related), training and technical documentation.