The concept of the forest trust is introduced in Windows Server 2003 to make deployment of multiple forests easier. Administrators can us a forest trust to federate two Active Directory forests with a single trust relationship to provide a seamless authentication and authorization experience across the forests. This white paper describes common scenarios for deploying forest trusts, basic concepts for forest trusts, and the technologies that are included with Windows Server 2003 that enable multiple forest deployments.

Note
This document refers to features that are included with Windows Server 2003, Standard Edition; Windows Server 2003, Enterprise Edition; and Windows Server 2003, Datacenter Edition. These features are not included with Windows Server 2003, Web Edition.

The scope of this white paper is restricted to concepts about authentication, authorization, and trust management across multiple forests. Although the basic reasons for deploying multiple forests are explained, this white paper is not intended to be a decision guide for multiple forest deployment. Also, this white paper does not discuss how to synchronize Microsoft Outlook address book contacts or Microsoft Exchange Server public folders. This paper does, however, provide information about other technologies, such as Exchange Server public folder replication tools.

For more information about this topic, see Planning and Implementing Federated Forests in Windows Server 2003.