Overview of Exchange Server 2013 and AD DS Partitions Integration

          For make sure Active Directory components in relation to computers that are running Exchange Server, you must understand how Exchange Server 2013 communicates with AD DS and uses Active Directory information to function. AD DS stores most Exchange Server 2013 configuration information.

Forests: An Exchange Server organization and an Active Directory forest have a one-to-one relationship. You cannot have an Exchange Server organization that spans multiple Active Directory forests. You also cannot have multiple Exchange Server organizations within a single Active Directory forest.

Schema Partition: The Exchange Server 2013 installation process modifies the schema partition to enable the creation of Exchange Server-specific objects. The installation process also adds Exchange Server-specific attributes to existing objects. For example, the installation process updates user objects with additional attributes to describe storage quotas and mailbox features.

Configuration Partition: Stores configuration information for the Exchange Server 2013 organization. AD DS replicates the configuration partition among all domain controllers in the forest,
configuration of the Exchange Server 2013 organization replicates throughout the forest.
Its includes Exchange Server configuration objects, such as global settings, email address policies, transport rules, and address lists.

Domain Partition: Holds information about recipient objects. That includes mailbox-enabled users,
and mail-enabled users, groups, and contacts. Objects that are mailbox-enabled or mail-enabled have
preconfigured attributes, such as email addresses.

Global Catalog: Store the email attributes for mail-enabled and mailbox-enabled objects by replicate when installation. Exchange Server 2013 transport service access the global catalog to find the location of a recipient mailbox when delivering messages.
Client Access servers access the global catalog server to locate the user Mailbox server and to display
the global address list to Microsoft Office Outlook, Microsoft® Outlook Web App, or Exchange
ActiveSync clients.