[This is pre-release documentation and subject to change in future releases. This topic's current status is: Milestone-Ready]

Topic Last Modified: 2010-03-25

This topic describes the Microsoft Exchange Server components required to provide Unified Messaging features to Enterprise Voice users, as well as the supported topologies for Exchange Unified Messaging (UM) integration.

Exchange Server Components

To provide the Exchange Unified Messaging (UM) features and services described earlier in this section to Enterprise Voice users in your organization, you must deploy the following Exchange server roles:

  • Unified Messaging Server, which provides a single storage location for e-mail and voice mail. The Unified Messaging Server connects Exchange Server with Communications Server.

  • Hub Transport Server, which routes e-mail messages from the Unified Messaging Server to user mailboxes.

  • Client Access Server, which hosts client protocols, such as Post Office Protocol 3 (POP3), Internet Message Access Protocol 4 (IMAP4), Secure Hypertext Transfer Protocol (HTTPS), Outlook Anywhere, Availability service, and Autodiscover service. The Client Access Server also hosts Web services.

  • Mailbox Server, which hosts user mailboxes.

Supported Topologies

Microsoft Exchange Server and Communications Server 2010 must be deployed in a shared Active Directory Domain Services topology for Exchange UM integration to succeed.

You can deploy Communications Server and Exchange UM in the same forest or multiple forests. If you deploy them in multiple forests, the Exchange integration steps must e performed for each UM forest. Furthermore, if you deploy Communications Server and Exchange UM in different forests, each Exchange forest must be configured to trust the Communications Server forest and each Communications Server forest must be configured to trust each UM forest. In addition to this forest trust, the users’ Exchange UM settings must be set on the user objects in the Communications Server forest.

Communications Server supports the following topologies for Exchange UM integration:

  • Single Forest

  • Single Domain (single forest with a single domain). Communications Server, Exchange, and users all reside in the same domain.

  • Multiple Domain (root domain with one or more child domains). Communications Server, and Exchange servers are deployed in different domains from the domain where you create users. UM servers can be deployed in different domains from the Communications Server pool it supports.

  • Multiple Forest (Resource Forest). Communications Server is deployed in a single forest, users are distributed across multiple forests.