Topic Last Modified: 2012-09-21
The Lync Server 2013 ExUM Routing application supports integration with Exchange Unified Messaging (UM) in an on-premises environment, where Lync Server 2013 and Exchange UM are both installed locally within your enterprise, or in with Exchange UM hosted by a service provider, as shown in the following diagram.
The following modes are supported:
On-premises Mode Lync Server 2013 and Exchange UM are both deployed on local servers within your enterprise.
Cross-premises Mode Lync Server 2013 is deployed on local servers within your enterprise and Exchange UM is hosted in an online service provider’s facility, such as a Microsoft Exchange Online data center.
Mixed Mode Your Lync Server 2013 deployment has some user mailboxes homed on local servers running Microsoft Exchange Server within your enterprise and some mailboxes homed in a hosted Exchange service data center.
Note: Mixed mode can be used as a transitional solution during evaluation and stepwise migration of users to hosted Exchange UM, or as a permanent solution if you opt to keep some users’ Exchange UM services on-premises after migrating others.
To integrate Lync Server 2013 with hosted Exchange UM, you must configure a shared SIP address space (also called a split domain). In this configuration, both Lync Server 2013 and the third-party hosted Exchange UM service provider can access the same SIP domain address space. For details, see Hosted Exchange UM Integration Architecture in the Planning documentation.