• Identity life cycle manager—One of the following supported identity life cycle managers must be deployed.
  
  
  • Microsoft Forefront Identity Manager 2010
    
    
  • Microsoft Identity Lifecycle Manager 2007 FP1
    
    
  • Microsoft Identity Integration Server 2003 SP2
    
    

  Important:
  If Microsoft Identity Integration Server 2003 is deployed, it must be Microsoft Identity Integration Server 2003 SP2.

• Lync Server deployed in your central forest—If you have not deployed Lync Server, see the Lync Server 2010 Planning documentation at http://go.microsoft.com/fwlink/?LinkId=212598 and the Lync Server 2010 Deployment documentation at http://go.microsoft.com/fwlink/?LinkId=206142.
  
  

The central forest can be an existing forest that hosts existing servers running Lync Server, users, groups, contacts, or you can create an entirely new forest.

The central forest should ordinarily be the one that hosts the largest number of users. Connectivity between the central forest and other forests should also be highly available.

Note:
You must establish a two-way trust between the central forest and user forests to enable distribution group expansion when groups from user forests are synchronized as contacts to the central forest.

After you have deployed Lync Server in the central forest, complete the following steps:

• Step 1: Configuring the Identity Life Cycle Manager Server for Lync Server 2010
  
  
• Step 2: Enabling Contacts for Lync Server 2010