This article provides some guidance about how to set up a Microsoft Office Communications Server 2007 R2 federation clearinghouse deployment. The goal of the clearinghouse is to simplify Public IM Connectivity (PIC) (such as AOL, The Microsoft Network (MSN), and Yahoo) with existing on-premise Office Communications Server 2007 R2 deployments. The clearinghouse model also facilitates relationships between member organizations. Companies can federate more easily with each other without setting up explicit pair-wise federation relationships.
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