Microsoft Office Communications Server 2007 and Microsoft Office Communications Server 2007 R2 will reach end of support on January 9, 2018. To stay supported, you will need to upgrade. For more information, see Resources to help you upgrade your Office 2007 servers and clients.
In Office Communications Server 2007 R2, the back-end database stores configuration information, contact lists and presence information for users, and any state information required to resume a conference. Presence data and conferencing data are stored in different tables of the same physical database.
In a Standard Edition configuration, all server components are installed on the same computer, including the back-end database. The back-end database on a Standard Edition server uses Microsoft SQL Server 2005 Express Edition with Service Pack 2 (SP2) or later.
In an Enterprise Edition configuration, the back-end database must be configured as a separate dedicated computer. In an Enterprise pool, all servers in the pool share a central Microsoft SQL Server database. This database runs on Microsoft SQL Server 2008 (32-bit or 64-bit) or SQL Server 2005 with Service Pack 2 (SP2) or later (32-bit or 64-bit), and you can cluster it in an active-passive configuration for higher availability.