Configuration
OCS can be installed in two flavors: Standard and Enterprise. The Standard version is installed on a single Windows Server 2003 with SP1 and uses SQL Server 2005 Express Edition with SP1 for storage and archiving. There is no direct upgrade path from the Standard Edition to the Enterprise Edition. For a smooth transition, administrators deploying the Standard Edition could add a second server for the Enterprise Edition and migrate users gracefully.
For the Enterprise installation, service can be shared among multiple Windows 2003 servers (can be up to 8 servers supporting 125K users) to increase scalability. At the core is the Microsoft OCS Enterprise Pool. This is a collection of servers that handle presence, messaging, and OCS management functions. The pool uses an external Microsoft SQL server for database services. Services for voice conferencing, Instant Messaging conferencing, and Web conferencing can be moved to separate servers for increased scalability. The final core interaction is with the Microsoft Exchange server’s Unified Messaging component for delivery of voice mail to user mailboxes.
For either installation, Standard or Enterprise, part of the OCS installation extends the Active Directory schema to include information such as the SIP user ID. This allows administrators to configure OCS options while creating new users on AD, simplifying the overall management. The recommended hardware platform for either a Standard Edition server or a Front-End Enterprise server (i.e., the servers within an Enterprise pool that handle the client side connections) is a dual processor, dual core 2.6Ghz with mirrored 36 GB HD and 2 GB RAM (4 GB for Enterprise).
CAPACITY PLANNING FOR MICROSOFT OCS 2007
