The topics in this section summarize the most important new or changed conferencing features in Microsoft Unified Communications Managed API (UCMA) 3.0. These features can be divided into three broad areas.
Joining the conference and the in-conference experience
To learn how UCMA 3.0 Conferencing API works, it is essential to first understand the underlying infrastructure. All conferences are scheduled by the use of a Microsoft Lync Server 2010 Front End Focus Factory and stored in the User Services database. The Focus stands for the central point of conferencing command and control. It runs on every instance of a Lync Server 2010 Front End. The Multipoint Conferencing Units (MCUs) for chat, application, and desktop sharing, or data collaboration usually run on the Front End, although the Audio Video MCU runs on a separate server role of the Lync Server 2010 architecture. The MCU Factory is responsible for allocating MCUs to an activated Conference and monitoring their health. The following illustration shows a typical conferencing topology.
The following illustration shows a logical view of Lync Server 2010, together with the protocols that are used.