DMA OperationsGuide Introduction to the Polycom DMA System
2Polycom, Inc.

The Polycom DMA System’s Primary Functions

Conference Manager

The Polycom DMA system’s Conference Manager uses advanced routing
policies to distribute voice and video calls among multiple media servers
(Multipoint Control Units, or MCUs), creating a single virtual resource pool.
This greatly simplifies video conferencing resource management and uses
MCU resources more efficiently.
The Polycom DMA system integrates with your Microsoft® Active
Directory®, automating the task of provisioning users with virtual meeting
rooms (VMRs) for video conferencing. Combined with its advanced resource
management, this makes reservationless video conferencing on a large scale
feasible and efficient, reducing or eliminating the need for conference
scheduling.
The Polycom DMA system’s ability to handle multiple MCUs as a single
resource pool makes multipoint conferencing services highly scalable. You can
add MCUs on the fly without impacting end users and without requiring re-
provisioning.
The Conference Manager continually monitors the resources used and
available on each MCU and intelligently distributes conferences among them.
If an MCU fails, loses its connection to the system, or is taken out of service,
the Polycom DMA system distributes new conferences to the remaining
MCUs. The consequences for existing calls and conferences depend on
whether they’re H.323 or SIP:
•H.323 calls and conferences on the failed MCU are terminated. But callers
simply need to redial the same number they used for their initial dial-in.
Conference Manager relocates their new conference to the best available
MCU (provided there is still sufficient MCU capacity).
•SIP calls on the failed MCU are automatically moved to another MCU or
MCUs (if available), up to the capacity available.

Call Server

The Polycom DMA system’s Call Server provides the following functionality:
•H.323 gatekeeper
•SIP registrar and proxy server
•XMPP server (client-to-client connectivity, including chat and presence
information, for clients logged into the server)
•H.323 <—> SIP transition gateway
•Dial plan and prefix services
•Device authentication