NCast N-Way Server - Manual (Page 6)

NCast N-Way Reference Manual
1.5.2.Archive Playback using RTSP
Several models of the Telepresenter allow recording of webcasts or conferences. These files are created as
MPEG media files and stored locally until the file is downloaded and removed from the unit.
A Telepresenter is not designed to be a Video-on-Demand playback server. Continuous playback of captured
files would interfere with the real-time capture and encoding activities of the unit. Nor is there any provision for
backed-up storage of the files. These functions are best done elsewhere in the network.
An N-Way Server is capable of storing archived files and playing them back on demand from its hard-drive. Files
may be uploaded to the server using the automatic FTP upload facilities within the Telepresenter.
There is a configuration page within the Telepresenter to define the FTP server, account and password. The
archived .mp4 file, along with its associated .xml file, can be uploaded immediately after a Session stops, or the
upload can be programmed for later in the day or after business hours when the network will be less busy.
Once the file is residing in the content directory on the server, a simple RTSP link is all that’s needed to play back
the file on demand.
1.5.3.Multicast Bridging
Through the use of N-Way bridging and tunneling protocols, multiple Telepresenters, which are not situated on a
native multicast network, can participate in a conference through the use of the server as a bridge. All the
standard Telepresenter modes of operation (one-way streaming, full-duplex streaming and collaboration mode)
are supported through use of the bridge. The N-Way Server must be located at a network point where multiple
streams (one for each participating unit) can exist and flow without impacting or overloading the network.
Multicast traffic at each end point is forwarded through the tunnel and emerges at the bridge where it is routed to
all participating parties. The simplest conceptual model for this usage is a hub-and-spoke arrangement, where
each remote Telepresenter is at the end of a spoke, and the N-Way Server is the hub located in a high-bandwidth
network operations center.
More complex architectures are possible for special applications (See Chapter 6). If the N-Way Server itself is
located on a multicast network, traffic can flow from the multicast network through the bridge and its tunnels to the
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