Video Conferencing; Point-To-Point Video Conferencing - 3Com SuperStack II PathBuilder S330 Reference Manual

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PPENDIX ATH UILDER

Video Conferencing

S330/S310 M A
ODULE AND PPLICATION
Figure 177 depicts the effects of structured versus unstructured service on the DS1
framing.
Figure 177 Structured Versus Unstructured Effects on Transit DS1
PathBuilder S330/S310 Interface
DS1
AAL 1
ESF
FDL
Bit
Bucket
DS1 = 1,544 Mbps
DS0 = 64 Kbps
DS - Digital Signal
ESF - Extended Superframe
The serial port of the PathBuilder S330/S310 CBR module has two types of
interface: V.35 for video data and RS-366 for video dial. These interfaces are
broken out from a 50-pin connector on the S330/S310 via a Y cable.
The V.35/RS-366 serial CBR connector is ideal for directly connecting to H.320
video codec devices such as PictureTel, Vtel, and CLI. These device applications are
used for group-room conferencing applications and distance learning, typically
over an ISDN dial network. The PathBuilder S330/S310 platforms simulate a dial
ISDN network over an ATM network, allowing you to integrate voice, video, and
data on a single ATM network.
The RS-366-based video dial feature allows a dial-based video session using the
ATM circuit emulation provided by the PathBuilder S330/S310 platforms. The
PathBuilder S330/S310 supports two modes of video conferencing: point-to-point
and multi-point.

Point-to-Point Video Conferencing

In point-to-point video conferencing two or more PathBuilder S330/S310 CBR
modules are connected via their serial (V.35/RS-366) ports. To set up point-to-point
conferencing, you build virtual circuits (defined by transmit and receive vpi/vci
combinations) to connect the remote units. To activate a point-to-point
conference, both ends must dial their respective destination phone numbers over
the RS-366 interface. Video data is then transmitted and received over the V.35
interface. No bandwidth is allocated until the connection is made.
O
VERVIEW
DS0 DS0 DS0
DS1 Structured N x 64 Kbps
PathBuilder S330/S310 Interface
DS1
AAL 1
ESF
FDL
DTE
T iming
DS0 A&B
DS1
DS1 Unstructured