238 APPENDIX B: PATHBUILDER S330/S310 MODULE AND APPLICATION OVERVIEW
Figure 177 depicts the effects of structured versus unstructured service on the DS1
framing.
Figure 177 Structured Versus Unstructured Effects on Transit DS1
Video Conferencing 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 (deļ¬ned 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.
DS1
ESF
FDL
AAL 1 DS0 DS0 DS0 DS0 A&B
DS1 Structured N x 64 Kbps
Bit
Bucket
PathBuilder S330/S310 Interface
DS1
ESF
FDL
AAL 1 DS1
DS1 Unstructured
DTE
T
iming
DS1 = 1,544 Mbps
DS0 = 64 Kbps
DS - Digital Signal
ESF - Extended Superframe
PathBuilder S330/S310 Interface
