About T.120 Data Collaboration Support; Configuring Encoding/Decoding Protocols - Cisco 3521 Administrator's Manual

Configuring Gateway Settings

About T.120 Data Collaboration Support

The gateway provides full end-to-end support for T.120 data collaboration sessions, provided all
terminals support the T.120 standard in their conferencing applications. In video calls with data transfer,
the gateway accepts whatever bandwidth the ISDN connection defines for the data and dynamically
adjusts the outgoing bandwidth used for data by using the MLP, HMLP and VarMLP formats.
If transcoding or T.120 capabilities are required, the gateway has to reserve resources for these. The
gateway can differentiate between those calls that support T.120 and those that do not. When receiving
calls, the gateway can check whether you are reserving resources for transcoding or for T.120
capabilities.
The gateway enables the user to determine the trade-off between the number of non-T.120 calls that the
gateway can support and the number of calls sent with T.120 capabilities. The total number of calls that
the gateway can support is accordingly reduced by this reallocation of resources.
The H.320 standard defines space allocation within a call. The H.320 standard defines the logic for bit
rate allocation among audio, video, and data channels in the context of the overall bit rate of a call. If
you work with T.120, reallocation of bandwidth is always at the expense of available video resources.
The requirements of the H.320 standard govern this reallocation—it is not configured in the gateway.
The gateway simply decides whether or not to send T.120 capabilities. You configure T.120 capabilities
in the Advanced section of the Gateway interface Settings tab.

Configuring Encoding/Decoding Protocols

In the Media Modes section of the Settings tab, you can configure and prioritize encoding and decoding
protocols.
Procedure
In the Gateway interface, on the sidebar, click Gateway (if not already selected).
Step 1
Click the Settings tab.
Step 2
Click the Media Modes button.
Step 3
In the Transcoding priority field, choose the priority that determines the order of requested audio
Step 4
transcoding or choose Disable to disable audio transcoding priority.
Note
You can configure the following audio codec settings:
Step 5
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You can configure the following video codec settings:
Step 6
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You can configure the following data settings:
Step 7
Administrator's Guide for Cisco IPVC 3521 BRI Gateway, Cisco IPVC 3526 PRI Gateway, and Cisco IPVC 3540 PRI Gateway
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When your unit includes both a gateway and a Cisco IPVC 35xx MCU, G.728 transcoding is
supported on the Cisco IPVC 35xx MCU only.
Select the Enable G.722 check box to enable transparent support for the G.722 audio codec.
Select the Enable G.722.1 check box to enable transparent support for the G.722.1 audio codec.
Select the Enable G.728 check box to enable transparent support for the G.728 audio codec.
Select the Enable H.263 check box to enable transparent support for the H.263 video codec.
Select the Enable H.263+ check box to enable transparent support for the H.263+ video codec.
Select the Enable H.264 check box to enable transparent support for the H.264 video codec.
Chapter 3 Configuring the Cisco IPVC 3500 Series Gateway
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