Default Bandwidth And Downspeeding - Cisco TelePresence Administrator's Manual

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Default bandwidth and downspeeding

About the default call bandwidth
Usually, when a call is initiated the endpoint will include in the request the amount of bandwidth it
wishes to use. For those cases where the endpoint has not specified the bandwidth, you can set
the VCS to apply a default bandwidth value.
About downspeeding
If bandwidth control is in use, there may be situations when there is insufficient bandwidth
available to place a call at the requested rate. By default (and assuming that there is some
bandwidth still available) the VCS will still attempt to connect the call, but at a reduced bandwidth –
this is known as downspeeding.
Downspeeding can be configured so that it is applied in either or both of the following scenarios:
•
when the requested bandwidth for the call exceeds the lowest per-call limit for the subzone or
pipe(s)
•
when placing the call at the requested bandwidth would mean that the total bandwidth limits for
that subzone or pipe(s) would be exceeded.
You can turn off downspeeding, in which case if there is insufficient bandwidth to place the call
at the originally requested rate, the call will not be placed at all. This could be used if, when your
network is nearing capacity, you would rather a call failed to connect at all than be connected at a
lower than requested speed. In this situation endpoint users will get one of the following messages,
depending on the system that initiated the search:
Exceeds Call Capacity
•
Gatekeeper Resources Unavailable
•
Overview and System
Introduction
status configuration
D14049.08
November 2010
Cisco VCS Zones and Clustering and
configuration neighbors peers
Configuring default call bandwidth and downspeeding
To configure the default call bandwidth and downspeeding behavior using the web interface:
•
VCS configuration > Bandwidth > Configuration.
You will be taken to the Bandwidth Configuration page.
To configure these settings using the CLI:
xConfiguration Bandwidth Default
•
xConfiguration Bandwidth Downspeed
•
The options are:
Default call bandwidth (kbps)
Enter the bandwidth value to be used for calls for which no bandwidth value has been specified by
the system that initiated the call.
This value cannot be blank. The default value is 384kbps.
Downspeed per call mode
Determines what will happen if the per-call bandwidth restrictions on a subzone or pipe mean that
there is insufficient bandwidth available to place a call at the requested rate.
On: the call will be downspeeded.
Off: the call will not be placed.
Downspeed total mode
Determines what will happen if the total bandwidth restrictions on a subzone or pipe mean that
there is insufficient bandwidth available to place a call at the requested rate.
On: the call will be downspeeded.
Off: the call will not be placed.
Call Bandwidth
processing control
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