About Downspeeding; About Subzones; Default Links Between Subzones; About The Traversal Subzone - Cisco TelePresence Video Communication Server Administrator's Manual

Field Description
Downspeed Determines what happens if the total bandwidth
total mode 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.

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 pipes
n
when placing the call at the requested bandwidth would mean that the total bandwidth limits for that
n
subzone or pipes 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"
n
"Gatekeeper Resources Unavailable"
n

About subzones

The Local Zone is made up of subzones. Subzones are used to control the bandwidth used by various
parts of your network, and to control registrations.
When an endpoint registers with the VCS it is allocated to an appropriate subzone, determined by
subzone membership rules
You can create and configure subzones through the
Zone > Subzones).
Three special subzones — the Default Subzone, the Traversal Subzone and the Cluster Subzone
(only applies if the VCS is in a cluster) — are automatically created and cannot be deleted.

Default links between subzones

The VCS is shipped with the Default Subzone and Traversal Subzone (and Default Zone) already
created, and with links between the three. You can delete or amend these
model restrictions of your network.

About the Traversal Subzone

The Traversal Subzone is a conceptual subzone. No endpoints can be registered to the Traversal
Subzone; its sole purpose is to control the bandwidth used by
Cisco VCS Administrator Guide (X6.1)
based on endpoint IP address ranges or alias pattern matches.
Subzones
Bandwidth control
Usage tips
page (VCS configuration > Local
default links if you need to
traversal calls.
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