Comtech EF Data Vipersat CDM-570L, User Manual

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Vipersat Configuration
3-32
Vipersat CDM-570/570L User Guide
The SCPC Step Down Threshold establishes the percentage of bandwidth use
that will trigger a switch down from the present SCPC rate to a lower rate to
ensure efficient bandwidth usage.
Typically the default value will be optimum, but if a different threshold is
desired, an alternate value can be specified by entering D at the command
prompt in figure 3-34. Note that this value must be less than the value specified
for the SCPC Step Up Threshold.
SCPC Step Delay
This menu item appears for the Remote modem only.
The
SCPC Step Delay feature provides a switching delay period to ensure that
a premature switch up or down in the SCPC rate does not occur due to a tempo-
rary rise or fall in traffic.
A default value (in seconds) is provided, but this parameter can be modified by
entering W at the command prompt in figure 3-34.
SCPC Step Up Excess
This menu item appears for the Remote modem only.
During each SCPC Step Up switch, the excess capacity data rate value entered
by this command is added to the new SCPC data rate. This excess is added each
time an SCPC Step Up switch occurs. This setting makes additional bandwidth
available for when the demand arises while minimizing step up switching
events.
A default percentage value is provided, but this parameter can be modified by
entering E at the command prompt in figure 3-34.
ToS Switching Parameters
This menu item appears for the Remote modem only.
When ToS switching is enabled on a CDM-570/570L, the parameters for ToS
switching must be defined by entering P from the STDMA/SCPC Auto Switch-
ing screen (see figure 3-34). The TOS Switching Control menu shown in
figure 3-41 is displayed, allowing parameter entry for the desired ToS service to
be applied.