Comtech EF Data Vipersat CDM-570L, User Manual

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Vipersat Configuration
3-22
Vipersat CDM-570/570L User Guide
Figure 3-31
STDMA Statistics screen (Remote)
The window of time that is used to average the accumulation of statistics can
be set by entering W at the command prompt in the Hub screen, then entering
the number of seconds (from 1 to 20).
To
clear (reset to 0) these statistics, enter C at the command prompt.
Show Hub Statistics
Entering a W at the command prompt in the STDMA screen (figure 3-6)
displays the current statistics for the target CDM-570/570L Hub, as shown in
figure 3-32.
Figure 3-32
Hub Statistics screen
The Burst Controller monitors statistics in the received ACK from each Remote.
The statistics report the fill status of the STDMA buffers. The Burst Controller
builds a table of the group and calculates the relative buffer fill for each Remote.
It then calculates the length of the Data Slot for each Remote based on the Mini-
mum Slot Size plus a percentage of the Available Bandwidth. Idle remotes
would receive a Data Slot equal to the Minimum Slot Size.
In the figure 3-32, Remote 1 with IP address 10.1.128.1 had activity during the
averaging period. It captured 37.8% of the total slot time and had an average
slot length of 283 ms. Remotes 2, 3, and 4 had 41.5%, 18.1%, and 7.6% respec-
tively. The dynamic range of STDMA is a function of the difference between