Comtech EF Data Vipersat CDM-570L, User Manual

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Chapter
3 -
Using the Command Line Interface (CLI)
3-9
Vipersat Configuration
STDMA Tx Rate
This menu item shows the STDMA transmit rate in bps. This item is read-only
and cannot be modified in this menu.
Hub Type
This menu item is only displayed if the CDM-570/570L is being used as a Hub
in the network. Vipersat STDMA has five modes of operation:
• Fixed - All remotes get the same size slot, regardless of each remote’s
activity
•
Dynamic Slot - Slot size is adjusted each cycle depending on activity
during the previous cycle
•
Dynamic Cycle - A dynamic cycle allows changing the cycle time, and
corresponding latency, as loads change always providing minimum
latency for the current traffic load.
• GIR - Guaranteed Information Rate allows assigning a guaranteed data
rate to a channel.
• Entry Channel - Entry channel mode provides an on-demand channel for
applications such as a mobile remote.
Figure 3-8
Hub Type prompt
Entering a number from 1 to 5 at the command prompt determines the band-
width allocation mode for the Hub CDM-570/570L.
Note: If the selected Hub STDMA mode is GIR (Guaranteed Information
Rate) or Entry Channel , normal load switching is automatically
disabled. In GIR mode, the Remote is switched to SCPC as soon
as the GIR threshold is reached, if there is a switch rate defined.
In Entry Channel mode, the Remote is switched to SCPC as soon
as the Hub receives the first transmission from the Remote.
Refer to Appendix B, "Automatic Switching" for details on how each of the
bandwidth allocation modes functions and the parameters and processes used to
calculate the commands for each mode.
NOTE