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Allocation method, Allocation method -14 – Comtech EF Data SLM-5650A Vipersat User Manual

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Vipersat Configuration

3-14

Vipersat SLM-5650A User Guide

For comparison, the STDMA menu for an SLM-5650A operating as a Remote

unit is shown in figure 3-13. Note that the configuration items for the Remote

screen are a small subset of those for a Hub.

Figure 3-13 STDMA Page (Remote)

Allocation Method

This parameter field is only displayed if the SLM-5650A is being used as a Hub

in the network, and provides the functionality for the STDMA Burst Controller.

Vipersat STDMA has five modes of operation:

• Fixed — all Remotes get the same data slot time (slot size) in the cycle,

regardless of activity. Cycle time is fixed also.

• Dynamic Slot — data slot time of Remotes vary according to activity,

cycle time does not.

• Dynamic Cycle — slot time and cycle time vary according to activity of

Remotes.

• GIR (Guaranteed Information Rate) — each Remote always has at least

the minimum data slot size when needed, and cycle time is variable up to a

maximum of one second.

• Entry Channel — Remotes run in SCPC mode, but STDMA is used for

maintenance and control channel.

The Hub can be configured to operate in one of the five modes by selecting the

Allocation Method from the pull-down menu, as shown in figure 3-14.