Comtech EF Data VMS v3.12.x Vipersat - Manual (Page 492)

Carrier Presence Switching MN/22156, rev 12
E-36 VMS User Guide
Carrier Presence Switching
Overview
Carrier Presence Switching (CPS) allows the VMS to autonomously manipulate
carriers through presence-based distributions within the satellite bandwidth
pools. This switching type is determined by the presence or absence of carriers,
executing bandwidth shifts governed by divisional carrier distribution and indi-
vidual policy settings. CPS is a Hertz defined switching method in which a
carrier may occupy a large segment of bandwidth even with little to no traffic
load on the terminal.
Typically, the VMS does not resize or move carriers unless requested to do so.
However, a Carrier Presence switch, when enabled, will change the position and
allocation of active carriers due to the addition or removal of carriers. But in this
scenario, the Remote is not initiating the switch with a request for additional
bandwidth. The resizing and movement of carriers is equally distributed based
on available bandwidth and utilizing site policies, while always observing guar-
antees.
Switching Parameters / Configuration
The Carrier Presence Switching feature is not simply enabled or disabled in the
VMS; it requires a specific combination of parameter settings within the
group(s) of Remotes to become operational. The following switching parame-
ters must be configured as specified in order for CPS to become fully functional.
Note: It is NOT recommended to enable automatic switching functions—Load
and/or Application—for a group of Remotes that will be utilizing CPS;
undesirable behavior will result.
Entry Rate — InBand Application Policies
Previous to version 12 of the VMS, site minimum and maximum rate settings
were provided, with the minimum setting specifying the dSCPC entry rate from
the shared access channel. The Entry Rate setting (figure E-24) now provides
for more flexibility when entering into the bandwidth pool, where the first
switch may be greater than the site minimum. This setting can be any value
between the Switch Rate Min/Max Limits (figure E-25), which the system will
attempt to honor, depending on available resources. Note that this is not neces-
sarily a guaranteed rate.
NOTE