Chapter 1 - General 1-7
Product Description
1.5.3 Release
New Redundancy Features
Redundancy Heartbeat Message for Primary Hub Units
Provides the option for a periodic communications check message to be sent
from the Hub modem to the VMS for backup recovery in N:M redundancy
(protected) configurations. This feature allows the message interval to be speci-
fied by the administrator, and can be enabled through either the CLI or the
VMS.
New QoS Features
Dynamic Buffering
Reduction of overall system latency is now optimized in the Vipersat network
by dynamic buffering enhancements that provide a minimum buffer size of 2
MB, with a user-specified latency period (five second maximum).
QoS Rule Switching
With QoS Rule Switching, an STDMA to SCPC switch can be initiated based
upon any type of IP traffic flow that matches a defined QoS queue.
Burst Fast Acquisition Timing (BFAT)
The BFAT feature provides dramatic reduction in data acquisition times for
Vipersat modems operating in STDMA (burst) mode at low data rates (64 kbps
to 256 kbps). Preamble size is automatically recalculated and adjusted by the
modem for optimum performance. This feature can be enabled in modems oper-
ating at 3/4 QPSK.
STDMA Slot Quantization
Utilizing Turbo FEC Block mode, Vipersat STDMA Slot Quantization automat-
ically sizes the data slot to hold an integral number of FEC blocks, based on the
current data rate. This results in increased STDMA efficiency.
RTP Inactivity Timeout
The timeout period for Real-time Transfer Protocol (e.g., voice, video) data
flows is now set for 10 seconds of inactivity to reduce the wait period until the
next switch state occurs, thus increasing SCPC bandwidth utilization.
Parameter File Consolidation
Configuration parameters for the entire CDM-570/570L modem (base modem
plus IP router module) are now stored in one common parameter file. All