Comtech EF Data CRS-500, Installation And Operational Manual

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CRS-500 1:N Redundancy System
Revision 4
Introduction 1–3 MN-CRS-500
Figure 1-2 shows the system level block diagram of the CRS-500 1:N Redundancy System,
including the optional CRS-500 ISU. A key feature of the CRS-500 architecture is its ability to
allow the Redundant Modem to ‘bridge’ a Traffic Modem. The CRS-500 can be configured to
back up (replace) a Traffic modem when a Unit Fault and/or a Tx/Rx traffic Fault occurs. The
Redundant Modem locks to the Traffic Modem’s receive IF input signal, and the CRS-500
configures the Redundant Modem automatically to match the failed traffic modem’s configuration.
The CRS-500 operation can be customized by selecting a specific Traffic modem as the priority
channel. The operator can also program a delay interval for the Redundant Modem to wait before
backing up a failed Traffic Modem.
Because live traffic is used at all times to verify performance, no external test equipment is
needed to determine the health of the Redundant Modem.
Figure 1-2. Typical CRS-500 Redundancy System – System-Level Block Diagram