Teledyne QMultiFlex-400 Installation And Operating Handbook page 162

QMultiFlex-400™ Installation and Operating Handbook
IP Traffic
and control
Main Site Loses Connection
Customer
Network
Main Site Loses Connection
IP Traffic
and control
Figure 8-26 – Two Geographically Located 1:1 Pairs – All Failure Modes
Failure Mode 1
If the Main site suffers a failure in the Tx path RF equipment, the monitor demodulator will
become unlocked and it will result in a switchover to the peer site after 8 seconds. The Main
site Modem will still be receiving Status messages from the Standby site Modem. The
monitor Demodulator will report loss of lock indicating that the Tx path has failed. This will
cause the Main site Modem to switch off its carrier and change its status to Standby in the
status messages. The Standby site receiving these messages will ignore the monitor
Demodulator status (unlocked) and will then initiate a switch over and report that it is now
the Main site Modem.
Failure Mode 1:
Monitoring:
Failure Mode 1:
No Hub Transmit
Failure Mode 3:
Total Site Failure
Failure Mode 4:
to Monitor Address
Monitor
IP Address
Failure Mode 5:
with Standby Site
Tx RF Path Failure
Monitor demod locked
On-Line HUB 1:1 Pair
On-Line 1:1 Pair Fails Switchover
Standby HUB 1:1 Pair
8-31
Failure Mode 2:
Poor Rx C/N
Failure Mode 6:
Standby
Main
Site
Site