IE-iMcV-T1-Mux/4+Ethernet
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that the cable coming from that device is intact. The appropriate “LNK” (link)
LED is lit to indicate this. However, these signals are not normally transmitted
across a normal store-and-forward Ethernet bridge function. A failed Ethernet
line on one end of the fiber link is not forwarded to the Ethernet port at the
other end of the optical transport. A failed optical line is also not normally
forwarded to the Ethernet port. The FX LinkLoss and LFPT functions are used
to enable these features. Both the LinkLoss and LFPT features are set to
"Disabled" by default.
FX LINKLOSS (FXLL)
FX LinkLoss is a link integrity monitoring feature that forwards fiber link faults
to the RJ-45 Data port to indicate that a fiber link fault has occurred. FX
LinkLoss can be enabled in iView²/CLI.
FIBER FAULT LOOPBACK (FFL)
When a Fiber LOS is detected, the unit sends a Remote Alarm Indication back
to the fiber in the opposite direction. The reception of fault indication on the
fiber line inhibits sending a LINK signal to the Ethernet port. This function can
be enabled at both ends of the fiber line without causing a "lock-up" condition
and will automatically clear when the fault is cleared. FFL can be configured at
both ends of the fiber line with no lock-up condition.
LAST GASP
The iMcV-FiberLinX-II includes a Last Gasp feature, that sends a trap Flinx
Unit Down for the Host unit or a Flinx Remote Unit Down for the Remote unit
(as seen in iView²) when the power to the module fails.
T1 PORTS
ALARM LEVEL
T1 lines are defined as LOST when no signal is received as defined by ITU
G.775 specifications Loss Of Signal (LOS), and are considered in error with a
BER of 10^-6. If either of these conditions lasts for more than 2.5 seconds, an
ALARM state is declared. This error condition must be absent for 10 seconds
for the alarm state to clear.
The starting and ending event of all alarm conditions will generate an SNMP
TRAP when the unit is installed in a managed chassis and set to the in service
state. During initial installation or normal maintenance, the end-user can place
the unit in the Out-Of-Service (OOS) state to inhibit unwanted SNMP TRAP
alarms.