Lucent DDM-2000 OC-3 User And Service Manual page 666

363-206-285
Issue 2, February 2000
Table B – RTRV-ALM Message Descriptions (Continued)
Description
inc. STS1 sig failed (BER)
inc. STS1 unequipped
inc. STS1 yellow
inc. VT AIS
inc. VT LOP
Alarm
Level
CR or MN For ring applications, the bit error ratio (BER) of the
MN
NE ACTY
CR, MJ,
MN, or
None
MJ or MN
DDM-2000 OC-3 M
Trouble Clearing:
Meaning
specified STS-1 signal exceeds the signal fail
–6
threshold (10 ). For VT1.5 path-switched rings,
the system responds by inserting VT path AIS in
each pass-through VT contained in the STS-1.
Locally, the system will select the VTs from the
STS-1 on the other ring, as appropriate.
Likely causes: Failure of the near end OLIU circuit
pack reporting the STS-1 failure, failure of the far
end OLIU circuit pack, or failure of the receive fiber
if the OC-3/OC-12 is also reporting a failure.
The system has detected the unequipped code
(SONET path overhead signal code label byte=0)
on an in-service STS-1 channel.
Likely causes: An upstream STS-1 cross-connect
has been deleted.
The system has detected an incoming STS-1
yellow signal, which indicates that the far end is
receiving STS-1 AIS on the active OC-3 line. The
system responds to the STS-1 yellow signal by
transmitting DS1 or DS3 yellow toward the DSX.
Likely causes: Incomplete or incorrect
cross-connect provisioning in end-to-end network,
unprotected unidirectional failure of the OLIU
circuit pack, or fiber at some point in the end-to-end
path.
The system has detected VT path alarm indication
signal (AIS) incoming from the active OC-3 line.
The system responds by transmitting DS1 AIS
toward the DSX-1 and VT yellow toward the fiber
from which the AIS is being received.
Likely causes: Incomplete or incorrect
cross-connect provisioning in end-to-end network
(In ring applications, this alarm may be caused by
fiber or OLIU circuit pack failures). Unprotected
removal or failure of a DS1 circuit pack at the far
end.
The system has detected a VT loss-of-pointer
(LOP) condition.
Likely causes: Unprotected failure of a DS1 circuit
pack at the near end, unprotected failure of a DS1
circuit pack at the far end, unprotected failure of a
MXRVO circuit pack at the near end, or
unprotected failure of a MXRVO circuit pack at the
far end.
ULTIPLEXER
TAP-107
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