Alcatel 1660SM Technical Handbook page 438

– Failure Condition: the Failure Condition FC
N.B. SSF =Server Signal Fail, from upstream.
– REI alarm detection (E): the REI
– RAI alarm detection (A): the RAI
– Sa6: the Sa6 bit is read for every 4 consecutive frames, to check the presence of the loopback2
command, when 4XSa6=1010, for 8 consecutive times.
– Data Error detection (CRC–4): errors integrity check on the incoming data, according to CRC–4
procedure (Cyclic Redundancy Check), as defined in G.706. In case of errors, the alarm ERR
arised.
– A* insertion: the A bit is
•
passed transparently in standard applications
•
set to '1' (*) when a failure condition (FC
•
set to '1' (*) when forced from the controller;
N.B. (*): this option is enabled only in case of Leased Line applications.
– E bit insertion (E): the outgoing E bit is set to 0 when
•
a failure condition (FC
•
errors (ERR
2M
•
the E insertion may be inhibited from controller, in this case E=1.
•
E=1 in other cases.
•
set to '0' (*) when Power Fail alarm (PWF) is active;
N.B. (*): this option is enabled only in case of Leased Line applications.
– Sa4* insertion: the bits Sa4 to Sa8 are passed transparently in standard applications,
•
Sa4 is set to '0' (*) when Power Fail alarm (PWF) is active, passed transparently otherwise.
N.B. (*): this option is enabled only in case of Leased Line applications.
– CRC–4 bits insertion: the CRC–4 on data is performed and the result is inserted on bits C1 to C4,
according to G.706.
– Frame Word insertion (FW): the basic–frame and multi–frame alignment words are inserted on the
frame.
– AIS insertion: a continuous bitstream of all 'ONES' is inserted, in case of occurrence of
•
force command from the controller;
•
a failure condition (FC
•
(*) a failure condition (FC
N.B. (*): this option is enabled only in case of Leased Line applications.
ALARMS, STATUS AND COMMANDS CONVEYED FROM/TO CONTROLLER
Every alarm, status and errors counting results are reported to the controller, for monitoring purposes:
– LOS, REI, RAI, FC, ERR(CRC–4), SSF detected either in upstream and in downstream signal
directions
N.B. LOS = Loss of user Signal; SSF= upstream Server Signal Fail.
The controller sends the following commands, in order to enable the relevant functions:
– LB–2, LB–RX, BF, MF, ForceA, InhibitE, etc.
N.B. BF= Basic Frame; MF = Multi Frame.
ED
02
alarm is the "OR" of SSF
U
alarm is detected if E=0.
U
alarm is detected if active for 5 consecutive frames.
U
) is detected on signal from user (SY2Min);
2M
) are detected on data from user (SY2Min);
) on signal from SDH network (UP2Min);
U
) on signal from user (SY2Min).
2M
LOF
,
) is detected on signal from user (SY2Min);
2M
3AL 91669 AA AA
674
, AIS , AUXP alarms.
U U U
is
U
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