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EXFO IQS-8100 Series Transport Blazer for IQS-600 User Manual

Page 694

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Glossary

680

IQS-8100 Series Transport Blazer

Next-Gen - Link-Capacity Adjustment Scheme (LCAS)

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Temporary Removal

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Step 1: A fault is detected at the sink for a member (i.e., STS-1 [3,2],
AU-3 [3,2]).

At the sink, the fault can take the form of a member status
unavailable (MSU) or transport signal degraded (TSD). An MSU
would be generated by an AIS or LOP for example. The TSD would
be errors detected on the path crossing a certain threshold.

If the source of these members was sending a NORM or EOS in this
condition, the sink would start sending a MST = FAIL for the
specific SQ.

Typically, a hold-off timer can be configured to delay the reporting
of MST = FAIL to avoid transient error occurrences.

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Step 2: Member removal

At the sink NE and upon the detection of the MSU, the member
would be removed immediately. However, if the failure is related
to a TSD, the member would be removed only when the sink NE
receives the DNU from the source NE.

At the originating source NE a detection of the MST = FAIL will
trigger the replacement of the NORM/EOS by a DNU condition.
Within the remaining active member, the member with the highest
SQ will send EOS in the CTRL field.