EXFO IQS-8100 Series Transport Blazer for IQS-600 - Manual (Page 692)

Glossary
678 IQS-8100 Series Transport Blazer
Next-Gen - Link-Capacity Adjustment Scheme (LCAS)
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Step 1: The management system is used to configure the member at
the source and sink NE.
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The source automatically sets the SQ to 255, the highest possible
number at the source and the sink NE. (based on VCAT standard)
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The sink sets the MST to FAIL.
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Step 2: The management system configures LCAS state machine to
ADD.
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In the source, the SQ is automatically set to 4, the next highest SQ
available, and the CTRL is set to ADD.
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The source waits for the sink to send MST = OK for the member
with SQ = 4. While waiting for this MST = OK message, the source
will continue to send a CTRL = ADD for this member.
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Step 3: The source receives MST = OK for member SQ = 4.
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The source sends EOS to the last member added, indicating to the
sink that this is indeed the last member of the VCG, and sends
NORM for the previously defined last member (of course, this is
assuming that no fault occurs on this member during that time).
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The new member begins to carry traffic in the first frame after the
last byte in the frame transporting CTRL = NORM/EOS change.
Note: If multiple members were added, all members would be set to NORM,
except for the last one in the sequence, which would be set to EOS.
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Step 4: The sink detects the transition from ADD to NORM/EOS for the
new member
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The sink sends RS-ACK to the source to acknowledge the new
sequence.
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The sink sets the MST to be consistent with the new sequence.
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Following the proper delay compensation, the source is allowed to
evaluate the new member status when it receives the RS-Ack.