S/UNI-IMA-4 Telecom Standard Product Data Sheet
Released
Figure 22 Link Statistics Flow Diagram
Link Cell Available and
RDAT enabled
TC Mode
Is TC overrun, HEC
Yes
Yes
Is link_state TC
Enabled?
error, or OCD
detected?
Increment dropped_cells
No
No
Is this the second
ICP cell of a stuff
event?
Yes
Increment stuff_events
Increment user_cells
No
Non-ICP Statistics
No
No
Yes
Is this an expected
ICP position?
Is this a valid non-
errored ICP cell?
Is this an IDLE cell?
No
Increment dropped_cells
Yes
Yes
Is this a filler cell
(header, CID, no
HEC, OCD, or CRC
error)?
No
Yes
Is this a valid non-
errored ICP cell?
Increment icp_violations
Increment filler_cells
No
Yes
Increment icp_cells
Are HEC errors or
OCD errors present,
or errored ICP or
filler?
Yes
Increment filtered_cells
ICP Statistics
No
Is link_state IMA Startup
or IMA Monitor, or does
overrun, underrun, LCD,
LIF, IFSM not Sync or
IESM not working exist?
Yes
Increment filtered_cells
No
Increment user_cells
For the group (reader) statistics, four counters are provided for IMA groups, and two for TC
groups. One and only one of these six counters may be incremented for a given cell, as shown
in the flow diagram in Figure 23.
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2020889, Issue 2
69
PMC [ PMC-SIERRA, INC ]
