Alcatel-Lucent 1643 AMS Applications And Planning Manual page 260

SHDSL Overview
Parameter
OFS/AIS
CRC6
TMP
The default thresholds of the parameters are fix preset and cannot be changed. For
more details, please refer to the User Operations Guide, Chapter Performance
monitoring concepts - Available PM data.
Definitions of PM Parameters for SHDSL
For SHDSL, a performance monitoring block coincides with an SHDSL frame. Since
the SHDSL frame length is 6 ms, there are 1662/3 blocks per second. The following
definitions are applicable for PM parameters that are used for SHDSL segment
termination points:
• UAS:
Each second that is part of unavailable time is counted as a UAS. Unavailable time
starts after 10 consecutive SESs. These 10 seconds are part of unavailable time.
Unavailable time stops after 10 consecutive non-SESs. These 10 seconds are not
part of unavailable time.
• SES:
Each second in which 50 or more CRC-6 words are in error or in which a LOSW
defect is active is counted as a Severely Errored Second, provided the second is not
a UAS. An SES detection threshold of 30% is equivalent to 50 errored blocks.
• ES:
Each second in which one or more CRC-6 word is errored or in which a LOSW
defect is active is counted as an Errored Second, provided the second is not a UAS.
• BBE (CV):
Each SHDSL frame with an errored CRC-6 word is counted as a Background
Block Error (Code Violation), provided the second in which the error occurs is not
an SES or a UAS. Hence, the maximum possible number of BBEs per second is
49.
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12-14
Name
OOF or AIS Second
CRC6 anomaly
Total Measurement Period
Alcatel-Lucent - Proprietary
See notice on first page
Definition
Second containing ab LOSW or AIS
event
Number of CRC6 block errors (same
as BBE, but not inhibited by SES or
UAS)
Elapsed time in current interval
SHDSL features
365-312-801R7.2
Issue 3, May 2007