150-359-100-01, Revision 01
Performance Monitoring
HXU-359 List 1
October 27, 2000
35
Table 10.
DS1 Error Definitions
Error Type
Description
ES-L
Errored Seconds-Line—a count of seconds during which one or more of the
following has occurred: BPVs, EXZs, and LOSs. For a B8ZS-coded signal,
BPVs that are part of the zero substitution code are excluded.
SES-L
Severely Errored Seconds-Line—a count of the seconds during which 1544
or more BPVs or EXZs, or one or more LOS defects have occurred. This
number is chosen in accordance with ITU-T guidelines and corresponds to
an approximate BER of 10
-3
. For a B8ZS-coded signal, BPVs that are part of
the zero substitution code are excluded.
LOSS-L
Loss of Signal Seconds-Line—a count of 1-second intervals containing one
or more LOS defects.
CV-L
Code Violation-Line—a count of Bipolar Violations (BPVs) and Excessive
Zeroes (EXZs) occurring over the accumulation period. An EXZ increments
the CV-L by one, regardless of the length of the zero string. For a B8ZS-coded
signal, BPVs that are part of the zero substitution code are excluded from the
count.
