Reference
ST2400A SDH Test Set User Manual
3-41
Error Measurement Details
•
Error Reporting
- In both SONET and SDH mode, the ST2400A will provide Total Errors,
Errored Seconds (ES), bit error rate (BER) and Severely Errored Seconds (SES). for B1, B2,
B3, FEBE-L (MS-REI), FEBE-P (HP-REI) and Payload Bit (TSE) errors. In SDH mode, the
ST2400A will provide Errored Blocks (EB) and Background Block Errors (BBE) for G.826
error analysis measurement. In SDH mode, the ST2400A will properly detect and count
Consecutively Severely Errored Seconds (CSES) per G.826. In SONET mode, Severely
Errored Seconds (SES) will be counted based on SES criteria in GR-253-CORE.
Consecutively Severely Errored Seconds will be measured for B1, B2, B3 and MS-REI
errors, and displayed in SDH mode only.
•
In SDH mode, all overhead, alarms, failures, and errors are displayed or printed in ITU-T
terminology (for example, FEBE is REI, FERF is RDI, etc.).
•
The RS-B1, MS-B2, HP-B3, MS-REI, HP-REI and TSE summary menus include: the EB
(Errored Blocks) which is the error count; the BBE (Background Block Errors); the ES
(Errored Seconds); and the SES (Severely Errored Seconds). These measurements conform
to the ITU G.826 standard.
•
The submenu BBER (Background Block Error Ratio); ESR (Errored Seconds Ratio); and
SESR (Severely Errored Seconds Ratio) conforms to the ITU G.826 standard.
•
The submenu AEB, ABBE, AES, and ASES, are the Errored Blocks; Background Block
Errors; Errored Seconds; and Severely Errored Seconds counted during Available time—
conforming to the ITU M.2101 standard.
•
The menu UAS (Unavailable Seconds) count and UASR (Unavailable Seconds Ratio)
conform to the ITU G.827 standard.
G.826 and M.2101 Measurements in SDH Mode
In SDH mode, the following measurements are calculated for each of the B1, B2, and MS-REI
error types:
TOT (Total Errors)
Total number of errors detected since testing was started (or restarted).
BER (Bit Error Ratio)
Ratio of number of errors detected to the number of bits monitored for
errors since testing was started (or restarted). (Computed only for B1, B2 errors; Not computed
for MS-REI errors.). HP-REI ES can occur with HP-RDI.
ES (Errored Seconds)
Number of seconds since testing was started (or restarted) in which one
or more errors were detected. B3 ES can occur with LOP or Path AIS.
SES (Severely Errored Seconds)
Number of seconds since testing was started (or restarted)
in which the number of detected errors exceeded the severely errored second threshold or in
which a relevant defect was detected. Relevant defects are: LOS (all SES), LOF (all SES), MS-
AIS (B2 and MS-REI SES only), and MS-RDI (MS-REI SES only). SES threshold is currently
set to 30% of the blocks (SDH frames) per second for B1, B2, and MS-REI errors. (Thresholds
Summary of Contents for ST2400A
Page 7: ...ST2400A SDH Test Set User Manual vii Index I 1...
Page 12: ...General Safety Summary xii ST2400A SDH Test Set User Manual...
Page 13: ...Getting Started...
Page 14: ......
Page 24: ...Operating Basics...
Page 25: ......
Page 44: ...Reference...
Page 45: ......
Page 94: ...Reference ST2400A SDH Test Set User Manual 3 49...
Page 95: ...Appendices...
Page 96: ......
Page 113: ...Specifications SDH ST2400A SDH Test Set User Manual A 17...
Page 134: ...Factory Defaults C 4 ST2400A SDH Test Set User Manual...