Alcatel-Lucent 9500 MXC User Manual page 757

SESR Threshold Exceeded
Probable Cause
Recommended Actions
Additional Information
-3
10 BER Threshold Exceeded
3DB 23063 ADAA - Rev 004 July 2007
G.826 severely errored seconds ratio exceeded. This is a warning alarm.
Path conditions, interference or equipment malfunction.
1. Check for other alarms, particularly those that indicate a total LOS due to a
component failure, or a complete path failure:
• Component failure or Rx path failure alarms must be checked before
investigating an SESR Threshold alarm.
• If the only other alarms are Demodulator Not Locked, and its downstream
path failure and path warning alarms, a path failure is indicated, which
may be caused by a complete path fade or a remote Tx failure.
2. If SESR Threshold Exceeded and other G.826 path warning alarms are the
only alarms active, check G.826 and RSL measurements at both ends using
the CT Performance screen:
• If low RSL and G.826 alarms are present at both ends of the link, a path
problem is indicated, which most likely will be caused by a degraded path
due to rain, diffraction or mulipath fading. Check recommended actions
for BER alarms.
• If ESR and SESR alarms are present at just the local end and RSL is
normal, interference from another link should be suspected. Use the CT
History and Event Browser screens to track the onset of ESR alarms,
which for a newly installed interferring link should show a repetition of
G.826 alarm occurences as the new link is installed and commissioned.
An SESR threshold alarm will be preceeded by an ESR threshold alarm, and
BER alarms.
A severely errored second is one-second period, which contains at least 30%
errored blocks or at least one defect. After 10 consecutive SESs a link is
considered to be unavailable.
SESR is the ratio of SES to total seconds in available time during a fixed
measurement interval. For 9500 MXC the measurement interval is 60 seconds,
and the alarm threshold is 10 percent.
Received data has exceeded a threshold of 1 error bit in a data stream of 10
(0.1% error rate). This is a path warning alarm.
9500 MXC User Manual
3
bits
Vol. VI-B-31