Alcatel-Lucent 9500 MXC, User Manual, Page: 757 / 916

9500 MXC User Manual
3DB 23063 ADAA - Rev 004 July 2007 Vol. VI-B-31
SESR Threshold Exceeded
G.826 severely errored seconds ratio exceeded. This is a warning alarm.
Probable Cause
Path conditions, interference or equipment malfunction.
Recommended Actions
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.
Additional Information
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.
10
-3
BER Threshold Exceeded
Received data has exceeded a threshold of 1 error bit in a data stream of 10
3
bits
(0.1% error rate). This is a path warning alarm.