SCP-PLL735-010-03H
4
January 6, 2003
PLL-735 Lists 1, 2 and 3
M
ONITORING
, H
ISTORY
AND
D
IAGNOSTICS
DICOLUs provide extensive real-time, nondisruptive monitoring of HDSL transmission performance parameters
for all units in a circuit. You can select threshold settings for the performance monitoring measurements at the
appropriate DICOLU screen. These settings cause alarms to be activated at the designated threshold setting.
HDSL performance is also monitored. Monitored parameters include the following:
•
HDSL - Noise margin, insertion loss, ES, UAS
•
ISDN Interface - ES and UAS seconds
Performance Parameters
Based on the monitored parameters, the DICOLUs derive the following performance parameters:
•
MAR: A measure of the ratio of signal power to noise power, in decibels (dB), at a receiver point. A value of
0 dB means that the predicted transmission BER is equal to 10
-7
, a value of 6 dB means the predicted
transmission BER is equal to 10
-10
. The Status screen of the console continuously updates the margin value.
You can set the high and low values of this parameter for the DICOLU and the RT at the
HDSL-B Status Screens” on page 22
and the severity of the alarm at the
“HDSL-A and HDSL-B Alarm Types
. View the results of these settings at the
“Overall Status Screen” described on page 21
.
•
LOSW: The DICOLU has detected an error in one or more bits in five consecutive HDSL SYNC words. Five
consecutive SYNC words must be received without error to clear this condition. A LOSW condition generally
indicates the loop is down, thus data cannot be transmitted. The DICOLU uses this parameter to derive UAS
performance parameter. You can set the severity of the alarm at the
“HDSL-A and HDSL-B Alarm Types
. View the results of these settings at the
“HDSL-A and HDSL-B Summary Screens” on
.
•
HDSL ES: An interval of 1 second during which at least one CRC is detected at the incoming HDSL port.
You can set the value of this parameter for the DICOLU and the RT at the
Thresholds Screens” on page 38
and at the
“HDSL-A and HDSL-B Alarm Types Screens” on page 39
set the
severity of the alarm. View the results of these settings at the
“HDSL-A and HDSL-B Summary Screens” on
.
•
HDSL UAS: An interval of 1 second during which a loop is down. You can set the value of this parameter
for the DICOLU and the RT at the
“ISDN-A and ISDN-B Alarm Thresholds Screens” on page 43
and at the
“HDSL-A and HDSL-B Alarm Thresholds Screens” on page 38
set the severity of the alarm. View the results
of these settings at the
“HDSL-A and HDSL-B Summary Screens” on page 25
Alarms
The DICOLUs generate the listed alarms for fault conditions on the HDSL transmission facility and at the
application interface. You can view the alarm status from the
“Overall Status Screen” described on page 21
.
•
MAR - The margin default value or a value you selected has been reached, or the unit is below the current
threshold value set.
•
ES - The errored seconds are measured by both 15-minute or 24-hour thresholds. The threshold has been
reached or exceeded if an alarm exists.
•
UAS - The unavailable seconds are measured by both 15-minute or 24-hour thresholds. The threshold has
been reached or exceeded if an alarm exists.
•
PFO - The DICOLU cannot power the RTs due to an open circuit.
•
PFS - The DICOLU cannot power the RTs due to a short circuit.
•
PGF - The DICOLU cannot power the RTs due to HDSL Tip or Ring fault to ground.