Nortel Networks 311

300 NT5D33 and NT5D34 Lineside E1 Interface cards

A heavy bit-error rate can cause 200 bit errors to occur much more quickly

than100 seconds. This causes the alarm to be declared sooner.

An alarm condition is not automatically cleared until the system no longer

detects the respective bit error threshold during the corresponding duration

period.

For example, if AL1 threshold of 6 (representing 10-6) is speciﬁed, and a

duration period of 100 seconds is speciﬁed, an alarm is activated if more

than 200 bit errors occur in any 100 second period. As soon as the alarm is

activated, the bit counter is reset to0. If the next 100 seconds pass,and

less than 200 bit errors are detected, then the alarm clears after the alarm’s

duration period. However,if more than 200 bit errors are detected in the next

100 seconds, the alarm condition continues for the designated time period.

The alarm ﬁnally clears when the alarm condition is no longer detected for

the designated period, either by self-clearing (if this function is enabled), or

when the Clear Alarm (C A) command is entered.

In addition to bit errors, the Set Alarm function sets parameters for detecting

frame-slip errors by establishing a threshold necessary to activate an alarm.

If the threshold value is exceeded,a level 2 alarm is activated. Theframe

slip threshold can be speciﬁed from 1 to 255 frame slips per time period.

The duration time period can be speciﬁed from 1 to 24 hours.

When entering the Set Alarm (S A) command, the MMI scrolls through

the previously described series of alarm options. These options are

displayed along with their current value, at which point a new value can be

entered or enter <CR> to retain the current value. Table 126 "Set alarm

options" (page 300) outlines the options available in the Set Alarm (S

A) function.

Table126

Set alarm options

Option Description

AL1 Threshold Sets the allowable bit errors per second before alarm level 1 is

activated. Factory default is 6.

AL1 Duration Sets the duration in seconds (from 1 to 3,600 seconds) that

alarm level 1 is activated. Factory default is 10 seconds.

AL2 Threshold Sets the allowable bit errors per second (from 3 to 9) before

alarm level 2 is activated. Factory default is 10-5.

AL2 Duration Sets the duration in seconds (from 1 to 3,600 seconds) that

alarm level 2 is activated. Factory default is 10 seconds.

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311 01.04 Standard

Release 5.0 23 May 2008