Nortel Networks Circuit Card 311 - Manual (Page 248)

248 NT5D11 and NT5D14 Lineside T1 Interface cards
Port 20 off hook, Port 21 on hook, Port 22 on hook, Port 23
on hook
Performance counters and reporting
The MMI monitors the performance of the T1 link according to several
performance criteria including errored, bursty, unavailable, loss of frame
and frame slip seconds. It registers the performance of these criteria by
reading their status every second and counting their results. These counts
are accumulated for an hour, and then they are reset to 0. Previous hour
count results are maintained for each hour for the previous 24 hours.
Performance counts are maintained for the following:
• Errored seconds – one or more CRC-6 errors, or one or more out of
frame errors in a second.
• Bursty seconds – more than one and less than 320 CRC-6 errors in a
second.
• Unavailable seconds – unavailable state starts with 10 consecutive
severely errored seconds and ends with 10 consecutive severely errored
seconds (excluding the final 10 non-severely errored seconds). Severely
errored seconds are defined as more than 320 CRC-6 errors, or one or
more out of frames in a second.
• Loss of frame seconds – loss of frame or loss of signal for three
consecutive seconds.
• Framer slip seconds – one ore more frame slips in a second.
The MMI also maintains an overall error counter that is a sum of all the
errors counted for the five performance criteria listed above. The error
counter can only be cleared by entering the "Clear Error" command. It
stops counting at 65,000. The error counter provides an easy method to
determine if an alarm condition has been corrected. Simply clear the error
counter, wait a few minutes, and display performance to see if any errors
occurred since the counter was cleared.
Display the reports on these performance counters by entering the Display
Performance (D P) or the Display History (D H) command sets into the MMI.
Display Performance
Enter the Display Performance (D P) command set to display performance
counters for the past hour. A screen similar to the following appears:
LTI T1 Interface Performance Log
3/03/95 1:37
Data for the past 37 Minutes
Errored Bursty Unavailable Loss Frame Error
ble Frame Slip
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.