Nortel Networks Circuit Card 311 - Manual (Page 309)

Man-Machine E1 maintenance interface software 309
Figure 73
Display Status (D S) screen
Performance counters and reporting
The MMI monitors the performance of the E1 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, then reset to 0. Previous hour count results
are maintained for each of the previous 24 hours.
The LEI counts CRC-4 errors when CRC-4 is enabled and Bipolar Violations
(BPV) when CRC-4 is disabled. The performance criteria for which these
counts are maintained as follows:
• Errored seconds are seconds in which one or more CRC-4 / BPV errors,
or one or more out-of-frame errors in one second.
• Bursty seconds are seconds in which more than one and less than 320
CRC-4 / BPV errors in a second.
• Severely errored seconds are seconds in which more than 320 CRC-4 /
BPV errors, or one or more out-of-frames in a second.
• Unavailable seconds are seconds in which unavailable state starts with
10 consecutive severely errored seconds and ends with 10 consecutive
non-severely errored seconds (excluding the final 10 non-severely
errored seconds).
• Loss-of-frame seconds are seconds in which loss-of-frame or
loss-of-signal conditions exist for three consecutive seconds.
• Frame slip seconds are seconds in which one or more frame slips occur.
The MMI also maintains an overall error counter which is the sum of all
errors counted for the performance criteria listed above. The error counter
can only be cleared by entering the
Clear Error (C E) command. It
stops counting at 65,000. The error counter provides an easy method
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.