Nortel Communication Server 1000S Maintenance Manual page 144

Page 144 of 210
Frame alignment
553-3001-517 Standard 2.00
1.5 Mb DTI/PRI maintenance
Table 38
Frame slip improvement timers (Part 2 of 2)
DTA 029 - Frame slip improvement timer has expired, Slip
Rate Improvement Criteria has been met. Trunks are being
returned to service.
SRMM 1-(2)-127
Loss of frame alignment occurs when the DTI/PRI card stops receiving the
framing pattern on the DS-1 byte stream for a pre-defined period of time
(three seconds). See Figure 23 on
condition can occur as a result of the far end of the T1 span going completely
out-of service or any other reason resulting in losing the incoming DS-1 pulse
stream.
Loss of frame alignment thresholds
DTI/PRI hardware detects out-of-frame conditions. Running the midnight
routines prints the number of occurrences when frame alignment was lost and
clears the counters.
September 2004
page 145 and Figure 24 on page 146. This