Avaya S8700 Maintenance Manual page 2235

SYNC (Port-Network Synchronization)
When over half of the DS1 and UDS1 circuit packs administered as slip enabled
are experiencing slips, and the primary or secondary synchronization reference is
the current synchronization reference, synchronization will try the other
administered synchronization reference.
In situations where one or many circuit packs in the system are experiencing slips,
the problem could be with the synchronization reference, with individual circuit
packs, or with phase modulation of the transmitted digital bit streams due to
environmental variations of the transmission facilities (such as temperature
variations that affect the electrical length of a transmission line). The circuit packs
that can experience slips and the associated error log entry for slips are as follows
in Table 8-590:
Table 8-590. Error Log Entries for Slip Errors
Circuit Pack
DS1 Interface
Expansion Interface
Switch Node Interface
IPSI's Tone-Clock circuit or Tone-Clock TDM-CLK
UDS1 Interface
When slips occur on any of these circuit packs, first consult the individual circuit
pack's section in this manual. If slips occur in small amounts, they may be due to
environmental conditions as previously described. If no service degradation is
occurring, no action is necessary. Whenever the system switches
synchronization sources, slips can be expected from DS1-BD, UDS1-BD, and
EXP-INTF circuit packs. If service degradation occurs, after following the repair
steps in the individual section, use the following trouble shooting techniques.
Table 8-591
hardware problems that cause those slips.
Table 8-591. Slips and Related Circuit Packs
Circuit Pack Reporting Slips
DS1 Interface
Expansion Interface
Switch Node Interface
IPSI's Tone-Clock or Tone-Clock Current DS1 reference
UDS1 Interface
555-233-143
lists circuit packs that can report slips and related circuit packs whose
Associated Circuit Packs that Can Cause Slips
Active Tone-Clock in same PN
Active Tone-Clock in same PN or circuit pack at
opposite end of fiber or metallic connection
Circuit pack at opposite end of fiber or metallic
connection, or active Switch Node Clock circuit pack
in same switch node carrier
Active Tone-Clock in same PN
Error Log Name Error Log Entry for Slips
DS1-BD 3073 – 3160
EXP-INTF 2305
SNI-BD 1537
1025
UDS1-BD 3073 – 3160
Issue 1 May 2002 8-1513