DEFINITY Enterprise Communications Server Release 6
Maintenance for R6vs/si
555-230-127 Issue 1
August 1997
Maintenance Object Repair Procedures
Page10-1214SYNC (Synchronization)
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reference does not provide a valid timing signal, Synchronization M aintenance
switches to the secondary reference. Both the primary and secondary
references must reside in the same port network, bu t there is no restriction
as to in which port network both must reside (that is, both references may
be in an EPN). The recommended placement of the references is in the PPN .
There are two kinds of Stratum 4 synchronization that are sup ported: Type I and
Type II. Stratum 4 type I is more stable than Type II and p rovides some switching
capability at the hardware level. Stratum 4 Type II operation is the only
synchronization strata provided by Generic 1. It is important to note that Stratum
4 Type I operation is not possible when one or both of the DS1 interface circuit
packs providing the reference sources is a TN722. Both must be the TN767 or
TN464 (suffix C or higher).
Stratum 3 Synchronization
The following diagram may help you to understand the sy nchronization
components needed for Stratum 3 synchronization.
NOTE:
This is only one possible configuration.