Nortel Meridian 1 Option 11C, Administration And Maintenance

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Page 144 of 492 Chapter 4 — Network clocking
553-3011-311 Standard 7.0 May 1999
In Example 2, there is no digital connection to the local exchange. For TIE
lines between PBXs facilitated by a local exchange, clocking is derived from
the PBX, not the local exchange. When a second Digital loop is available, it
can be used as a Secondary Clock source in case the Primary Source fails.
Example 2
Isolated Private Network with Secondary Reference Clock
553-7562.EPS
Option 11 Option 11
Master Clock source:
Non-tracking (Free run) Clocking off Master:
Tracking on Primary
loop X and loop Y used
as a secondary clock
source
loop X loop X
loop Y loop Y
LD 60
TRCK FRUN
LD 73:
PREF <cr>
SREF <cr>
LD 60
TRCK PCK
LD 73:
PREF loop X
SREF loop Y
Slave Master clock