Nortel Modular ICS 7.1, Инструкция по установке

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/ Hardware
Modular ICS 7.1 Installer Guide N0130943 02
Clock Src
Installer password required
Systems with digital interfaces need to synchronize to the
network in order to function. Synchronization is performed in
a hierarchical way, where each device/switch obtains the
network clock from the device/or switch above it in the
synchronization hierarchy and passes the network clock to the
device/switch below it in the synchronization hierarchy. The
synchronization levels are referred to as strata.
Norstar systems are stratum 4E equipment and are usually
used as termination points in a network.
For each on-core DTI, choose one of the following settings:
• Primary reference : The DTI obtains the timing reference
from the network, to which the system synchronizes. This
is the default value for the DTI in slot 1 in the ICS. If the
system is configured with a DTI card that has been
configured as PRI, the setting should be set to
Primary
.
• Secondary reference (
Secndry
) : The DTI acts as a
standby reference. If there are excessive errors on the
primary reference T1 link, or the DTI designated as
primary reference fails, this DTI will obtain the timing
reference from the network, which the system
synchronizes to. This is the default value for the DTI in slot
2 in the ICS.
• Timing master (
TimeMst
) : The DTI does not obtain
timing from the network, but transmits the systems timing
to equipment connected to it.
WARNING:
An off-core DTI needs to be left
on free run