Instruction manual

Maintenance
The 800 CO-BRI Module as the Clock Source
If the 800 CO-BRI module functions as the local clock source, the maintenance
software monitors all frame slip counters associated with all the activated Digital
Subscriber Line (DSL) ports on the module. (A DSL port is activated when it has
at least one Service Profile Identifier assigned to it.) When the counters reach an
alarm level, the local clock is considered to be defective and is deactivated; the
software switches the clock to another module, in the order described above.
When the slip alarm is removed, the software switches the clock back to the 800
CO-BRI module, if the module has a higher clock priority than the source
currently being used.
A DSL Port as the Clock Source
If one of the DSL ports is used as the loop clock source, the maintenance
software monitors that DSL’s frame slip counter. When the counter reaches an
alarm level, the maintenance software deactivates the DSL port as the clock
source and finds another clock source, in the order described above. This error
condition is called “BRI SLIPS >88” and is a transient error.
When the software detects a loss of synchronization or a network deactivate
condition, called “BRI LOSS OF SYNC” or “BRI NET DEACTIVATE, ” the software
deactivates the DSL port as a clock source and finds another source. These
errors are permanent errors.
When the maintenance software detects that the above DSL port alarms have
been removed, it switches the clock source back to the DSL port if the port has a
higher clock priority than the source currently being used.
6-14 BRI Module and Clock Synchronization