7-5
Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter7 Card Protection
7.4 External Switching Commands
Figure7-3 ONS 15454 SDH Cards in an Unprotected Configuration
7.4 External Switching Commands
The external switching commands on the ONS 15454 SDH are Manual, Force, and Lock out. If you
choose a Manual switch, the command will switch traffic only if the path has an error rate less than the
signal degrade (SD) bit error rate threshold. A Force switch will switch traffic even if the path has SD
or signal fail (SF) conditions; however, a Force switch will not override an SF on a 1+1 protectio n
channel. A Force switch has a higher priority than a Manual switch. Lock outs, which prevent traffic
from switching to the protect port under any circumstance , can only be applied to protect cards (in 1+1
configurations) . Lockouts have the highest priority.
Note Force and Manual switches do not apply to 1:1 protection groups; these ports have a single switch
command.
Another way to inhibit protection switching in a 1+1 configuration is to apply a lock on to the working
port. A working port with a lock on applied cannot switch traffic to the protect port in the protection
group (pair). In 1:1 protection groups, working or protect ports can have a lock on.
Unprotected
83627
FMEC
FMEC
FMEC
FMEC
FMEC
MIC-A/P
MIC-T/C/P
FMEC
FMEC
FMEC
FMEC
FMEC
Timing, Comm., and Control
Cross Connect
Cross Connect
Timing, Comm., and Control
Working
Working (not electric)
Working
Working
Working
Working (not electric)
Working
Working
Working
Working
Working
Working
AIC-I (optional)
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