1+1 line protection switching
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Overview
Metropolis
®
DMXplore supports SONET standard 1+1, unidirectional,
nonrevertive line protection switching on high-speed OC-3 and OC-12
optical interfaces. 1+1 is the default application in Metropolis
®
DMXplore. Protection switches are initiated by automatically detected
faults in the circuit packs/optical lines and/or by external commands
from the WaveStar
®
CIT or OS interface.
1+1 protection switching is provisioned from the WaveStar
®
CIT
System View menu, the
Configuration
→
Equipment
menu and its
supporting displays.
Protection switch priorities are set from the WaveStar
®
CIT System
View menu,
Fault
→
Protection Switch
menu and its supporting
displays.
Automatic line protection
In multispan applications each OC-N span switches independently. For
example, in hubbing applications, a switch on the central office-to-hub
span does not cause switches on any of the hub-to-remote spans.
Similarly, a line switch on a hub-to-remote span will not propagate to
other hub-to-remote or central office-to-hub spans.
1+1 application mode
To support a 1+1 protection compatibility, the OC-N ring interface
must be provisioned to the 1+1 mode for 1+1 applications using the
Configuration
→
Equipment
or the
ent-ocn
command.
Line protection switching can also be controlled by
Fault
→
Protection Switch
or using the command builder and the
opr-protnsw-oc3
and
rls-protnsw-oc12
TL1 commands.
For more information on setting up protection switching, refer to the
Metropolis
®
DMXplore Access Multiplexer User Operations Guide,
365-372-332.
Protection switching
priorities
Metropolis
®
DMXplore supports a system-wide 1+1 protection switch
priority for optical interfaces. The priority parameter
(UNIPROTPRIO) is provisioned by selecting the
Configuration
→
Equipment
command, then highlighting Metropolis(R) DMXplore,
clicking Provision, and provisioning 1+1 Protection Priority to be
Forced or Signal Failure.
The following table lists the 1+1 line protection switch priorities (in
descending order of priority) used by Metropolis
®
DMXplore when
Maintenance overview
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Lucent Technologies
365-372-333 R2.1
Issue 4, June 2005