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Cisco ONS 15454 Reference Manual, R7.0
78-17191-01
Chapter 2 Common Control Cards
2.7 2.7.3 Orderwire
The output contacts can be provisioned to close on a trigger or to close manually. The trigger can be a
local alarm severity threshold, a remote alarm severity, or a virtual wire:
• Local NE alarm severity: A hierarchy of Not Reported, Not Alarmed, Minor, Major, or Critical
alarm severities that you set to cause output closure. For example, if the trigger is set to Minor, a
Minor alarm or above is the trigger.
• Remote NE alarm severity: Same as the local network element (NE) alarm severity but applies to
remote alarms only.
• Virtual wire entities: You can provision any environmental alarm input to raise a signal on any
virtual wire on external outputs 1 through 4 when the alarm input is an event. You can provision a
signal on any virtual wire as a trigger for an external control output.
You can also program the output alarm contacts (external controls) separately. In addition to
provisionable triggers, you can manually force each external output contact to open or close. Manual
operation takes precedence over any provisioned triggers that might be present.
Note The number of inputs and outputs can be increased using the AEP. The AEP is connected to the shelf
backplane and requires an external wire-wrap panel.
2.7.3 Orderwire
Orderwire allows a craftsperson to plug a phoneset into an ONS 15454 and communicate with
craftspeople working at other ONS 15454s or other facility equipment. The orderwire is a pulse code
modulation (PCM) encoded voice channel that uses E1 or E2 bytes in section/line overhead.
The AIC-I allows simultaneous use of both local (section overhead signal) and express (line overhead
signal) orderwire channels on an SDH ring or particular optics facility. Express orderwire also allows
communication via regeneration sites when the regenerator is not a Cisco device.
You can provision orderwire functions with CTC similar to the current provisioning model for
DCC/GCC channels. In CTC, you provision the orderwire communications network during ring turn-up
so that all NEs on the ring can reach one another. Orderwire terminations (that is, the optics facilities
that receive and process the orderwire channels) are provisionable. Both express and local orderwire can
be configured as on or off on a particular SONET facility. The ONS 15454 supports up to four orderwire
channel terminations per shelf. This allows linear, single ring, dual ring, and small hub-and-spoke
configurations. Keep in mind that orderwire is not protected in ring topologies such as bidirectional line
switched rings (BLSRs) and path protection configurations.
Caution Do not configure orderwire loops. Orderwire loops cause feedback that disables the orderwire channel.
The ONS 15454 implementation of both local and express orderwire is broadcast in nature. The line acts
as a party line. Anyone who picks up the orderwire channel can communicate with all other participants
on the connected orderwire subnetwork. The local orderwire party line is separate from the express
orderwire party line. Up to four OC-N facilities for each local and express orderwire are provisionable
as orderwire paths.
Note The OC3 IR 4/STM1 SH 1310 card does not support the express orderwire channel.