Network Router User Manual

5-13
Cisco ONS 15530 Configuration Guide and Command Reference
78-14227-01, Cisco IOS Release 12.1(10)EV2
Chapter 5 Configuring Transponder Line Card Interfaces
About Laser Shutdown
About Laser Shutdown
To avoid operator injury or transmission of unreliable data, or to provide quick path switchover, the
Cisco ONS 15530 supports mechanisms to automatically shut down transponder line card lasers. The
three types of laser shutdown mechanisms are:
• Forward laser control
• OFC safety protocol
• Laser safety control
About Forward Laser Control
When loss of light occurs on the receive signal of a transparent or wave interface, the corresponding
transmitting laser on the other side of the transponder line card continues to function and might send
unreliable information to the client. Forward laser control provides a means to quickly shut down a
transmitting laser when such a receive signal failure occurs (see Figure 5-1). The receive signal loss of
light can result from a failure in the client equipment, a receiver failure in the transponder line card, or
a laser shutdown on another node in the network.
This feature is convenient for configurations, such as Sysplex, where signal protection is performed in
the client hardware and a quick laser shutdown causes a quick path switchover.
Figure 5-1 Forward Laser Control Overview
Laser shuts down
Laser shuts down
Loss of light detected
oss of light detected
Client side
Transponder module
Trunk side
Tx
Rx
Transmit laser
Transmit laser
Receiver
Receiver
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