Specifications

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Cisco ONS 15530 Planning Guide
OL-7708-01
Chapter 2 Protection Schemes and Network Topologies
Client Based Line Card Protection
detected, and an acceptable standby signal is available, the system switches over to the standby signal.
The precise conditions that trigger a switchover based on signal failure or signal degrade are
configurable in the alarm threshold software.
Note Y-cable protection is not supported for ESCON aggregation cards and for 8-port multi-service
muxponders.
Y-Cable Protection Considerations
The following considerations apply when using Y-cable protection:
• Y-cable protection does not protect against failures of the client equipment. To protect against client
failures, protection should be implemented on the client equipment itself.
• Due to their lower optical power loss, we recommend using nonsplitter line cards for configurations
with Y-cable protection.
• Because of APS messaging conflicts, you cannot mix Y-cable protection and switch fabric based
protection on a 10-Gbps ITU tunable and non tunable trunk card or 10-Gbps uplink card.
• The APS software that supports y-cable protection can be configured as revertive or nonrevertive.
After a switchover, the active traffic can be put back on the previously failed working fiber, once the
fault has been remedied, either automatically (revertive) or through manual intervention
(nonrevertive).
• Y-cable protected configurations allow monitoring of the protection fiber without the OSC.
• Up to four channels can be Y-cable protected on a single shelf when the OSC is not supported; if
the OSC is supported, up to three channels can be y-cable protected on a single shelf.
For rules on how to configure the shelf for Y-cable protection, see Chapter 3, “Shelf Configuration
Rules.” For instructions on configuring the software for y-cable protection, refer to the
Cisco ONS 15530 Configuration Guide.
Client Based Line Card Protection
While y-cable protection protects against failures in the transponder line cards and the 8-port Fibre
Channel/Gigabit Ethernet aggregation cards or on the fiber, the client still remains vulnerable. For some
applications additional protection of the client equipment may be desirable for transponder line card,
ESCON aggregation card, and 8-port FC/GE aggregation card applications. The client equipment
transmits and receives two separate signals that it monitors. Switchovers are under control of the client
rather than the protection mechanisms on the Cisco ONS 15530.