The Ethernet Client Signal Fail feature (ETH-CSF) is an enhancement to the existing performance-monitoring functionality as documented in ITU-T standard G.8013/Y.1731.
Note
For text of the standard, see https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-G.8013-201508-I!!PDF-E&type=items
This feature is used by a Maintenance Entity Group End Point (MEP) to propagate the detection of a failure or defect event in an Ethernet client signal to a peer Remote MEP (RMEP) when the client itself does not support appropriate fault detection, defect detection, or propagation mechanisms such as Ethernet Continuity Check (ETH-CC) or Ethernet Alarm Indication Signal (ETH-AIS). The ETH-CSF messages propagate in the direction from the Ethernet MEP, associated with the ingress client port detecting the failure or defect event, to the Ethernet peer RMEP.
Note
For supporting documentation, refer to "Y.1731 Performance Monitoring" in the "Operation, Administration, and Maintenance" chapter in the Extreme SLX-OS Monitoring Configuration Guide.