Abstract:Ethernet-OAM is an Operation-Administration and Maintenance mechanism for Ethernet, which is mainly go on Ethernet-Continuity Check(ETH_CC), tracking and locating link fault. However, ETH-CC yields redundant link-fault alarms on the premise that a Maintenance Domain nests another. As a result, it is difficult to locate, separate and settle network faults with them. Ethernet-Alarm Indication Signal(ETH-AIS) be able to restrict ETH-CC producing redundant alarm. This paper is based on the ITU-T Y.1731 recommendation to improve ETH-AIS, including restrict redundant alarm information with high-speed, and reduce the amount of link-fault alarms and overcome the difficulty of locating, separating and settling network faults effectively. Finally to enhance the appliance of ETH-OAM and provide the technical support for Ethernet-operation.