802.1ag

IEEE 802.1ag (also CFM) (IEEE Standard for Local and Metropolitan Area Networks Virtual Bridged Local Area Networks Amendment 5: Connectivity Fault Management) is a standard defined by IEEE. It defines protocols and practices for OAM (Operations, Administration, and Maintenance) for paths through 802.1 bridges and local area networks (LANs). It is an amendment to IEEE 802.1Q-2005 and was approved in 2007.

IEEE 802.1ag is largely identical with ITU-T Recommendation Y.1731, which additionally addresses performance monitoring.

The standard:

The document defines various terms:

IEEE 802.1ag Ethernet CFM (Connectivity Fault Management) protocols comprise three protocols that work together to help administrators debug Ethernet networks. They are:

ITU-T Y.1731 additionally supports the following:

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