IEEE 802.1ag

IEEE 802.1ag (aka "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 management.

The standard:

• Defines maintenance domains, their constituent maintenance points, and the managed objects required to create and administer them
• Defines the relationship between maintenance domains and the services offered by VLAN-aware bridges and provider bridges
• Describes the protocols and procedures used by maintenance points to maintain and diagnose connectivity faults within a maintenance domain;
• Provides means for future expansion of the capabilities of maintenance points and their protocols