4Configuring Ethernet OAMEthernet OAM overviewEthernet Operation, Administration and Maintenance (OAM) is a tool that monitors Layer 2 link statusand addresses common link-related issues on the "last mile." You can use it to monitor the status of thepoint-to-point link between two directly connected devices.Major functions of Ethernet OAMEthernet OAM provides the following functions:• Link performance monitoring—Monitors the performance indices of a link, including packet loss,delay, and jitter, and collects traffic statistics of various types• Fault detection and alarm—Checks the connectivity of a link by sending OAM protocol data units(OAMPDUs) and reports to the network administrators when a link error occurs• Remote loopback—Checks link quality and locates link errors by looping back OAMPDUsEthernet OAMPDUsEthernet OAM works on the data link layer. Ethernet OAM reports the link status by periodicallyexchanging OAMPDUs between devices so that the administrator can effectively manage the network.Ethernet OAMPDUs fall into the following types: Information, Event Notification, and Loopback Control.Figure 1 Formats of different types of Ethernet OAMPDUsTable 4 Fields in an OAMPDUField DescriptionDest addrDestination MAC address of the Ethernet OAMPDUIt is a slow protocol multicast address, 0180c2000002. Bridges cannot forwardslow protocol packets, so Ethernet OAMPDUs cannot be forwarded.Source addr Source MAC address of the Ethernet OAMPDUIt is the bridge MAC address of the sending side and is a unicast MAC address.Type Type of the encapsulated protocol in the Ethernet OAMPDUThe value is 0x8809.
