IMC Networks IE-iMcV-MultiWay, Руководство по эксплуатации

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Operations, Administration and Maintenance (OAM)
OAM is a general term used in network management and is typically applied to a
series of standard protocols for installing, monitoring, and troubleshooting
Metropolitan Area Networks.
When applied to Ethernet – OAM is typically assumed to refer to the layer 2 (MAC
layer), management protocols, specifically 802.3ah and 802.1ag. Layer 2
management protocols do not need higher level transport protocols to operate, OAM
data is transferred in standard multicast Ethernet frames.
802.3ah OAM:
(LINK-OAM)
Is a point-to-point protocol designed to verify a specific link
between two directly connected devices (over copper or fiber),
which support 802.3ah OAM. One device must be configured
to be an active OAM device, the other a passive (typically the
core switch would be the active device, the end device passive).
802.3ah OAM provides link status, remote fault detection and
the ability to initiate a loopback circuit.
802.1ag:
(SERVICE-OAM)
Often referred to as Connectivity Fault Management (CFM), is an
end-to-end protocol designed to verify a specific network path
between two devices that may well be in different geographical
locations. CFM allows the network operator to administer,
monitor and debug the network using continuity check (a heart
beat message), link trace (similar to traceroot, but operating at
the MAC layer) and finally loopback (can be likened to a layer 2
ping).