Alcatel-Lucent 7710 SR SONET, Configuration Manual

Page: 114 / 496

802.3ah OAM
Page 114 7710 SR OS Interface Configuration Guide
802.3ah OAM
802.3ah Clause 57 (EFM OAM) defines the Operations, Administration, and Maintenance (OAM)
sub-layer, which provides mechanisms useful for monitoring link operation such as remote fault
indication and remote loopback control. In general, OAM provides network operators the ability to
monitor the health of the network and quickly determine the location of failing links or fault
conditions. EFM OAM described in this clause provides data link layer mechanisms that
complement applications that may reside in higher layers.
OAM information is conveyed in slow protocol frames called OAM protocol data units
(OAMPDUs). OAMPDUs contain the appropriate control and status information used to monitor,
test and troubleshoot OAM-enabled links. OAMPDUs traverse a single link, being passed between
peer OAM entities, and as such, are not forwarded by MAC clients (like bridges or switches).
The following EFM OAM functions are supported:
• EFM OAM capability discovery.
• Active and passive modes.
• Remote failure indication — Handling of critical link events (link fault, dying gasp, etc.)
• Loopback — A mechanism is provided to support a data link layer frame-level loopback
mode. Both remote and local loopback modes are supported.
• EFM OAMPDU tunneling.
• High resolution timer for EFM OAM in 100ms interval (minimum).