The IEEE 802.3ah Ethernet in First Mile (EFM) specifies the protocols and ethernet interfaces for using ethernet access links as a first-mile technology.
Using ethernet in the EFM solution, the user gains broadcast Internet access, in addition to services like Layer 2 transparent LAN services, voice services over ethernet access networks, video, and multicast applications. This is reinforced by security and quality of service to build a scalable network. The in-band management specified by this standard defines the operations, administration and maintenance (OAM) mechanism needed for the advanced monitoring and maintenance of ethernet links in the first mile.
The 802.3ah protocol activities are classified into three layers, namely transport layer, connectivity layer and service layer. The transport layer 802.3ah protocol provides single-link OAM capabilities, offering an opportunity to create the operations and OAM sub-layer within the data-link layer. The connectivity layer provides utilities for monitoring and troubleshooting ethernet links.
The data-link layer protocol targets the last-mile applications. Service providers can use it for demarcation point OAM services. The 802.3ah protocol resolves validation and testing problems. Using the ethernet demarcation, service providers can additionally manage the remote device without utilizing an IP layer.
Note
Link monitoring functionality is not supported.Link OAM is a link-level protocol and is supported on physical interfaces.
On SLX-OS device, Link OAM configuration is allowed on VPLS and VLL endpoint(s). Note that the support for VPLS and VLL endpoints is available only when Link OAM is configured on the link between CE (passive) and PE (active).
Note
Currently, the support is only for Information and loopback Control OAMPDUsNetwork devices are identified along with their OAM configuration and capabilities in the discovery phase of the EFM-OAM. Remote loopback configuration and OAM mode (active/passive) capability are supported during this phase.
Note
There is no pre-requisite or support for configuration to consider the discovery status as unsatisfied. Hence any capability received from the peer will be deemed as satisfied and will wait for the peer to become stable before marking the Link OAM status as up.Remote loopback allows you to estimate if a network segment can satisfy an SLA and helps you to ensure quality of links during installation and troubleshooting. An OAM entity can put its remote entity into loopback mode using a loopback control OAMPDU. The remote-loop-back command allows you to start and stop the remote loopback on peer that is connected to local ethernet interface specified.
device# link-oam remote-loop-back ethernet 1/1 start
device# link-oam remote-loop-back ethernet 1/1 stop
Note
We recommend that when in loopback mode, you should remove the loopback ports from the active network topology to reduce the impact of protocol flaps.For more information on commands, please refer to the Extreme SLX-OS Command Reference Guide.