ETH-CFM

The IEEE and the ITU-T have cooperated to define the protocols, procedures and managed objects to support service based fault management. Both IEEE 802.1ag standard and the ITU-T Y.1731 recommendation support a common set of tools that allow operators to deploy the necessary administrative constructs, management entities and functionality, Ethernet Connectivity Fault Management (ETH-CFM). The ITU-T has also implemented a set of advanced ETH-CFM and performance management functions and features that build on the proactive and on demand troubleshooting tools.

CFM uses Ethernet frames and is distinguishable by ether-type 0x8902. In specific cases, the different functions use a reserved multicast Layer 2 MAC address that could also be used to identify specific functions at the MAC layer. The multicast MAC addressing is not used for every function or in every case. The Operational Code (OpCode) in the common CFM header is used to identify the PDU type carried in the CFM packet. CFM frames are only processed by IEEE MAC bridges.

IEEE 802.1ag and ITU-T Y.1731 functions that are implemented are available on the SR and ESS platforms.

This section of the guide provides configuration example for each of the functions. It also provides the various OAM command line options and show commands to operate the network. The individual service guides provides the complete CLI configuration and description of the commands to build the necessary constructs and management points.

Table: ETH-CFM acronym expansions lists and expands the acronyms used in this section.

Table: ETH-CFM acronym expansions
Acronym Expansion Supported platform

1DM

One way Delay Measurement (Y.1731)

All

AIS

Alarm Indication Signal

All

BNM

Bandwidth Notification Message (Y.1731 sub OpCode of GNM)

All

CCM

Continuity check message

All

CFM

Connectivity fault management

All

CSF

Client Signal Fail (Receive)

All

DMM

Delay Measurement Message (Y.1731)

All

DMR

Delay Measurement Reply (Y.1731)

All

ED

Ethernet Defect (Y.1731 sub OpCode of MCC)

All

GNM

Generic Notification Message

All

LBM

Loopback message

All

LBR

Loopback reply

All

LMM

(Frame) Loss Measurement Message

Platform specific

LMR

(Frame) Loss Measurement Response

Platform specific

LTM

Linktrace message

All

LTR

Linktrace reply

All

MCC

Maintenance Communication Channel (Y.1731)

All

ME

Maintenance entity

All

MA

Maintenance association

All

MD

Maintenance domain

All

MEP

Maintenance association endpoint

All

MEP-ID

Maintenance association endpoint identifier

All

MHF

MIP half function

All

MIP

Maintenance domain intermediate point

All

OpCode

Operational Code

All

RDI

Remote Defect Indication

All

TST

Ethernet Test (Y.1731)

All

SLM

Synthetic Loss Message

All

SLR

Synthetic Loss Reply (Y.1731)

All

VSM

Vendor Specific Message (Y.1731)

All

VSR

Vendor Specific Reply (Y.1731)

All