ZyXEL Communications OLT2406, User Manual

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Chapter 95 CFM Commands
OLT2406 User’s Guide
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95
CFM Commands
95.1 CFM Overview
Use these commands to configure the Connectivity Fault Management (CFM) on the OLT.
The route between two users may go through aggregated switches, routers and/or DSLAMs owned by
independent organizations. A connectivity fault point generally takes time to discover and impacts
subscribers’ network access. IEEE 802.1ag is a Connectivity Fault Management (CFM) specification
which allows network administrators to identify and manage connection faults in order to ease
management and maintenance. Through discovery and verification of the path, CFM can detect and
analyze connectivity faults in bridged LANs.
The figure shown below is an example of a connection fault between switches in the service provider’s
network. CFM can be used to identify and management this kind of connection problem.
Figure 288 Connectivity Fault Example
95.1.1 How CFM Works
CFM sends pro-active Connectivity Check (CC) packets between two CFM-aware devices in the same
MD (Maintenance Domain) network. An MA (Maintenance Association) defines a VLAN and associated
ports on the device under an MD level. In this MA, a port can be an MEP (Maintenance End Point) port
or an MIP (Maintenance Intermediate Point) port.
•MEP port - has the ability to send pro-active connectivity check (CC) packets and get other MEP
port information from neighbor switches’ CC packets within an MA.
CPE
Service Provider Network
CPE
VDSL
VDSL