ZyXEL VES1724-56B2 User Guide - Page 275

CFM MA

Page 275 highlights

Chapter 28 CFM •Loopback test - checks if the MEP port receives its LBR (Loop Back Response) from its target after it sends the LBM (Loop Back Message). If no response is received, there might be a connectivity fault between them. •Link trace test - provides additional connectivity fault analysis to get more information on where the fault is. In the link trace test, MIP ports also send the LTR (Link Trace Response) to response the source MEP port's LTM (Link Trace Message). If an MIP or MEP port does not respond to the source MEP, this may indicate a fault. Administrators can take further action to check and resume services from the fault according to the line connectivity status report. Refer to the Section 44.1 on page 370 to perform CFM actions. An example is shown next. A user reports his VDSL line link down. To check the problem, the administrator starts the link trace test from the A which is an MEP port to the B which is also an MEP port. Each aggregation MIP port between switches response the LTM packets and also forwards them to the next port. A fault occurs in the port C. A discovers the fault since it just gets the LTR packets from the ports flowing before the port C. Figure 167 MIP and MEP example A (port 2, MEP) (port 18, MIP) CPE (port 17, MIP) (port 18, MIP) C(port 17, MIP) B (port 8, MEP) 00:19:cb:14:25:37 28.2 CFM MA Click Advanced Application and CFM to open this screen. Use this screen to create an MA (Maintenance Association) under an MD level. You have to specify a name, a VLAN ID and its member ports. Refer to Section 28.1 on page 274 for more information about CFM. VES1724-56 User's Guide 275

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Chapter 28 CFM
VES1724-56 User’s Guide
275
•Loopback test - checks if the MEP port receives its LBR (Loop Back Response) from its target
after it sends the LBM (Loop Back Message). If no response is received, there might be a
connectivity fault between them.
•Link trace test - provides additional connectivity fault analysis to get more information on where
the fault is. In the link trace test, MIP ports also send the LTR (Link Trace Response) to
response the source MEP port’s LTM (Link Trace Message). If an MIP or MEP port does not
respond to the source MEP, this may indicate a fault. Administrators can take further action to
check and resume services from the fault according to the line connectivity status report. Refer
to the
Section 44.1 on page 370
to perform CFM actions.
An example is shown next. A user reports his VDSL line link down. To check the problem, the
administrator starts the link trace test from the
A
which is an MEP port to the
B
which is also an
MEP port. Each aggregation MIP port between switches response the LTM packets and also forwards
them to the next port. A fault occurs in the port
C
.
A
discovers the fault since it just gets the LTR
packets from the ports flowing before the port
C
.
Figure 167
MIP and MEP example
28.2
CFM MA
Click
Advanced Application
and
CFM
to open this screen. Use this screen to create an MA
(Maintenance Association) under an MD level. You have to specify a name, a VLAN ID and its
member ports. Refer to
Section 28.1 on page 274
for more information about CFM.
(port 2, MEP)
(port 18, MIP)
(port 17, MIP)
(port 18, MIP)
(port 17, MIP)
(port 8, MEP)
A
B
00:19:cb:14:25:37
CPE
C