![background image](http://html1.mh-extra.com/html/zyxel-communications/msc1000g-series/msc1000g-series_user-manual_945543164.webp)
Chapter 6 Diagnostic Screens
Management Switch Card User’s Guide
164
CFM provides two tests to discover connectivity faults.
• Loopback test - similar to “pinging” a computer. A 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 - similar to the “traceroute” function. A link trace test provides additional
connectivity fault analysis to obtain more information on where the fault is. In the link trace test,
MIP ports also send a LTR (Link Trace Response) in response to 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.
An example is shown next. A user reports he cannot access the Internet. 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 aggregated devices 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 87
MIP and MEP Example
6.2 LDM Test Screen (DELT)
Click
Diagnostic > LDM
in the navigation panel to display this screen. Use this screen to perform
loop diagnostics (LDM stands for Loop Diagnostic Mode) on an ADSL2, ADSL2+ or VDSL port. This
is a Dual End Loop Test (DELT) that acts on a per-tone basis. A DELT provides details about the line
condition. The subscriber device must also support DELT in order to perform this. See ITU-T G933.2
for more information. This feature is applicable for ALC line cards only.
(port 2, MEP)
(port 18, MIP)
(port 8, MEP)
B
C
(port 17, MIP)
A
Summary of Contents for MSC1000G Series
Page 38: ...Table of Contents Management Switch Card User s Guide 38...
Page 39: ...39 PART I Introduction...
Page 40: ...40...
Page 54: ...Chapter 1 Getting to Know Your MSC Management Switch Card User s Guide 54...
Page 61: ...61 PART II Web Configurator...
Page 62: ...62...
Page 80: ...Chapter 3 The Web Configurator Management Switch Card User s Guide 80...
Page 162: ...Chapter 5 Alarm Screens Management Switch Card User s Guide 162...
Page 178: ...Chapter 6 Diagnostic Screens Management Switch Card User s Guide 178...
Page 184: ...Chapter 7 Maintenance Screens Management Switch Card User s Guide 184...
Page 204: ...Chapter 8 Multicast Screens Management Switch Card User s Guide 204...
Page 226: ...Chapter 9 Subscriber Port Setup Screens Management Switch Card User s Guide 226...
Page 227: ...Chapter 9 Subscriber Port Setup Screens Management Switch Card User s Guide 227...
Page 330: ...Chapter 10 IMA Screens Management Switch Card User s Guide 330...
Page 412: ...Chapter 11 Profile Screens Management Switch Card User s Guide 412...
Page 512: ...Chapter 12 Statistics Screens Management Switch Card User s Guide 512...
Page 560: ...Chapter 13 Switch Screens Management Switch Card User s Guide 560...
Page 598: ...Chapter 15 VLAN Screens Management Switch Card User s Guide 598...
Page 636: ...Chapter 16 VoIP Management Switch Card User s Guide 636...
Page 638: ...Chapter 17 Config Save Management Switch Card User s Guide 638...
Page 639: ...639 PART III Commands...
Page 640: ...640...
Page 646: ...Chapter 18 Commands Management Switch Card User s Guide 646...
Page 682: ...Chapter 19 acl Commands Management Switch Card User s Guide 682...
Page 690: ...Chapter 20 alarm Commands Management Switch Card User s Guide 690...
Page 696: ...Chapter 22 config Commands Management Switch Card User s Guide 696...
Page 754: ...Chapter 28 multicast Commands Management Switch Card User s Guide 754...
Page 840: ...Chapter 29 port Commands Management Switch Card User s Guide 840...
Page 924: ...Chapter 30 profile Commands Management Switch Card User s Guide 924...
Page 926: ...Chapter 31 redundant Commands Management Switch Card User s Guide 926...
Page 1062: ...Chapter 35 vlan Commands Management Switch Card User s Guide 1062...
Page 1103: ...1103 PART IV Troubleshooting Specifications Appendices and Index...
Page 1104: ...1104...
Page 1134: ...Chapter 39 Product Specifications Management Switch Card User s Guide 1134...
Page 1146: ...Appendix B Legal Information Management Switch Card User s Guide 1146...