VMG1312-B10A User’s Guide
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Diagnostic
35.1 Overview
The Diagnostic screens display information to help you identify problems with the Device.
The route between a CO VDSL switch and one of its CPE may go through switches owned by
independent organizations. A connectivity fault point generally takes time to discover and impacts
subscriber’s network access. In order to eliminate the management and maintenance efforts, IEEE
802.1ag is a Connectivity Fault Management (CFM) specification which allows network
administrators to identify and manage connection faults. Through discovery and verification of the
path, CFM can detect, analyze and isolate connectivity faults in bridged LANs.
35.1.1 What You Can Do in this Chapter
• The Ping & TraceRoute & NsLookup screen lets you ping an IP address or trace the route
packets take to a host (
• The 802.1ag screen lets you perform CFM actions (
).
• The OAM Ping Test screen lets you send an ATM OAM (Operation, Administration and
Maintenance) packet to verify the connectivity of a specific PVC. (
35.2 What You Need to Know
The following terms and concepts may help as you read through this chapter.
How CFM Works
A Maintenance Association (MA) defines a VLAN and associated Maintenance End Point (MEP) ports
on the device under a Maintenance Domain (MD) level. An MEP port has the ability to send
Connectivity Check Messages (CCMs) and get other MEP ports information from neighbor devices’
CCMs within an MA.
CFM provides two tests to discover connectivity faults.
• Loopback test - checks if the MEP port receives its Loop Back Response (LBR) from its target
after it sends the Loop Back Message (LBM). 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. If an 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.
Summary of Contents for VWG1312-B10A
Page 2: ......
Page 8: ...Contents Overview VMG1312 B10A User s Guide 8 Troubleshooting 291 ...
Page 18: ...Table of Contents VMG1312 B10A User s Guide 18 ...
Page 19: ...19 PART I User s Guide ...
Page 20: ...20 ...
Page 34: ...Chapter 2 The Web Configurator VMG1312 B10A User s Guide 34 ...
Page 39: ...Chapter 4 Tutorials VMG1312 B10A User s Guide 39 7 Click Apply to save your settings ...
Page 79: ...79 PART II Technical Reference ...
Page 80: ...80 ...
Page 168: ...Chapter 9 Routing VMG1312 B10A User s Guide 168 ...
Page 186: ...Chapter 10 Quality of Service QoS VMG1312 B10A User s Guide 186 ...
Page 212: ...Chapter 13 Interface Group VMG1312 B10A User s Guide 212 ...
Page 228: ...Chapter 15 Firewall VMG1312 B10A User s Guide 228 ...
Page 234: ...Chapter 17 Parental Control VMG1312 B10A User s Guide 234 ...
Page 244: ...Chapter 19 Certificates VMG1312 B10A User s Guide 244 ...
Page 248: ...Chapter 20 Log VMG1312 B10A User s Guide 248 ...
Page 252: ...Chapter 21 Traffic Status VMG1312 B10A User s Guide 252 ...
Page 258: ...Chapter 24 IGMP Status VMG1312 B10A User s Guide 258 ...
Page 262: ...Chapter 25 xDSL Statistics VMG1312 B10A User s Guide 262 ...
Page 264: ...Chapter 26 User Account VMG1312 B10A User s Guide 264 ...
Page 270: ...Chapter 29 TR 064 VMG1312 B10A User s Guide 270 ...
Page 274: ...Chapter 30 Time Settings VMG1312 B10A User s Guide 274 ...
Page 280: ...Chapter 32 Logs Setting VMG1312 B10A User s Guide 280 ...
Page 298: ...Chapter 36 Troubleshooting VMG1312 B10A User s Guide 298 ...
Page 338: ...Appendix C Pop up Windows JavaScripts and Java Permissions VMG1312 B10A User s Guide 338 ...
Page 352: ...Appendix D Wireless LANs VMG1312 B10A User s Guide 352 ...
Page 368: ...Appendix G Legal Information VMG1312 B10A User s Guide 368 ...
Page 376: ...VMG1312 B10A User s Guide 376 Index ...