VMG1312-B10C User’s Guide
265
C
H A P T E R
3 6
Diagnostic
36.1 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.
36.1.1 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
screen lets you send an ATM OAM (Operation, Administration and Maintenance)
packet to verify the connectivity of a specific PVC. (
36.2 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.
Содержание VMG1312-B10C
Страница 4: ...Contents Overview VMG1312 B10C User s Guide 4 Diagnostic 265 Troubleshooting 271 ...
Страница 14: ...Table of Contents VMG1312 B10C User s Guide 14 ...
Страница 15: ...15 PART I User s Guide ...
Страница 16: ...16 ...
Страница 22: ...Chapter 1 Introducing the Device VMG1312 B10C User s Guide 22 ...
Страница 33: ...33 PART II Technical Reference ...
Страница 34: ...34 ...
Страница 64: ...Chapter 5 Broadband VMG1312 B10C User s Guide 64 ...
Страница 100: ...Chapter 6 Wireless VMG1312 B10C User s Guide 100 ...
Страница 124: ...Chapter 7 Home Networking VMG1312 B10C User s Guide 124 ...
Страница 166: ...Chapter 10 Network Address Translation NAT VMG1312 B10C User s Guide 166 ...
Страница 176: ...Chapter 12 Interface Group VMG1312 B10C User s Guide 176 ...
Страница 192: ...Chapter 14 Firewall VMG1312 B10C User s Guide 192 ...
Страница 198: ...Chapter 16 Parental Control VMG1312 B10C User s Guide 198 ...
Страница 208: ...Chapter 18 Certificates VMG1312 B10C User s Guide 208 ...
Страница 211: ...Chapter 19 VPN VMG1312 B10C User s Guide 211 Figure 121 IPSec VPN Add ...
Страница 224: ...Chapter 20 Log VMG1312 B10C User s Guide 224 ...
Страница 234: ...Chapter 24 IGMP Status VMG1312 B10C User s Guide 234 ...
Страница 238: ...Chapter 25 xDSL Statistics VMG1312 B10C User s Guide 238 ...
Страница 242: ...Chapter 27 User Account VMG1312 B10C User s Guide 242 ...
Страница 248: ...Chapter 30 TR 064 VMG1312 B10C User s Guide 248 ...
Страница 252: ...Chapter 31 Time Settings VMG1312 B10C User s Guide 252 ...
Страница 264: ...Chapter 35 Configuration VMG1312 B10C User s Guide 264 ...
Страница 270: ...Chapter 36 Diagnostic VMG1312 B10C User s Guide 270 ...
Страница 288: ...Appendix B Legal Information VMG1312 B10C User s Guide 288 ...