Chapter 25 Diagnostic
P-2812HNU-51c User’s Guide
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25.5 The OAM Ping Test Screen
Click Maintenance > Diagnostic > OAM Ping Test to open the screen shown
next. Use this screen to perform an OAM (Operation, Administration and
Maintenance) F4 or F5 loopback test on a PVC. The P-2812HNU-51c sends an OAM
F4 or F5 packet to the DSLAM or ATM switch and then returns it to the P-
2812HNU-51c. The test result then displays in the text box.
ATM sets up virtual circuits over which end systems communicate. The
terminology for virtual circuits is as follows:
Figure 162
Virtual Circuit Topology
Think of a virtual path as a cable that contains a bundle of wires. The cable
connects two points and wires within the cable provide individual circuits between
the two points. In an ATM cell header, a VPI (Virtual Path Identifier) identifies a
link formed by a virtual path; a VCI (Virtual Channel Identifier) identifies a
channel within a virtual path. A series of virtual paths make up a virtual circuit.
F4 cells operate at the virtual path (VP) level, while F5 cells operate at the virtual
channel (VC) level. F4 cells use the same VPI as the user data cells on VP
connections, but use different predefined VCI values. F5 cells use the same VPI
and VCI as the user data cells on the VC connections, and are distinguished from
data cells by a predefinded Payload Type Identifier (PTI) in the cell header. Both F4
flows and F5 flows are bidirectional and have two types.
• segment F4 flows (VCI=3)
• end-to-end F4 flows (VCI=4)
• segment F5 flows (PTI=100)
• end-to-end F5 flows (PTI=101)
OAM F4 or F5 tests are used to check virtual path or virtual channel availbility
between two DSL devices. Segment flows are terminated at the connecting point
• Virtual Channel (VC) Logical connections between ATM devices
• Virtual Path (VP)
A bundle of virtual channels
• Virtual Circuits
A series of virtual paths between circuit end points
Virtual Path
Virtual Channel
Segment
ATM Switch
Virtual Circuit (End-to-End)
Summary of Contents for P-2812HNU-51c
Page 2: ......
Page 8: ...Safety Warnings P 2812HNU 51c User s Guide 8 ...
Page 10: ...Contents Overview P 2812HNU 51c User s Guide 10 ...
Page 19: ...19 PART I User s Guide ...
Page 20: ...20 ...
Page 73: ...73 PART II Technical Reference ...
Page 74: ...74 ...
Page 88: ...Chapter 4 Status Screens P 2812HNU 51c User s Guide 88 ...
Page 118: ...Chapter 5 WAN Setup P 2812HNU 51c User s Guide 118 ...
Page 204: ...Chapter 9 Voice P 2812HNU 51c User s Guide 204 ...
Page 210: ...Chapter 10 File Sharing P 2812HNU 51c User s Guide 210 ...
Page 216: ...Chapter 11 Firewall P 2812HNU 51c User s Guide 216 ...
Page 223: ...Chapter 12 Certificate P 2812HNU 51c User s Guide 223 Figure 99 Certificate Details ...
Page 232: ...Chapter 13 Static Route P 2812HNU 51c User s Guide 232 ...
Page 236: ...Chapter 14 Policy Forwarding P 2812HNU 51c User s Guide 236 ...
Page 252: ...Chapter 16 Quality of Service QoS P 2812HNU 51c User s Guide 252 ...
Page 274: ...Chapter 19 Universal Plug and Play UPnP P 2812HNU 51c User s Guide 274 ...
Page 284: ...Chapter 21 Interface Group P 2812HNU 51c User s Guide 284 ...
Page 288: ...Chapter 22 System Settings P 2812HNU 51c User s Guide 288 ...
Page 292: ...Chapter 23 Logs P 2812HNU 51c User s Guide 292 ...
Page 300: ...Chapter 24 Tools P 2812HNU 51c User s Guide 300 ...
Page 320: ...Chapter 27 Product Specifications P 2812HNU 51c User s Guide 320 ...
Page 336: ...Appendix A Network Troubleshooting P 2812HNU 51c User s Guide 336 ...
Page 376: ...Appendix C Pop up Windows JavaScripts and Java Permissions P 2812HNU 51c User s Guide 376 ...
Page 388: ...Appendix D IP Addresses and Subnetting P 2812HNU 51c User s Guide 388 ...