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CHAPTER 11 Diagnostics
ATM Loopback
Figure 78: Ping Results
ATM LOOPBACK
In order to isolate the ATM interface problems, you can use ATM OAM loopback cells to verify connectivity between VP/VC endpoints, as well as segment endpoints within the VP/VC.
ATM uses F4 and F5 cell flows as follows:
◆F4: used in VPs
◆F5: used in VCs
An ATM connection consists of a group of points. This OAM implementation provides management for the following points:
◆Connection endpoint: the end of a VP/VC connection where the ATM cell are terminated
◆Segment endpoint: the end of a connection segment
Figure 79: ATM Loopback
The following items are displayed on this page:
◆Select PVC — Selects the dedicated service link between the ADSL Router and the service provider that you want to to a loopback test on. (Default: 5/35)
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