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ATM Physical Layer Statistics
9-11
Figure 9-5
Physical Layer Statistics
Current Sample
Specifies the number of seconds
elapsed within the current sampling period.
SONET/SDH counters are accumulated over a period
of 15 minutes (900 seconds). At the end of the 15
minute sampling period, the software stores the
results of the current sampling period, and resets the
values shown on the screen to zero.
The results of the previous 96 sampling periods can
be accessed through the SONET MIB using a MIB
Browser.
Physical Layer statistics are broken down into the
following layers:
■
Path
— The Path Layer deals with the mapping of
ATM cells to SONET or SDH frames. The ATM
Module supports 1 path.
■
Line
— The Line Layer provides synchronization
and multiplexing functions for the Path Layer
across the physical medium.
■
Section
— The Section Layer deals with framing,
scrambling, and section error monitoring.
Physical Layer errors are measured in units called
Seconds:
each
Second
is a second in time
.
In the following statistics a
second
is considered
errored if it contains a
Coding Violation
.
A
coding violation
occurs when the parity check in
the SONET or SDH frame indicates that the cell
payload has been corrupted.
A
second
is considered severely errored if it contains
16
coding violations
for a path or section, or 32
coding violations
for a line counter.
A
second
is unavailable if 10 continuous severely
errored
seconds
are seen at the ATM interface.
A
second
becomes available again, when 10
consecutive
seconds
are received that are not severely
errored.
Summary of Contents for OPTIONS ATM OC-3c
Page 1: ...8271 Nways Ethernet LAN Switch ATM OC 3c Module User s Guide...
Page 6: ......
Page 10: ...4 ABOUT THIS GUIDE...
Page 23: ...Asynchronous Transfer Mode ATM Layer 2 11 Figure 2 7 Switching Cells using VPI and VCI values...
Page 28: ...2 16 CHAPTER 2 NETWORK LAYER CONCEPTS...
Page 31: ...Extending VLANs into the ATM Network 3 3 Figure 3 3 Extending VLANs into the ATM Network...
Page 32: ...3 4 CHAPTER 3 VIRTUAL LAN CONCEPTS...
Page 39: ...Campus Configuration 5 3 Figure 5 2 Campus and Cost Sensitive Network...
Page 50: ...7 2 CHAPTER 7 ACCESSING MANAGEMENT FEATURES Figure 7 1 Screen Map...
Page 80: ...9 14 CHAPTER 9 MONITORING THE ATM MODULE...
Page 87: ...Safety Notices A 7 IEC 950 SELV SELV...
Page 88: ...A 8 APPENDIX A SAFETY INFORMATION...
Page 90: ...B 2 APPENDIX B SCREEN ACCESS RIGHTS...
Page 94: ...C 4 APPENDIX C ATM MODULE TECHNICAL SPECIFICATIONS...
Page 98: ...D 4 APPENDIX D TROUBLESHOOTING Figure D 1 Troubleshooting Flow Diagram...
Page 120: ...E 2 APPENDIX E TECHNICAL SUPPORT AND SERVICE...
Page 136: ...2 BIBLIOGRAPHY...
Page 140: ...4 INDEX...