Juniper JUNOSE 10.0.X PHYSICAL LAYER, Configuration Manual

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2^15 —Pseudorandom test pattern, 32,767 bits in length
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2^20-O153 —Pseudorandom test pattern, 1,048,575 bits in length
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Specify the duration of the test in the range 1–1440 minutes.
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Optionally, specify the unframed keyword to overwrite the framing bits.
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Example
host1(config-controll)# path 12 ds3 2 t1 14 bert pattern 2^11 interval 10
unframed
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Use the no version to stop the test that is running.
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See path ds3 t1 bert.
Receiving BERT Patterns
The router can receive BERT patterns from a remote device at the T1/E1 over
SONET/SDH VT and T1/E1 over T3 layers. To receive BERT patterns, configure the
interface on the router for network payload loopback and the remote interface to
use the line clock. Inaccurate results might occur if you use other loopback modes
or clock sources.
When the router is synchronized with and receiving BERT patterns from a remote
device, the router records the number of bit errors and the number of bits received.
To view these statistics, issue the
show controllers sonet command.
Enabling Local or Network Loopback
You can enable loopback tests on the router at the following layers in the interface
stack:
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SONET/SDH section layer
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T1/E1 over SONET/SDH VT layer
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T3 layer
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T1/E1 over T3 layer
See “Interface Stack” on page 112 for a description of the layers.
To enable local or network loopback:
1.
Select a controller.
2.
Configure local or network loopback at the desired layers in the interface.
loopback
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Use to configure the type of loopback at the SONET/SDH section layer.
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Specify one of the following options:
Testing Interfaces
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Chapter 4: Configuring Channelized OCx/STMx Interfaces