Juniper JUNOSE 10.0.X PHYSICAL LAYER, Configuration Manual

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2.
Specify PPP as the encapsulation method on the interface.
host1(config-if)# encapsulation ppp
Testing Interfaces
Testing interfaces allows you to troubleshoot problems and to check the quality of
links at various layers in the interface stack. The router supports the following test
options:
■
Transmission of BERT patterns to remote devices
■
Receipt of BERT patterns from remote devices
■
Local loopback — The ability to loop the data back toward the router; on supported
line modules, also sends an alarm indication signal (AIS) out toward the network
■
Network loopback—The ability to loop the data toward the network before the
data reaches the frame
■
Remote loopback, which provides:
■
The ability to request that remote devices enter into loopback
■
The ability to be placed in loopback by remote devices
■
Connectivity tests to remote devices
Sending BERT Patterns
The router can send BERT patterns from different layers in the interface stack. For
a list of the modules that support bit error rate tests (BERTs), see
ERX Module Guide,
Appendix A, Module Protocol Support .
To send BERT patterns:
1.
Select a controller.
2.
Configure a specific layer in the interface to generate BERT patterns.
For information about BERT patterns, see “References” on page 117.
path ds1|e1 bert
■
Use to enable bit error rate tests using the specified pattern at the T1/E1 over
SONET/SDH VT layer.
■
Unlike other configuration commands, “path ds1|e1 bert” on page 145 is not
stored in NVRAM.
■
Specify one of the following options:
■
2^11 —Pseudorandom test pattern, 2047 bits in length
■
2^15 —Pseudorandom test pattern, 32,767 bits in length
■
2^20-O153 —Pseudorandom test pattern, 1,048,575 bits in length
Testing Interfaces
■ 145
Chapter 4: Configuring Channelized OCx/STMx Interfaces