Running A Ber Test - Cisco 10000 Series Configuration Manual

Chapter 15 8-Port Unchannelized E3/T3 Line Card Configuration
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You must be in configuration interface mode to modify an E3 or T3 configuration, for example:
Router# configure terminal
Router(config)# interface serial 1/0/0
Router(config-if)#

Running a BER Test

You can configure an interface to run a BER test (bit error-rate test). The BER test checks network cables
and isolates apparent signal problems in the field.
Before you begin a BER test, you need to set up a remote loopback from the far-end (remote) DSU/CSU.
See
the loopbacks.
The following loopback commands cause the remote CSU/DSU to perform a full-bandwidth loopback
through its CSU:
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To run a BER test pattern on an interface, use the following interface configuration command:
bert [errors number | pattern pattern] interval time
[no] bert
Where:
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OL-8834-04
Specifying DSU Mode, page 15-10
Specifying DSU Bandwidth, page 15-11
Encapsulation Command, page 15-11
Equipment Loopback Command, page 15-12
Fallback-Clocking Command, page 15-12
Setting the Framing Type, page 15-13
Specifying the Idle-Character, page 15-13
Performing Loopback Tests, page 15-14
Entering MDL Messages, page 15-14
Setting the National Bit, page 15-16
Enabling Scrambling, page 15-16
"Performing Loopback Tests" section on page 15-14
causes a loopback toward the network before going through the CSU/DSU
loopback network line
framer.
loopback network payload
CSU/DSU framer.
errors number is 1 to 255
pattern pattern is:
– 0s—repetitive test pattern of all zeros (00000... )
– 1s—repetitive test pattern of all ones (11111... )
– 2^15—pseudo-random O.151 test pattern (32,768 bits in length)
– 2^20-O153—pseudorandom O.153 test pattern (1,048,575 bits in length)
2^23—test pattern
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alt-0-1—alternating 0s and 1s test pattern
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for additional information about configuring
causes a loopback toward the network after going through the
Cisco 10000 Series Router Line Card Configuaration Guide
Interface Configuration Commands
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