5-19
PA-MC-T3-EC Port Adapter Installation and Configuration
OL-10589-02
Chapter 5 Configuring the Channelized Mode
Configuring a Channelized T3 Link
Configuring a BER Test on a T1 Line
Bit error rate test (BERT) circuitry is built into the PA-MC-T3-EC. With BER tests, you can test cables
and signal problems in the field. You can configure BER tests on each of the 28 T1 lines, but only one
BER test can be active at a time.
There are two categories of test patterns that can be generated by the onboard BER test circuitry:
pseudorandom and repetitive. The former test patterns are polynomial-based numbers and conform to
the CCITT/ITU O.151 and O.153 specifications; the latter test patterns are zeros or ones, or alternating
zeros and ones.
A list of the available test patterns follows:
•
Pseudorandom test patterns:
–
2^11 (per CCITT/ITU O.151)
–
2^15 (per CCITT/ITU O.151)
–
2^20 (per CCITT/ITU O.153)
–
2^20 QRSS (per CCITT/ITU O.151)
–
2^23 (per CCITT/ITU O.151)
•
Repetitive test patterns:
–
All zeros (0s)
–
All ones (1s)
–
Alternating zeros (0s) and ones (1s)
Both the total number of error bits received and the total number of bits received are available for
analysis. You can set the testing period from 1 minute to 14,400 minutes (240 hours), and you can also
retrieve the error statistics anytime during the BER test.
Note
BER testing for the T3 link is not supported in channelized T3 mode. It is only supported for
unchannelized T3 ports.
When running a BER test, your system expects to receive the same pattern that it is transmitting. To
accomplish this, two common options are available:
•
Use a loopback somewhere in the link or network.
•
Configure remote testing equipment to transmit the same BER test pattern at the same time.
Sending a BER Test Pattern on a T1 Line
You can send a BERT pattern on a T1 line with the
t1
t1-line-number
bert pattern
pattern
interval
time
[
unframed
]controller command. where:
•
t1-line-number
is 1 to 28.
•
time
is 1 to 14400 minutes.
•
pattern
is one of the following:
–
0s, repetitive test pattern of all zeros (as 00000...)
–
1s, repetitive test pattern of all ones (as 11111...)
–
2^11, pseudorandom test pattern (2,048 bits long)
