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Configuring E1 BERT Properties


This topic discusses BERT properties for the E1 interface specifically. For general information about the Junos OS implementation of the BERT procedure, see Configuring Interface Diagnostics Tools to Test the Physical Layer Connections.

You can configure an E1 interface or a CE1 or E1 partition on a channelized PIC to execute a bit error rate test (BERT) when the interface receives a request to run this test. You specify the duration of the test and the error rate to include in the bit stream by including the bert-period and bert-error-rate statements at the [edit interfaces interface-name e1-options] hierarchy level:

By default, the BERT period is 10 seconds. You can configure the BERT period to last from 1 through 239 seconds on some PICs and from 1 through 240 seconds on other PICs. Standard CE1, standard E1, E1 IQ, and E1 IQE interfaces, and PICs partitioned to CE1 and E1 channels, support an extended BERT period range, up to 86,400 seconds (24 hours), and have a default BERT period value of 240 seconds.


When configuring E1 and CE1 interfaces on 10-port Channelized E1/T1 IQE PICs, you must include the bert-period statement at the [edit interfaces ce1-fpc/pic/port] hierarchy level.


When configuring CE1 interfaces on the 16-port Channelized E1/T1 Circuit Emulation MIC (MIC-3D-16CHE1-T1-CE), you must include BERT configuration options at the [edit interfaces ce1-fpc/pic/port] hierarchy level.

rate is the bit error rate. This can be an integer from 0 through 7, which corresponds to a bit error rate from 10–0 (0, which corresponds to no errors) to 10–7 (1 error per 10 million bits). The default is 0.


The bit-error-rate statement in BERT procedure is not supported on the 16-port Channelized E1/T1 Circuit Emulation MIC (MIC-3D-16CHE1-T1-CE).

Individual concatenated E1 interfaces do not support the bert-algorithm configuration statement. For individual concatenated E1 interfaces, the bert-algorithm statement at the [edit interfaces interface-name e1-options] hierarchy level is ignored. The algorithm for the E1 BERT procedure is pseudo-2e15-o151 (pattern is 215–1, as defined in the CCITT/ITU O.151 standard).

For channelized E1 intelligent queuing (IQ and IQE) interfaces, you can configure the BERT algorithm by including the bert-algorithm statement at the [edit interfaces ce1-fpc/pic/port e1-options] or [edit interfaces e1-fpc/pic/port e1-options] hierarchy level:

For a list of supported algorithms, enter a ? after the bert-algorithm statement; for example:

For specific hierarchy information, see individual interface types. For information about running the BERT procedure, see the CLI Explorer.