Cisco Systems 15454-FTF2 3.2 Bit Error Rate Testing

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Cisco ONS 15454 Reference Manual, R8.5.x
78-18106-01
Chapter 3 Electrical Cards
3.2 Bit Error Rate Testing
3.2 Bit Error Rate Testing
The bit error rate testing (BERT) feature can be used to test the connectivity, error rate, and error count
of the traffic running on an electrical input/output (I/O) ca rd port. The BERT feature is currently
supported for ONS 15454 DS1/E1-56 and DS3XM-12 electrical cards only.
BERT is broadly classified into two components—Test Pattern Generator (TPG) and Test Pattern
Monitor (TPM) and is called Test Pattern Generator and Monitor (TPGM) when referring to Test Pattern
Generator and Monitor.
TPG generates test patterns like PRBS15, PRBS20, PRBS23, QRSS and ATL1s0s (alternating ones and
zeroes). TPM monitors test patterns like PRBS15, PRBS20, PRBS23, QRSS and ALT1s0s. TPG and
TPM inject and monitor errors in the test pattern for both single bit and multirate (1.0E-3, 1.0E-4, 1.0E-5
and 1.0E-6) errors.
TPGM-L enables test pattern generation and monitoring on the line side. This option is not available for
the DS1 port in the DS3XM-12 card because you can configure DS1 port on the backplane side only.
TPGM-B enables test pattern generation and monitoring on the backplane side. You can enable TPGM-B
on a port only if the port has a bidirectional circuit.
Note The port must be in Out-of-Service and Maintenance (OOS-MT) state before enabling TPGM-L or
TPGM-B. OOS-MT state puts the circuit cross-connects to a service state. This service state does not
interrupt traffic flow and allows loopbacks to be performed on the circuit. OOS-MT however, suppresses
any alarms and conditions. Change the administrative state to IS, OOS, or IS-AINS when testing is
complete. For information on how to set the port to OOS-MT st ate, see the “DLP-A230 Change a Circuit
Service State” task in the Cisco ONS 15454 Procedure Guide, Release 8.5.
Note To enable TPGM-L or TPGM-B on a DS1 port, the line framing type must be D4, ESF, or unframed.
Note At any given time, you can enable BERT mode only on a single port of a card.
The following table summarizes if BERT can be enabled on the line side or backplane side for
DS1/E1-56 and DS3XM-12 electrical cards.
Note “Yes” indicates that BERT can be enabled on the line side (TPGM-L) or backplane side (TPGM-B).
For information on how to enable BERT on the DS1/E1-56 and DS3XM-12 cards, see the
Cisco ONS 15454 Procedure Guide, Release 8.5.
Table 3-3 Enabling BERT on Line Side and Backplane Side
DS1/E1-56 card TPGM-L TPGM-B
DS1 Port Yes Yes
DS3XM-12 card
DS1 Port No Yes
DS3 Port Yes No