1. Choose Network > T1 Diagnostics.
  2. Choose the loopback test you want to run from the Loopback drop-down list and click Submit. Loopback tests are described in T1 Loopback Tests, Alarms, and Counters.

  3. Select the BERT test type from the BERT menu and click Submit.
    The BERT test sends a framed Quasi Random Bit Sequence (QRBS) on the T1 link and monitors the receive path for bit errors. A BERT test is usually run in conjunction with a network loopback at the remote end so that the test pattern sent by the EdgeMarc can be compared to the pattern received on the same interface. The EdgeMarc can send a QRBS 2^15-1 and a QRBS 2^20-1 pattern.

    The EdgeMarc also responds to network-generated, AT&T formatted loop up/down codes. Loopback codes sent from far-end equipment loop the T1 interfaces back toward the network. T1 diagnostic counters are described in T1 Loopback Tests, Alarms, and Counters.