257e1 bertSyntax e1 line-number bert pattern { 2^11 | 2^15 | 2^20 | 2^23 | qrss } time number[ unframed ]undo e1 line-number bertView CE3 interface viewParameter line-number: E1 channel number, in the range 1 to 28.pattern: Specifies BERT test mode, which can be 2^11, 2^15, 2^20, 2^23, andQRSS.2^11: Specifies the code stream transmitted is the 11th power of 2 bits in length.2^15: Specifies the code stream transmitted is the 15th power of 2 bits in length.2^20: Specifies the code stream transmitted is the 20th power of 2 bits in length.2^23: Specifies the code stream transmitted is the 23th power of 2 bits in length.qrss: Specifies the code stream transmitted is the 20th power of 2 bits in lengthand the number of successive 0s in the code stream is no more than 14.time number: Sets the duration (in minutes) of a BERT teat. The number argumentis in the range 1 to 1,440.unframed: Sets the overhead bits of the padding frames for BERT test.Description Use the e1 bert command to enable BERT test for an E1 channel created on aCE3 interface.Use the undo e1 bert command to disable BERT test.Multiple BERT test modes exist, as defined in ITU O.151, ITU O.153, and ANSIT1.403-1999. Currently, 2^11, 2^15, 2^20, 2^23, and QRSS are available on E1channels created on CE3 interfaces.To perform a BERT test, the local end transmits test data stream, which is returnedafter reaching specific nodes. The local end then checks for the bit error rate bycomparing the returned data stream with the original, through which the state ofthe link can be determined. BERT test requires that data stream can be loopedback on specific nodes. You can achieve this by enabling remote loop back on thepeer.You can use the bert command to set the test mode and the test duration. Duringthe process of a BERT test, you can check the state and the result of the test. Formore information, refer to “display controller e1” on page 205.Example # Perform BERT test in QRSS mode on E1 channel 1 created on CE3 2/0 interface,setting the duration to ten minutes.
