Juniper SRX Series Manual page 100

PRBS 2^20-1 (as specified in ITU-T 0.153)
PRBS 2^23-1 (as specified in ITU-T 0.151)
PRBS 2^9-1
PRBS 2^11-1
PRBS 2^29-1
PRBS 2^31-1
QRSS 2^20-1 (as specified in ITU-T 0.151)
BERT results must be in the following form:
Received bit count
Received error count
In conformance with ANSI T1.107-1995, the 1-Port Clear Channel DS3/E3 GPIM supports both generation
and detection of FEAC codes, as well as line-loopback activate and deactivate control codes.
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