Telco-initiated tests, Telco-initiated line loopback, Telco-initiated payload loopback – Paradyne U8777 User Manual
Page 89

8. Testing
8700-A2-GB20-40
May 2002
8-11
Telco-Initiated Tests
Hotwire 8777 Termination Units support Telco-initiated tests, as shown in the
following table.
Telco-Initiated Line Loopback
Hotwire 8777 Termination Units support line loopback, as specified in AT&T
TR 54016, AT&T TR 62411, and ANSI T1.403. A Telco-Initiated Line Loopback
loops the received signal on the DSX-1 interface back to the DSX-1 interface
without modification. Framing, CRC, and FDL bits are returned unaltered, and no
BPVs or other line coding errors are removed. DSL time slots mapped to the
DSX-1 port are sent all ones.
Telco-Initiated Payload Loopback
Hotwire 8777 Termination Units support payload loopback, as specified in AT&T
TR 54016 and ANSI T1.403. A Telco-initiated line loopback loops the received
signal on the DSX-1 interface back to the DSX-1 interface. Framing, CRC, and
FDL bits are regenerated at the point of the loopback, and BPVs are removed.
DSL time slots mapped to the DSX-1 port are sent all ones.
Activation and
Deactivation
Line
Loopback
Payload
Loopback
Remote Line
Loopback
In-Band Signal
Supported
Not Applicable
Not Supported
Bit-Oriented
Supported
Supported
Supported
Message-Oriented
Not Applicable
Not Supported
Not Applicable
CAP
DSL
Port
DSX-1
Port
CAP
T1
LIU
Framer
Framer
Transceiver
99-16252
All Ones
Telco
CAP
DSL
Port
DSX-1
Port
CAP
T1
LIU
Framer
Framer
Transceiver
99-16253
All Ones
Telco