Telco-Initiated Payload Loopback; Telco-Initiated Remote Line Loopback - Paradyne 7974 User Manual

Telco-Initiated Payload Loopback

Telco-Initiated Remote Line Loopback

T1
DSX-1
LIU
Port
AIS
Framer
7900-A2-GB21-00
The Hotwire 7974 Standalone Termination Unit supports payload loopback as
specified in AT&T TR 54016 and ANSI T1.403. A Telco-initiated payload 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.
CAP
DSL
All Ones
Port
Transceiver
If Remote Telco Loopback is enabled, a Telco-initiated line loopback loops
received data at the remote unit and passes it back to the Telco through the local
unit.
The following figure shows the data flow for a remote Telco-initiated line
loopback.
Remote
CAP CAP
Framer Transceiver
August 2000
CAP T1
LIU
Framer Framer
Local
CAP CAP
DSL
Transceiver Framer
Testing
DSX-1
Telco
Port
99-16253
T1
DSX-1
LIU
Telco
Port
Framer
98-16109
8-19